Solomon Ocran, DO; Mukul Sharda, BS; Charles Haynes, MD; Pinky Jha, MD, MPH
WMJ. 2026;125(4):526-528. Published November 1, 2026.
ABSTRACT
Introduction: Intimomedial mucoid degeneration (IMMD) is a rare noninflammatory arteriopathy classically affecting young Black African women with hypertension.
Case Presentation: A 34-year-old White man with chronic tobacco use presented with progressive dyspnea initially attributed to multifocal pneumonia and pulmonary edema. Computed tomography revealed bilateral pulmonary infiltrates and a 6.2-cm ascending aortic aneurysm with a pericardial effusion. Echocardiography demonstrated severe aortic regurgitation. During hospitalization, he developed chest pain and asymmetric pulses; computed tomography angiography confirmed an acute arch dissection. Emergent valve-sparing aortic root replacement, total arch repair, and descending thoracic stent graft placement were performed. Histopathologic examination confirmed IMMD.
Discussion: This case expands the demographic profile of IMMD and illustrates its potential to mimic pulmonary infection, delaying recognition of underlying cardiovascular disease. The recent COVID-19 infection in this patient raises the theoretical possibility that viral-induced endothelial injury contributed to aortic wall degeneration, although this association remains speculative and warrants further investigation.
Conclusions: Clinicians should consider structural cardiovascular disease in patients with unexplained dyspnea or presumed pneumonia unresponsive to antibiotic therapy, particularly when cardiac murmurs are present or imaging reveals mediastinal abnormalities. Early recognition, prompt surgical intervention, and histopathologic confirmation are essential for favorable outcomes in patients with IMMD.