Short Duration Catheter-directed Thrombolysis for Acute Pulmonary Embolism Rapidly Improves Acute Cardiac Function

Abstract

Background: Treatment of massive and submassive pulmonary embolism (PE) has been shown to be a valuable therapeutic modality. However, a paucity of data exists, regarding length and guidelines for treatment and typically these patients are treated by other than vascular surgery specialists. The aim of this study is to evaluate the effectiveness and safety of short duration treatment of massive and submassive PE, exclusively by vascular surgeons, without routine follow-up pulmonary angiography.

Methods: Retrospective analysis of prospectively collected data at a single-institution treating massive and submassive PE with catheter-directed thrombolysis (CDT). Internal review board approval was obtained. Descriptive statistical analysis was performed from the data set. Continuous covariates were presented in mean (SD) or median (IQR) and categorical covariates as number (percentage). For continuous variables, a paired t test was used to measure results against the baseline. P value less than 0.05 was defined as statistically significant. STATA® statistical software was used for analysis.

Results: From January of 2013 to December of 2016, 28 consecutive patients were treated for massive and submassive PE with CDT. All patients had evidence of right heart strain on echocardiogram, as evidence by a right ventricular to left ventricular (RV/LV) diameter ratio of >0.9. Of the 28 patients, 19 (68%) had hemodynamic derangement with either systolic blood pressure (SBP) less then 90 or tachycardia (HR > 100). The mean RV/LV ratio before CDT was 1.18. After therapy, RV/LV ratio was reduced to 0.86 at 48 hr (P < 0.0001). In addition, mean right ventricular systolic pressure (RVSP) before CDT treatment was 53 mm Hg, and after treatment, RVSP was reduced to 40 mm Hg at 48-hr (P value = 0.0001). There was complete resolution of hypotension in hemodynamically unstable patients (i.e., SBP <90) after CDT. Mean HR before therapy was 102. After 24 hr of CDT, mean HR reduced to 84 (P < 0.0001). From 2013 to 2016, there was a significant decrease in mean hospital length of stay from 8 days to 4 days (P = 0.05). Mean t-PA dose used decreased, as well, from 2014 (21.7 mg) to 2016 (14.9 mg), but this was not statistically significant (P = 0.13). There was no major bleeding complications or CDT-related death in any of the patients treated during the study period.

Conclusions: CDT treatment of massive and submassive PE is safe and highly efficacious at reducing right heart strain acutely. Significant hemodynamic improvement was shown in our cohort throughout the study period. Improvement in tachycardia and resolution of hypotension were seen within 24 hr of CDT. Tissue plasminogen activator dosage decreased throughout the study period as a more restrictive approach to follow-up angiography was used without adverse safety or patient outcomes.