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355 Cards in this Set
- Front
- Back
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• Myocardial Ischemia is a reversible condition caused by
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a temporary deficiency in the supply of oxygen to the myocardium due to atherosclerotic narrowing of the vessel.
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• Myocardial Infarction is an irreversible condition leading to death of a portion of the myocardium caused by
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total occlusion of a coronary artery by a clot usually formed at the site of a severe coronary artery atherosclerotic narrowing.
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• Cardiomyopathy is a category of diseases associated with either
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abnormal enlargement of the myocardium (hypertrophic myopathy) or inability to contract effectively in spite of an adequate blood supply (dilated myopathy), resulting in thinning of the muscle and dilation of the chambers, which causes altered function.
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What is hypertrophic myopathy
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abnormal enlargement of the myocardium
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What is dilated myopathy
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inability to contract effectively in spite of an adequate blood supply, resulting in thinning of the muscle and dilation of the chambers, which causes altered function
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• Heart Failure is
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an end-stage condition defined by diminished heart function, usually due to a preexisting condition that results in impaired contractile performance.
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• Atherosclerosis progresses from small ____deposits in the wall of vessels in the puberty portion of the life cycle may be controlled by some degree by ____, ____, _____, ____
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lipid, diet, cholesterol, genetic heritage, life style
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• ________ are also called fatty streaks
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lipid deposits
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• A 50% narrowing of the vessel lumen may
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restrict blood flow, but cause no symptoms.
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• Radionuclide imaging studies for atherosclerosis are used to detect areas of the myocardium where ____ and ____is diminished
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blood flow, oxygen
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• Ischemia
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decreased tissue perfusion and decreased heart contraction in affected area.
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• Adult Heart-weighs about ____g (____lbs) and holds about ____ml (____ oz) of blood
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300, 0.66, 500, 16.6
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• What is the Pericardium
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clear, fibrous sac which covers the heart and contains small amount of lubricant between the myocardium (moving surface of heart muscle) and other chest structures.
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• What is the myocardium
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moving surface of heart muscle
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• Right Side of Heart consists of ____ and ____ and accepts blood from the body and pumps blood to ____ for ____
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upper atrium, lower ventricle, lungs, oxygenation
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• Left Side of Heart consists of the ____ and ____and accepts blood returning from the ____ and pumps it to the _____________
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upper atrium, lower ventricle, lungs, body regions
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• The atrium is a thin-walled chamber that serves as
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temporary reservoirs for blood returning to the heart
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• The atria are separated by
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interatrial septum, a thin muscular wall
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• What is the interatrial septum
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a thin muscular wall that separates the atria
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• Ventricle is a muscular chamber that
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pumps blood away from heart
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• Ventricles are separated by
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the thick, muscular interventricular septum.
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• Valves separate (2)
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atria from ventricles, ventricles from the arteries
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• Valves prevent (2)
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the backflow of blood from ventricles to atria during ventricular contraction or from the arteries to the ventricles during ventricular relaxation.
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HEART ANATOMY – What is made up of three leaflets or cusps and where is it located
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tricuspid valve between right atrium and ventricle
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HEART ANATOMY – What part of the heart is pyramid shaped with the tricuspid at the roof
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right ventricle
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HEART ANATOMY - where nutrients/oxygen are exchanged for waste products and CO2
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capillaries
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HEART ANATOMY – Left main coronary artery divides into 2 main branches
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Left anterior descending artery (LAD) and Left circumflex artery
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HEART ANATOMY – artery which supplies oxygen/nutrition to interventricular septum and anterior wall of left ventricle
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LAD (left anterior descending artery)
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HEART ANATOMY – Which artery supplies left atrium and posterior/lateral walls of left ventricle
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Left circumflex
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HEART ANATOMY – Which artery supplies the inferior wall of left ventricle, free wall of right ventricle, and right atrium
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Right coronary artery
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Systole
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period of ventricular contraction.
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• Diastole
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period of ventricular relaxation.
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• End-diastolic volume
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quantity of blood in ventricle at end of diastole
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• Average EDV
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about 150ml. in average adult.
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• Interval of isovolumetric contraction
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no change in blood volume: interval after mitral valve closure but before generation of sufficient pressure to open aortic valve
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• Cardiac output
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quantity of blood ejected from left ventricle over 1 minute interval, expressed in liters/minute
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• What is normal cardiac output
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70kg.
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• Adult’s cardiac output is approx. _____________at rest
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5-6 L/min
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• Stroke Volume
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quantity of blood ejected in single beat, expressed in ml
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• Normal stroke volume
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80-100ml.
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• Sinoatrial (SA) Node
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fastest pacemaker for heart, small mass cells embedded in right atrium wall, serves as impulse generator for remainder of heart.
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• Conducting System
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series of specialized muscle fibers that carries electrical messages from atrioventricular node to far reaches of ventricular myocardium.
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• Bundle of His
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specialized conducting system which signals ventricular systole.
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• P wave is electrical signal for
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atria to contract.
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• QRS complex serves to signal
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ventricles to contract.
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• T wave identifies
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an electrical reset of ventricles for next cardiac cycle.
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• The heart is electrically silent during much of ____
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diastole.
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• Normal ECG pattern is repeated ____-____times/minute
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60-100
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• Normal cardiac rhythm is regular and the P-wave, PR interval, and QRS complex occur at _____________
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constant intervals.
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• It is the ____-segment that a lack of blood flow may be demonstrated by a depression of this line below the baseline
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ST
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• When the ST segments demonstrates a depression below the baseline what does it signal
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lack of blood flow
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• During a stress study, the patient’s ECG may exhibit ____-____depression, indicative that the demand or supply of blood to the myocardium has ____
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S-T, changed
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• Premature systoles may originate in _____________ or _____________or coupled together. If they occur every other beat, the rhythm is called ____.
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atria (PACs), ventricles (PVCs) , bigeminy
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• Premature systoles of the atria are known as
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Premature Atrial Contraction (PACs)
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• Premature systoles of the ventricles are known as
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Premature Ventricular Contraction (PVCs)
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• Ventricular tachycardia
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rapid rate that is life threatening: if left untreated may develop into ventricular fibrillation or death.
