Cardiology · Valvular Heart Disease
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The classic clinical triad of Aortic Stenosis consists of exertional syncope, angina, and dyspnea (SAD).
Physical examination reveals a systolic crescendo-decrescendo murmur heard best at the right upper sternal border that radiates to the carotids.
The pulse character in severe Aortic Stenosis is described as pulsus parvus et tardus, meaning a weak and delayed carotid upstroke.
The murmur intensity of Aortic Stenosis decreases with Valsalva maneuver and handgrip exercise.
Echocardiography is the gold standard diagnostic test to confirm the diagnosis and assess the aortic valve area and mean pressure gradient.
Surgical Aortic Valve Replacement (SAVR) or Transcatheter Aortic Valve Replacement (TAVR) is the definitive treatment for symptomatic severe aortic stenosis.
Bicuspid aortic valve is the most common cause of Aortic Stenosis in patients younger than 70 years of age.
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A 72-year-old male presents to the clinic complaining of lightheadedness and chest tightness during his daily morning walks. On physical exam, he has a harsh systolic crescendo-decrescendo murmur heard at the right second intercostal space that radiates to the neck. Carotid palpation reveals a weak and delayed upstroke. He has no history of rheumatic fever, but his father had a heart valve replacement at age 55.
What is the most appropriate next step in the management of this patient?
Transthoracic echocardiogram
The patient presents with two of the three classic symptoms of aortic stenosis — exertional presyncope and angina — together with a murmur and carotid pulse contour typical of severe disease. An echocardiogram is required to confirm the diagnosis and quantify the severity of the stenosis.
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Etiology / Epidemiology
Most common in elderly due to calcific degeneration; younger patients often have a congenital bicuspid valve.
Clinical Manifestations
Classic triad: Angina, Syncope, Dyspnea (SAD). Murmur is a harsh systolic crescendo-decrescendo at the right upper sternal border.
Diagnosis
Transthoracic echocardiogram is the gold standard. Peak velocity ≥4.0 m/s or mean transvalvular gradient ≥40 mmHg defines severe (stage D1) disease, usually with a valve area ≤1.0 cm².
Treatment
SAVR or TAVR (selection by age, life expectancy, and surgical risk) is the definitive treatment. Use vasodilators cautiously in severe symptomatic cases; treat coexisting hypertension with low-dose therapy titrated gradually rather than withholding it.
Prognosis
Once symptoms develop, survival is poor without intervention. Untreated survival after symptom onset averages roughly 5 years with angina, 3 years with syncope, and 2 years with heart failure.
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Epidemiology & Etiology
In patients >70, calcific degeneration is the primary cause. In patients <70, a congenital bicuspid valve is the most frequent etiology. Rheumatic heart disease remains a significant cause in developing nations.
Pertinent Anatomy
The aortic valve typically has three leaflets. Stenosis creates a fixed left ventricular outflow tract (LVOT) obstruction, forcing the heart to generate high pressures to maintain cardiac output.
Pathophysiology
Chronic pressure overload leads to concentric left ventricular hypertrophy (LVH) to maintain wall stress. Eventually, the ventricle fails, leading to diastolic dysfunction and reduced coronary perfusion. This creates a fixed cardiac output state, limiting the ability to increase flow during exertion.
Clinical Manifestations
Patients present with the SAD triad: Syncope, Angina, and Dyspnea. Physical exam reveals a harsh systolic crescendo-decrescendo murmur radiating to the carotids and a pulsus parvus et tardus (weak and delayed carotid upstroke). Sudden cardiac death is a major risk in symptomatic patients.
Diagnosis
Transthoracic echocardiogram is the diagnostic test of choice. Severe stenosis is defined by a a peak aortic velocity ≥4.0 m/s or a mean gradient ≥40 mmHg, typically accompanied by an aortic valve area ≤1.0 cm². Exercise stress testing is contraindicated in symptomatic patients.
Treatment
Surgical aortic valve replacement (SAVR) or Transcatheter aortic valve replacement (TAVR) are the only definitive treatments. Medical management is palliative; use vasodilators cautiously in severe cases because abrupt preload or afterload reduction is poorly tolerated; coexisting hypertension should still be treated with standard antihypertensive therapy started at a low dose and titrated gradually. Patients must be monitored with serial echos.
Prognosis
Prognosis is dismal once symptoms appear; average survival is 2-3 years for heart failure, 3 years for syncope, and 5 years for angina. Surveillance echocardiography is severity-stratified: roughly every 3–5 years for mild aortic stenosis, every 1–2 years for moderate disease, and every 6–12 months once the stenosis is severe but the patient remains asymptomatic.
Differential Diagnosis
Hypertrophic Cardiomyopathy: Murmur intensity increases with Valsalva
Mitral Regurgitation: Holosystolic murmur at the apex
Aortic Sclerosis: No LVOT obstruction or symptoms
Pulmonic Stenosis: Murmur heard best at the left upper sternal border
Mitral Valve Prolapse: Mid-systolic click