Isolated Unilateral Absence of Right Pulmonary Artery: Presenting with Dyspnea and Mimicking Pulmonary Embolism

Abstract

Introduction: Isolated unilateral absence of pulmonary artery (IUAPA) is a rare congenital anomaly characterized by diverse and nonspecific clinical manifestations. It is often misdiagnosed or remains undetected. This report presents a case of IUAPA in a previously healthy male, where dyspnea was the sole dominant symptom. The clinical presentation of unexplained dyspnea and the chest X-ray findings in this patient closely resembled those of a pulmonary embolism. Computed tomographic (CT) pulmonary angiography was instrumental in differentiating between these two conditions. Case Presentation: A 38-year-old male, previously in good health, began experiencing progressive dyspnea on exertion four months prior to admission. A chest X-ray revealed an absent right hilar shadow, reduced volume of the right lung, diminished vascular markings over the right lung, deviation of the trachea to the right side, and elevation of the right hemidiaphragm. These findings, combined with the unexplained dyspnea, led to a suspicion of pulmonary embolism. However, subsequent investigation using CT pulmonary angiography confirmed a diagnosis of isolated unilateral absence of the right pulmonary artery. Conclusions: This case highlights an instance of isolated unilateral absence of the right pulmonary artery, which mimicked pulmonary embolism in terms of clinical symptoms, chest roentgenograph, and ventilation/perfusion (V/Q) lung scan perspectives. It is crucial for clinicians to recognize the characteristic chest X-ray findings that may suggest IUAPA. A high index of clinical suspicion is essential for early diagnosis and effective management.