Carcinoid heart disease of gonadal primary presenting with hypoxia: a case report

BACKGROUND: Carcinoid heart disease is a potential sequela of metastatic neuroendocrine tumour that has characteristic valve appearances. Patients can present with symptoms of carcinoid syndrome or be relatively asymptomatic until symptoms of progressive heart failure manifest. CASE SUMMARY: We present a case of a 54-year-old male who was admitted to the hospital for investigation of hypoxia. Transthoracic echocardiogram was suggestive of carcinoid heart disease which subsequently led to a diagnosis of metastatic neuroendocrine (carcinoid) tumour of the testicular primary. Work-up revealed a patent foramen ovale with evidence of the right to left interatrial shunt from severe tricuspid regurgitation as the cause of his hypoxia. Prior to surgical excision of the primary tumour, percutaneous patent foramen ovale closure was performed resulting in improved arterial oxygen saturation and symptomatic improvement. DISCUSSION: Carcinoid heart disease typically affects the right-sided cardiac valves and the tricuspid valve appearances were critical in leading to a diagnosis of a metastatic neuroendocrine tumour in our patient. This case demonstrates that percutaneous patent foramen ovale closure can be an effective intervention for hypoxia in those not managed surgically. A high index of suspicion should be maintained for gonadal primary carcinoid tumour when there is carcinoid heart disease in the absence of liver metastases.