Table 5. Recent trials of ultrasound-assisted catheter-directed thrombolysis in patients with pulmonary embolism^109,115,116.

	ULTIMA	SEATTLE II	OPTALYSE PE
Publication year	2014	2015	2018
Patient no.	59	150	101
Design	Two arms comparing thrombolysis and no thrombolysis	Single arm	Four arms comparing four thrombolytic regimens
		No control group
PE severity	Intermediate-risk PE defined by RV/LV diameter ratio ≥ 1.0 on imaging	Massive or submassive PE	Intermediate-risk PE defined by RV/LV diameter ratio ≥ 0.9 on imaging
Thrombolysis regimen	Alteplase 1 mg/h per catheter for 5 hours then 0.5 mg/h per catheter for 10 hours (the maximum dose was 20 ± 1 mg for patients with bilateral device placement and 10 ± 0.5 mg for patients with unilateral device placement)	Alteplase 1 mg/h for 24 hours if unilateral device placement and for 12 hours if bilateral device placement	Either one of the following: Arm 1: alteplase 2 mg/h per catheter for 2 hours. Arm 2: alteplase 1 mg/h per catheter for 4 hours. Arm 3: alteplase 1 mg/h per catheter for 6 hours. Arm 4: alteplase 2 mg/h per catheter for 6 hours.
Primary endpoint	The difference in RV/LV diameter ratio from baseline to 24 hours	The change in RV/LV diameter ratio from baseline to 48 hours	The change in RV/LV diameter ratio from baseline to 48 hours

LV, left ventricle; PE, pulmonary embolism; RV, right ventricle.