A 55-year-old invasive/clinical cardiologist worked full time, exercised regularly, and was asymptomatic. Two weeks previously, he had new onset of angina on exertion. Echocardiography/Doppler and cardiac catheterization confirmed the clinical assessment of severe aortic stenosis with a valve area of 0.5 cm2/m2. The aortic valve was tricuspid; left ventricular ejection fraction was 0.60. Coronary arteriography showed no obstructive coronary artery disease. His body-mass index was 23 kg/m2, body surface area 1.7 m2, blood pressure 110/70 mm Hg, low-density lipoprotein 70 mg/dL, creatinine clearance 120 mL/min, and hemoglobin A1c 5.0. He had no comorbid conditions, and had never smoked. Several factors have to be taken into consideration in choosing a prosthetic heart valve (PHV; Table 1).1 The choice is between mechanical and biological valves. An important determining factor is weighing the risks of anticoagulant therapy with mechanical valves or structural valve deterioration (SVD) with biological valves. View this table: Table 1. Factors To Be Considered in the Decision for Choice of PHV In 1960, the first clinically implanted PHVs by Harken and by Starr were mechanical valves. The modified Starr-Edwards valve introduced in 1965 did not have SVD, with up to 40 years of follow-up.2 Other PHVs had similar results up to 20 to 30 years of follow-up.1 In patients with aortic stenosis,2 mechanical valves were proven to improve survival, functional class, and left ventricular function, and to reverse clinical heart failure; there were reductions of left ventricular mass and of pulmonary hypertension. All patients with mechanical valves need life-long anticoagulation with warfarin, which is well tolerated by many patients. ### Conclusion For patients <60 years of age requiring aortic valve replacement (AVR), a mechanical valve is recommended. Any mechanical valve that has been approved by the appropriate governing body (Food and Drug Administration in …