Massive Pulmonary Embolism Presenting as Recurrent Cardiac Arrest: Successful Resuscitation and Thrombolysis in a 74-Year-Old Male.

Massive pulmonary embolism (PE) is a life-threatening emergency often presenting with hemodynamic collapse or cardiac arrest. Despite advances in resuscitation and reperfusion therapies, outcomes remain poor. We report the case of a 74-year-old man with a history of hypertension, hyperlipidemia, and diabetes mellitus who presented with acute severe dyspnea leading to pulseless electrical activity (PEA) cardiac arrest. Return of spontaneous circulation was achieved with advanced cardiac life support, but he subsequently experienced recurrent PEA arrest requiring intubation, vasopressors, and antiarrhythmic therapy. Electrocardiography showed sinus tachycardia with right bundle branch block and repolarization abnormalities. Laboratory evaluation revealed marked troponin elevation, leukocytosis, thrombocytopenia, and hypokalemia. Duplex ultrasound demonstrated bilateral lower extremity deep vein thromboses. Echocardiography showed preserved left ventricular function with an enlarged, hypokinetic right ventricle and apical sparing. Chest computed tomography angiography revealed a large burden of bilateral pulmonary emboli with right ventricular strain and wedge-shaped pulmonary infarctions. The patient was treated with systemic thrombolysis (tenecteplase), complicated by transient oral and urinary bleeding that resolved spontaneously. Over several days, he stabilized, was weaned from vasopressors and mechanical ventilation, and discharged on full anticoagulation to outpatient follow-up. This case highlights the diagnostic challenge of massive PE, the value of bedside echocardiography, and the importance of prompt reperfusion therapy in unstable patients.