Results of Contemporary Valve Surgery in Patients with Carcinoid Heart Disease

BACKGROUND: Carcinoid tumor is a slow-growing type of neuroendocrine tumor, originating from enterochromaffin cells and secreting mainly serotonin. The diagnosis is based on clinical symptoms, hormone blood levels, radiological and nuclear imaging, and histological confirmation. However, most patients have metastases at the time of diagnosis because the clinical signs often remain unnoticed or are attributed to other abdominal conditions. In up to 50% of patients the endocardium is affected due to a hormonally active tumor profile. The study aim was to report the outcome of surgical treatment in patients with carcinoid heart disease, including the data of radiological and nuclear imaging, histological diagnosis, and follow up information.

METHODS: Between 2008 and 2014, a total of 39 consecutive patients (28 males, 11 females; mean age 66 years; range: 28-84 years) with carcinoid heart syndrome were operated on at the authors' institution. Valvular heart disease was diagnosed with two-dimensional echocardiography. The study population included 26 patients (67%) with severe metastatic disease, who underwent radiotherapy preoperatively, and 13 patients (33%) who were metastasis-free and did not receive preoperative systemic therapy. Follow up was available for all hospital survivors, all of whom underwent serial echocardiographic follow up postoperatively. Adverse cardiac events were defined as cardiac-related death, a need for valvular reintervention, the occurrence of valve prosthesis-related complications, or echocardiographic evidence of new, high-degree valvular dysfunction during follow up.

RESULTS: The majority of patients (n = 34; 87%) underwent isolated tricuspid valve replacement, while simultaneous pulmonary valve replacement was performed in five patients (13%). Postoperative complications included reoperation for bleeding in five patients (13%) and new heart block requiring pacemaker implantation in 10 (25%). The in-hospital mortality was 5% (n = 2). The overall survival was 43% at six years postoperatively. At the latest follow up, 12 of the 17 survivors were in NYHA class I, and five in NYHA class II. The adverse cardiac event rate was 71%. Echocardiographically, 46% of patients (6/13) showed at least stationary or mild improvement in the right ventricular ejection fraction at follow up, with no evidence of paravalvular leak, infective endocarditis, or progressive other native valvular carcinoid affection. Postoperatively, the right atrial dimensions were preserved as normal in 23 patients (59%), mildly dilated in six (15%), moderately dilated in three (8%), and severely dilated in seven (18%). Valve-in-valve transcatheter aortic valve implantation was performed in two patients (12%) due to structural degeneration of the valve bioprosthesis and native valve disease progression.

CONCLUSIONS: Despite advanced systemic disease, the surgical treatment of patients with carcinoid heart syndrome is associated with an acceptable perioperative risk and satisfactory mid-term survival. Those patients who survived valve surgery benefited from a significant improvement in their functional capacity. Percutaneous procedures may represent a useful tool to reduce the risk of late valvular reinterventions.