Tricuspid Valve Regurgitation as a Presenting Symptom of Metastasized Carcinoid Tumor

A 66-year-old woman was diagnosed with hepatic metastasized carcinoid tumor of the ileocecal junction resulting in elevated plasma chromogranin A levels and urinary 5-hydroxyindoleacetic acid (5-HIAA) levels. Further examination showed right-sided heart failure with severe tricuspid valve regurgitation. Carcinoid tumors produce serotonin which leads to flushing, secretory diarrhea, bronchospasm and hypotension, known as carcinoid syndrome. Serotonin is metabolized to 5-HIAA, which is inactive, in the liver and the lungs. However, hepatic metastases may result in direct exposure of the heart to serotonin, which induces plaque-like deformities on the tricuspid valve, and in turn induces valve regurgitation. This condition is known as carcinoid heart disease. Tricuspid valve regurgitation may induce risk of massive blood loss in case of liver surgery through high-volume backflow in the hepatic veins. This report shows the clinical relevance of carcinoid heart disease in the perioperative setting.