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• Atrial fibrillation
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disorganized electrical firing at multiple sites in atria, causing rapid, irregular ventricular rate.
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• Left bundle branch block
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abnormal conduction pattern associated with slower depolarization of conducting pathway through the left ventricle than right.
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• Right bundle branch block
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slower depolarization through the right ventricle than the left.
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• All electrical abnormalities of the heart may have substantial effects on nuclear imaging studies of _____________
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ventricular function.
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• Agents for Myocardial Perfusion
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Thallium-201, Tc99m-labeled perfusion agents such as Sestamibi, Myoview,etc.
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• Agents to label blood to measure ventricular function
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Tc99m RBCs or Tc99m albumin.
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• Agents to detect acute myocardial necrosis
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Tc99m pyrophosphate (PYP)
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Best to use _____________when there are poor count rates/short data collection time
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Planar Imaging Techniques
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• Best to use ____ imaging when there are high count rates, such as when using Tc99m
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SPECT
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• Digital images that are recorded with single/multi detectors with extrinsic resolution better than _____________
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5mm FWHM
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• 2mm (FWHM) is ____than 5mm (FWHM)
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better
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• The ____the FWHM the ____the resolution
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narrower, better
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• What is FWHM
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It is a measurement of curve peak characteristics by comparing the curve width at half the peak height with the value at which the peak occurs, and used to express spatial resolution of an imaging device.
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• For FWHM, if we measure a _____________and plot the _____________ across its center, a ____-shaped curve results
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single point source, intensity profile, bell
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• The FWHM of a bell shaped curve can be used to measure
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spatial resolution quantitatively.
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• The more ____ the bell curve, the ____ the spatial resolution
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narrow, better
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• The better the spatial resolution
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the better the ability of the camera to detect small abnormalities manifested as different radionuclide concentrations in clinical images.
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• With FWHM the spread of the point or line is indicative of
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the degree of blurring or loss of resolution of the camera.
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• Why should the heart be imaged from many perspectives
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Because heart disease if focal
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• Heart disease is Focal means that
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heart disease may start (originate) at any point on the heart muscle.
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• SPECT stands for
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(Single Photon Emission Computed Tomography)
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• SPECT is best for imaging the
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heart muscle
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• planar imaging can sample the _____________the best
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left ventricle surfaces
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• SPECT Imaging Requires a minimum of _____________ sampling
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180 degree
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• SPECT images go from the ____ position to ____
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RAO, LPO
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• SPECT slices are reconstructed as ____, ____,____ and ____ slices through heart
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transverse, sagittal, coronal, oblique
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• SPECT uses ____, ____, or ____ cameras
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single, dual, multi-head
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• 2 detector system images in _____________ of a single head when ____ degree images occur
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half the time, 180
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• 3 detector system images in _____________ if ____ degrees preferred.
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1/3 the time, 360
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• Detectors should be as close to patient as possible to provide
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maximal spatial resolution.
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• Use step and shoot method of acquiring data so that there is greater ____, that is, there is no _____________ blurring of the heart muscle
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resolution, detector motion
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• Star Artifact
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resembles the spokes of a wheel when inadequate sampling of the organ occurs with SPECT, Gaps between the steps are too great, greater than 6 degrees.
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• Circular orbit
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maximizes distance between collimator and body surface.
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• Ellipse orbit
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keeps detectors close to heart providing better resolution., but it is more complex to set up than other orbits
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• Single detector ____ degree acquisition
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180
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• Dual detector ____ degree acquisition
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90
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• Why is dual detector only 90 degrees of acquisition
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Because collimator resolution is maximized, and attenuated photons from the patient’s posterior side are not included in the reconstruction of images due to the closeness of the heart to the detector.
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• 180 degree studies (single head) have higher ____ than 360 degree acquisitions (triple head)
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contrast
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• dual detectors (90 degree) has ____ the sensitivity of the single head
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double
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• duel head detectors which can ____imaging time, ____ quality of study because of ____ count density, slightly shorten time to accomplish both of the above
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decrease, increase, doubling
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• Advantage of using 360-degree imaging instead of 18
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elimination of some artifacts.
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• To maximize resolution
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use a high or ultra-high resolution collimator.
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• Gated Perfusion Studies are helpful in
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differentiating attenuation(any condition that results in a decrease of radiation intensity) artifacts from perfusion abnormalities, to assess ventricular volumes and regional wall motion.
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• Attenuation is
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any condition that results in a decrease of radiation intensity
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• Other things to consider for SPECT reconstruction-adequate filters to see _____________ clearly, slices should occur _____________ thick to avoid ____, use cine display before reconstruction to see patient ____ and repeat acquisition if there are multiple areas of motion with movement greater than _____________ because can cause ____ and cause _____________ interpretation
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heart borders, 1-2 pixels, gaps, motion, 2 pixels, artifacts, false positive or negative
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• Stress Studies are used to detect
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myocardial ischemia and the location and extent, and detect a relative decrease in blood flow to the myocardium.
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• During stress exercise, radiopharmaceuticals are injected during ____ exercise and the patient is encouraged to exercise for about _____________ so that the tracers are deposited in the tissues
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peak, 1-2 more minutes
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• When doing walking exercise studies, the heart rate should be between ____-____% of maximum, depending on patient’s age, or ____-age of patient = _____________ to be achieved
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85-100, 220, max heart rate
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• Exercise Protocols-The purpose of the treadmill exercise test is to evaluate
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the potential CAD patient in a controlled setting by recreating symptoms the patient experiences on exertion.
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• There are 2 main exercise protocols
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Bruce Protocol and modified Bruce Protocol
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• The Bruce Protocol is
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most common, speed and elevation of treadmill increases every 3 minutes (stages)so that patient’s workload/heart rate increase.
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• The modified Bruce Protocol is
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enables slight elevation every 3 minutes but speed remains at slow pace, generally, reserved for patients with limited exercise capacity.
