From the Guidelines
Severe aortic stenosis (AS) is characterized by symptoms such as exertional dyspnea, decreased exercise tolerance, heart failure symptoms, exertional angina, exertional syncope, or presyncope, and is usually defined by valve hemodynamics including AV Vmax ≥4 m/s, mean DP ≥40 mm Hg, or AVA typically ≤1.0 cm². These symptoms and signs are critical to recognize as they indicate significant narrowing of the aortic valve, which can lead to increased morbidity, mortality, and decreased quality of life if left untreated 1. The classic triad of symptoms includes angina, syncope, and heart failure symptoms, and physical examination may reveal a harsh, late-peaking systolic murmur, a diminished or absent aortic component of the second heart sound, and a slow-rising, diminished carotid pulse 1. Some key points to consider in the diagnosis of severe AS include:
- The use of echocardiography as the key diagnostic tool to confirm the presence of AS, assess the degree of valve calcification, and evaluate LV function and wall thickness 1
- The importance of measuring valve area and mean pressure gradient to quantify AS severity, with severe AS typically defined by a valve area ≤1.0 cm² and mean pressure gradient ≥40 mm Hg 1
- The recognition of low-flow, low-gradient severe AS with preserved LVEF, which should be considered in patients with a severely calcified aortic valve, an aortic velocity <4.0 m/s, and a valve area ≤1.0 cm² when stroke volume index is <35 mL/m² 1
- The role of dobutamine stress testing in distinguishing truly severe AS from pseudo-severe AS, particularly in patients with low-flow, low-gradient AS 1. Overall, prompt recognition and treatment of severe AS are crucial to improve outcomes and reduce morbidity and mortality, with aortic valve replacement (AVR) being the primary treatment option for symptomatic patients with severe AS 1.
From the Research
Signs of Severe Aortic Stenosis (AS)
- Shortness of breath, experienced by 91.0% of patients 2
- Dizziness, reported by 30.2% of patients 2
- Chest pain, affecting 28.9% of patients 2
- Left ventricular hypertrophy, present in 62.1% of patients 2
- Ejection fraction (EF) <50%, found in 27.3% of patients 2
- Advanced disease stage, characterized by high aortic valve velocities, with some patients having peak aortic jet velocity (Vmax) values ≥6 m/s 3
- New York Heart Association classification-III/IV and severe left ventricular hypertrophy, more frequent in patients with extremely severe AS (Vmax ≥6 m/s) 3
Disease Severity and Treatment
- Severe AS is often characterized by an aortic valve area (AVA) <1 cm2, indexed AVA <0.6 cm2/m2, maximum jet-velocity (Vmax) >4 m/s, and/or mean transvalvular gradient >40 mm Hg 2
- Transcatheter aortic valve replacement (TAVR) is a treatment option for patients with severe AS, including those with heart failure 4
- TAVR has been shown to be effective in patients with severe AS, including those with extremely severe AS (Vmax ≥6 m/s), although these patients may have higher paravalvular leak (PVL) rates 3
- Management of severe AS remains suboptimal in a significant proportion of patients, with only 76.2% of patients receiving a decision for intervention (transcatheter or surgical aortic valve replacement) 2