Abstract 18729: Prosthetic Valve Positioning - Not a Static Question
A 65-year-old female with a history of bicuspid aortic valve s/p AVR with a Medtronic Hall mechanical valve presented with chest pain. Her recent history was notable for one week of intermittent substernal chest pain present when lying in the left lateral position. Initial ECG, obtained during an episode of chest pain, revealed 2 mm ST segment depression in the anterolateral leads and ST segment elevation in lead aVR. The ECG changes normalized with cessation of her chest pain. Laboratory evaluation showed an INR of 3.5 (on warfarin), and normal cardiac biomarkers. Chest imaging, including CT angiography, was unremarkable. Physical examination demonstrated a normal jugular venous pressure, a mechanical second heart sound, and a II/VI crescendo-decrescendo systolic murmur at the right upper sternal border. Transthoracic echocardiography (TTE) revealed normal biventricular systolic function and a mechanical valve in the aortic position, associated with mild aortic regurgitation.
Valve fluoroscopy revealed an aortic monoleaflet mechanical prosthesis with normal opening and closing angles in the supine position, but with closing restriction when in the left lateral decubitus position (closing angle 46 degrees, associated with recurrent chest pain and ischemic ECG changes). Transesophageal echocardiography (TEE) showed moderate aortic stenosis, mild aortic regurgitation, and multiple linear echodensities on the aortic prosthesis. These echogenicities were felt to represent thrombi, and the patient was treated with 5 doses of tPA and intravenous heparin. Subsequent TEE and valve fluoroscopy revealed improved prosthetic leaflet motion in supine and lateral decubitus positions.
This case describes an unusual presentation of mechanical aortic valve thrombosis. The contiguous association of the mechanical valve with the coronary ostia can contribute to ischemic complications, in this case positionally induced. It also highlights the value of timely valve fluoroscopy and the consideration of patient maneuvers to delineate valve function. Current guidelines support the use of thrombolytic therapy for small, left-sided thrombi, with recent literature suggesting that slowly infused low-dose tPA provides the optimal risk-benefit profile.
Author Disclosures: H.M. Hall: None.
- © 2015 by American Heart Association, Inc.