Introduction:
Ultrasound-assisted catheter-directed thrombolysis using the EkoSonic Endovascular System (EKOS) is an established treatment option for intermediate high-risk pulmonary embolism (IHR-PE). Although sex-related differences have been described in acute PE, their impact on outcomes following EKOS therapy remain scarce.
Aim:
To evaluate sex-specific differences in safety and efficacy among patients undergoing EKOS therapy for IHR-PE.
Methods:
This retrospective multicentre analysis included consecutive patients with IHR-PE undergoing EKOS thrombolysis at 3 different sites in Germany between August 2020 and December 2023.
Patients were stratified according to sex. Efficacy was assessed by changes in echocardiographic markers of right ventricular overload from admission to discharge and follow-up, including right ventricular to left ventricular ratio (RV/LV), tricuspid annular plane systolic excursion (TAPSE), systolic pulmonary artery pressure (sPAP) and right ventricular end diastolic diameter (RVEDd). Safety endpoints included procedure- and PE-related complications, in-hospital mortality and intensive care unit (ICU) stay.
Results:
We included a total of 154 patients, 74 (48.1%) men and 80 (51.9%) women. Men had higher hemoglobin levels (13.4 vs. 13.0 g/dl, p<0.001) and higher creatinine levels (101 vs. 87 µmol/l, p=0.018). Hormone replacement therapy was present in 8.8% of women. No other significant differences in baseline characteristics were observed. Both sexes demonstrated significant improvement in echocardiographic markers of RV function (p<0.001) from admission to discharge and further to follow-up. The magnitude of improvement from admission to discharge was comparable between men and women (ΔRV/LV −0.332 ± 0.20 vs. −0.335 ± 0.30; p=0.659). Similarly, TAPSE improvement (ΔTAPSE +4.8 ± 5 mm vs. +4.1 ± 5 mm; p=0.505), sPAP reduction (ΔsPAP −14.4 ± 11 mmHg vs. −12.7 ± 14 mmHg; p=0.959) and RVEDd reduction (ΔRVEDd −8 ± 6.3 mm vs. −9 ± 7 mm, p=0.303) did not differ between sexes. The observed improvements remained consistent at follow-up, with no significant differences between men and women regarding ΔRV/LV (−0.484 ± 0.30 vs. −0.459 ± 0.28, p=0.748), ΔTAPSE (+6.4 ± 7 mm vs. +6.0 ± 6 mm, p=0.792), ΔsPAP (−21.1 ± 11 mmHg vs. −18.3 ± 11 mmHg, p=0.449) and ΔRVEDd (−13 ± 7.6 mm vs. −12.5 ± 7 mm, p=0.249). Women experienced significantly more overall complications than men (21.3% vs. 9.5%, p=0.044). Bleeding complications were numerically more frequent in women (18.8% vs. 8.1%, p=0.063), particularly procedure-related bleeding events (15.0% vs. 6.8%, p=0.126). In-hospital mortality was comparable between women and men (7.5% vs. 5.4%, p=0.748). ICU stay was significantly longer in men (42 ± 33 h vs. 34 ± 30 h, p=0.016).
Conclusion:
In patients with IHR-PE undergoing EKOS-lysis, women experienced more complications, with a numerical excess of bleeding events, whereas men required longer ICU treatment. However, mortality and recovery of RV function were comparable between sexes. These findings suggest comparable efficacy of EKOS-lysis in both sexes despite differences in safety outcomes. Prospective studies are warranted to further evaluate these findings.
