Late-breaking clinical trials presented at ACC.26 focusing on structural interventions included the PROTECT H2H trial comparing two embolic protection devices (EPDs) in patients undergoing transcatheter aortic valve implantation (TAVI), the PRO-TAVI trial comparing a strategy of routine PCI with a deferred approach in patients undergoing TAVI, and the SURViV trial comparing redo surgery against a transcatheter valve-in-valve (ViV) procedure for mitral bioprosthetic dysfunction.

PROTECT H2H: Emboliner Protection Device Provides Acceptable Alternative to Sentinel in TAVI

Despite an incidence of only 2-4% surrounding TAVI, periprocedural stroke remains one of the most feared complications.¹ However, multiple randomized trials have failed to demonstrate a reduction in clinical stroke with currently available cerebral EPDs,^2-4 raising questions about their clinical utility despite strong mechanistic rationale.

In the PROTECT H2H late-breaking trial, the investigators compared the current standard dual-filter EPD (Sentinel, Boston Scientific), which lacks posterior circulation coverage, with a next-generation device (Emboliner, Emboline) designed to provide full aortic arch protection via contralateral femoral access while maintaining procedural functionality through an integrated port.

In this prospective, randomized, multicenter, open-label study, 522 patients undergoing TAVI were assigned 1:1 to either device. The primary endpoint was a noninferiority comparison of 30-day major adverse cardiovascular and cerebrovascular events (MACCE), defined as death, stroke (Valve Academic Research Consortium-2), or stage 3 acute kidney injury.

Among 485 patients in the modified intention-to-treat cohort, baseline characteristics and procedural variables were well balanced. At 30 days, Emboliner met criteria for noninferiority, with MACCE rates of 4.5% versus 5.0% and identical stroke rates of approximately 2% in both groups. Importantly, Emboliner demonstrated higher technical success (96% vs. 87%, p=0.0005) and substantially greater debris capture, including thrombus, valve tissue, and calcific material.

The PROTECT H2H trial demonstrates an acceptable EPD alternative and continues to demonstrate a disconnect between mechanistic protection/efficacy and clinical outcomes. Despite markedly increased debris capture and improved device performance, no reduction in clinical stroke was observed. This reinforces the possibility that either current stroke endpoints are insufficiently sensitive, embolic phenomena are not the sole driver of neurologic injury, or that substantially larger trials – or alternative endpoints such as diffusion-weighted MRI—are required to demonstrate benefit.

Thus, although Emboliner represents a technically successful evolution in EPD design, its clinical advantage over existing devices – and over no protection at all – remains unproven.

PRO-TAVI: Deferring PCI Until After TAVI in Patients With CAD Is Safe, Reduces Bleeding

Patients undergoing TAVI frequently have concomitant coronary artery disease (CAD), yet the role and timing of PCI in this population remain uncertain.⁵ In PRO-TAVI,⁶ a contemporary, investigator-initiated, randomized controlled trial, patients with significant coronary stenoses (≥70% or physiologically significant intermediate lesions) were assigned to PCI prior to TAVI versus a strategy of deferred revascularization.

A total of 466 patients were randomized across 12 Dutch centers, with PCI performed within two weeks of assignment. Patients had to have evidence of significant stenosis (70-99%) in a vessel >2.5 mm, or have an intermediate lesion deemed ischemic via resting or hyperemic intracoronary physiology and assessed by a core laboratory. Antithrombotic therapy reflected standard practice for patients with atrial fibrillation, and dual antiplatelet therapy in the PCI arm and single antiplatelet therapy in the TAVI-only group. The primary endpoint was a composite of all-cause mortality, myocardial infarction, stroke, or major bleeding at one year.

The groups were well balanced with a median age of 81 years, 36% women, and Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM) risk scores of 3.1%. Interestingly, 36% of patients in the deferral group had angina compared with 44% in the PCI group. Technical success approached 99% for both PCI and TAVI groups, with a <1% rate of acute kidney injury.

At one year, the primary endpoint occurred in 24% of the deferred group and 26% of the PCI group, meeting criteria for noninferiority without evidence of superiority. Importantly, there were no significant differences in death, myocardial infarction, or stroke. However, major bleeding was significantly lower in the deferred group (6% vs. 15%; hazard ratio [HR], 0.39; 95% CI, 0.21–0.73), highlighting a clear safety signal against routine pre-TAVI PCI. Notably, only 11% of patients in the deferred arm required PCI following TAVI.

