The Role of Transthoracic Echocardiography for Assessment of Mortality in Patients with Carcinoid Heart Disease Undergoing Valve Replacement

SIMPLE SUMMARY: A proportion of patients with neuroendocrine tumours develop carcinoid syndrome and subsequent carcinoid heart disease (CHD). Valve replacement is indicated for patients with CHD when there is severe regurgitation and symptoms or evidence of right ventricular (RV) failure. The risk of 30-day mortality is high, yet the prognosis in those managed conservatively is poor. Consensus recommendations are that surgery is limited to those expected to live more than 12 months, but factors known to predict outcome are lacking. The aim of our retrospective study was to identify preoperative echocardiographic parameters that may be associated with prognosis. In our cohort of 49 patients with CHD undergoing valve surgery, we show a significant association between preoperative RV size and outcome, with one-year mortality rates of 57% vs. 33% for those with severe RV dilatation vs. normal RV size. This raises the question of whether surgery should be considered earlier, prior to RV dilatation. ABSTRACT: Patients with carcinoid heart disease (CHD) are referred for valve replacement if they have severe symptomatic disease or evidence of right ventricular (RV) failure and an anticipated survival of at least 12 months. Data are lacking, however, on the role of transthoracic echocardiography in predicting outcomes. We carried out a retrospective, single-centre cohort study of patients with a biopsy-confirmed neuroendocrine tumour (NET) and CHD undergoing valve replacement for severe valve disease and symptoms of right heart failure. The aim was to identify factors associated with postoperative mortality, both within one year of surgery and during long-term follow-up. Of 88 patients with NET, 49 were treated surgically (mean age: 64.4 ± 7.6 years; 55% male), of whom 48 had a bioprosthetic tricuspid valve replacement for severe tricuspid regurgitation; 39 patients had a pulmonary valve replacement. Over a median potential follow-up of 96 months (interquartile range: 56–125), there were 37 deaths, with 30-day and one-year mortality of 14% (n = 7) and 39% (n = 19), respectively. A significant relationship between RV size and one-year mortality was observed, with 57% of those with severe RV dilatation dying within a year of surgery, compared to 33% in those with normal RV size (p = 0.039). This difference remained significant in the time-to-event analysis of long-term survival (p = 0.008). RV size was found to reduce significantly with surgery (p < 0.001). Those with persisting RV dilatation (p = 0.007) or worse RV function (p = 0.001) on postoperative echocardiography had significantly shorter long-term survival. In this single-centre retrospective study of patients undergoing surgery for CHD, increasingly severe RV dilatation on preoperative echocardiography predicted adverse outcomes, yielding a doubling of the one-year mortality rate relative to normal RV size. These data support the possibility that early surgery might deliver greater long-term benefits in this patient cohort.