Retrospective comparison of ultrasound facilitated catheter-directed thrombolysis and systemically administered half-dose thrombolysis in treatment of pulmonary embolism.

This study retrospectively compared the outcomes of patients who received ultrasound facilitated catheter-directed thrombolysis (UFCDT) versus systemically administered 'half-dose' thrombolysis (HDT) in 97 patients with PE. The outcomes assessed included changes in baseline pulmonary artery systolic pressure (PASP), right ventricle/left ventricle ratio (RV/LV), cost and duration of hospitalization, death, bleeding, and recurrent venous thromboembolism in the short and intermediate term follow-up. Analyses were performed using a covariance adjustment propensity score approach to address baseline differences between groups in variables associated with PASP and RV/LV, covarying baseline scores. The baseline mean ± SE PASP dropped from 49.3 ± 1.1 to 32.5 ± 0.3 mmHg at 36 hours in the HDT group, and from 50.6 ± 1.2 to 35.1 ± 0.4 mmHg in the UFCDT group; group × time interaction p-value = 0.007. Corresponding drops in the RV/LV were from a baseline of 1.26 ± 0.05 to 1.07 ± 0.01 in the HDT group and from 1.30 ± 0.05 to 1.14 ± 0.01 in the UFCDT group at 36 hours; group × time interaction p-value = 0.269. Statistically significant decreases were noted in PASP and RV/LV for both the HDT and UFCDT at 36 hours and follow-up. PASP through follow-up was significantly lower in the HDT than the UFCDT group. Likewise, RV/LV was lower in the HDT group. The duration and cost of hospitalization were lower in the HDT group (6.2 ± 1.4 days vs 1.9 ± 0.3 days, p < 0.001; US$12,000 ± $3000 vs $74,000 ± $6000, p < 0.001). We conclude that both UFCDT and HDT lead to rapid reduction of PASP and RV/LV, whereas HDT leads to a lower duration and cost of hospitalization.