Review Question - QID 214756

This patient with chronic hypertension who is on lisinopril most likely has decreased end-diastolic volume, normal ejection fraction, and increased renin due to concentric hypertrophy of cardiac myocytes in response to the chronically increased blood pressure.

Chronic hypertension is defined as a sustained increase in systemic arterial pressure. Most cases of hypertension are idiopathic and are thought to be influenced by genetics, environmental factors such as salt intake, and vasoconstrictive influences. Over time, the cardiac muscle will accommodate to the increased pressure by engaging in concentric hypertrophy in order to generate increased force during systole. This change will result in decreased end-diastolic volume. The ejection fraction, which is the fraction of end-diastolic volume that is pumped forward during each contraction, would be preserved because there is no intrinsic deficit in myocardial function. Finally, renin levels will be increased because of decreased perfusion to kidney tubules.

Incorrect Answers:
Answer 1: Decreased end-diastolic volume, normal ejection fraction, and decreased renin activity would be seen in patients with failure of the renin-angiotensin-aldosterone cascade. Decreased renin production will result in decreased salt retention in the kidney tubules and subsequently decreased plasma volume. Cases of pathologic aldosterone secretion such as an aldosteronoma can cause hypertension and a low renin.

Answer 3: Decreased end-diastolic volume, increased ejection fraction, and increased renin activity would be seen in patients with acute hypovolemic shock. The sympathetic nervous system increases cardiac contractility, and the kidney increases renin release in response to hypoperfusion.

Answer 4: Increased end-diastolic volume, decreased ejection fraction, and increased renin activity would be seen in patients with heart failure. The primary abnormality in this state is decreased cardiac contractility, and the subsequent decrease in kidney perfusion results in increased renin activity and increased volume retention.

Answer 5: Increased end-diastolic volume, normal ejection fraction, and decreased renin activity occurs in response to acute increases in plasma volume such as substantially increased sodium intake. Increased perfusion to the kidney in this state results in inhibition of renin release.

Bullet Summary:
Patients with chronic hypertension will present with decreased end-diastolic volume, normal ejection fraction, and increased renin production.