Successful Catheter-Directed Thrombolysis for a Patient With Intermediate-High-Risk Pulmonary Embolism: A Case Report

Acute pulmonary embolism (PE) is a prevalent cardiovascular condition with significant mortality and morbidity. Treatment strategies vary according to risk stratification. While anticoagulation is sufficient for low-risk patients, high-risk cases often necessitate systemic thrombolysis (ST) or surgical embolectomy. Catheter-directed therapy (CDT) has emerged as an alternative for high- and intermediate-high-risk patients, particularly when ST is contraindicated or poses a high bleeding risk. Through CDT, thrombolytic drugs are locally delivered straight into the pulmonary arteries. Despite promising outcomes in select cases, evidence for CDT remains inconclusive, reflected in its class-IIa recommendation in current guidelines. We describe a 44-year-old male who experienced sudden and worsening dyspnea over 5 days. The patient had a history of smoking, methadone addiction, and a recent motor vehicle accident, with a prior intracranial hemorrhage. Echocardiography revealed right ventricular dilation and systolic dysfunction, and computed tomography pulmonary angiography confirmed massive bilateral pulmonary artery thrombosis, while the patient's troponin level was 996 ng/L (reference < 2), categorizing the patient as intermediate-high risk. Due to contraindications to systemic thrombolysis and lack of response to anticoagulation, CDT was performed, resulting in rapid improvement in symptoms, oxygenation, and right ventricular function. The patient was discharged without complications. He was transitioned to oral anticoagulation and remained stable at three-month follow-up. This case highlights the potential of CDT as an effective and safe treatment for PE patients with intermediate-to-high risk who are not candidates for ST, a scenario with limited therapeutic options. CDT's routine use requires validation through additional studies and randomized trials.