Effects of Early Versus Delayed Mechanical Thrombectomy on Outcomes in Intermediate-Risk Acute Pulmonary Embolism.

OBJECTIVES: Evidence guiding the optimal timing of mechanical thrombectomy for patients presenting with intermediate-risk pulmonary embolism (PE) is limited. We aimed to evaluate whether the timing of mechanical thrombectomy is associated with improved clinical outcomes in this patient population.

DESIGN, SETTING, AND PATIENTS: This multicenter, retrospective cohort study was conducted at five large academic hospitals. In total, 290 patients presenting with intermediate-risk PE who were treated with mechanical thrombectomy were included for analysis. The primary outcome was in-hospital mortality. Using generalized estimated equation, we compared the odds of in-hospital mortality for patients undergoing early intervention (EI; mechanical thrombectomy < 12 hr after PE diagnosis) vs. those undergoing delayed intervention (DI; mechanical thrombectomy ≥ 12 hr after diagnosis) while comparing for PE severity and other confounders.

INTERVENTIONS: None.

MEASUREMENTS AND MAIN RESULTS: EI was performed in 179 patients (61.7%), while 111 patients (38.3%) received DI. Unadjusted mortality did not differ significantly between groups (7.3% [13/179] vs. 10.8% [12/111]; p = 0.39). After adjusting for the Pulmonary Embolism Severity Index and Composite Pulmonary Embolism Shock scores, timing of intervention did not influence mortality (odds ratio, 1.80; 95% CI, 0.82-3.95; p = 0.14). However, patients in the EI group had greater reductions in in pulmonary artery systolic pressure (-25.8% [17.0] vs. -18.9% [17.1]; p = 0.020 and mean pulmonary artery pressure, -26.8% [17.7] vs. -20.2% [19.7]; p = 0.016) and lower rates of intubation (8.9% [16/179] vs. 18% [20/111]; p = 0.028).

CONCLUSIONS: In patients presenting with intermediate-risk PE, timing of mechanical thrombectomy did not influence in-hospital mortality. EI may result in greater reductions in pulmonary artery pressures and decreased incidence of intubation compared with DI.