Radiographic Pathology For Technologists Ch. 8

Front 1

Anatomy of the heart

Back 1

Two upper chambers = left and right atria
Two lower chambers = left and right ventricles
Layers of the heart from inside to out - Endocardium (valves), Myocardium (thickest part receives blood from the right and left coronary arteries from the aorta during diastole(while the heart is relaxed)), Epicardium (Protective coating)
Pericardial Sac -has small amounts of fluid to reduce friction

Front 2

Physiology of the Heart

Back 2

1. Right atrium receives deoxgynated blood from vena cava
2. Goes to right ventricle
3. To the lungs, 60% right and 40% left
4. Gas exchange at the capillary alveolar level
5. Oxygenated blood returns to the left atrium via 4 pulmonary veins
6. Then to the left ventricle
7. Finally, to the system

Front 3

Cardiac Cycle

Back 3

Systole (contraction) then Diastole (relaxation)
Pace Maker of the Heart is the Sinoatrial (SA) Node located in the upper portion of the right atrium

Front 4

Imaging considerations

Back 4

Chest xrays are mostly for size and shape of heart. Also, can demonstrate the greater vessels and any vascular changes
Controllable Factors: patient posture, degree of inspiration, positioning, geometric factors and technique
Uncontrollabe factors: patient habitus, abnormal physiology(scoliosis and pectus excavatum) and pathological conditions (pneumothorax or pulmonary emphysema)

Front 5

Cardiac Series

Back 5

Involves a series of xrays taken while the patient swallows contrast media (usually barium).
Evaluation of the esophagus demonstrates heart size

Front 6

Ciculatory Vessels

Back 6

Arteries - Carry blood away from heart
3 layers (outer to inner) adventitia, media, intima
Lumen - Internal tubular structure of the vessel
Veins - Carry blood to the heart
Capillaries - Microscopic vessels that connect arteries and veins

Front 7

More considerations

Back 7

If pt is semirecumbent or recumbent the heart appears to be enlarged b/c abdominal organs push the diaphragm up into the thoracic cavity
Poor inspiriation can disort heart shap/size
Must see at least 10 posterior ribs with in lung field
72in SID reduces heart maginification to an approx. 10%
Annode heel effect - place anode over apical region and cathode toward base

Front 8

Transposition of Greater Vessels

Back 8

An anomoly in which the aorta arises from the right ventricle instead of the left ventricle and the pulmonary trunk arises from the left ventricle instead of the right ventricle, Requires a shunt betwen the two sides of the heart for survival.
CXR shows a narrow mediastinum b/c the vessels are superimposed and the main pulmonary trunk is not in the usual place

Front 9

Congenital and Hereditary Diseases -
Fetal Circulation

Back 9

Maternal blood supplies the fetus with oxygen and nutrients and carries away wastes
Diffuse through placental membrane
Carried to fetal body through umbilical blood vessels
Concenctration of hemoglobin is 50% greater than maternal blood
Carries 20-30% more oxygen

Front 10

Congenital and Hereditary Diseases - Heart Murmur

Back 10

Most often caused by defective heart valves.
A stenotic heart valve has a smaller-than-normal opening and can't open completely and or close completely, blood regurgitates back.
Murmurs can also be cause by conditions such as pregnancy, fever, thyrotoxicosis(disease from overactive thyroid gland) or anemia.
Diastolic murmer-occurs when heart muscle relax between beats
Systolic Murmer- Opposite
Systolic murmers are graded by intensity (loudness) 1-6.

Front 11

Congenital and Hereditary Diseases - Patent Ductus Arteriosus (PDA)

Back 11

PDA is a heart problem that occurs soon after birth in some. In PDA, there is abnormal ciculation of blood between two of the major arteries near the heart. The ductus arteriousus remains open(patent) between the aorta and pulmonary artery after birth. Allows blood to flow directly from the aorta into the pulmonary artery which increases blood pressure in lung arteries.
Chest Xray demonstrates cardiomegaly with prominence of the left side.

Front 12

Congenital and Hereditary Diseases - Coarctation of the Aorta

Back 12

Malformation of the biggest blood vessel in the body(the aorta). Its a narrowing of the aorta. Occurs most commonly in a short segment just beyond where the arteries to the head and arms take off. Its called the "juxta-ductal" part of the aorta or the part where the ductus arteriosus attaches.
CXR shows two bulges of the aorta near arch. One below and one above stenosis.
RIB NOTCHING is another indication. Erosion of bone along lower rib margins due to anastomatoic vessels

Front 13

Congenital and Hereditary Diseases - Septal Defects

Back 13

The septum is the wall the separates the heart's left and right sides. Septal defects are sometimes called a "hole" in the heart.
Atrial Septal defects are the most common and occure twice as much in girls.
Radiographically, Right atrium and ventricle are enlarged, resulting in cardiomegaly.
A defect between the two lower ventricles is called a "Ventricular Septal Defect" (VSD).
Oxygenated blood is forced from the left side to the right and then back into the lungs even though its already been give oxygen. Leads to increased work for the heart which may enlarge it. Also causes higher blood pressure in lungs. May damage vessels
Radiographically, left atrium and ventrical are enlarged, resulting in cardiomegaly
VSD are most serious b/c of the pressure differences between the two ventricles
If the opening is small then it doesn't damage heart and is heard as a loud murmur.

