Week 3 High-Yield Questions, Answers,
& Rationales 2026/2027 Update
Question 1: Cardiovascular Hemodynamics - Preload and
Afterload
Which physiological factor represents the resistance that the left
ventricle must overcome to eject blood during systole?
A. Preload
B. Afterload
C. Myocardial contractility
D. Stroke volume
Correct Answer: B. Afterload.
Explanation: Afterload is the resistance or impedance to
ventricular ejection that the heart must overcome to open the
aortic valve and push blood into the systemic circulation. It is
primarily determined by systemic vascular resistance (SVR) and
arterial blood pressure. Preload, by contrast, refers to the end-
diastolic volume/pressure that stretches the ventricle before
contraction.
Question 2: Heart Failure - Systolic vs. Diastolic Dysfunction
,A patient is diagnosed with heart failure with preserved ejection
fraction (HFpEF), previously known as diastolic heart failure.
What is the fundamental underlying pathophysiology of
HFpEF?
A. Inability of the left ventricle to contract forcefully
enough to eject a normal volume of blood during systole,
resulting in a low ejection fraction ($<40\%$).
B. Impaired ventricular relaxation and decreased
ventricular compliance during diastole, resulting in
inadequate ventricular filling despite a normal ejection
fraction.
C. Massive valvular regurgitation caused by acute rupture
of the chordae tendineae.
D. Severe bradycardia leading to inadequate cardiac output.
Correct Answer: B. Impaired ventricular relaxation and
decreased ventricular compliance during diastole, resulting
in inadequate ventricular filling despite a normal ejection
fraction.
Explanation: HFpEF is characterized by stiff, non-compliant
ventricular myocardium that resists normal filling during
diastole. While the heart can still squeeze well, the elevated
filling pressures back up into the pulmonary circulation, causing
pulmonary congestion.
Question 3: Valvular Heart Disorders - Aortic Stenosis
An 75-year-old patient presents with exertional dyspnea,
syncope, and a harsh systolic ejection murmur heard best at the
second right intercostal space radiating to the carotids. Which
, condition is the most common cause of this valvular disorder in
developed countries?
A. Rheumatic fever resulting in leaflet fusion
B. Age-related calcific aortic stenosis (degenerative
calcification)
C. Infective endocarditis with vegetation formation
D. Congenital bicuspid aortic valve failure
Correct Answer: B. Age-related calcific aortic stenosis
(degenerative calcification).
Explanation: In developed nations, degenerative calcific aortic
stenosis is the most common cause of aortic valve obstruction in
older adults. Decades of mechanical stress lead to calcium
deposition on the aortic leaflets, restricting their opening and
obstructing left ventricular outflow.
Question 4: Valvular Heart Disorders - Mitral Regurgitation
What is the primary hemodynamic consequence of chronic,
severe mitral regurgitation on the left side of the heart?
A. Volume overload and eccentric hypertrophy of both the
left atrium and left ventricle.
B. Pressure overload and concentric hypertrophy of the
right ventricle.
C. Immediate collapse of the aortic arch pressure gradient.
D. Atrophy of the left atrium due to decreased filling.
Correct Answer: A. Volume overload and eccentric
hypertrophy of both the left atrium and left ventricle.