Transcatheter Aortic Valve Replacement

Case History: A 77-year-old man presents with fatigue and shortness of breath with minimal exertion. He is brought into the examination room in a wheelchair due to shortness of breath with ambulation. He has a history of hypertension, diabetes mellitus, and coronary artery disease with prior stent to left anterior descending artery. Examination is notable for a harsh III/VI late-peaking systolic murmur in the right upper sternal border that radiates to the carotid arteries. EKG shows left ventricular hypertrophy with strain. Laboratory results are notable for serum creatinine of 2.0 mg/dL. Echocardiography is notable for an ejection fraction of 35%, with global hypokinesis in a hypertrophied ventricle. The aortic valve is calcified and stenotic with a peak velocity of 4.2 m/s, a mean gradient of 45 mm Hg, and a calculated aortic valve area of 0.7 cm2. Computed tomography scan of the thorax reveals a densely calcified aorta (Figure 1).Figure 1. Computed tomography scan of thoracic aorta of patient with critical aortic stenosis. Left panel shows a transverse section and a densely and circumferentially calcified aorta (arrow). The right panel shows the calcified segment (arrow) in a 3D reconstructed view.Calcific aortic stenosis is a disease most commonly found in the elderly, with an estimated incidence of 2% to 4% in people >65 years of age,1 making it the most common acquired valvular disease seen in the developed world. Aortic stenosis may affect younger patients who have either congenitally bicuspid aortic valves or, less commonly in the developed world, a history of rheumatic fever as a child. The pathophysiology of calcific aortic stenosis is not completely understood, but the disease is thought to be secondary to leaflet stress and shares some features histopathologically with atherosclerosis; inflammatory-rich plaques develop on the leaflets and subsequently become mineralized.1 The …