Rt 10 Ch 10

Front 1

Anatomy of the heart

Back 1

Heart is hollow, four chambered, muscular roughly fist sized.

Lies just behind the sternum, two thirds lied to left, between the second through the six ribs.

Surface grooves sulci mark the boundaries of the heart chambers

Front 2

Pericardium

Back 2

Double walled sack and closing heart

Front 3

Pericardium structure

Back 3

Fibrous pericardium tough loose fitting and inelastic sack surrounding the heart

Serous pericardium :consisting of two layers. Parietal layer - inner lining of the fibrous pericardium. the Visceral layer of epicardium covering the outer surface of the heart and great vessels

Front 4

Pericardial fluid

Back 4

Fin layer of fluid separating parietal and visceral pericardium. Helps minimize friction during contraction and expansion

Front 5

Pericardial effusion

Back 5

Abnormal amount of accumulating fluid between layers

Front 6

Cardiac tamponade

Back 6

Large pericardial effusion may affect pumping function. Can cause serious drop in blood flow to body. May ultimately lead to shock and death

Front 7

Pericarditis

Back 7

Inflammation of pericardium

Front 8

Heart wall is composed of three layers

Back 8

Outer: epicardium

Middle: myocardium comprises bulk of heart and is composed of muscle tissue

Inner: endocardium- from thin continuous tissue with blood vessels

Front 9

Heart forms four muscular chambers

Back 9

Upper chambers: right and left atria

Lower chambers: right and left ventricles - responsible for forward movement of blood

Front 10

Semilunar valves

Back 10

Consist of three half-moon shaped cusps separate ventricles from there arterial outflow

Situated at ventricle exits to out flow tracks (aterial trunks) - pulmonary valve lies between right ventricle and pulmonary artery

Aortic valve lies between left ventricle and aorta

Front 11

Semilunar valves

Back 11

Systole (cardiac contraction) valves open, allowing ventricular ejection into arteries ( pulmonary artery and aorta)

Diastole - valves close preventing backflow of blood into ventricles, regurgitation and stenosis-pathologic narrowing or constriction of outlet

Front 12

Coronary circulation

Back 12

Heart's high metabolic demands require an extensive circulatory system. The heart requires more blood flow per gram of tissue weight than any other organ besides kidneys

Front 13

Coronary circulation

Back 13

Two main coronary artery's rides in the root of the aorta:

Left coronary artery, right coronary artery.

Front 14

Coronary artery pressure becomes higher than aortic pressure during systole

Back 14

Prevents flow of blood into coronaries, diastole is when coronary blood flow occurs thus, diastolic pressure is very important

Front 15

Left coronary artery's

Back 15

Position underneath aortic semi lunar valve

Front 16

Left coronary artery he branches into

Back 16

Left anterior descending courses between left and right ventricles - circumflex courses around left side of heart between left atrium and left atrium

Front 17

Apex of the heart

Back 17

Is formed by the tip of the left ventricle and lies just above the diaphragm at the level of the fifth intercostal space to the left

Front 18

Cardiac tamponade

Back 18

A large pericardial effusion may affect the pumping function of the heart

Front 19

Two chambers of heart or ventricles

Back 19

Make up the bulk of the heart muscle mass and do most of the pumping that circulates the blood.the mass of the left ventricle is normally approx two thirds larger than the mass of the right ventricle and has a spherical appearance when viewed across anteriorly

Front 20

Two main coronary arteries a left (2) and right (1) arise from the root of the aorta

Back 20

N/a

Front 21

Partial Obstruction of a coronary artery may lead to tissue ischemia ( decreased oxygen supply)

Back 21

N/a

Front 22

Inherent rhythmicity or automaticity is the unique ability of cardiac muscle to initiate a spontaneous electrical impulse

Back 22

N/a

Front 23

Contractility

Back 23

In response to an electrical impulse, is the primary function of the myocardium

Front 24

Frank sterling law

Back 24

The more a cardiac fiber is stretched (up to point) the greater the tension it generates when contracted

Front 25

Coordination is achieved by integrating the functions of the heart and vascular system. The goal is to maintain adequate perfusion to all tissue according to their needs.

Back 25

N/a

Front 26

Central control of blood flow is achieved primarily by the sympathetic division of the autonomic nervous

Back 26

N/a

Front 27

Smooth muscle relaxation and vessel dilation occur as a result of stimulation of either cholinergic or specialized beta adrenergic receptors.

Back 27

N/a

Front 28

Cardiac output

Back 28

The total amount of blood pumped by the heart per minute. CO is simply the product of the HR and the volume ejected by the left ventricle on each contraction or stoke volume- CO = HR X SV

Normal resting CO is 5 L/min

Front 29

SV is affected primarily by intrinsic control of three factors:

Back 29

1) preload

2) afterload

3) contractility

Front 30

Normal ejection fraction(EF) or proportion of the EDV ejected on each stroke , can be calculated as follows

Normal ejection- 70ml

EDV - 110- 120

Back 30

EF = SV X 100

EDV

= 70 ml x 100

110

= 64%

Front 31

The concept of tension or force and filling volumes are often described I term of preload and afterload

Back 31

N/a

Front 32

Preload may be calculated in a manner that recognizes the force that stretches the resting cardiac muscle to a given length before contraction

Back 32

N/a

Front 33

Parasympathetic stimulation exerts a negative inotropic effect. Profound hypoxia and acidosis impair myocardial function and decrease cardiac contractility

Back 33

N/a

Front 34

When the pumping efficiency of the heart is so low that CO is inadequate to meet tissue needs the heart is said to be

Back 34

Congestive heart failure ( CHF)

Front 35

Stimulation of the vasoconstrictor area within the medulla causes vasoconstriction and increased vascular resistance. Stimulation of this center increases HR by increasing sympathetic discharge to the SA and AV nodes of the heart.

Back 35

N/a

Front 36

Two types of peripheral cardiovascular receptors

Back 36

Baroreceptors or stretch receptors and chemoreceptors. Baroreceptors respond to pressure changes, whereas chemoreceptors respond to changes in blood chemistry

Front 37

The major cardiovascular effects of chemoreceptor stimulation are vasoconstriction and increased HR

Back 37

N/a

Front 38

Dicrotic notch

Back 38

Is caused by the elastic recoil of the arteries. This recoil provides the extra "push" that helps maintain the pressure created by the ventricles.

Front 39

With in a few hundredths of a second after depolarization, the ventricles begin to contract. Closure of the mitral valve occurs first, followed immediately by closure of the tricuspid valve.

Back 39

N/a