B50-04 ST-Segment Elevation and Brugada Phenocopy as a Manifestation of Tension Pneumothorax in Necrotizing Pneumonia With Bronchopleural Fistula

Introduction ST-segment elevation is a critical finding that typically indicates acute coronary syndrome and necessitates immediate evaluation. Extracardiac conditions such as tension pneumothorax may rarely produce pseudo-infarction patterns that mimic ST-elevation myocardial infarction (STEMI). In rare instances, they may also produce Brugada phenocopy, a reversible Brugada-like electrocardiographic pattern triggered by extracardiac pathology. We present a case of necrotizing pneumonia, complicated by bronchopleural fistula and tension pneumothorax, presenting with anterior ST-segment elevation and a Brugada-like pattern, with non-obstructive coronary arteries on angiography, highlighting a reversible STEMI mimic and suspected Brugada phenocopy secondary to tension pneumothorax. Case Presentation 46-year-old man with Hirschsprung disease and chronic megacolon admitted with acute hypoxemic respiratory failure secondary to influenza A pneumonia with superimposed necrotizing Streptococcus pneumoniae infection. He developed septic shock and acute respiratory distress syndrome requiring prolonged mechanical ventilation, neuromuscular blockade, and prone position-ventilation. Shortly after supination from a prone position, the patient developed sudden hemodynamic decompensation, with escalating vasopressor requirements. Electrocardiography (ECG) revealed a new right bundle branch block and coved ST-segment elevations in leads V1 through V3 [Figure 1]. Emergent coronary angiography demonstrated normal coronary anatomy, but a large right-sided pneumothorax was visualized during fluoroscopy. Chest tube placement led to prompt resolution of the ST-segment elevations. Persistent air leak following decompression raised suspicion of a bronchopleural fistula. Despite temporarily improving, the patient continued to decline over the forthcoming days clinically, with progressive shock and multiorgan failure. He was transitioned to comfort-directed care and passed shortly thereafter. Discussion Tension pneumothorax is a rare, life-threatening extracardiac cause of pseudo-infarct electrocardiographic patterns. These patterns may mimic ST-segment elevation or, in rare cases, cause transient Brugada-like electrocardiographic patterns, termed Brugada phenocopy. Proposed pathophysiologic mechanisms include hyper-acutely increased intrathoracic pressure, impaired venous return, elevated pulmonary vascular resistance, and reduced left-ventricular filling. In this case, necrotizing pneumonia led to a spontaneous bronchopleural fistula and tension pneumothorax, presenting with anterior STEMI. Coronary angiography showed no obstructive disease, and electrocardiographic changes resolved after pleural decompression, consistent with a reversible extracardiac process. Brugada phenocopy was suspected based on ECG morphology and clinical context. Ultimately, this case illustrates the development of Brugada phenocopy secondary to tension pneumothorax, an extracardiac mimic of STEMI, and highlights the importance of emergent coronary angiography to evaluate for obstructive disease and integrating clinical context and non-invasive testing in the consideration of patients with normal coronary anatomy in the diagnostic evaluation of ST-segment elevation in the critically ill.