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• Indications to Prompt Myocardial Perfusion Studies
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1. Detection/Evaluation of Coronary Artery Disease 2. Evaluation of Possible Candidates for CABG or Angioplasty 3. Evaluation of Physical Indicators: myocardial infarction,chest pain, shortness of breath, hx or family hx of heart disease 4. Evaluate lab values:elevated levels of troponin and myoglobin(specific indicators of heart damage)
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• Contraindications for not doing Stress Test (5)
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1. Patient is experiencing chest pain. 2. Patient should discontinue chemical stressors, such as caffeine, or broncho dilators (theophylline, Theo-Dur) or Persantine (dipyridimole), which is a coronary vasodilator. 3. Patient has extremely high BP. 4. Patient is medically unstable. 5. Patient has lung conditions may get asthmatic reaction if using Adenosine or Persantine during stress. Use Dobutamine instead.
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• Examples of broncho dialators are
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theophylline and theo-dur
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• What is persantine and what is another name for it
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coronary vasodilator, dipyridimole
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• If a patient has lung conditions ____ and ____ may cause asthmatic reactions during stress so use ____ instead
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adenosine, persantine, dobutamine
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• How is thallium-201 produced
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by a cyclotron
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• What is the half life of thallium-201
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73.06 hours
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• What energy is thallium-201 (2)
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produces about 80 keV of Hg-201 x-rays and 135-167 keVof gamma photons
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• Thallium-201 is excreted through
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the bowel/kidneys
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• What dose of thallium-201 is used and why
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may only use about 3-4 mCi because of long effective half-life
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• Thallium-201 gives patient’s kidneys what dose
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producing 1.2rads/mCi to the patient’s kidneys.
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• Thallous Chloride is similar to ____ and distributes with ____ and ____ and seeps out to ____ and redistributes so that all viable ____ is seen
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potassium, Na, K, myocardium, myocardium
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• Downfalls of Thallium-201 use are
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long effective half-life and low energy, which makes attenuation artifacts more prominent.
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• Tl-201 is quite useful when looking for
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redistribution
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• In the ischemic myocardium, the relative amount of thallium in the zone of diminished perfusion is ____ than that of the normally perfused zone
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lower
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• Loss of Tl-201 from the normally perfused zone is ____ than that of the ischemic zone if imaging continues for several hours (ex:do stress, then image, then have patient return in 4 hours for rest images). If using this protocol, patient should not eat since ____ ingestion makes thallium quickly clear from both ____ and ____ myocardium
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greater, glucose, normal, ischemic
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• The short, effective half-life of Tc99m enables injections of up to ____
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30mCi.
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• Tc99m perfusion tracers do not redistribute the same as Tl-201, but instead
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they concentrate in the liver and then go to the bowel.
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• With Tc99m perfusion tracers there is little myocardial ____ and that is why ____ injections are required for rest/stress images
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redistribution, separate
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• Patient protocols for Tc99m cardiac imaging (3)
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rest/stress on different days (each with doses of 20-30mCi), rest/stress same day (first with 10mCI, second with 20-30mCi 4-6 hr later to allow physical decay/biologic loss of radiopharmaceutical from myocardium), or utilizing both Tl-201 for rest and Tc99m for stress.
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• Advantages of using Tc99m/Thallium-201 protocol are that
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delayed images may be recorded with Tl-201 to detect viable myocardium and stress can be performed at the conclusion of rest imaging.
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• For ischemia detection, both ____ and ____ agents perform well, but when there is concern about _____________ or _____________, ____ is best
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Tl-201, Tc99m, severe ischemia, myocardial viability, Tl-201
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• Use ____ with Tc99m/Thallium-201 agents to see myocardial function and perfusion at the same time
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SPECT
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• Planar Images of the Heart are helpful to identify
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attenuation artifacts and detect rapidly changing conditions, such as lung uptake or left ventricular dilation, which may normalize 10-15 min after injection, so it stands to reason that imaging should begin within 10 minutes of injection to avoid redistribution of Tl-201.
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• 3 Standard Planar Images are
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anterior, 45 degree LAO, 70 degree LAO.
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• If the patient is obese, the diaphragm may obscure the ____ or ____wall of the ____, and the 70 degree LAO may have to occur with the patient on ____
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inferior, posterolateral, myocardium, right side
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• A Rule to Remember About Planar Imaging, If a physician wants you to image the patient with the best “_____________,” since all of us as people are different anatomically, use the detector head, find the best septal separation and subtract _____________ for the anterior angle and add _____________ for the steep LAO angle. For example, if the best angle is actually 35 degrees LAO, then the best anterior view would be _____________ RAO and the best steep LAO would be _____________ LAO instead of _____________
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septal resolution LAO angle, 45 degrees, 25 degrees, 10 degrees, 60 degrees, 70 degrees
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• SPECT offers improved image contrast compared to planar imaging, but ____ are a greater problem when it comes to patient ____ and ____
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artifacts, motion, attenuation
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• When using thallium, it is better to start imaging within ____ minutes of the exercise to avoid _____________
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10, myocardial creep or upward creep
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• What is myocardial creep or upward creep
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a phenomenon of myocardial motion due to a change in the degree of diaphragm movement as the patient begins to breath normally after higher levels of exercise.
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• Myocardial creep results in an artifactual lesion in the ____ or ____ regions of the left ventricle
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inferior, inferoseptal
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• After SPECT imaging occurs, then reconstruction occurs, as we have already talked about. On top of being able to reorient the images, most computer software allows for the tomographic images to be analyzed using the ____ type of display, where short axis SPECT images are arranged concentrically from the ____ of the ventricle (center) to the ____ (periphery). and the 3 dimensional myocardium is flattened into a single-plane map of the _____________
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Bull’s-eye, apex, base, left ventricle
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• Drugs That Can Affect Exercise Response include (9)
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Nitroglycerin, Long-acting Nitrates, Tranquilizers, Sedatives, Antiarrhythmic Agents, Beta Blockers, Diuretics, Antihypertensives, Digitalis
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When to discontinue Nitroglycerin
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disc. 1 hr. prior to test
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When to discontinue Long-acting Nitrates (nitropatch)
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1 day
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When to discontinue Tranquilizers/Sedatives
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1 day
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When to discontinue Antiarrhythmic Agents
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2 days
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When to discontinue Beta Blockers
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2 days
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When to discontinue Diuretics
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4 days
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When to discontinue Antihypertensives
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4-7 days
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When to discontinue Digitalis
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1-2 weeks
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• When would you use pharmacologic Stress Agents
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when patient has poor motivation or medications that hinder adequate myocardial demand,or when there are physical limitations.
