Multivalvular Carcinoid Heart Disease: The Role of Echocardiography in Diagnosis and Selection for Heterotopic Bicaval Valve Implantation

Background and Clinical Significance: Carcinoid heart disease (CHD) is an uncommon valvular manifestation of neuroendocrine tumours, usually affecting right-sided cardiac valves. Left-sided involvement is rare and is generally associated with bronchopulmonary carcinoid, right-to-left shunting, or markedly elevated circulating vasoactive substances. Therapeutic decision-making is particularly challenging in advanced disease when severe tricuspid regurgitation occurs in patients at prohibitive surgical risk. Case Presentation: We report the case of a 61-year-old male patient with progressive dyspnoea, abdominal distension, lower-limb oedema, facial flushing, and 15 kg of unintentional weight loss. Transthoracic and transoesophageal echocardiography demonstrated torrential tricuspid regurgitation caused by thickened, retracted, and immobile leaflets, with additional mitral and aortic valve involvement, raising strong suspicion of CHD. An agitated-saline contrast study demonstrated delayed right-to-left shunting without patent foramen ovale, suggesting an extracardiac, likely intrapulmonary, shunt. Somatostatin receptor PET/CT identified a pancreatic lesion with metastatic disease, and bone marrow biopsy confirmed neuroendocrine tumour infiltration. Owing to prohibitive surgical risk, as reflected by a Tricuspid Regurgitation Impact Score (TRI-SCORE) with an estimated in-hospital mortality of 65%, unfavourable tricuspid anatomy for repair, and refractory venous congestion, heterotopic bicaval valve implantation was performed (TricValve system -P&F). Discussion: This case highlights the role of echocardiography in recognising the characteristic phenotype of CHD, detecting occult right-to-left shunting, and supporting selection of a palliative transcatheter intervention. It also illustrates the value of a multimodality diagnostic strategy integrating echocardiography, functional oncological imaging, and histopathology in tumour-related cardiac disease. Conclusions: In selected inoperable patients with advanced carcinoid-related tricuspid regurgitation, heterotopic bicaval valve implantation may represent a feasible strategy for reducing venous congestion and improving functional status.