Usmle First Aid Cardiology

Front 1

What are the three structures located inside the carotid sheath?

Back 1

The internal jugular Vein, the common carotid Artery, and the vagus Nerve (remember the Mnemonic VAN)

Front 2

What is the spatial relationship among the three structures located inside the carotid sheath?

Back 2

The internal jugular vein is lateral, the common carotid artery is medial, and the vagus nerve is posterior

Front 3

What is the most posterior part of the heart?

Back 3

The left atrium

Front 4

What symptoms will be caused by enlargement of the left atrium and compression of nearby stuctures?

Back 4

Dysphagia and hoarseness

Front 5

Why does enlargement of the left atrium cause dysphagia?

Back 5

Because it causes compression of the esophageal nerve

Front 6

Compression of the ______ ______ nerve, a branch of the _____ nerve causes hoarseness.

Back 6

Recurrent laryngeal; vagus

Front 7

In what part of the cardiac cycle do the coronary arteries fill?

Back 7

Diastole

Front 8

Which coronary artery is most commonly occluded?

Back 8

The left anterior descending artery
widow maker

Front 9

What part of the heart is supplied by the left anterior descending artery?

Back 9

The anterior interventricular septum
and apex

Front 10

In most cases, the sinoatrial and atrioventricular nodes are supplied by which coronary artery?

Back 10

The right coronary artery

Front 11

The right coronary artery supplies the posterior septum via which coronary artery?

Back 11

The posterior descending artery
(in a right dominant heart- 80%)

Front 12

When the right coronary artery supplies the inferior portion of the left ventricle via the posterior descending artery, what type of dominance is this?

Back 12

Right dominance

Front 13

A patient has a myocardial infarction that damages the anterior interventricular septum. Which coronary artery was occluded?

Back 13

The left anterior descending artery

Front 14

The posterior descending artery that supplies the posterior septum arises from the circumflex artery in _____ (20%/50%/80%) of cases.

Back 14

20%

Front 15

Which coronary artery supplies the posterior left ventricle?

Back 15

Circumflex artery

Front 16

The right coronary artery supplies the posterior septum via which coronary artery?

Back 16

The posterior descending artery
(in a right dominant heart- 80%)

Front 17

When the right coronary artery supplies the inferior portion of the left ventricle via the posterior descending artery, what type of dominance is this?

Back 17

Right dominance

Front 18

A patient has a myocardial infarction that damages the anterior interventricular septum. Which coronary artery was occluded?

Back 18

The left anterior descending artery

Front 19

The posterior descending artery that supplies the posterior septum arises from the circumflex artery in _____ (20%/50%/80%) of cases.

Back 19

20%

Front 20

Which coronary artery supplies the posterior left ventricle?

Back 20

Circumflex artery

Front 21

Which coronary artery supplies the apex and anterior interventricular septum?

Back 21

Left anterior descending artery

Front 22

Which coronary artery supplies the posterior septum?

Back 22

Posterior descending/interventricular artery

Front 23

Which coronary artery supplies the right ventricle?

Back 23

Acute marginal artery (from the right coronary artery)

Front 24

When the posterior descending artery arises from the circumflex, what type of dominance is this?

Back 24

Left dominance

Front 25

With regard to auscultation of the heart, in what area is the murmur of aortic stenosis best heard?

Back 25

The aortic area (ie, the right sternal border and the second intercostal space)

Front 26

In which phase of the cardiac cycle is the murmur of aortic stenosis best heard?

Back 26

Systolic

Front 27

With regard to auscultation of the heart, in what area is the murmur of pulmonic stenosis best heard?

Back 27

The pulmonic area (ie, the left sternal border and the second intercostal space)

Front 28

With regard to auscultation of the heart, in what area is the murmur of a ventricular septal defect best heard?

Back 28

The tricuspid area (ie, the left sternal border and the fourth intercostal space)

Front 29

With regard to auscultation of the heart, in what area is the murmur of tricuspid regurgitation best heard?

Back 29

The tricuspid area (ie, the left sternal border and the fourth intercostal space)

Front 30

With regard to auscultation of the heart, in what area is the murmur of tricuspid stenosis best heard?

Back 30

The tricuspid area (ie, the left sternal border and the fourth intercostal space)

Front 31

In which phase of the cardiac cycle is the murmur of tricuspid stenosis best heard?

