From the Guidelines
Carcinoid heart disease is primarily associated with carcinoid syndrome, which occurs when neuroendocrine tumors release excessive serotonin and other vasoactive substances into the bloodstream, leading to primary comorbidities of right-sided heart failure, tricuspid valve regurgitation, pulmonary valve stenosis, and right ventricular dysfunction, as well as secondary comorbidities including hepatic metastases, peripheral edema, ascites, fatigue, and decreased exercise tolerance due to right heart failure. The primary comorbidities of carcinoid heart disease include:
- Right-sided heart failure
- Tricuspid valve regurgitation
- Pulmonary valve stenosis
- Right ventricular dysfunction These occur because the vasoactive substances released by carcinoid tumors cause fibrotic changes in heart valves, predominantly affecting the right side of the heart since the lungs metabolize these substances before they reach the left heart 1. Secondary comorbidities include:
- Hepatic metastases (which allow vasoactive substances to bypass liver metabolism)
- Peripheral edema
- Ascites
- Fatigue
- Decreased exercise tolerance due to right heart failure Less commonly, patients may develop left-sided valve disease if they have a patent foramen ovale, bronchial carcinoid, or severe lung disease 1. Patients may also experience complications of the underlying carcinoid syndrome such as flushing, diarrhea, and bronchospasm 1. Cardiac arrhythmias, particularly atrial fibrillation, can develop as the heart chambers enlarge 1. Management requires a multidisciplinary approach addressing both the underlying neuroendocrine tumor and the cardiac manifestations, often including somatostatin analogs to control hormone secretion and cardiac surgery for severe valve disease 1.
From the Research
Primary Comorbidities of Carcinoid Heart Disease
- Right-sided valvular heart disease, involving most commonly the tricuspid and pulmonary valves 2, 3, 4
- Fibrous endocardial plaques in the heart 2, 4
- Tricuspid and pulmonic regurgitation and less frequently stenosis of these valves 3
- Right-sided heart failure secondary to diseased tricuspid and pulmonary valves 5, 3
Secondary Comorbidities of Carcinoid Heart Disease
- Congestive heart failure symptoms 2
- Diarrhea, which can be refractory to somatostatin analogs (SSAs) and may require treatment with telotristat 6
- Bronchoconstriction 2
- Flushing and telangiectasias 2
- Left-sided valvular involvement, which occurs rarely 2, 4
- Angina associated with coronary vasospasm, which occurs in ~10% of subjects with CHD 4