Carcinoid heart disease and the gold standard for pulmonary valvular heart surgery: gold may not be so bright, a case series

Carcinoid tumors are neuroendocrine tumors often resulting in a clinical syndrome of diarrhea, flushing, and bronchospasm known as carcinoid syndrome. While this syndrome is seen in around one in ten individuals, carcinoid heart disease (CHD) with valvular pathologies can be the first sign of this condition in around every one in five individuals. Definitive treatment with valvular surgery is required to reduce mortality [1-4]. The current gold standard for any pulmonary valve surgery involves cryopreserved homografts, which have been shown to be more durable, have lower transvalvular gradients, and have lower risk for reintervention [5]. This case series presents four patients with CHD on guideline directed oncologic treatment requiring valvular heart surgery for further management. While two patients had classical carcinoid symptoms, the other two presented solely with valvular pathology. One patient had left-sided valvular pathology in contrast to the remaining patients (see table 1). Initial evaluation of all patients included a transthoracic echocardiogram (TTE) followed by transesophageal echocardiogram (TEE) and chest CT angiogram for confirmation and procedural planning. Preoperative coronary angiography was also performed without significant coronary lesions. All four patients subsequently underwent valvular replacement surgery with perioperative octreotide infusion. Patient one underwent mitral valve replacement with bioprosthetic porcine valve. Post-operative TTE showed improved mean gradient, remaining stable until the patient’s passing from COVID-19. The other three patients had replacements of pulmonic valve with homograft (2) and one with transcatheter bioprosthetic valve. Two of three patients also had tricuspid valve replacement with bioprosthetic valve. Immediately post-operatively, all three patients had excellent outcomes with improvement in mean gradients across both bioprosthetic valves and homografts. However, upon follow up 1-3 months later, pulmonary homografts showed worsening function with recurrence of severe regurgitation, while bioprosthetic tricuspid valves in all three patients remained stable. By serving as their own control, these patients suggest that homografts may be more susceptible to damage in carcinoid heart disease. In summary, CHD is a major clinical complication of carcinoid tumors associated with significant increases in morbidity and worse quality of life [1]. Here we presented the successful management of four patients with CHD through valvular replacement without any significant short term complication and overall improvement in quality of life. However, worsening in the gold standard of pulmonary homografts is concerning for susceptibility of these valves in carcinoid heart disease. We hypothesize that bioprosthetic pericardial valves including transcatheter alternative may convey lower gradients and longer durability. Larger samples are required as this may modify practice patterns.Patient demographics and outcomes Carcinoid heart disease echocardiogram