Mechanical thrombectomy in intermediate-high-risk pulmonary embolism: STORM-PE trial results show improved 6-minute walk distance and functional recovery

Management of intermediate-high-risk pulmonary embolism (PE) remains one of the most debated areas in contemporary cardiovascular care. While anticoagulation remains foundational therapy, the question has long been whether earlier catheter-based reperfusion can meaningfully improve not just surrogate markers—but how patients actually feel and function.

The interim functional outcomes from the STORM-PE trial move the field closer to that answer.

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From RV/LV Ratios to Real-World Functional Recovery

The primary results of STORM-PE demonstrated that computer-assisted vacuum thrombectomy (CAVT) plus anticoagulation led to significantly greater reduction in RV/LV ratio at 48 hours compared with anticoagulation alone.

However, imaging metrics alone rarely drive bedside decisions.

What makes the 90-day data compelling is the shift toward patient-centered functional outcomes:

• 6-minute walk distance was significantly greater in the thrombectomy arm (479 m vs 368 m).
• NYHA Class I status was achieved in 97% vs 76%.
• A higher proportion returned to predicted baseline functional capacity.

Earlier right ventricular stabilization appears to translate into improved exercise tolerance, reduced dyspnea burden, and faster return to daily activity.

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Context: Evolving Evidence in Intermediate-Risk PE

Historically, guidelines recommended anticoagulation alone for most intermediate-risk PE patients, reserving advanced therapies for clinical deterioration.

The 2026 AHA/ACC/ACCP PE Guidelines reflect this evolving landscape. Mechanical thrombectomy carries:

• Class 2a recommendation in high-risk PE
• Class 2b recommendation in select intermediate-high-risk patients when advanced therapy is being considered

Recent randomized data are reshaping this conversation:

• PEERLESS Trial (2025) demonstrated that large-bore mechanical thrombectomy reduced clinical deterioration and ICU utilization compared with catheter-directed thrombolysis, with similar mortality and bleeding rates.
• Contemporary registry data from the PERT Consortium (JACC 2026) show rapid national adoption of mechanical thrombectomy, particularly in higher-acuity patients.

STORM-PE extends this trajectory by suggesting benefits beyond early hemodynamic improvement—toward functional recovery and quality of life.

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Why Functional Outcomes Matter

Up to 40–50% of PE survivors experience some degree of exercise limitation, persistent dyspnea, or features of post-PE syndrome, even after adequate anticoagulation.

If early thrombus removal:

• Reduces RV strain
• Preserves cardiopulmonary reserve
• Improves 6-minute walk performance
• Accelerates return to baseline activity

Then we may be shifting the goal from merely preventing mortality to improving long-term functional capacity and quality of life.

Mortality differences in intermediate-risk PE remain difficult to demonstrate. But for many patients, being able to walk normally, breathe comfortably, and resume daily activities is a highly meaningful endpoint.

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The Emerging Treatment Paradigm

We are witnessing a transition from purely anatomy- and biomarker-driven decision-making toward a model that incorporates:

• Hemodynamic stabilization
• Functional recovery
• Quality-of-life outcomes
• Multidisciplinary PERT-based evaluation

STORM-PE does not close the book on optimal management of intermediate-high-risk PE. But it adds important evidence that mechanical thrombectomy may improve how patients recover—not just how their scans look.

For cardiologists involved in acute PE response teams, these data are likely to influence discussions with referring physicians and patients in 2026 and beyond.

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References

1. STORM-PE Trial. Randomized controlled trial of mechanical thrombectomy plus anticoagulation vs anticoagulation alone in intermediate-high-risk PE. Circulation. 2026.

2. 2026 AHA/ACC/ACCP Guideline for the Evaluation and Management of Acute Pulmonary Embolism. Circulation. 2026.

3. PEERLESS Trial. Large-bore mechanical thrombectomy vs catheter-directed thrombolysis in intermediate-risk PE. Circulation. 2025.

4. PERT Consortium Registry (2016–2024). Trends in mechanical thrombectomy and catheter-directed therapies for acute PE. J Am Coll Cardiol. 2026.

5. Kahn SR et al. Functional and exercise limitations after pulmonary embolism (ELOPE Study). Chest. 2017.

Calcium Supplements in Patients With Cardiovascular Disease: Time for a More Cautious Approach?

Calcium supplementation has long been a cornerstone of osteoporosis prevention, particularly in older adults. However, emerging data raise important questions about its cardiovascular safety—especially in patients with established cardiovascular disease (CVD).