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• Dipyridamole is also known as
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(Intravenous Persantine)
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• Dipyridamole causes
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vasodilation of the coronary bed, which creates a “myocardial steal” phenomenon that diverts blood away from the myocardium that is served by coronary arteries that may have significant stenosis.
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• How does dipyridamole work
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by increasing the local tissue level of adenosine, since it decreases the adenosine receptor metabolism in the body.
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• When dipyridamole is infused what happens
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coronary arteries free of atherosclerosis increase blood flow uniformly to all areas of myocardium, and when the tracer is given at the time of maximal effect, a normal scan is seen.
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• With dipyridamole If a vessel is narrowed
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flow distal to the narrowing does not increase to the same degree as that of normal arteries. This does not cause ischemia, as in exercise tests, but the basis is the same, and that is detection of CAD.
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• Patient Preparation for Persantine
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must be NPO at least 4-6 hours prior since stomach contents may cause nausea with drug or availability of blood to myocardium is changed: must be off of aminophylline or theophylline drugs because interferes with mechanism of drug:confirm patient’s drug sensitivities before administration:confirm if patient is asthmatic. Must be off of caffeine for 24 hours and xanthine-containing drugs at least 36 hours since they reduce effectiveness of vasodilation and may produce false negatives on patients with CAD.
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• Patients with drug sensitivities to persantine or aminophylline or patients with asthma or bronchospasms
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should not have study with dipyridamole because the condition may worsen.
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• for patients with lung disease dipyridamole studies should be
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postponed for 48 hours if they are on derivatives of the above medications.
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• Administration of Persantine
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Patient dose calculated by pharmacist at 0.56mg/kg of body weight. Max=60mg. Diluted to 50cc and delivered to patient 12.5cc/min or 0.14 mg/kg/min. Administer dose in four minutes, wait 2 minutes before injecting radiotracer, since peak action occurs at 2 minutes. Patient should be lying down for study since drug is vasodilator, which results in low blood pressure,usually a drop of about 10-15mmHg.
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• Common Side Effects of Persantine
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chest pain or tightness, pounding headache, dyspnea, or sometimes n/v. Persisting effects may be alleviated with aminophylline. Keep in mind, too, that if the patient’s blood pressure drop is profound, it can lead to death if not treated. Serious side effects include arrhythmias, severe hypotension, cerebral ischemia, stroke, or death, which are actually those seen with stress exercising.
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• How Adenosine works
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has same working mechanism as persantine but activates the A2 receptors on the cell membrane of smooth muscles instead of decreasing metabolism of adenosine produced endogenously, creating vasodilation
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• What is the ½ life of adenosine
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less than 10 secs
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• What is the ½ life of persantine
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20-30min
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• Adenosine’s short plasma half-life means that
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its side effects may be more transient (lasting only a short amount of time), and more severe.
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• Patient Preparation for Adenosine
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same as persantine, but dosage prepared differently by pharmacist, 240ug/kg of weight:infused at rate of 40ug/kg/min over six minutes:inject 1/2 way.
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• Which stress agent is the only one that actually increases heart rate making the heart pump harder and faster
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dobutamine
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• What reverses the effects of dobutamine
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beta blockers
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• Both adenosine /persantine act by
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increasing the flow of blood to the myocardium by vasodilation
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• dobutamine works by
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increasing the demand for blood by the myocardium
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• dobutamine is a
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positive inotropic agent that stimulates the beta-1 receptors, causing an increase in the force and frequency of the contraction. Essentially, this drug mimics exercise.effects.
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• What does a positive inotropic agent do
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increases myocardial contractibility
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• Patient Preparation for dobutamine
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patient should refrain from the use of beta blockers for at least 24 hours because they bind to the beta sites of the myocardium and inhibit effect of drug.
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• Administration of Dobutamine
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broken down into stages mimicing treadmillprotocol:IV infusion begins at rate of 5-10ug/kg/min and increasing every 3 minutes and may increase to 20,30, at physicians order. Atropine is given up to a total of 1 mg if 85% of maximal heart rate is not achieved.Tracer given when HR achieved.
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• Side Effects of dobutamine
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chest pain, dyspnea, ECG changes, nausea. Propranolol should be used to reverse side effects.
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• Remember, real stress test offers more info than ____ stress study, which cause increased blood flow to ____, making it difficult to see _____________
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pharmacologic, liver, lesions of inferior wall
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• Denial of blood to the myocardium by a _____________ or _____________ starts the process of myocardial infarction
|
blocked coronary artery, blunt chest trauma
|
|
|
• With a Myocardial cells begin to die and necrosis begins, which is essentially the ____________. Damaged myocyte becomes vulnerable to ____, the cells intracellular contents spill out into the ____ fluid in the form of proteins or serum enzymes such as ____, ____, ____, and ____ produces inflammation because of cellular change, then ____ ingest debris, and ____ cause scar at damaged area
|
loss of cellular integrity, macromolecules, extracellular, CPK, LDH, troponin, myoglobin, WBCs, fibroblasts
|
|
|
• With myocardio infarct the now permeable cell allows transfer of substances to and from the injured cell, and the cell actually loses its ability to _____________
|
regulate calcium.
|
|
|
• This cell process (similar to that of bone formation) enables us to use _____________, since this bone imaging agent will accumulate in the area of myocardial injury and it has a high binding affinity of ____ to proteins produced after injury
|
Tc99m labeled pyrophosphate (PYP), PYP
|
|
|
• It is important to know that acute infarct imaging needs to occur ____-____ hrs after injury and within ____ days of the injury since localization of PYP in the injured site diminishes. False negative results may occur, otherwise. _____________ may obscure seeing the myocardium, and increases with waiting time
|
24-72, 10, Fractured ribs
|
|
|
• Using PYP, bony structures in the chest are normally seen, since
|
PYP is bone imaging agent, but no soft tissue activity should be seen in heart area
|
|
|
• Increased PYP tracer in myocardium region is
|
abnormal, in other words, you should not be able to see the heart muscle on study.