Back 31

diastole

Front 32

With regard to auscultation of the heart, in what area is the murmur of an atrial septal defect best heard?

Back 32

The tricuspid area (ie, the left sternal border and the fourth intercostal space)

Front 33

With regard to auscultation of the heart, in what area is the murmur of mitral stenosis best heard?

Back 33

The mitral area (ie, the midclavicular line and the fifth intercostal space)

Front 34

In which phase of the cardiac cycle is the murmur of mitral stenosis best heard?

Back 34

diastole

Front 35

With regard to auscultation of the heart, in what area is the murmur of mitral regurgitation best heard?

Back 35

The mitral area (ie, the midclavicular line and the fifth intercostal space)

Front 36

In which phase of the cardiac cycle is the murmur of mitral regurgitation best heard?

Back 36

Systolic

Front 37

With regard to auscultation of the heart, in what area is the murmur of aortic regurgitation best heard?

Back 37

The left sternal border (generally)

Front 38

In which phase of the cardiac cycle is the murmur of aortic regurgitation best heard?

Back 38

diastole

Front 39

With regard to the auscultation of the heart, in what area is the murmur of pulmonic regurgitation best heard?

Back 39

The left sternal border (generally)

Front 40

In which phase of the cardiac cycle is the murmur of pulmonic regurgitation best heard?

Back 40

diastole

Front 41

With regard to auscultation of the heart, in what area are flow murmurs best heard?

Back 41

The second intercostal space and both the left and right sternal borders
-since this is where aortic and pulmonic valves are

Front 42

In which phase of the cardiac cycle are flow murmurs heard?

Back 42

systole

Front 43

A murmur of hypertrophic cardiomyopathy occurs in the ______ phase of the cardiac cycle.

Back 43

systole

Front 44

With regard to auscultation of the heart, in what area is the murmur of hypertrophic cardiomyopathy best heard?

Back 44

The left sternal border (generally)

Front 45

Atrial septal defects can best be auscultated over the _____ (aortic/pulmonic / tricuspid/mitral) area of the heart.

Back 45

tricuspid

Front 46

Pulmonic flow murmurs and diastolic rumbles are commonly associated with which cardiac defect?

Back 46

atrial septal defects

Front 47

Atrial septal defects progress to louder diastolic murmurs due to pulmonic regurgitation from dilatation of which artery?

Back 47

pulmonary artery

Front 48

Cardiac output = stroke volume x _____ _____.

Back 48

Heart rate

Front 49

What does Fick's principle measure?

Back 49

Cardiac output

Front 50

What is the equation of Fick's principle?

Back 50

Cardiac output = rate of oxygen consumption / (arterial oxygen content - venous oxygen content)

Front 51

Stroke volume × heart rate = _____ _____.

Back 51

Cardiac output

Front 52

Mean arterial pressure = _____ _____ × total peripheral resistance.

Back 52

Cardiac output

Front 53

Cardiac output = rate of oxygen consumption / (arterial oxygen content - _____ _____ _____).

Back 53

Venous oxygen content (the Fick principle)

Front 54

Mean arterial pressure = cardiac output × _____ _____ _____.

Back 54

Total peripheral resistance

Front 55

Cardiac output = _____ _____ _____ _____ / (arterial oxygen content - venous oxygen content).

Back 55

Rate of oxygen consumption

Front 56

_____ _____ _____ = cardiac output × total peripheral resistance.

Back 56

mean arterial pressure

Front 57

_____ _____ _____ = (1/3) systolic pressure + (2/3) diastolic pressure.

Back 57

mean arterial pressure

Front 58

_____ _____ = systolic pressure - diastolic pressure.

Back 58

pulse pressure (increased with aortic regurgitation)

Front 59

What is pulse pressure proportional to?

Back 59

stroke volume

Front 60

Stroke volume = end-diastolic volume - _____ _____.

Back 60

End-systolic volume

Front 61

During exercise, cardiac output increases initially as a result of a(n) ______ (increase/decrease) in stroke volume.

Back 61

increase-- note that SV increases before HR does during exercise!!!

Front 62

After prolonged exercise, cardiac output increases as a result of an increase in _____ ____.

Back 62

heart rate

Front 63

If the heart rate is too high, _____ filling is incomplete, and cardiac output decreases.

Back 63

diastolic

Front 64

What are the three variables that affect stroke volume?

