eComment. Cardiovascular surgery in carcinoid heart disease

Mabvuure and colleagues succinctly summarize the data regarding valve replacement surgery and specifically the choice of valve prosthesis in carcinoid heart disease [1]. They correctly note there is very little data which compares mechanical and biological valves in this patient population. They reported on studies which represent a total of 51 patients who underwent tricuspid valve replacement. The authors did not include an important retrospective study which investigated the management and outcome of valve replacement surgery in 26 patients with carcinoid heart disease operated on between 1985 and 1992 [2]. In this study, 20 out of the 26 tricuspid valve replacements were performed with mechanical valves. They reported a 35% perioperative mortality. Of the 17 patients who survived the initial operation there were 9 late deaths at a mean of 19 months postoperatively. No deaths were due to cardiovascular causes. The same group looked at temporal trends in perioperative mortality in patients with carcinoid heart disease undergoing valve replacement surgery (3). 30-day perioperative mortality fell from 25% for patients operated between 1981 and 1989 to 9% for patients operated between 1995 and 2000. Another group reported the outcome of 10 patients, who all underwent tricuspid valve replacement between 2001 and 2006 with bioprosthetic prostheses (4). Overall, perioperative mortality was 20%. At a mean follow-up of 37 months, there were no cases of structural valve deterioration. There are compelling reasons for the use of bioprosthetic prostheses in patients with neuroendocrine tumours. Mechanical valves require life- long anti-coagulation with warfarin. The majority of patients with carcinoid heart disease will have liver metastases. This maybe associated with impaired liver function which may make control of anticoagulation more difficult and thereby increase the risk of haemorrhage. Secondly, these patients may require resection of liver metastases to control symptoms of carcinoid syndrome if they are refractory to medical therapy which will require interruption of anti-coagulation therapy. In summary, studies undertaken in the past 2 decades [3,4,5] show reduced perioperatively risk compared to studies which report on patients operated on in the 1980s [2]. There are no reports of significant bioprosthetic valve degeneration in any of these modern series supporting their use in this patient group. Conflict of interest: none declared.