New Evidence in Patients With Established CVD

A large population-based cohort study from Hong Kong evaluated more than 230,000 adults aged 40 and older newly diagnosed with CVD. After propensity matching, calcium supplementation was associated with a higher risk of recurrent cardiovascular events, including myocardial infarction and stroke. The risk was more pronounced in:

• Patients taking calcium alone (without vitamin D)
• Men
• Those receiving higher daily doses (≥ 1,000 mg)

Importantly, patients taking calcium combined with vitamin D did not show an increased risk of recurrent events in this study, suggesting that co-supplementation may modify risk.

These findings extend prior concerns—largely derived from general populations—to patients with known CVD, a group already at high baseline risk.

Why Might Calcium Supplements Increase Risk?

Unlike dietary calcium, which is absorbed gradually, calcium supplements can produce transient increases in serum calcium levels. Repeated post-supplement “calcium spikes” may:

• Promote vascular calcification
• Increase arterial stiffness
• Enhance coagulability

Mendelian randomization studies and prior meta-analyses have also linked higher circulating calcium levels to increased risk of myocardial infarction, supporting a biologically plausible mechanism.

What About Vitamin D?

Vitamin D deficiency is associated observationally with adverse cardiovascular outcomes. However, randomized trials have generally failed to show cardiovascular benefit from vitamin D supplementation alone. Current evidence does not support vitamin D for primary cardiovascular prevention, although its role when combined with calcium remains debated.

Dietary vs Supplemental Calcium

One consistent theme across studies is the difference between dietary calcium and supplemental calcium. Dietary calcium intake has not been consistently associated with increased cardiovascular risk and may even be protective in some cohorts. In contrast, several meta-analyses of randomized trials have reported a modest increase in myocardial infarction risk with calcium supplements, particularly when not combined with vitamin D.

Guideline Perspective

The 2023 AHA/ACC guideline for chronic coronary disease recommends against the use of nonprescription supplements—including calcium—for reducing cardiovascular events. Calcium should not be used with the expectation of cardiovascular benefit.

Practical Takeaways for Clinicians

• In patients with established CVD, routine calcium supplementation should be reconsidered, particularly calcium-only therapy.
• When supplementation is necessary for bone health, consider:
  • Using the lowest dose needed to meet recommended intake
  • Preferring dietary calcium sources
  • Avoiding high-dose calcium-only regimens
• Management decisions should balance fracture risk against potential cardiovascular risk.

As with many areas in preventive cardiology, “more is not necessarily better.” For patients with cardiovascular disease, a thoughtful, individualized approach to calcium supplementation is warranted.

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References

1. Zhang X, et al. Association between calcium supplementation and recurrence of cardiovascular events in patients with cardiovascular disease. J Am Heart Assoc. 2026;15:e047455.
2. Bolland MJ, et al. Effect of calcium supplements on risk of myocardial infarction and cardiovascular events: meta-analysis. BMJ. 2010;341:c3691.
3. Chung M, et al. Vitamin D and calcium supplementation in prevention of cardiovascular events: systematic review. Ann Intern Med. 2010;152:315–323.
4. ACC/AHA Joint Committee on Clinical Practice Guidelines. 2023 Guideline for the Management of Patients With Chronic Coronary Disease. Circulation. 2023.

New Afib ablation technology may carry higher stroke risk, study finds

Patients treated with pulsed-field ablation (PFA) for atrial fibrillation (AF) had a stroke or TIA rate nearly five times higher than those receiving radiofrequency ablation (RFA), according to a new single-center observational study — though the overall risk remains low.

Stroke / TIA rate — PFA

0.47%

10 events among 2,144 patients

Stroke / TIA rate — RFA

0.10%

2 events among 2,077 patients

Researchers at Beth Israel Deaconess Medical Center in Boston analyzed more than 4,200 consecutive AF ablation procedures performed between 2022 and 2026. They presented their findings at the European Heart Rhythm Association (EHRA) Congress 2026 in Paris — where late-breaking science on ablation techniques for atrial fibrillation management was a major theme.

Pulsed-field ablation has rapidly grown in popularity over the past several years, largely because it uses irreversible electroporation — a non-thermal mechanism — and offers shorter procedure times with a reduced risk of serious complications like esophageal injury, phrenic nerve paralysis, and pulmonary vein stenosis. But the new data suggest a more nuanced picture may be emerging. For background on how pulmonary vein isolation (PVI) works as the cornerstone of AF ablation, the Cleveland Clinic provides a useful overview.

