Randomized trial of low-dose, ultrasound-assisted thrombolysis or heparin for pulmonary embolism
Summary
In 210 adults with intermediate-high-risk PE, this Danish multicenter RCT compared ultrasound-assisted catheter alteplase, IV alteplase, and heparin. Both thrombolysis arms used 20 mg over 6 hours. Thrombolysis improved CT clot-score reduction versus heparin by 3.6 points (95% CI 2.2–5.0); ultrasound assistance offered no advantage over IV delivery (difference −0.1, 95% CI −1.9 to 1.7).
Why it matters
Clot clearance alone does not establish a reason to escalate a stable patient to thrombolysis or select catheter treatment.
Study at a glance
- Design
- Randomized trial
- Population
- Adults with acute intermediate-high-risk PE presenting to EDs in two Danish regions.
- Sample size
- 210
- Intervention
- Alteplase 20 mg over 6 hours, by ultrasound-assisted catheter or IV infusion.
- Comparator
- Heparin alone; catheter versus IV thrombolysis also compared.
- Primary endpoint
- Change in refined Modified Miller CT clot score at 48–96 hours.
Main findings
- Ultrasound assistance did not improve the primary imaging result over IV alteplase.
- No statistically established clinical-outcome advantage was reported in the abstract.
Limitations
Small trial with an imaging endpoint; not powered to establish mortality benefit. The abstract reports numerically more bleeding with thrombolysis but supplies no event counts.
Read the primary source
Full text: Abstract available; full text paywalled.
Original sourceDOI: 10.1093/cvr/cvag038
PMID: 41610160
Material reviewed: abstract.
Source retrieved Oct 30, 2026. Abstract reviewed; full text unavailable. Primary publisher verifies January 30; February 16 is typesetting, not first online. Abstract results and conclusion differ in their wording about death/bleeding; exact safety counts require full-text review. No separate correction/retraction found by DOI search. Later HI-PEITHO (NEJM DOI 10.1056/NEJMoa2516567) found a clinical-composite benefit for catheter therapy versus anticoagulation in a differently selected population; it did not compare catheter with IV low-dose thrombolysis. Do not generalize STRATIFY to all catheter reperfusion strategies.
Corrections & review history
No corrections recorded. Human review: not yet human-reviewed.