Multidisciplinary team management of carcinoid heart disease

Abstract

Carcinoid heart disease (CHD) is a consequence of valvular fibrosis triggered by vasoactive substances released from neuroendocrine tumours, classically in those with metastatic disease and resulting in tricuspid and pulmonary valve failure. CHD affects one in five patients who have carcinoid syndrome (CS). Valve leaflets become thickened, retracted and immobile, resulting most often in regurgitation that causes right ventricular dilatation and ultimately, right heart failure. The development of CHD heralds a significantly worse prognosis than those patients with CS who do not develop valvular disease. Diagnosis requires a low threshold of suspicion in all patients with CS, since symptoms occur late in the disease process and clinical signs are difficult to elicit. As a result, routine screening is recommended using the biomarker, N-terminal pro-natriuretic peptide, and regular echocardiography is then required for diagnosis and follow-up. There is no direct medical therapy for CHD, but the focus of non-surgical care is to control CS symptoms, reduce tumour load and decrease hormone levels. Valve surgery improves long-term outcome for those with severe disease compared to medical management, although peri-operative mortality remains at between 10 and 20% in experienced centres. Therefore, care needs to be multidisciplinary at all stages, with clear discussion with the patient and between teams to ensure optimum outcome for these often-complex patients.

Keywords: carcinoid heart disease; neuroendocrine tumours; somatostatin analogues; surgery; valvular heart disease.

Figure 1

Schematic diagram illustrating the valve layers.

Figure 2

Electrocardiogram of a 75-year-old male who was diagnosed with GI-NET 5 years after developing symptoms. He presented with active weight loss, severe diarrhoea and flushing. At the time of presentation, the patient had severe tricuspid regurgitation, severe pulmonary regurgitation, with right ventricular dilatation and impairment. His resting 12-lead ECG demonstrate sinus rhythm with normal axis but ECG criteria for incomplete right bundle branch block with an rSR complex in V1.

Figure 3

Chest radiograph of a 74-year-old male who was diagnosed with GI-NET in 2015 and found to have elevated NT proBNP, which was attributed to age and hypertension without evidence of CHD. He remained under follow-up, developing tricuspid regurgitation that became severe and was associated with breathlessness. He was found, however, to have a right pleural effusion that was exudative, without cellular infiltrate and with normal high-resolution computed tomogram and with normal thoracoscopy.

Figure 4

Apical four-chamber view from a transthoracic echocardiogram demonstrating the hallmark features of thickening, restriction of motion and retraction of the tricuspid valve leaflets, indicated by the arrow. The image has been frozen at end-systole, before the atrio-ventricular valve leaflets should be open but, in this case, the tricuspid valve leaflets are clearly open at a time when the mitral valve leaflets are closed. LA, left atrium; LV, left ventricle; RA, right atrium; RV, right ventricle.

Figure 5

Tilted parasternal long axis view from a transthoracic echocardiogram using colour Doppler to demonstrate severe, central tricuspid regurgitation into the right atrium due to carcinoid heart disease. RA, right atrium; RV, right ventricle.

Figure 6

Tilted parasternal long axis view from a transthoracic echocardiogram using 2D (left panel) and colour Doppler (right panel) in a side-by-side format to demonstrate flow acceleration (indicated by the arrow) through fixed, retracted pulmonary valve leaflets, with the branch pulmonary arteries at the bottom of the image. MPA, main pulmonary artery; RVOT, right ventricular outflow tract.

Figure 7

Mid-oesophageal long axis view of the pulmonary valve from a transoesophageal echocardiogram using colour Doppler to demonstrate severe pulmonary regurgitation (indicated by the arrow) that could not be identified in a 73-year-old ex-smoker with limited transthoracic acoustic window. AV, aortic valve; MPA, main pulmonary artery; RVOT, right ventricular outflow tract.

Figure 8

Agitated saline contrast transthoracic echocardiogram from the apical four-chamber view after release of Valsalva, with contrast seen in the left ventricle within three RR cycles from injection (the arrow indicates the ultrasound reflected from agitated saline giving the ‘white’ appearance within the ventricular cavity, compared to the black myocardium adjacent). This was a large patent foramen ovale in a 58-year-old female with symptomatic severe tricuspid regurgitation and right-to-left shunting at rest resulting in hypoxia that required device closure. LA, left atrium; LV, left ventricle.

Figure 9

A contiguous stack of short axis steady-state free precession cine images is acquired through the long axis of the left and right ventricles, with annotation to demonstrate endocardial delineation from which end-diastolic (and end-systolic volumes: not shown) volumes are created.