BACKGROUND: Acute pulmonary embolism (APE) poses a significant risk to patient health, with treatment options varying in efficacy and safety. Ultrasound-facilitated catheter-directed thrombolysis (USCDT) has emerged as a potential alternative to conventional catheter-directed thrombolysis (CDT) for patients with intermediate to high-risk APE. This study aimed to compare the efficacy and safety of USCDT versus conventional CDT in patients with intermediate to high-risk APE.
METHODS: This observational retrospective study was conducted at the Armed Forces Hospital, Al-Hada, Taif, the Kingdom of Saudi Arabia (KSA), on 135 patients diagnosed with APE and treated with either USCDT or CDT (58 underwent CDT, while 77 underwent USCDT). The primary efficacy outcome was the change in the right ventricle to the left ventricle (RV/LV) diameter ratio. Secondary outcomes included changes in pulmonary artery systolic pressure and the Miller angiographic obstruction index score. Safety outcomes focused on major bleeding events.
RESULTS: Both USCDT and CDT significantly reduced RV/LV diameter ratio (from 1.35 ± 0.14 to 1.05 ± 0.17, P < 0.001) and systolic pulmonary artery pressure (SPAP) (from 55 ± 7 mmHg to 38 ± 7 mmHg, P < 0.001) at 48- and 12-hours post-procedure, respectively, with no significant differences between treatments. However, USCDT was associated with a significantly lower rate of major bleeding events compared to CDT (0% vs. 3.4%, P = 0.008). Multivariate logistic regression analysis revealed that USCDT was associated with a 71.9% risk reduction of bleeding (OR = 0.281, 95% CI = 0.126 - 0.627, P = 0.002).
CONCLUSIONS: USCDT is a safe and effective alternative to CDT for the treatment of intermediate to high-risk APE, as it significantly reduces the risk of major bleeding.

OBJECTIVE: There is an ongoing discussion on the optimal right to left (RV/LV) diameter ratio threshold and the best definition of RV dysfunction on computed tomography pulmonary angiography (CTPA) for risk assessment of pulmonary embolism (PE).
METHODS: On routine diagnostic CTPA, volumetric and diameter measurements (axial and reconstructed views) of the ventricles and reflux of contrast medium into the inferior vena cava (IVC) and hepatic veins were assessed in consecutive PE patients enrolled in a prospective single-center registry. In-hospital adverse outcome was defined as PE-related death, cardiopulmonary resuscitation, mechanical ventilation or catecholamine administration.
RESULTS: Of 609 patients (median age, 69 [IQR, 56-77] years; 47 % male) included in the analysis, 68 patients (11.2 %) had an adverse outcome and 35 (5.7 %) died. While neither a RV/LV volume ratio ≥1.0 nor RV/LV diameter ratios ≥1.0 were able to predict an adverse outcome, higher thresholds increased specificity. Further, neither volumetric measurements nor reconstruction of images provided superior prognostic information compared to RV/LV ratios measured in axial planes. The combination of an axial RV/LV diameter ratio ≥1.5 with substantial reflux of contrast medium was present in 134 patients (22 %) and associated with the best prognostic performance to predict an adverse outcome in unselected (OR 3.7 [95 % CI, 2.0-6.6]) and normotensive (OR 2.8 [95 % CI, 1.1-6.7]) patients.
CONCLUSIONS: A new definition of RV dysfunction (axial RV/LV diameter ratio ≥1.5 and substantial reflux of contrast medium to the IVC and hepatic veins) allows an optimized CTPA-based prediction of PE-related adverse outcome.

Objective: Current guidelines recommend utilization of catheter-directed thrombolysis systems for management of patients with submassive pulmonary embolism (PE) who have relative contraindications to systemic thrombolysis. Evidence from previous trials have demonstrated the short-term efficacy and safety of one of these systems, the EkoSonic Endovascular System (EKOS). The objective of this study was to evaluate the long-term efficacy and safety of EKOS in submassive PE. Methods: This single-center, retrospective study evaluated subjects ≥18 years old with submassive PE and baseline right ventricular to left ventricular (RV/LV) diameter ratio ≥1. The primary outcome evaluated change in RV/LV diameter ratio from baseline to first follow-up. The secondary outcomes evaluated need for further intervention after EKOS, major bleeding within 72 hours and 6 months, all-cause mortality at 6 months, and all-cause 30-day readmission rate. Results: Overall, 41 subjects received EKOS for submassive PE. Of the 26 subjects evaluated for the primary outcome, the RV/LV diameter ratio decreased by an average of 0.56 (P < 0.05). Of the 41 subjects evaluated for the secondary outcomes, 1 subject required pulmonary embolectomy after EKOS intervention, 1 major bleed occurred within 72 hours, 1 major bleed occurred within 6 months, 1 subject died within 6 months, and 3 subjects were readmitted within 30 days. Conclusions: Intervention with EKOS further reduced right heart strain and resulted in few complications compared with previous trials providing evidence that EKOS is effective and safe long-term for management of submassive PE. Use should be considered in patients with relative contraindications to systemic thrombolytic therapy.