The development of carcinoid heart disease (CaHD) is still relatively unknown at present. It is difficult to define an optimal follow-up for patients initially free from cardiac involvement. The aim of this study was to assess the prevalence and the evolution of CaHD using annual echocardiographic follow-up.

We reviewed from our database 137 patients (61±12 years, 53% men) with histologically proven neuroendocrine tumor between 1997 and 2017. All patients underwent serial conventional transthoracic echocardiographic studies. Right-sided and left-sided CaHD were systematically assessed. We used a previous validated echocardiographic scoring system of severity for the assessment of CHD. An increase of 25% of the score was considered as significant.

Mean follow-up was 2.6±3.5 years [0;16]. Prevalence of CaHD was 27% (37 pts) at baseline and 36% (49 pts) at the end of follow-up. Among patients with initial CaHD followed for more than one year, disease progression was observed in 28% of cases. Among the patients free from initial cardiac involvement, an onset of the disease was observed during follow-up in 21% of cases. The onset of CHD could be very late, more than 5 years from the initial echocardiographic examination in 42% of our cases (Figure 1). This late occurrence of CaHD was only observed in patients presenting with new resumption of neuroendocrine tumor (symptoms, increased of 5-HIAA, occurrence of new metastasis).

Our study demonstrated that in patients without initial CaHD, cardiac involvement may occur tardily after a normal initial assessment. Our data suggest the need for prolonged echocardiographic follow-up in patients presenting with a resumption of tumor process (Figure 1).