NEET Biology: Disorders of circulatory system-Heart failure Practice Questions

Correct answer: D — Regulation of systemic blood pressure

Heart failure is fundamentally a failure of the myocardium (heart muscle) to pump blood effectively to meet the body's metabolic demands, which impacts systemic blood pressure regulation.

Correct answer: C — Lungs and peripheral tissues

When the heart fails, blood backs up, causing fluid accumulation in the lungs (pulmonary congestion) and peripheral tissues, leading to edema.

Correct answer: B — Increased

When the left ventricle fails, blood backs up into the pulmonary circulation, causing pulmonary congestion and increased pulmonary pressures, which often leads to increased pulmonary vascular resistance as part of the compensation/pathology.

Correct answer: B — Inability of the heart to pump blood effectively

Heart failure is fundamentally a state where the heart muscle is unable to pump blood effectively to meet the body's metabolic demands.

Correct answer: A — Decreased blood flow to the peripheral tissues

Reduced cardiac output means less blood is pumped to the body per minute, directly resulting in decreased blood flow to the peripheral tissues.

Correct answer: B — Increased cardiac output

Chronic hypertension forces the heart to work harder, leading to increased workload. If the heart cannot cope, it results in heart failure, often manifesting as an attempt to maintain cardiac output through increased effort.

Correct answer: B — Increased myocardial oxygen demand

High preload means the ventricle is filled with excessive blood (increased end-diastolic volume). This increases the workload and myocardial oxygen demand on the failing heart.

Correct answer: D — Shortness of breath (Dyspnea)

Shortness of breath (Dyspnea) is a hallmark symptom of heart failure, often due to fluid backup in the lungs (pulmonary congestion).

Correct answer: A — Volume Overload Failure

Diastolic heart failure relates to the heart's inability to relax and fill properly with blood, leading to symptoms related to fluid accumulation.

Correct answer: C — Increased pulmonary artery pressure

When left ventricular filling pressures increase (due to volume overload or poor pumping), these pressures are transmitted backward, causing increased hydrostatic pressure in the pulmonary circulation, leading to pulmonary congestion.

Correct answer: A — Renin-Angiotensin-Aldosterone System (RAAS)

Heart failure triggers compensatory mechanisms, notably the activation of the RAAS, which promotes sodium and water retention to maintain blood volume, though this exacerbates fluid overload in HF.

Correct answer: A — Left ventricle

The left ventricle is the main pumping chamber responsible for ejecting oxygenated blood into the systemic circulation.

Correct answer: C — Decreased blood volume and tissue perfusion

Reduced cardiac output means the heart is pumping less blood per minute. This directly leads to decreased blood volume delivered to the tissues, resulting in decreased tissue perfusion and potentially systemic hypovolemia, which is a hallmark of heart failure.

Correct answer: C — The dependence of stroke volume on ventricular filling

The Frank-Starling mechanism states that the stroke volume of the heart increases in response to an increase in the volume of blood filling the ventricles (increased preload). Heart failure often involves a failure in this mechanism to compensate properly.

Correct answer: B — Diastole (Relaxation/Filling)

Diastole is the phase when the ventricles should relax and fill with blood. Diastolic dysfunction means this filling phase is impaired.