Medications to Avoid in Aortic Stenosis
Beta-blockers should be avoided in patients with aortic stenosis who have concurrent moderate or greater aortic regurgitation, and diuretics should be used sparingly in those with small left ventricular chambers and concentric hypertrophy. 1
Beta-Blockers: Specific Contraindications
Beta-blockers are absolutely contraindicated in chronic aortic regurgitation because slowing the heart rate prolongs diastolic filling time, allowing more regurgitant flow and worsening volume overload. 1
In patients with both severe aortic stenosis AND moderate or greater aortic regurgitation, beta-blockers should be avoided unless a compelling indication exists such as heart failure with reduced ejection fraction, recent myocardial infarction, or life-threatening arrhythmias. 1
When beta-blockers are indicated for compelling reasons (HFrEF, post-MI, arrhythmias, angina), they should be started at low doses and titrated cautiously while monitoring for signs of reduced cardiac output. 1
Diuretics: Use With Extreme Caution
Diuretics should be used sparingly in patients with small left ventricular chambers and concentric hypertrophy, which is common in aortic stenosis. 1, 2
Excessive preload reduction from aggressive diuresis can critically impair forward flow across the stenotic valve, causing worsening hypotension and compromised cardiac output. 2
Diuretics should only be used to achieve and maintain euvolemia—once euvolemic, the dose should be reduced to the minimum necessary or discontinued entirely. 2
Vasopressors: Phenylephrine Concerns
Phenylephrine (a pure α₁-adrenergic agonist) substantially increases systemic vascular resistance, which when combined with the fixed obstruction of a stenotic aortic valve creates a "two resistors in series" situation that can markedly reduce cardiac output. 1
This hemodynamic effect makes phenylephrine particularly problematic in the perioperative or acute care setting for patients with aortic stenosis. 1
Preferred Antihypertensive Agents (What NOT to Avoid)
Renin-angiotensin system (RAS) inhibitors (ACE inhibitors or ARBs) are recommended as first-line therapy for hypertension in severe aortic stenosis and should NOT be avoided. 1, 2, 3
RAS inhibitors provide benefits beyond blood pressure control, including reduction of left ventricular fibrosis, better symptom relief, and improved exercise tolerance. 1, 3
Start antihypertensive therapy at low doses and titrate slowly upward to minimize hemodynamic instability. 1, 3
Critical Pitfalls to Avoid
Do not withhold all antihypertensive therapy based on outdated concerns—hypertension in aortic stenosis creates "two resistors in series" and markedly increases cardiovascular mortality risk. 3
Avoid excessive blood pressure lowering that could compromise coronary perfusion, especially in patients with left ventricular hypertrophy. 3
Mandatory cardiology consultation is advised for any patient with moderate-to-severe aortic stenosis who requires antihypertensive therapy adjustments. 1, 2