Back 64

Contractility, Afterload, and Preload (remember the mnemonic SV CAP)

Front 65

What happens to stroke volume when there is an increase in contractility?

Back 65

Stroke volume increases

Front 66

How does digitalis affect contractility (and thus stroke volume)?

Back 66

Digitalis increases contractility (by trapping Ca2+ inside cells)

Front 67

By what mechanism does digitalis cause an increase in contractility (and thus stroke volume) ?

Back 67

Digitalis increases intracellular sodium, which results in an increase in intracellular calcium, strengthening contraction (no gradient for Na+/Ca2+ exchanger)--blocks Na/K ATPase pump

Front 68

What happens to stroke volume when there is a decrease in afterload?

Back 68

Stroke volume increases

Front 69

How does acidosis affect contractility?

Back 69

Acidosis decreases contractility
-don't want to drive up metabolic demand when youre already acidotic.

Front 70

How does β1 blockade affect contractility and stroke volume?

Back 70

β1 blockade decreases contractility and stroke volume

Front 71

What cardiac output variable is increased when there is an increase in preload?

Back 71

stroke volume

Front 72

How does hypoxia/hypercapnia affect contractility and stroke volume?

Back 72

Hypoxia and hypercapnia decrease contractility and stroke volume-- dont have the materials needed to sustain high output

Front 73

Does anxiety increase or decrease stroke volume?

Back 73

Increase

Front 74

How do catecholamines affect contractility (and thus stroke volume)?

Back 74

Catecholamines increase contractility

Front 75

By what mechanism do catecholamines cause an increase in contractility?

Back 75

By increasing the activity of the calcium pump in the sarcoplasmic reticulum

Front 76

How do calcium channel blockers affect contractility and stroke volume?

Back 76

Calcium channel blockers decrease contractility and stroke volume

Front 77

How does heart failure affect contractility and stroke volume?

Back 77

Heart failure decreases contractility and stroke volume

Front 78

How does decreasing extracellular sodium affect contractility (and thus stroke volume)?

Back 78

A decrease in extracellular sodium increases contractility (less gradient to pump Ca2= out through the Na/Ca2+ exchanger)

Front 79

By what mechanism does decreasing extracellular sodium cause an increase in contractility (and thus stroke volume)?

Back 79

By decreasing the activity of the sodium/calcium ion exchanger

Front 80

Does pregnancy increase or decrease stroke volume?

Back 80

increase

Front 81

By what mechanism does increasing heart size increase myocardial oxygen demand?

Back 81

By causing an increase in wall tension

Front 82

Does exercise increase or decrease stroke volume?

Back 82

increase

Front 83

Does increasing contractility increase or decrease myocardial oxygen demand?

Back 83

increase

Front 84

Contractility and stroke volume _____ (increase/decrease) with non-dihydropyridine calcium channel blockers such as verapamil.

Back 84

decrease

Front 85

Does increasing afterload increase or decrease myocardial oxygen demand?

Back 85

Increase

Front 86

Ventricular end-diastolic volume = _____.

Back 86

preload

Front 87

_____ = Mean arterial pressure.

Back 87

Afterload

Front 88

Do venous dilators decrease preload or afterload?

Back 88

preload

Front 89

Do vasodilators decrease preload or afterload?

Back 89

afterload

Front 90

Does exercise increase or decrease preload?

Back 90

increase

Front 91

Does sympathetic stimulation increase or decrease preload?

Back 91

increase

Front 92

Afterload is proportional to _____ _____.

Back 92

peripheral resistance

Front 93

The Starling curve shows that the force of contraction is proportional to what?

Back 93

The preload or the initial length of the cardiac muscle fiber

Front 94

On the Starling curve, the x-axis is represented by two variables: ______ (preload/afterload) and _____ _____-_____ _____ (ventricular end-diastiolic volume/ventricular end-systolic volume).

Back 94

Preload; ventricular end-diastolic volume
(which are the same thing)

Front 95

On the Starling curve, the y-axis is represented by two variables: _____ _____ and _____ _____.

Back 95

Cardiac output; stroke volume

Front 96

True or false: Congestive heart failure causes a decrease in slope of the Starling curve.

Back 96

true

Front 97

True or false: Exercise causes the Starling curve to move to the right and decrease in slope.

Back 97

False; exercise causes the Starling curve to move to the left and increase in slope

Front 98

Does digitalis increase or decrease contractile strength?

Back 98

Increase