When the Lungs Deceive: The Fatal Course of a Hidden Pulmonary Vein Thrombus

Abstract

Background: Pulmonary vein thrombosis (PVT) is a rare yet critically perilous vascular condition, frequently eluding timely diagnosis due to its protean clinical manifestations. While typically linked to underlying pathologies such as malignancy, thoracic surgical interventions, or atrial fibrillation ablation, PVT can, in exceptionally rare instances, manifest idiopathically. This report details an unusual case of acute respiratory failure attributable to PVT in a previously robust woman, notably devoid of conventional risk factors.
Case presentation: A 54-year-old woman, with no significant past medical or surgical history, presented to the emergency department exhibiting rapidly progressive dyspnea, profound fatigue, pleuritic chest pain, and palpitations. Upon admission, she displayed severe hypoxemia (SpO2 70% on room air), marked tachycardia, fever, and tachypnea. Comprehensive initial diagnostic evaluations, including imaging and laboratory analyses, effectively excluded more common etiologies such as pulmonary embolism, pneumonia, and COVID-19. Despite aggressive supportive measures and mechanical ventilation, her clinical course rapidly deteriorated, complicated by unstable atrial fibrillation and progressive multi-organ failure, culminating in her demise on the fifth day of hospitalization. Transesophageal echocardiography (TEE) definitively established the diagnosis of pulmonary vein thrombosis, with extension into the left atrium. Although hypercoagulability screening was initiated and systemic anticoagulation commenced, these interventions proved insufficient. The patient ultimately succumbed to intractable shock and widespread multi-organ dysfunction.
Conclusion: This compelling case profoundly highlights the imperative of including PVT in the differential diagnosis for patients presenting with severe, unexplained hypoxemia and signs of right heart failure, particularly when initial conventional imaging studies yield inconclusive results. Timely echocardiographic assessment and the immediate initiation of anticoagulation hold the potential to be life-saving, though the overall prognosis for such fulminant presentations remains exceedingly grave.