From the Guidelines
Carcinoid heart disease most commonly affects patients with advanced carcinoid syndrome, particularly those with metastatic neuroendocrine tumors originating from the small intestine (midgut). These patients are typically middle-aged to older adults, with the average age at diagnosis being 55-65 years 1. There is a slight male predominance in most studies. The key factor determining which carcinoid tumor patients develop heart disease is the presence of liver metastases, which allows vasoactive substances like serotonin to bypass hepatic metabolism and enter the systemic circulation. Approximately 50-60% of patients with carcinoid syndrome will develop some degree of cardiac involvement, with right-sided heart valve lesions being most common 1. The duration of carcinoid syndrome and elevated levels of 5-HIAA (a serotonin metabolite) in the urine correlate with the likelihood of developing cardiac manifestations. Patients with prolonged exposure to high levels of circulating serotonin and other vasoactive substances are at greatest risk for developing the characteristic fibrous endocardial plaques that lead to valve dysfunction.
Some key factors that increase the risk of developing carcinoid heart disease include:
- Elevated 5-HIAA levels (≥ 300 mcmol or 57 mg over 24 hours) 1
- Frequent flushing episodes (≥ 3 per day) 1
- Presence of liver metastases 1
- Advanced age (55-65 years) 1
It is essential to consider a cardiology consultation and echocardiogram to assess for carcinoid heart disease in patients with carcinoid syndrome and signs or symptoms of heart disease or planned major surgery 1.
From the Research
Patient Demographic Affected by Carcinoid Heart Disease
- The patient demographic most often affected by carcinoid heart disease is not explicitly stated in terms of specific age or gender in the provided studies 2, 3, 4, 5, 6.
- However, study 5 mentions that symptomatic carcinoid heart disease usually presents between 50 and 70 years of age, initially as dyspnea and fatigue.
- Study 2 reports on a group of 20 patients with a mean age of 64 years, ranging from 29 to 77 years, who underwent valvular surgery for carcinoid heart disease.
- There is no specific information provided about the gender distribution of patients affected by carcinoid heart disease in the given studies 2, 3, 4, 5, 6.
Clinical Characteristics
- Carcinoid heart disease primarily affects right heart valves, causing tricuspid and pulmonic regurgitation and less frequently stenosis of these valves 5.
- Left heart valves are usually spared because vasoactive substances such as serotonin are enzymatically inactivated in the lung vasculature 5.
- The pathology of carcinoid heart disease is characterized by plaque-like deposition of fibrous tissue on valvular cusps, leaflets, papillary muscles, chordae, and ventricular walls 5.