Pulmonary vein thrombosis: Clinical presentation and outcomes

Background Pulmonary vein thrombosis (PVT) is a rare thromboembolic disease with potential high-risk complications related to arterial embolization, but little is known regarding risk factors and outcomes. Objective To describe the etiology, management, and clinical course of PVT. Methods Institutional health records were queried (1/1/2001–12/30/2023) to identify patients ≥18 years of age diagnosed with PVT. Thrombosis, bleeding, respiratory failure, and all-cause mortality were analyzed. Suspected tumor thrombus cases were excluded. Results 72 patients with PVT were identified (median age 62 years, 50 % female), and PVT was overall rare at 3.1 diagnosed cases per year at our institution. PVT primarily affected a single vein (89 %), most commonly the left upper PV (40 %). Of these, 37 % occurred while on therapeutic anticoagulation. The most common risk factors included cancer (55 %) and related surgical lobectomy (21 %). Extrinsic vein compression (17 %) and recent surgery (19 %) were also common; 19 % were deemed idiopathic. Most patients (76 %) were treated with anticoagulation and frequently indefinite duration (80 %). During a median follow-up of 11.7 months (IQR 39.5 months), serial imaging (available for 68 %) revealed PVT resolution in 64 %. Four-year Kaplan-Meier probability of outcome included: left atrial thrombus (21 %), need for mechanical ventilation (14 %), pneumonia (9 %), and ischemic stroke (9 %). The mortality rate was 46 % with median survival 14 months after PVT diagnosis. Conclusion PVT is often associated with active malignancy, lobectomy, recent surgery, and extrinsic vein compression; 1 in 5 cases were idiopathic. Notable complications include left atrial thrombus with arterial embolism including stroke. With anticoagulation, most thrombi resolve over time. Mortality rates are high, reflecting the high the prevalence of cancer.