Post-Pneumonectomy Syndrome Causing Reversible Right Ventricular Dilation and Tricuspid Regurgitation

BACKGROUND: Post-pneumonectomy syndrome is a rare complication caused by excessive mediastinal shift and cardiac rotation, leading to nonspecific cardiopulmonary symptoms. CASE SUMMARIES: We report the cases of 2 patients who developed cardiopulmonary symptoms after having left pneumonectomy for lung cancer. In both cases, multimodality imaging demonstrated an early mediastinal displacement with cardiac rotation. Transthoracic and transesophageal echocardiography revealed right ventricular enlargement and new significant functional tricuspid regurgitation. Computed tomography confirmed the anatomic distortion and excluded other pathology. Symptoms were attributed to cardiac displacement, and both patients underwent surgical intervention for mediastinal repositioning with placement of an intrathoracic tissue expander. Intraoperative transesophageal echocardiography showed immediate improvement in right ventricular size and tricuspid regurgitation following expander placement, with sustained clinical and imaging improvement during follow-up. CONCLUSIONS: Post-pneumonectomy syndrome should be considered in patients with new right-heart abnormalities after surgery. Early recognition of this reversible condition is essential to guide appropriate management. TAKE-HOME MESSAGES: Post-pneumonectomy syndrome should be considered in patients with new cardiopulmonary symptoms and right-heart abnormalities following surgery. A high index of suspicion and multimodality imaging is critical for identifying cardiac rotation and distortion, which can be corrected.