|
|
|
• With PYP the physician usually compares
|
activity areas in bones to cardiac to grade severity of infarct
|
|
|
• PYP # 0
|
(no increase)
|
|
|
• PYP # 1+
|
(faint,diffuse increase but < rib cage levels)
|
|
|
• PYP # 2+ definition PLUS _____________
|
(definite activity increase equal to rib levels but < sternum. the patient has a subendocardial infarction with/without unstable angina and focal areas of necrosis
|
|
|
• PYP # 3+
|
(activity level equal to sternum levels
|
|
|
• PYP #,4+
|
activity level>than that of sternum levels).
|
|
|
• Positive PYP studies return to normal within a _____________
|
week to a month.
|
|
|
• PYP scan may be repeated in ____-____ days
|
7-10
|
|
|
• persistent abnormal PYP uptakes indicate
|
poor prognosis.
|
|
|
• A PYP reading of 3+ or 4+ indicates
|
acute transmural myocardial damage (the tissue in the entire wall thickness of the heart is involved).
|
|
|
• Cold PYP is used for
|
invivo MUGA scan and is injected before the Tc99m injection
|
|
|
• Performing the PYP Study, Collect medical history including
|
injuries or surgeries of chest, location, duration, frequency of pain, and lab values
|
|
|
• Administer ____-____ mCi Tc99m PYP IV
|
15-25mci
|
|
|
• With Tc99m PYP, Encourage patient to
|
drink fluids/void as with any bone imaging agent
|
|
|
• Begin PYP images ____-____ hrs after injection to make sure there is no residual tracer in the _____________
|
2-4, blood pool
|
|
|
• With PYP take planar images ____, ____, ____, ____
|
anterior,30 degree RAO, 45 degree LAO,left lateral
|
|
|
• PYP SPECT images are obtained using which collimators (2)
|
low energy, all purpose, or low energy, high resolution collimator
|
|
|
• With PYP Collect ____-____ counts per planar view, and SPECT imaging should incorporate ____ degree imaging and is helpful in seeing _____________
|
500,000-1,000,000, 360, small focal areas
|
|
|
• With PYP check for artifacts, such as _____________ (necklaces, items in shirt pockets)
|
attenuating objects
|
|
|
• With PYP unexpected _____________ may obscure the heart, or background from inadequate ____ may hinder imaging
|
bone mets, hydration
|
|
|
• In-111-protocol utilizes a key protein that is involved in the heart’s ____ apparatus, called ____, and an _____________
|
contractile, myosin, antimyosin antibody
|
|
|
• With In-111 if the cell membrane is intact the antibody cannot come in contact with the cell antigen so there will be no tracer uptake unless
|
there has been loss of cell membrane integrity.
|
|
|
• In the case of cell membrane damage, the ____ will enter the damaged cell and combine with the ____ so that In-111 tracer localization occurs
|
antimyosin, antigen,
|
|
|
• The ____ is labeled with In-111 using a ____ (____). This detection method is rare because of ____
|
antibody, binding agent, chelate, expense
|
|
|
• Planar images for an In-111Antimyosin Study include ____, ____, ____, and ____
|
45 LAO, left lateral, anterior, and SPECT.
|
|
|
• Inject ____ of In-111 and take images at ____ to ____ hrs, using ____-energy collimator
|
1.8mCi, 24, 72, medium
|
|
|
• The best In-111 results are obtained ____-____days after acute ____
|
2-4 , MI.
|
|
|
• In an In-111 study the focal area of increased activity signifies a _____________ whereas Diffuse uptake of lower intensity signifies _____________
|
transmural MI, subendocardial necrosis
|
|
|
• Difference in PYP vs. In-111 Antimyosin-PYP ____ size of infarct by ____ factor: both have reputation of ____% accuracy ____ detection
|
overestimates, 1.7, 90%, MI
|
|
|
• In-111 Antimyosin helpful with assessing _____________, but definitive diagnosis must come from ____, but the drawback of a ____ is that the procedure is invasive
|
myocardial necrosis, biopsy, biopsy
|
|
|
• Why is a biopsy to determine myocardial necrosis considered invasive
|
the physician has to enter the patient’s body to get the sample, and the sample is usually too small to evaluate the heart muscle as a whole.
|
|
|
• Heart transplant rejection imaging should be performed using same protocol as _____________ imaging
|
myocardial necrosis
|
|
|
• It is important to know that all patients have ____ at time of transplant and grafts have minimal ongoing ____ even when not being ____
|
necrosis, necrosis, rejected
|
|
|
• Within 1st year after a heart transplant the heart/lung ratio should be ____ and ____ have ongoing rejection so change in antirejection therapy should occur
|
< 1.5, >1.5
|
|
|
• What are the two techniques are used to assess cardiac function
|
the gated equilibrium (MUGA) method or the first-pass method.
|
|
|
• By doing function technique studies, we can assess the heart’s ability to
|
function as a pump when using tracers that remain in the blood pool.
|
|
|
• The information that we gain from function technique studies includes
|
size and shape of chambers, the motion of the walls during each beat, and the ejection fraction.
|
|
|
• Functional assessment of the heart describes the _____________ and _____________ of both ventricles, as well as ____ size and ____patterns. ____ is most common measurement
|
ejection fraction, regional motion, atrial, contraction, LVEF
|
|
|
• For first pass studies, always inject
|
in the antecubital space
|
|
|
• For first pass studies the patient must have a normal ____ and first pass studies are always ____
|
EKG, gated
|
|
|
• When doing the first-pass study, the tracer only stays in the blood stream for
|
a minute or less as it passes to the heart chambers
|
|
|
• The upside to the tracer quickly leaving the blood stream in a first pass study is that
|
if the study has to be repeated, you can do this since the radiotracer clears.
|
|
|
• The equilibrium study (MUGA) requires tracer to remain in blood pool for
|
30 minutes.
