Cardiac

Question 1

Name the layers of the cardiac muscle wall from inside to out

Answer 1

1. Endocardium
2. Myocardium
3. Pericardium (serous pericardium, visceral layer, epicardium; pericardial space; Serous pericardium parietal layer; fibrous pericardium)

Question 2

What are the main coronary arteries?

Answer 2

1. Right Coronary Artery

2. Left Coronary Artery (Left Circumflex; Left anterior descending)

Question 3

Name and describe the layers of the vessel walls from the inside out?

Answer 3

1. tunica interna (or tunica intima): endothelium, selectively permeable, secretes chemical to constrict/dilate, repels blood cells and platelets.
2. tunica media: smooth muscle, strengthens vessel
3. tunica externa (or tunica adventitia): loose connective tissue, merges with other organs, anchors vessel

Question 4

What is the approximate composition of blood?

Answer 4

Plasma- approx 50-55%
RBC’s- approx 40-45%
WBC’s- 1%

Question 5

What is Cardiac Output? How is it calculated?

Answer 5

• Volume of blood pumped out of heart in one minute (L/min)

- CO = Stroke volume x Heart Rate

Question 6

What is ejection fraction? What is the normal range?

Answer 6

Ejection fraction is the percent of blood which has filled the ventricle which is ejected by contraction.

Normal ejection fraction is 55-75%