LearnWithTest

1 A 64-year-old man with long-standing hypertension presents with exertional dyspnea. Echocardiography shows concentric left ventricular hypertrophy. Which physiological principle best explains this adaptation?

Frank–Starling mechanism Laplace’s law and pressure overload hypertrophy Poiseuille’s law of resistance Fick’s principle of oxygen consumption

2 A patient with acute massive hemorrhage develops tachycardia and peripheral vasoconstriction. Which reflex is primarily responsible for these compensatory changes?

Cushing reflex Bezold–Jarisch reflex Baroreceptor reflex Pulmonary stretch reflex

3 A 58-year-old patient with heart failure has elevated left ventricular end-diastolic volume. Which physiological mechanism initially increases stroke volume despite reduced contractility?

Poiseuille’s law Frank–Starling mechanism Laplace’s law Bohr effect

4 A patient with chronic obstructive pulmonary disease develops secondary pulmonary hypertension. Which physiological mechanism causes the rise in pulmonary vascular resistance?

Hypoxic pulmonary vasoconstriction Parasympathetic activation Reduced sympathetic tone Decreased blood viscosity

5 A patient experiences syncope immediately after standing from a lying position. Which physiological failure most likely caused this episode?

Failure of baroreceptor-mediated vasoconstriction Excess vagal stimulation Increased venous return Enhanced myocardial contractility

6 A patient in septic shock presents with warm extremities and hypotension despite high cardiac output. Which mediator is primarily responsible for systemic vasodilation?

Angiotensin II Endothelin Nitric oxide Aldosterone

7 A patient with mitral stenosis develops progressive left atrial enlargement. Which hemodynamic change best explains this finding?

Increased left ventricular preload Elevated left atrial pressure due to outflow obstruction Decreased pulmonary venous pressure Reduced systemic vascular resistance

8 A patient with acute myocardial infarction develops cardiogenic shock. Which cardiovascular variable is most immediately reduced?

Stroke volume Blood viscosity Venous return Hematocrit

9 An endurance athlete has resting bradycardia with high stroke volume. Which physiological adaptation explains this?

Reduced cardiac compliance Increased parasympathetic (vagal) tone Decreased myocardial contractility Reduced baroreceptor sensitivity

10 A patient with severe chronic anemia develops high-output cardiac failure. Which physiological factor contributes most to increased cardiac output?

Increased blood viscosity Reduced systemic vascular resistance Increased afterload Reduced venous return

11 A patient with right heart failure presents with bilateral peripheral edema. Which Starling force is primarily responsible for fluid accumulation?

Increased capillary hydrostatic pressure Increased plasma oncotic pressure Decreased interstitial osmotic pressure Enhanced lymphatic drainage

12 Following myocardial infarction, a patient develops ventricular tachycardia due to re-entry. Which electrophysiological abnormality is required for re-entry to occur?

Shortened refractory period Unidirectional conduction block Enhanced parasympathetic tone Prolonged PR interval

13 A patient with aortic regurgitation has a widened pulse pressure. Which hemodynamic change explains this finding?

Decreased systolic pressure Increased systolic and decreased diastolic pressure Reduced stroke volume Decreased arterial compliance only

14 A patient with pulmonary embolism develops acute right ventricular failure. Which physiological mechanism explains the right ventricular strain?

Increased pulmonary vascular resistance Decreased systemic vascular resistance Reduced left ventricular preload Increased venous return

15 A patient with constrictive pericarditis develops reduced cardiac output. Which physiological parameter is most directly impaired?

Afterload Preload due to restricted ventricular filling Blood viscosity Heart rate regulation