Continuous mechanical aspiration thrombectomy performs equally well in main versus branch pulmonary emboli: A subgroup analysis of the EXTRACT‐PE trial

INTRODUCTION: The EXTRACT-PE trial evaluated the safety and performance of the Indigo Aspiration System (Penumbra Inc.) with an 8F continuous mechanical aspiration thrombectomy system for the treatment of pulmonary embolism (PE). This subgroup analysis evaluates performance outcomes of patients with main pulmonary artery (PA) emboli versus discrete unilateral or bilateral PA emboli without main PA involvement. METHODS: The EXTRACT-PE trial was a prospective, single-arm, multicenter trial that enrolled 119 patients with acute submassive PE. Emboli location was collected at the time of enrollment, CT obstruction was measured and assessed by a Core Lab, and patients were grouped on whether emboli involved the main PA (with or without branch vessels) or not (branch vessels alone). Procedural device time, changes in the right ventricle to left ventricle (RV/LV) ratio, and systolic PA pressure from pre-and posttreatment were compared between the two groups. RESULTS: Out of the 119 patients enrolled, 118 had core lab-assessed clot locations. Forty-five (38.1%) had emboli that involved the main PA and 73 (61.9%) had only branch emboli. No significant difference was observed between these groups for 30-day mortality, procedural device time, changes in RV/LV ratio, reduction in CT Obstruction Index, or for systolic PA pressure from pre-and posttreatment. The mean absolute reduction in clot burden was significant in both groups. CONCLUSION: Continuous mechanical aspiration thrombectomy with the 8F Indigo Aspiration System was effective at improving clinical outcomes for submassive PE patients regardless of emboli location, and clot burden was significantly reduced in both groups.