|
|
|
• First Pass Study isfor (4)
|
evaluation of patients with left ventricular dysfunction, interventricular shunts, myocardial infarction, ischemia.
|
|
|
• The first pass technique is used to record
|
the initial passage of the tracer through cardiac chambers.
|
|
|
• Advantage to first-pass analysis is that (2)
|
tracer activity is limited to one chamber at a time, so it is easier to define ROIs: also, background interference is minimized because one structure is visualized at one time.
|
|
|
• First-pass technique is sometimes the ____ to the MUGA study
|
precursor
|
|
|
• A pretest EKG is necessary before doing a _____________
|
first-pass study.
|
|
|
• For a first pass study a good heart beat without ____ is necessary because your study is going to be represented by _____________. For example, if the ____ caused the tracer to enter the _____________ that is out of acquisition sequence setup, then the study may be worthless
|
PVCs, 2-3 heart cycles, PVC, right ventricle
|
|
|
• Patients with frequent PVCs should have an
|
equilibrium gated study with capabilities of bad beat rejection equipment.
|
|
|
• Read* Radiotracers used for First-Pass Studies-If no other studies are planned after, then Tc99m DTPA can be used for multiple injections since it has rapid clearance through the kidneys, or Tc99m-pertechnatate, which cannot be used for multiple injections because it concentrates in the gastric mucosa making it difficult to see the inferior surface of the heart, and the same limitations apply to Tc99m-sulfur colloid use.If an equilibrium study is to follow the 1st pass study, then the patient’s blood should be pre-tinned with stannous pyrophosphate, then Tc99m-pertechnetate will be injected. Tc99m sestamibi, myoview, cardiolite may be used for 1st pass angiography if myocardial perfusion study is planned later
|
???
|
|
|
• Tracer volume for a first pass study should be limited to _____________ and injected through butterfly that is placed in the _____________ vein of the forearm
|
1 ml or less, basilic (medial)
|
|
|
• Using a small volume of tracer for a first pass study enables the injected bolus to
|
remain intact as long as possible as it travels up the arm to the subclavian and eventually to the heart.
|
|
|
• Which technique should be used to inject a first pass study
|
Oldendorf injection technique should be used to deliver the radiotracer accurately.
|
|
|
• Some facilities may inject the tracer for a first pass study through
|
a line started in the external jugular vein so that there is a shorter pathway.
|
|
|
• Oldendorf Technique steps (10)
|
1. Before injecting, a BP cuff is placed proximal to the catheter. 2. Palpate the radial pulse and inflate cuff until pulse cannot be felt. 3. Reduce cuff pressure by 10mm Hg. 4. Keep cuff inflated for one minute. 5. Increase above systolic pressure. 6. Inject tracer over 1-3 seconds. 7. Start computer. 8. Remove cuff quickly. 9. Flush. 10. Have patient breathe normally during study.
|
|
|
• Collimator used for 1st pass study
|
LEAP or LE high resolution.
|
|
|
• Patient position for first pass study
|
supine: use source to locate sternal notch and xiphoid and make sure that your arm with IV is in camera view (you want to watch the tracer move through the system).
|
|
|
• 1st pass camera position to look for overall cardiac assessment
|
position anterior
|
|
|
• 1st pass camera position to look for optimal separation of right/left ventricles
|
45 degree LAO
|
|
|
• 1st pass camera position to facilitate calculation of LVEF/RVEF on 1st pass
|
10 degree RAO
|
|
|
• Acquiring the Data for 1st pass study
|
60 seconds of data should be obtained to accurately record the transit time of the tracer (normal is 15 secs but patients with heart disease may take 45 secs).
|
|
|
• Departmental first pass acquisitions are set-up to
|
acquire study so that the patient’s heart rate in bpm incorporates the frames/heart cycle, frames/sec and total number of frames acquired.
|
|
|
• Data Analysis of 1st pass study uses time-activity curves that are generated from ____ of like frames that have been added together, such as those for the _____________, _____________ and ____
|
ROIs, superior vena cava, rt/lt ventricles, lungs
|
|
|
• It is important that 1st pass study frames are set up so that
|
when ROIs are drawn the activity has cleared the right ventricle when looking at the left because this can cause an erroneous LVEF.
|
|
|
• Calculating Ejection Fraction-
|
EF = (End-diastolic counts - End-systolic counts) End-diastolic counts
|
|
|
• Normal Results for a 1st pass study
|
LVEF is 50-80%:RVEF is 40-60%: bolus travels through right atrium and ventricle to lungs and back through left atrium and ventricle with no obvious obstruction or path alteration.
|
|
|
• Abnormal Results for a 1st pass study (4)
|
akinesis (no movement), hypokinesis (decreased wall motion), dyskinesis (abnormal wall movement such as that of a left ventricular aneurysm), LVEF 35-45% or less
|
|
|
• 30% LVEF is significant of
|
severe impairment.
|
|
|
• What is akinesis
|
no movement
|
|
|
• What is hypokinesis
|
decreased wall motion
|
|
|
• What is dykinesis
|
abnormal wall movement such as that of a left ventricular aneurysm
|
|
|
• MUGA Study aka
|
Radionuclide Ventriculogram
|
|
|
• MUGA measures
|
the parameter of cardiac function (ejection fraction)
|
|
|
• MUGA can be repeated often to measure
|
patient progress during cardiac drug therapy or effects of chemotherapy on CA patient’s heart.
|
|
|
• Data for MUGA is acquired by
|
dividing the patient’s cardiac cycle into frames ranging from 16-64, depending on software on your system.During each cardiac cycle data continually added together with previous cycles.After a few hundred beats the information gathered provides true story of the cardiac wall motion.
|
|
|
• During a MUGA the computer will record first portion of cardiac cycle into _____________, the second portion of cycle into _____________, and so on until the last frame is reached or next_____________ sensed, which resets the cycle again
|
first frame, second frame, R wave
|
|
|
• “Benefits” of a MUGA compared to 1st pass study (5)
|
1. more time required in recording data for MUGA 2. chambers can be better separated for MUGA 3. count density of images allow better detection of wall motion 4. images can be recorded over longer periods of time without re-injecting patient 5. images recorded in multiple views
|
|
|
• Anterior View of a MUGA is used to examine
|
rt atrial size/motion, tricuspid valve motion, rt ventricular, pulmonary artery size/motion.
