Short-term outcomes of ultrasound-assisted catheter-directed thrombolysis and mechanical thrombectomy in management of intermediate-risk pulmonary embolism.

OBJECTIVE

The aim of this study was to compare preoperative right ventricle-to-left ventricle (RV/LV) ratios by computed tomography angiography (CTA) and echocardiography and evaluate treatment outcomes of ultrasound-assisted catheter-directed thrombolysis (USAT) or mechanical thrombectomy (MT) in patients with intermediate-risk pulmonary embolism (PE).

METHODS

We retrospectively identified patients treated for intermediate-risk PE from 2018 to 2023 defined by systolic blood pressure (BP) >90 mmHg and right ventricle dysfunction defined by RV/LV ratio >0.9 via echocardiogram. RV/LV ratios were also evaluated on diagnostic CTA for comparison to echocardiogram values. Patients underwent USAT or MT based on thrombus location and contraindications to thrombolysis. Primary outcomes were intensive care unit (ICU) length of stay (LOS), hospital LOS, and 30-day and 1-year survival. Secondary outcomes included RV/LV change post-treatment on echocardiography, concomitant deep vein thrombosis (DVT), elevated cardiac biomarkers, blood transfusion, history of DVT/PE or malignancy, and imaging modality comparison in determination of RV/LV and RV/LV changes.

RESULTS

Of 120 patients from a single center treated for intermediate-risk PE, 100 underwent USAT and 20 MT. There was no difference in ICU LOS (2.4 vs 2.6 days; P = .67) or hospital LOS (4.8 vs 5.7 days; P = .41) for USAT and MT, respectively. There was no difference in 30-day (98% vs 100%), or 1-year survival (96% vs 90%). MT patients had greater incidence of blood transfusion (25% vs 5%; P = .011). CTA overestimated RV/LV ratios preoperatively compared with echocardiography (1.4; SD, 0.4 vs 1.3; SD, 0.2; P = .027). Patients undergoing MT were more likely to have identified lower extremity DVT compared with patients undergoing USAT (90% vs 65%; P = .033). Other secondary outcomes showed no significant differences between treatment groups.

CONCLUSIONS

Both USAT and MT provide excellent short-term and intermediate outcomes in patients with intermediate-risk PE, similar survival rates, similar post-treatment change in right heart dysfunction, and comparable ICU and hospital stays. MT is associated with higher transfusion rates, so caution should be exercised in patients felt to be at risk from further blood loss. These findings support individualized, anatomy- and risk-based selection of catheter-based therapy within a multidisciplinary PE response framework.