What is the role of diuretics in Aortic Stenosis (AS)?

From the Guidelines

Diuretics should be used with extreme caution in patients with aortic stenosis (AS) and are generally not recommended due to the risk of hypotension and decreased cardiac output. The primary concern with diuretic use in AS is that these patients are preload-dependent, meaning they rely on adequate blood volume to maintain cardiac output across the stenotic valve 1. Excessive diuresis can lead to dangerous reductions in preload, resulting in hypotension, decreased cardiac output, and even syncope or cardiovascular collapse.

Key Considerations

• Loop diuretics like furosemide may be considered at low doses (starting at 20-40mg daily) only when there is clear evidence of volume overload or heart failure symptoms, but they should be initiated at the lowest effective dose with careful monitoring 1.
• Thiazide diuretics should typically be avoided due to their potential to cause hypokalemia and worsen cardiac function.
• If diuretics are deemed necessary, close monitoring of blood pressure, electrolytes (particularly potassium), and renal function is essential, with follow-up within 1-2 weeks of initiation or dose adjustment.

Alternative Treatment Options

• For patients with AS who have hypertension, other agents like ACE inhibitors at low doses may be preferable to diuretics when blood pressure control is needed 1.
• Calcium channel blockers (CCBs) and alpha-blockers should be avoided where possible in patients with AS and hypertension due to their potential to increase mortality and cardiovascular events 1.
• Mineralocorticoid receptor antagonists (MRAs) may be well tolerated in patients with AS, but their role in delaying the onset of left ventricular systolic dysfunction (LVSD) or reducing left ventricular mass is unclear 1.

From the Research

Diuretics in Aortic Stenosis (AS)

• The use of diuretics in patients with aortic stenosis is not explicitly discussed in the provided studies as a primary treatment option 2, 3, 4, 5, 6.
• However, the study by 6 mentions diuretics as one of the antihypertensive therapy options used in patients with moderate to severe aortic stenosis.
• The primary focus of the studies is on the use of other antihypertensive medications such as renin-angiotensin system (RAS) inhibitors, beta-blockers, and vasodilators in the management of AS 2, 4, 6.
• RAS inhibitors have been shown to be potentially beneficial in retarding the progression of valvular stenosis and left ventricle remodeling 2, 4.
• Beta-blockers have also been studied, and recent research suggests they may be safe and beneficial in patients with AS, although their use was previously considered a relative contraindication 2.

Clinical Implications

• The clinical implications of diastolic dysfunction in aortic stenosis are discussed in the study by 3, which highlights the importance of left ventricular remodeling and myocardial fibrosis in the progression of the disease.
• The study by 5 provides an overview of pharmacological treatment options for heart failure with reduced ejection fraction, which may be relevant to patients with AS who develop heart failure.
• The use of diuretics in these patients may be considered as part of the overall management strategy, although the provided studies do not specifically address their role in AS 6.