|
|
|
• 45-degree LAO of a MUGA is used to
|
separate rt/lt ventricles and see the timing/motion of rt ventricle anterior motion, overall motion, thickening of septum
|
|
|
• Left Lat or LPO of a MUGA is used to
|
view inferior/posterior surfaces of left ventricle, size/motion left ventricle left atrium. If using Spect do 360 degree sample.
|
|
|
• For a MUGA during each cardiac cycle, data are continually added together with _____________. Cumulative info over course of study gives accurate pic of _____________, _____________ frames can be identified based on count # in lt ventricle
|
previous cycles, wall motion, diastolic/systolic
|
|
|
• Patient Preparation for a MUGA (4)
|
get good baseline EKG, 4-8 hrs NPO, no caffeine last 4 hours or cardiac meds.
|
|
|
• How to get a good baseline EKG for a MUGA
|
make sure that the QRS complex is positive, not negative, or you can move the leads to create a positive complex, make sure electrodes have good contact with the skin
|
|
|
• Acquiring MUGA Images anterior view allows the detector to be closer to the patient, maximizing ____. Disadvantage is the _____________ cannot be seen in _____________. Best way to optimize this while keeping detector close is to use _____________ so crystal is pointing ____ on your LAO positioning. Get ____ sec/view
|
resolution, left ventricle, long axis, cranial angulation, caudally, 600
|
|
|
• MUGA data collection can be stopped when
|
either a preset number of counts or a preset number of cycles has been reached.
|
|
|
• For MUGA binding of the Tc99m to the _____________ has to occur and this happens when the Tc99m enters the _____________ and binds to the _____________
|
red blood cell, red cell, beta chain of hemoglobin
|
|
|
• In Vivo RBCs are done by
|
RBCs are tagged inside the patient’s body. Ex:inject cold PYP from kit, wait 20 minutes and inject 20-30mCi Tc99m sodium pertechnetate(TcO4) in opposite arm:note that labeling efficiency is lower but good enough to image.
|
|
|
• What is TcO4
|
Tc99m sodium pertechnetate
|
|
|
• Which method is best: Invivo or Invitro
|
Invitro
|
|
|
• In Vitro RBCs are done by
|
completes the labeling process outside the patient’s body and accomplished by using commercial kits such as UltraTag:start large bore IV to preserve integrity of RBCs:draw 3 ml of patient’s blood into syringe that is heparinized, inject into reaction vial, add contents of syringes I&II, then add Tc99m agent:then re-inject into patient.
|
|
|
• Modified in Vivo/in Vitro RBCs is done by
|
use cold PYP kit and inject patient using straight stick if possible:wait 20 minutes and draw patient’s blood 3-5ml into syringe with 1ml heparin and 25-30mCi Tc99mTcO4:mix for 5-10 minutes and reinject into patient.
|
|
|
• Reasons for Reduced Labeling Efficiencies (7)
|
1. patients with hematocrits(volume of erythrocytes in blood volume) less than 30%. 2. using a chilled syringe for the patient’s blood. 3. Very sick patients because of medication interference. 4. Very sick patients because of plasma changes. 5. Very sick patients because they may have circulating non-red blood cell antibodies that decrease RBC labeling. 6. Length of stannous ion incubation. 7. High doses of steroids.
|
|
|
• What is a normal hematocrit
|
normal is 40-54% for men, 37-47% for women,35-49% for children,49-54% for newborn
|
|
|
• What is the preferred method of RBC labeling if patient on multiple drugs that may diminish labeling
|
Human Serum Albumin
|
|
|
• What is Human Serum Albumin
|
a protein that is a purified product of human blood
|
|
|
• Human Serum Albumin is prepared from commercial kit using _____________
|
Tc99mTcO4
|
|
|
• The disadvantage of Human Serum Albumin is
|
increasing activity to the liver and diffusion into the vasculature.
|
|
|
• How do you calculate stroke volume
|
ED-ES
|
|
|
• Data Processing for MUGA
|
calculate EF as in 1st pass study, calculate SV,( stroke volume ED-ES) Calculate CO (cardiac output, SV x HR)Try to do manual and automatic Efs to compare results for reliability. Get good separation of rt/lt ventricles
|
|
|
• How do you calculate cardiac output
|
stroke volume x heart rate
|
|
|
• Normal Results for a MUGA (6)
|
1. Good blood tag 2. Circulation and heart should present clearly. 3. There should be motion in all heart walls. 4. No defects as described with 1st pass. 5. EF = 50-70% or better. 6. 40-60% rv.
|
|
|
• PET radiopharmaceuticals measure (4)
|
1. Metabolism of glucose 2. Fatty acids 3. Acetate 4. catecholamines.
|
|
|
• PET radiopharmaceuticals can be made for
|
gated blood-pool studies and myocardial perfusion studies.
|
|
|
• Advantage of PET over single-photon imaging (2)
|
better correction of photon attenuation to eliminate false-positive studies, spatial resolution better which gives way to absolute rather than relative imaging.
|
|
|
• Disadvantage of PET
|
High dose.
