Rapid Onset of Pulmonary Arterial Hypertension After Liver Transplant—A Case Report

<b>Background and Clinical Significance</b>: Pulmonary hypertension (PH) is a recognized complication of chronic liver disease, most commonly manifesting as portopulmonary hypertension (POHP) prior to liver transplantation. While the natural history and management of pre-transplant PH are well described, the development of <i>de novo</i> pulmonary arterial hypertension (PAH) following liver transplantation remains exceedingly rare and poorly understood. In such cases, establishing true causality is challenging, and alternative explanations-including previously unrecognized or masked disease-must be carefully considered. This entity poses significant diagnostic and therapeutic challenges and may adversely affect post-transplant outcomes if not promptly recognized and treated. <b>Case Presentation</b>: We report the case of a 46-year-old man with end-stage liver disease secondary to alcohol use who underwent deceased donor liver transplantation without preoperative evidence of PH. His pre-transplant evaluation revealed preserved biventricular function and no measurable PH. Eight days postoperatively, he was readmitted with acute dyspnea, hypoxemia, and signs of right ventricular failure. Transthoracic echocardiography demonstrated severe right ventricular dilation and dysfunction with markedly elevated pulmonary artery systolic pressure. Right heart catheterization confirmed severe PAH. Secondary causes of PH were excluded. The patient was initiated on sildenafil and continuous intravenous epoprostenol, resulting in clinical, echocardiographic, and hemodynamic improvement. Subsequent follow-up demonstrated sustained response to therapy despite concurrent progression of coronary artery disease requiring complex percutaneous intervention. <b>Conclusions</b>: This case highlights a rare presentation of severe PAH occurring shortly after liver transplantation, in the absence of documented pre-transplant PH. While a causal relationship cannot be definitively established, the temporal association raises important clinical considerations. It underscores the need for heightened clinical vigilance for pulmonary vascular disease in post-transplant patients presenting with cardiopulmonary symptoms. Further research is warranted to elucidate the underlying mechanisms, risk factors, and optimal management strategies for PAH diagnosed after liver transplantation.