Mixed Aortic Valve Disease

KEY FEATURES

ESSENTIALS OF DIAGNOSIS

• Moderate aortic regurgitation and stenosis (estimated aortic valve area 0.8–1.2 cm²)

GENERAL CONSIDERATIONS

• In mixed aortic stenosis and regurgitation, 1 of the 2 lesions usually predominates and management is predicated on the dominant lesion

• When both lesions are moderate, the degree of hemodynamic disturbance is considerably more than one would expect from either lesion alone

• Moderate aortic regurgitation challenges the concentrically hypertrophied left ventricle from aortic stenosis by doing the following:

  • – Adding diastolic volume, which moves the ventricle up its steep pressure–volume curve

  • – Causing considerable diastolic pressure that is transmitted to the lungs, resulting in dyspnea and pulmonary congestion

CLINICAL PRESENTATION

SYMPTOMS AND SIGNS

• Dyspnea

• Heart failure symptoms

• Effort syncope

• Angina pectoris

PHYSICAL EXAM FINDINGS

• Enlarged left ventricular impulse

• S₃ or S₄

• Ejection sound if bicuspid valve

• Diminished aortic S₂

• Typical harsh systolic ejection murmur and high-pitched diastolic decrescendo murmur in the aortic area

• Signs of heart failure may be present

• Peripheral signs of aortic regurgitation are usually absent because of the reduction in stroke volume from significant aortic stenosis

DIFFERENTIAL DIAGNOSIS

• Severe aortic regurgitation with mild aortic stenosis

• Severe aortic stenosis and mild regurgitation

• The murmur of patent ductus arteriosus may be mimicked by moderate aortic stenosis/aortic regurgitation

DIAGNOSTIC EVALUATION

LABORATORY TESTS

• Brain natriuretic peptide test: elevated in heart failure

ELECTROCARDIOGRAPHY

• ECG findings:

  • – Left ventricular hypertrophy

  • – Left atrial enlargement

IMAGING STUDIES

• Chest x-ray findings:

  • – Enlarged left heart chambers

  • – Aortic valve calcification

  • – Pulmonary congestion

• Echocardiography:

  • – Left ventricular hypertrophy and systolic function

  • – Left atrial enlargement

  • – Thickened aortic valve

  • – Dilated aorta

• Doppler echocardiography:

  • – Continuous-wave Doppler measures the pressure gradient across the valve

  • – The continuity equation accurately determines valve area

  • – Color-flow Doppler assesses the severity of aortic regurgitation

DIAGNOSTIC PROCEDURES

• Transesophageal echocardiography can image the aortic valve orifice area in difficult cases

• Cardiac catheterization and angiography are frequently valuable:

  • – To confirm the severity of aortic stenosis and regurgitation

  • – To assess left ventricular diastolic performance

TREATMENT

CARDIOLOGY REFERRAL

• Symptoms

• Suspected moderately severe disease

HOSPITALIZATION CRITERIA

• Evidence of heart failure

• Suspicion of endocarditis

• Significant arrhythmias

MEDICATIONS

• Use diuretics for heart failure

• Vasodilator drugs are relatively contraindicated because of the aortic stenosis

THERAPEUTIC PROCEDURES

• Transcatheter aortic ...