|
|
|
• Measure of metabolism of glucose is useful in the detection of
|
ischemic, but viable myocardium
|
|
|
• Measure of fatty acids and acetate is useful for the determination of
|
regional oxygen utilization
|
|
|
• Measure of catecholamines is useful to define
|
regional myocardial nerve stimulation
|
|
|
• How to calculate MUGA frames
|
60/HR=X. X/# of frames given=Z. Z x 1000=Answer in miliseconds. PAGE 108
|
|
|
Arteries must be ____% blocked to be picked up on a stress test
|
70
|
|
|
Short axis slices are cut from
|
apex to base (coronal)
|
|
|
Vertical long axis slices are cut from
|
septal to lateral (sagittal)
|
|
|
Horizontal long axis slices are cut from
|
inferior to anterior (transverse/transaxial)
|
|
|
Left coronary artery supplies (LAD AND LCX)
|
LAD – anterior wall and apex. LCX – left lateral wall
|
|
|
Right coronary artery supplies
|
right ventricle and posterior wall
|
|
|
LAD stands for
|
Left Anterior Descending
|
|
|
LCX stands for
|
Left Circumflex Artery
|
|
|
Lead placement: Right Arm (RA)
|
on the right arm avoiding thick muscle
|
|
|
Lead placement: Left Arm (LA)
|
on the left arm avoiding thick muscle
|
|
|
Lead placement: Right Leg (RL)
|
on the right leg, lateral calf muscle
|
|
|
Lead placement: Left Leg (LL)
|
on the left leg, lateral calf muscle
|
|
|
Lead placement: V1
|
In the 4th intercostal space (between 4th and 5th ribs) just to the right of the sternum (breastbone)
|
|
|
Lead placement: V2
|
In the 4th intercostal space (between 4th and 5th ribs) just to the left of the sternum (breastbone)
|
|
|
Lead placement: V3
|
Between leads V2 and V4
|
|
|
Lead placement: V4
|
In the 5th intercostal space (between 5th and 6th rib) in the mid-clavicular line
|
|
|
Lead placement: V5
|
Horizontally even with V4 in the leftanterior axillary line
|
|
|
Lead placement: V6
|
Horizontally even with V4 and V5 in the midaxillary line
|
|
|
The leads of a 12-lead ECG correlate with the walls of the ____, which in turn are related to _____________ that feed each specific region. Coronary artery anatomy is slightly different in each patient, but there is a high correlation between ____ damage patterns and which _____________ is most likely compromised
|
myocardium, coronary arteries, ischemia, coronary artery
|
|
|
Remember that conduction system abnormalities such as _____________ and _____________ can be a sign of an underlying coronary blood supply problem
|
heart blocks, bundle branch blocks
|
|
|
Lead 2, location of infarct and coronary artery involved
|
inferior wall and right ventricle (most common) Right Coronary Artery (RCA)
|
|
|
Lead 3, location of infarct and coronary artery involved
|
inferior wall and right ventricle (most common) Right Coronary Artery (RCA)
|
|
|
Lead aVF, location of infarct and coronary artery involved
|
inferior wall and right ventricle (most common) Right Coronary Artery (RCA)
|
|
|
Lead V1, location of infarct and coronary artery involved
|
Septal wall, Left Anterior Descending (LAD)
|
|
|
Lead V2, location of infarct and coronary artery involved
|
Septal wall, Left Anterior Descending (LAD)
|
|
|
Lead V3, location of infarct and coronary artery involved
|
Anterior wall and apex (most lethal), Left Anterior Descending (LAD)
|
|
|
Lead V4, location of infarct and coronary artery involved
|
Anterior wall and apex (most lethal), Left Anterior Descending (LAD)
|
|
|
Lead 1, location of infarct and coronary artery involved
|
Lateral wall, Left circumflex Artery (LCX)
|
|
|
Lead aVL, location of infarct and coronary artery involved
|
Lateral wall, Left circumflex Artery (LCX)
|
|
|
Lead V5, location of infarct and coronary artery involved
|
Lateral wall, Left circumflex Artery (LCX)
|
|
|
Lead V6, location of infarct and coronary artery involved
|
Lateral wall, Left circumflex Artery (LCX)
|
|
|
Using PET FDG this can be assessed
|
viability
|
|
|
Using PET Rb this can be assessed
|
perfusion
|
|
|
Blood ejected in a single heart beat
|
stroke volume
|
|
|
Arterioles branch to
|
capillaries
|
|
|
Where is oxygen rich blood delivered to via the coronary arteries
|
myocardium
|
|
|
Blood returning to the heart comes from where
|
lungs
|
|
|
Where does the ventricular systole impulse come from
|
Bundle of His
|
|
|
What cell causes scaring
|
fibroblasts
|
|
|
Branch structure of the arteries start with
|
arterioles
|
|
|
Ventricular relaxation is
|
diastole
|
|
|
Ventricular contraction is
|
systole
|
|
|
Heart valves prevent regurgitation from atria to
|
ventricles
|
|
|
Blood returning to the heart goes to what chamber
|
atria
|
|
|
A-fib shows no ____ wave. Is always ____. Shows quiver of the ____. Can be fixed with _____________
|
P, irregular, atria, bolus of adenosine
|
|
|
V-tach and V-fib are
|
shockable rhythms
|
|
|
What is sinus tachycardia and how can it be fixed
|
very fast normal rhythm. Bolus of adenosine
|
|
|
What does sinus mean
|
normal
|
|
|
2 PVC and a regular rhythm is called
|
bigeminy
|
|
|
3 PVC and a regular rhythm is called
|
trigeminy
|
|
|
PVC means
|
premature ventricular contraction
|
|
|
What is another name for a bullseye
|
polar plot
|
|
|
Before using these two stress agents, ask the patient about asthma
|
dipyridamole and adenosine
|
|
|
Tl-201 is useful because
|
it redistributes and shows ischemia
|
|
|
This is permanent damage ____ and this is reversible ____
|
infarct, ischemia
|
|
|
CABG stands for
|
coronary artery bypass graft
|
|
|
Breast attenuation can be seen on which views
|
anterior and lateral
|
|
|
Diaphragmatic attenuation can be seen on which views how to get rid of the attenuation
|
inferior. Place patient in prone position
|
|
|
The cardiac conduction pathway is made up of 5 elements
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1. Sino-atrial node (SA) 2. Atrio-ventricular node (AV) 3. Bundle of His 4. The left and right bundle branches 5. Purkinje fibers
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The SA node is the natural ____ of the heart
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pacemaker
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You may have heard of permanent _____________ and temporary _____________ which are used when the ____ has ceased to function properly
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pacemakers (PPMs), pacing wires (TPWs), SA node
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The SA node releases electrical stimuli at a regular rate, the rate is dictated by
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the needs of the body
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Each SA node stimulus passes through the myocardial cells of the ____ creating a wave of contradiction which spreads rapidly through both ____
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atria, atria
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