Cardiovascular · Year 1 · from Cardiovascular

Case 1: Severe Aortic Stenosis - Classic Presentation

Patient Presentation

Demographics: 78-year-old male

Chief Complaint: Exertional chest pain and dyspnea for 3 months

History of Present Illness: A 78-year-old male with history of hypertension and hyperlipidemia presents with progressive exertional symptoms over the past 3 months. He reports substernal chest pressure when walking up hills or climbing stairs, relieved by rest within 5 minutes. He also experiences dyspnea with exertion and has had two episodes of lightheadedness (near-syncope) after climbing a flight of stairs. He denies symptoms at rest. His primary care physician heard a heart murmur and referred him for evaluation.

Physical Examination:

• Vital Signs: BP 124/82 mmHg, HR 72 bpm, RR 16/min, SpO2 97% on room air
• General: Elderly male, no acute distress at rest
• Cardiovascular:
• Murmur: 4/6 harsh, crescendo-decrescendo systolic ejection murmur at right upper sternal border
• Radiation: Murmur radiates to carotid arteries bilaterally
• Carotid pulse: Parvus et tardus (weak and delayed upstroke)
• S2: Soft (diminished A2 component)
• S4: Present (atrial gallop)
• PMI sustained, not displaced
• Lungs: Clear
• Extremities: No edema

Workup

• ECG: Sinus rhythm, LVH by voltage criteria, secondary repolarization abnormalities
• Chest X-ray: Normal heart size, calcified aortic valve visible on lateral view
• Echocardiogram:
• Aortic valve: Heavily calcified, restricted leaflet motion
• Aortic valve area: 0.7 cm2 (severe <1.0 cm2)
• Mean gradient: 52 mmHg (severe >40 mmHg)
• Peak velocity: 4.8 m/s (severe >4.0 m/s)
• LV ejection fraction: 55%
• Concentric LVH: Wall thickness 1.5 cm
• Coronary Angiography: Moderate non-obstructive CAD

Diagnosis

Severe symptomatic degenerative aortic stenosis with classic symptom triad

Valvular Heart Disease Correlation:

Pathophysiology of Aortic Stenosis:

1. Etiology - Degenerative Calcification:

• Most common cause in elderly patients (>65 years)
• Calcification of tricuspid aortic valve
• Similar risk factors to atherosclerosis
• Progressive narrowing over decades

1. Pressure Overload on Left Ventricle:

• LV must generate higher pressure to eject through narrowed orifice
• Response: Concentric hypertrophy (sarcomeres in parallel)
• Wall thickness increases to normalize wall stress
• LaPlace: Wall stress = (Pressure x radius) / (2 x wall thickness)

1. Consequences of Concentric LVH:

• Increased myocardial oxygen demand
• Decreased compliance (diastolic dysfunction)
• Subendocardial ischemia (compression of intramyocardial vessels)
• S4 gallop from forceful atrial contraction

Classic Symptom Triad and Mechanisms:

Physical Examination Findings Explained:

• Crescendo-decrescendo murmur: Turbulent flow through stenotic valve
• Late-peaking murmur: In severe AS, peak is delayed as ejection time prolongs
• Radiation to carotids: High-velocity jet directed toward ascending aorta
• Parvus et tardus: Slow rise and low amplitude of arterial pulse reflects fixed obstruction
• Soft S2: Calcified valve closes poorly, diminished A2
• S4 gallop: Stiff LV requires forceful atrial contraction

Severity Assessment:

Treatment

Indication for Intervention:

• Severe AS + Symptoms = Class I indication for valve replacement
• Asymptomatic severe AS with EF <50% = Also Class I indication

Options:

1. Surgical Aortic Valve Replacement (SAVR):

• Traditional approach
• Excellent durability
• Requires sternotomy and cardiopulmonary bypass

1. Transcatheter Aortic Valve Replacement (TAVR):

• Catheter-based approach (femoral or alternative access)
• Now approved for all surgical risk categories
• Preferred for high/prohibitive surgical risk
• Comparable outcomes to SAVR in intermediate risk

Choice for This Patient:

• Age 78, moderate non-obstructive CAD, good LV function
• Heart team discussion
• TAVR likely appropriate given age and comorbidities
• SAVR remains option if complex anatomy

Medical Management (Supportive only):

• No medical therapy alters AS progression
• Maintain euvolemia
• Avoid hypotension (fixed obstruction)
• Treat atrial fibrillation aggressively if develops

Clinical Image

Image Description: Gross pathological specimen of a severely stenotic aortic valve with rheumatic changes. The valve leaflets show marked thickening, calcification, and commissural fusion resulting in a significantly narrowed orifice. This illustrates the structural abnormality that creates obstruction to left ventricular outflow.

Source: Wikimedia Commons - Aortic stenosis, rheumatic License: Public Domain (CDC/Dr. Edwin P. Ewing, Jr.) URL: https://commons.wikimedia.org/wiki/File:Aortic_stenosis_rheumatic,_gross_pathology_20G0014_lores.jpg

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