Mechanical thrombectomy beats anticoagulation alone in STORM-PE
A long-awaited randomized trial has finally delivered key evidence supporting mechanical thrombectomy for acute pulmonary embolism (PE). Results from the STORM-PE trial, presented as a late-breaking clinical study at TCT 2025 in San Francisco, showed that mechanical thrombectomy combined with anticoagulation significantly outperformed anticoagulation alone in improving right heart function among patients with intermediate- to high-risk PE. The findings were also published in Circulation.[1]
"The field of interventional therapies for acute PE has really expanded rapidly in the last 10 years, but there has not been a randomized controlled trial evaluating any minimally invasive therapy since 2013, so many of us in the interventional space felt that there was a need to establish core data to move the field forward, and that's what STORM-PE was about," Robert Lookstein, MD, professor of radiology and surgery at the Icahn School of Medicine at Mount Sinai and president of the Society of Interventional Radiology (SIR), explained in an interview with Cardiovascular Business. "We found the addition of the thrombectomy procedure in a statistically significant way dramatically reduced the strain on the right heart as compared to anticoagulation alone."
STORM-PE trial addressed gap in knowledge
Lookstein noted that minimally invasive PE interventions have expanded rapidly in recent years, but evidence from randomized data has been missing. This trial addressed that gap by enrolling 100 patients with intermediate-high-risk PE—those hemodynamically stable, but showing significant right ventricular (RV) strain on CT or echocardiography imaging, and elevated biomarkers such as troponin. He said these are the patients that are usually on the brink of going downhill clinically.
Patients were randomized to standard anticoagulation therapy alone, or to anticoagulation plus mechanical thrombectomy using a computer-assisted vacuum thrombectomy (CAVT) system designed to selectively remove thrombus while minimizing blood loss. The system also can detect when the catheter is in contact with thrombus or the vessel wall.
Dramatic improvements will change PE patient care
"I believe this is a foundational trial that we've proven once and for all that the addition of a safe thrombectomy procedure can offload the failing right ventricle can stabilize the heart, take the strain off the patient, allow them to feel better," Lookstein said.
At 48 hours, a statistically significant number of patients in the thrombectomy arm had complete normalization of right heart function compared to the control group. The benefits were consistent across multiple measures of RV recovery.
Lookstein said the study results for the interventional arm were uniform, with good outcomes and a quick procedure length.
New thrombectomy system was safety and easy of use
In addition, the interventional arm from this trial demonstrated an excellent safety profile. There were no device- or procedure-related adverse events, and no access-site complications.
The CAVT system from Penumbra used in the study represents a significant technological leap from earlier mechanical aspiration devices. Unlike first-generation systems that relied on manual suction, the computer-assisted platform modulates vacuum power in real time, activating only when it detects thrombus contact. This reduces the risk of vessel trauma and blood loss.
“The technology can sense when the catheter is in clot versus in the vessel wall. I think it is a testament to how far the field has come," Lookstein said.
The system had only been U.S. Food and Drug Administration (FDA) cleared five months before trial enrollment began, meaning most operators were still getting comfortable with how it works. But it proved to be very intuitive and easy to use.
Foundational evidence for changing PE care
For hospitals hesitant to adopt interventional PE response team (PERT) programs due to a lack of definitive data, Lookstein believes STORM-PE changes the equation.
"I would argue it's a game changer in that it creates the level-one evidence first and foremost, that this therapy works, that it's safe and that it can improve the outcomes for patients that are at fairly high risk for cardiac decompensation."
Trial shows earlier PE physiological recovery than anticoagulation alone
Beyond hemodynamic and imaging results, the study also collected secondary endpoints on patient quality of life and functional recovery. These data were presented Nov. 3 at VIVA 2025 conference in Las Vegas.
The secondary outcomes included early physiological recovery with a significantly lower heart rate for the thrombectomy arm (80 bpm vs. 86.4 bpm). There were also fewer cases of tachycardia with heart rates of more than 100 beats per minute (2.2% vs. 20%).
Thrombectomy patients also had reduced supplemental oxygen requirements (0.5 L/min vs 1.4 L/min), and a lower NEWS2 risk of clinical deterioration (1.8 vs. 2.7) at 48 hours. Also, these patients were 2.2 times more likelihood of progress towards recovery of functional status.
These patients also walked significantly further during the 90-day, six-minute walk test (472 meters vs. 376 meters). Additionally, CAVT patients nearly normalized by 90-days, walking 94% of their predicted walk distance, versus 75% in the anticoagulation only arm.
Dave Fornell has covered healthcare for more than 17 years, with a focus in cardiology and radiology. Fornell is a 5-time winner of a Jesse H. Neal Award, the most prestigious editorial honors in the field of specialized journalism. The wins included best technical content, best use of social media and best COVID-19 coverage. Fornell was also a three-time Neal finalist for best range of work by a single author. He produces more than 100 editorial videos each year, most of them interviews with key opinion leaders in medicine. He also writes technical articles, covers key trends, conducts video hospital site visits, and is very involved with social media. E-mail: [email protected]