Front 14

Congenital and Hereditary Diseases - Tetralogy of Fallot

Back 14

Four key feature: A VSD and many levels of obstruction from the right ventricle to the lungs (pulmonary Stenosis), right ventricle develops thickened muscle. Because the aorta overrides the VSD and there's Pulmonary Stenosis, blood from both venticles (oxygen rich and poor) is pumped into the body.
Sometimes the pulmonary valve is completely obstructed (pulmonary atresia).
Infants and children with unrepaired tetraolgy of Fallot are often blue(cyanotic).
CXR shows enlargement of right ventricle and appears as a boot-shaped shadow.

Front 15

Valvular Disease -
Rheumatic Fever

Back 15

Is a serious inflammatory condition that can affect many parts of your body - heart, joins, nervous system and skin.
Most common in ages 6-15.
Twice as common in females.
Symptoms appear 5 weeks after untreated strep throat infection. Most cases don't lead to rheumatic fever.
May affect heart valves(rheumatic Carditis) and interfere with normal blood flow through heart.
No Cure!
Prevented by proper treatment of strep.

Front 16

Valvular Disease -
Valvular Stenosis

Back 16

Name given to any dysfunction or abnormality of one or more of the heart's 4 valves, including the mitral and aortic valve on the left side, and the tricuspid and pulmonic valve on the right side.
Most cases of disorder involve the aortic valve (63%) and mitral valve (14%)
Valvular heart disease may pose greater risk to pregnant women due to increased cardiac output during pregnancy.

Front 17

Valvular Disease -
Congestive Heart Failure (CHF)

Back 17

CHF ,aka heart failure, is a condition in which the heart can't pump enough blood to the body's other organs.
Cause by: narrowed arteriesthat supply blood to the heart muscle( coronary artery disease),
past heart attack,
High blood pressure,
Heart valve disease due to past rheumatic fever,
primary disease of the heart muscle itself(cardiomyopathy),
congenital heart defects,
infection of the heart valves and/or heart muscle itself (endocarditis and/or mycarditis)
Slow blood flow caues congestion in tissues. Edema often results in legs and ankles and sometimes in lungs interfering breathing.
Affects kidneys' ability to dispose of sodium and water. The retained water incrases edema.
Leftsided failure - xray shows cardiomegaly and the hilar region is congested(increased vascular markings)
Right side failure - Not as common. Xrays show right atrium and ventricle enlarged.

Front 18

Valvular Disease -
Cor Pulmonale

Back 18

Failure of the right side of the heart cause by prolonged high blood pressure in the pulmonary artery and right ventricle of the heart.
Normally, the left side of the heart produces a higher level of pressure. The right side pumps blood through the lungs under much lower pressure. So its not able to tolerate sustained high pressure (pulmonary hypertension).
Almost any chronic lung disease or condition causing prolonged low blood oxygen can lead to cor pulmonale.
XRAYs show englargement of a right ventricle and proximal pulmonary artery

Front 19

Degenerative Diseases -
Atherosclerosis

Back 19

Type of arteriosclerosis. Athero-gruel or paste and sclerosis - hardness.
Term for the process of fatty substances, cholesterol, cellular waste, calcium and fibrin (a clotting material in the blood). Builds up in the form of "Plaque".
Two things can happen:
1. Bleeding into the plaque
2. Formation of blood clot on plaques surface

Front 20

Degenerative Diseases -
Coronary Artery Disease (CAD)

Back 20

CAD occurs when the arteries that supply bloodto the heart muscle (the coronary arteries) become hardened and narrowed.
Narrowing causes reduced blood flow and oxygen to muscle.
Can result in: Angina (occurs when heart doesn't get enough blood)
Heart Attack (occurs when blood clot forms at site of plaque in coronary artery and suddenly cuts of blood supply.
Infarct -area of ischemic necrosis

Front 21

Degenerative Diseases -
Myocardial Infarction (MI)

Back 21

MI is most commonly caused by an acute thrombus of the coronary arteries and primarly effects the left ventricle. If blood flow isn't restored in 20-40 min, irreversible death of muscle begins. 25% of victims die before reaching hospital

Front 22

Degenerative Diseases -
Aneurysm

Back 22

A balloon like bulge in an artery and can form in arteries of all sizes. 3 types:
Saccular - localized bulge on one side of the arterial wall. Usually located in a cerebral artery.
Fusiform - Bulging includes entire circumference of artery. Found in distal abdominal aorta.
Dissecting - Results when intima tears adn allows blood to flow within the vessel wall, thus forming an intramural hematoma. Mimcs hear attack symptoms
Majority of aneurysms occur in abdominal aorta below level of renal arteries

Front 23

Degenerative Diseases -
Venous Thrombosis

Back 23

Formation of blood clots within a vein. Commonly form in the veins of the lower extremities. Clot can break off and travel through the blood stream (emobize). A resulting embolus can lodge in the brain, lungs or heart.
Risks include:
Prolonged sitting/bed rest or immobilization
Recent surgery or trauma
fractures,
childbirth within last 6 months
and use of estrogen or birth control pills

Front 24

Phlebitisis

Back 24

General term for inflammation of a vein. Very often followed by a thrombus.
Condition is called thrombophlebitis or venous thrombosis
Two types: a superficial condition that is painful but not life threatening and deep thrombophlebitis involving emboli.

Front 25

Pulmonary Embolism

Back 25

Blood clot lodged in pulmonary artery. Prolonged bed rest and inactivity increase the risk. Symptoms include onset of coughing, acute shortness of breath, and chest pain. Half of survivers have another episode.