Heart Failure USMLE Step 1 Practice Question
A 68-year-old man with prior anterior myocardial infarction presents with exertional dyspnea, orthopnea, and bilateral ankle edema. Vital signs show BP 128/82 mmHg, HR 94 bpm, RR 18/min, and SpO2 98% on room air. Echocardiography reveals diffuse hypokinesis with ejection fraction of 28%. BNP is elevated at 450 pg/mL. He denies chest pain. Currently on aspirin but not on ACE inhibitors. Which neurohormonal change most likely contributes to disease progression?
Answer choices
- AActivation of the renin angiotensin aldosterone systemCorrect answer
- BSuppression of sympathetic tone
- CDecreased renin secretion
- DIncreased atrial natriuretic peptide causing ventricular fibrosis
- EReduced norepinephrine release
- FDecreased vasopressin secretion leading to polyuria and worsening volume depletion
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