In patients with carcinoid syndrome undergoing valve replacement, will a biological valve have acceptable durability?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'In patients with carcinoid syndrome undergoing valve replacement, will a biological valve have acceptable durability?' Altogether, more than 130 papers were found using the reported search, of which 17 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. The pooled data from all papers represent 51 patients with carcinoid right heart disease who underwent tricuspid valve replacement. Two 'outcomes' studies reported a 30-day postoperative mortality of 16.7-18% and 2-year survival rates of 44 and 50%, respectively. Seventeen patients were detailed in case reports. Of these 17 patients, 7 died during the follow-up period. All but one of these patients had a normal bioprosthesis at echocardiography or at post-mortem. One patient with a plaque-covered valve had a functionally normal valve. We conclude that at present, the best available evidence suggests that although 30-day mortality approaches 20%, approximately half of patients with carcinoid syndrome undergoing tricuspid valve replacement can be expected to survive 2 years. Some patients survive considerably longer than this, beyond 10 years in some cases. Importantly, at autopsy, many replacement valves have been shown to be normal, with a few patients reported as having died of cardiac causes. This should be taken as cautious evidence that biological valves have an acceptable lifespan in patients with carcinoid syndrome and that the process of valve destruction seen in carcinoid patients does not continue to a significant level in the bioprosthesis. Caveats to this include the lack of any directly comparative trial and the predominance of case reports as opposed to higher-level evidence.