Massive Bilateral Pulmonary Thromboembolism Due to a Thrombus in Transit to the Right Atrium: A Case Report

A 48-year-old man presented to a rural Honduran hospital with progressive dyspnea for three days, worsening at rest. He was hemodynamically stable and without tachypnea or pulmonary crackles. The electrocardiogram showed sinus tachycardia, suggestive of pulmonary thromboembolism (PTE). Chest CT confirmed the diagnosis of bilateral PTE with total occlusion of the right pulmonary artery and significant stenosis of the left pulmonary artery. Transthoracic echocardiogram revealed a right atrial thrombus. Medical treatment with therapeutic anticoagulation was provided. Echocardiographic follow-up at 10 days showed that the original thrombus had been significantly reduced to two smaller thrombi. The patient was discharged from the hospital with more anticoagulants. Thrombus in transit alongside pulmonary embolism is rare and is an emergent condition; it can quickly progress to cardiogenic shock or cardiac arrest. This patient's effective diagnosis and treatment highlight the importance of bedside echocardiography in resource-limited settings.