Open Heart. 2026 Jun 22;13(1):e004271. doi: 10.1136/openhrt-2026-004271.
ABSTRACT
BACKGROUND: Ultrasound-assisted catheter-directed thrombolysis using the EkoSonic Endovascular System (EKOS) is an established treatment for intermediate high-risk pulmonary embolism (IHR-PE). However, the optimal timing of treatment initiation remains uncertain. Early right ventricular (RV) unloading may improve outcomes by reducing RV pressure overload and preventing haemodynamic deterioration.
METHODS: We conducted a retrospective multicentre analysis of patients with IHR-PE treated with EKOS at three tertiary centres. Patients were stratified by time from CT-confirmed diagnosis to EKOS initiation: early (<12 hours) versus delayed (>12 hours). Echocardiographic parameters included RV/left ventricular (LV) ratio, tricuspid annular plane systolic excursion (TAPSE), LV ejection fraction (LVEF) and systolic pulmonary artery pressure (sPAP). Secondary outcomes were intensive care unit (ICU) length of stay, complications, bleeding events and in-hospital mortality. 3-month follow-up was available in two centres.
RESULTS: Overall, 152 patients were included (early n=106; delayed n=46) in the study. Baseline characteristics were largely comparable, although dyspnoea New York Heart Association (NYHA) class II-III was more frequent in the early group (NYHA III: 73% vs 46%, p=0.001). Both groups showed significant improvements in RV/LV ratio, TAPSE, sPAP and LVEF (all p<0.001). Early treatment resulted in numerically greater RV functional improvement (Early Δ Discharge (D)-Admission (A) TAPSE early 4.86±5.14 mm vs delayed Δ D-A 3.5±5 mm), without statistically significant differences between groups. At 3-month follow-up, RV recovery measured by TAPSE was comparable. Early EKOS therapy was associated with a significantly shorter ICU stay (median 24 hours vs 45.5 hours, p=0.033), fewer PE-related complications (p=0.03), while procedure-related complications and in-hospital mortality did not differ.
CONCLUSIONS: In IHR-PE, EKOS initiation within 12 hours is associated with a significantly shorter ICU stay and significantly less PE-related complications. These findings support early EKOS treatment strategies and warrant confirmation in prospective studies.
PMID:42331566 | DOI:10.1136/openhrt-2026-004271