Management of Severe Aortic Stenosis

Initial Assessment and Risk Stratification

The American College of Cardiology recommends confirming severe aortic stenosis using echocardiographic criteria: aortic valve area ≤1.0 cm², peak velocity ≥4 m/sec, or mean gradient ≥40 mmHg 1, 3
Determine symptom status by taking a thorough history focused on exertional dyspnea, angina, syncope, or dizziness, and exercise capacity limitations below age and sex-specific predicted metabolic equivalents 1
Calculate surgical risk using the STS-PROM score and Heart Team assessment, with low risk defined as STS-PROM <3% with no additional risk factors, intermediate risk as STS-PROM 4-8%, and high risk as STS-PROM >8% 1, 2

For symptomatic severe AS, proceed with valve replacement, with SAVR preferred for low surgical risk (STS <3%) and TAVR a reasonable alternative in selected patients 1, 2
For intermediate surgical risk (STS 4-8%), either TAVR or SAVR is appropriate, with the Heart Team considering patient anatomy, frailty, and patient preference 1, 2
For high surgical risk (STS >8%), TAVR is a reasonable alternative to SAVR, and for prohibitive surgical risk, TAVR is the recommended approach 2

Most asymptomatic patients with normal left ventricular function should undergo watchful waiting with regular clinical and echocardiographic follow-up every 6-12 months 3
Proceed with valve replacement in asymptomatic patients if left ventricular ejection fraction <50%, very severe AS with peak velocity ≥5 m/sec or mean gradient ≥60 mmHg, abnormal exercise stress test, rapid progression of stenosis, or undergoing cardiac surgery for another indication 1, 2, 3, 4

For low-flow, low-gradient AS, perform dobutamine stress echocardiography to distinguish true-severe from pseudo-severe AS, and proceed with AVR if flow reserve is present and truly severe AS is confirmed 1, 3, 4
For patients requiring non-cardiac surgery, asymptomatic patients can undergo elective non-cardiac surgery safely, though with increased risk of heart failure, and consider AVR before non-cardiac surgery if the procedure involves large volume shifts or if symptomatic 4

While awaiting valve replacement or in patients not candidates for intervention, maintain adequate preload, control heart rate, avoid vasodilators and positive inotropes, control blood pressure and other cardiovascular risk factors, and do not use statins to prevent progression of AS 2, 3

All complex decisions should involve a multidisciplinary Heart Team comprising cardiac surgery, interventional cardiology, cardiac imaging, anesthesiology, and geriatrics expertise, particularly for asymptomatic patients being considered for intervention, complex transcatheter or surgical procedures, and patients with challenging anatomy 1, 2

TAVR demonstrates sustained mortality benefit at 2 years compared to medical therapy in inoperable patients, with improved functional status and reduced rehospitalization, though with key complications including stroke, paravalvular aortic regurgitation, permanent pacemaker requirement, vascular access complications, and acute kidney injury 2