"As we continued to do more of the procedures, we started to understand that perhaps the safety profile was a little bit more nuanced," said lead researcher Dr. Enrico Ferro. His team noted observing a "shower of microbubbles" under intracardiac echocardiography (ICE) during PFA procedures — a finding that raised concern even when it didn't immediately translate into a neurological event.

Researchers were unable to pinpoint a single cause for the difference. Patient demographics, operator experience, and procedural workflow differences were all examined, but none fully explained the higher stroke signal. Possible mechanisms include microbubble formation, thrombus formation, and endothelial disruption during more extensive ablation of the posterior left atrial wall.

The study arrives amid a broader pattern of scrutiny. The NEMESIS-PFA registry previously reported higher rates of troponin leak, hemolysis, and renal dysfunction with PFA compared to RFA. And in early 2025, Johnson & Johnson temporarily paused U.S. rollout of its Varipulse PFA system after four neurovascular events were reported during an external evaluation — a rate of stroke and TIA around 3%, well above the expected 1% benchmark for this type of surgery.

Experts emphasize that perspective is important. The absolute event rates remain well below 0.5% in both groups — consistent with prior ablation studies. Still, commentators agree the signal warrants dedicated follow-up. "Every brain cell matters," said Dr. Wilber Su of Banner University Medical Center Phoenix, noting that silent cerebral emboli are an ongoing concern across PFA trials. A 2026 EHRA/HRS scientific statement on PFA likewise acknowledged the technology's distinct safety profile and the need for ongoing vigilance.

Next steps include a large US claims database study and a nationwide FDA-supported postmarket surveillance study focused on stroke risk associated with PFA. As Dr. Su put it: "The more experience we have with PFA, the more we can learn how to be safer with it."

References

1. Ferro EG. Comparative safety of PFA vs RFA for stroke events: insights from a high-volume US medical center. Presented at: EHRA 2026. April 12, 2026. Paris, France. Reported by TCTMD.
2. Lakkireddy D, et al. NEMESIS-PFA: investigating collateral tissue injury associated with pulsed field ablation. JACC Clin Electrophysiol. 2025.
3. Ha FJ, et al. Advent of pulsed field ablation for atrial fibrillation: state-of-the-art review. Rev Cardiovasc Med. 2025;26.
4. Kühne M, et al. Pulsed field ablation for the interventional treatment of atrial fibrillation: a scientific statement of EHRA, HRS, APHRS, LAHRS, and CHRS. EP Europace. 2026.
5. Sun M, et al. Pulsed field ablation for atrial fibrillation: clinical applications and research advances. Front Cardiovasc Med. 2025.
6. Johnson & Johnson MedTech. J&J pauses Varipulse PFA cases in US. MedTech Dive. January 8, 2025.
7. Cleveland Clinic. Pulmonary vein isolation (PVI) ablation. Cleveland Clinic Health Library.

New Evidence for Iliac Vein Stenting: The C-TRACT Trial

For years, clinicians have utilized iliac vein stenting to treat Postthrombotic Syndrome (PTS) based largely on clinical intuition. However, high-level evidence has been scarce—until now.

Data from the C-TRACT trial, recently published in the New England Journal of Medicine, provides the validation needed to refine our endovascular approach to obstructed iliac veins.

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Key Clinical Findings

The study randomized 225 patients with moderate-to-severe PTS to either endovascular therapy (stenting plus enhanced antithrombotics) or standard care. At 6 months, the interventional arm demonstrated:

• Symptom Reduction: Significantly improved scores on the Venous Clinical Severity Score (VCSS), showing a 2-point benefit over control (P = 0.001).

• Quality of Life: A robust 14.5-point increase in VEINES-QOL scores, indicating a meaningful impact on daily functionality.

• Device Performance: The benefits appear to be a class effect across approved venous stents, including Abre and Venovo.

The Trade-off: Bleeding Risk

The primary complication was a higher rate of bleeding events (11.6% vs. 3.6%; $P = 0.03$). These were predominantly nonmajor and likely linked to the intensified antithrombotic therapy required post-procedure, rather than the stenting procedure itself.

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Practice Implications

The C-TRACT results move the needle toward evidence-based intervention. However, success hinges on individualized care. Shared decision-making is essential to balance substantial quality-of-life gains against bleeding risks and the need for long-term surveillance.