Acute coronary syndromes in patients with prosthetic heart valves - A case-series

Background: There are few reports regarding acute coronary syndromes (ACS) in patients with prosthetic heart valves (PHV), mostly attributing the ACS to a PHV-derived coronary embolus. Objective: To characterize a case-series of ACS patients with PHV. Methods: All patients in our institution with previous PHV surgery and ACS during 1996-2005 were retrospectively analysed. Results: We identified 40 patients from the 15,878 patient database, whose mean age was 72.5±12.5 years and of whom 21 were male. The majority (n=28) had mechanical valves; 24 patients (60%) had an aortic prosthetic valve, 9 patients (22.5%) had a mitral valve prosthesis and 7 patients (17.5%) had both. The majority of patients had ≥2 risk factors for atherosclerotic disease. The median time from the PHV implantation to the subsequent ACS was 8.0 (4.7-12.1) years. Most patients had non-ST-segment elevation ACS rather than ST-segment elevation ACS (32 patients versus 8 patients). 12 patients (30%) had moderate to severe left ventricular dysfunction and 2 of them presented with cardiogenic shock. Atrial fibrillation on hospital admission was noted in 13 patients (32.5%). ACS management included coronary angiography in 32 patients (80%) which revealed coronary disease in 93%. Only 2 patients had normal coronary arteries and PHV-derived coronary emboli. The most frequent in-hospital complication was heart failure (n=11, 27.5%). Conclusions: Patients with PHV and ACS are a rare subgroup, more likely to be elderly with risk factors for atherosclerotic disease and to present with non-ST-segment-elevation ACS. The pathogenesis for ACS is commonly coronary atherosclerotic disease rather than PHV-derived emboli.