The key teaching point is that routine PCI prior to TAVI in patients with stable CAD does not improve ischemic outcomes and may expose patients to unnecessary bleeding risk. These findings support a more selective, symptom- or physiology-guided approach to revascularization. Importantly, the applicability of this strategy to patients with high-risk coronary anatomy, such as left main or proximal left anterior descending disease, remains uncertain and warrants further investigation.

SURViV: Positive Early Returns of Transcatheter Mitral ViV Procedure For Failed Surgical Bioprostheses

Replacement of diseased mitral valves with bioprosthetic devices remains common worldwide, particularly in regions with endemic rheumatic heart disease. However, degeneration of these valves presents a difficult clinical problem, as redo surgical mitral valve replacement carries substantial perioperative risk, with reported 30-day mortality rates approaching 20% in some series.⁷ Less invasive alternatives such as transcatheter mitral ViV implantation have emerged, but randomized data have been lacking.⁸

The SURViV trial is a prospective, investigator-initiated randomized study conducted across seven centers in Brazil comparing redo surgical mitral valve replacement with transcatheter mitral ViV in patients with symptomatic bioprosthetic valve dysfunction. Eligible patients underwent transesophageal echocardiography and cardiac CT and were randomized 1:1 if suitable for both strategies. Key exclusions included severe left ventricular (LV) dysfunction (<20%), predicted neo–LV outflow tract obstruction (neoLVOT <170 mm²), and active thrombus or infection.

A total of 150 patients were randomized, with well-balanced baseline characteristics (mean age, 58 years; 72% women). At one year, the primary endpoint of all-cause death or disabling stroke occurred significantly more often in the redo surgery group compared with the ViV group (20.8% vs. 5.3%; HR, 0.23; p=0.005). This difference was largely driven by early postoperative mortality in the surgical cohort.

Transcatheter ViV was also associated with fewer early complications, including lower rates of major bleeding and renal dysfunction, and shorter hospital stays. Whereas all-cause rehospitalization rates were similar between groups, cardiac rehospitalizations were lower in the ViV cohort (2.8% vs. 16.0%). These findings are consistent with prior observational and meta-analytic data demonstrating lower periprocedural morbidity with transcatheter approaches.^8,9

Both strategies resulted in meaningful improvements in symptoms and quality of life. Although some echocardiographic parameters differed between groups, these did not clearly translate into clinically meaningful advantages at one year.

The SURViV trial provides the first randomized evidence supporting transcatheter mitral ViV as a preferred strategy in appropriately selected patients with failed bioprosthetic valves, primarily driven by a substantial reduction in early mortality and morbidity. Longer-term follow-up will be essential to determine durability and optimal lifetime management strategies.

References

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2. Kapadia SR, Makkar R, Leon M, et al. Cerebral embolic protection during transcatheter aortic-valve replacement. N Engl J Med. 2022;387(14):1253-1263. doi:10.1056/NEJMoa2204961
3. Lansky AJ, Makkar R, Nazif T, et al. A randomized evaluation of the TriGuard™ HDH cerebral embolic protection device to Reduce the Impact of Cerebral Embolic LEsions after TransCatheter Aortic Valve ImplanTation: the REFLECT I trial. Eur Heart J. 2021;42(27):2670-2679. doi:10.1093/eurheartj/ehab213
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6. Delewi R, Aarts HM, Broeze GM, et al. Deferral of percutaneous coronary intervention in patients undergoing transcatheter aortic valve implantation (PRO-TAVI): an investigator-initiated, multicentre, open-label, non-inferiority, randomised controlled trial. Lancet. 2026;407(10537):1429-1438. doi:10.1016/S0140-6736(26)00308-97.
7. Zubarevich A, Szczechowicz M, Zhigalov K, et al. Surgical redo mitral valve replacement in high-risk patients: the real-world experience. J Card Surg. 2021;36(9):3195-3204. doi:10.1111/jocs.15787
8. Ismayl M, Abbasi MA, Mostafa MR, et al. Meta-analysis comparing valve-in-valve transcatheter mitral valve replacement versus redo surgical mitral valve replacement in degenerated bioprosthetic mitral valve. Am J Cardiol. 2023;189:98-107. doi:10.1016/j.amjcard.2022.11.043
9. Zahid S, Ullah W, Hashem AM, et al. Transcatheter valve-in-valve implantation versus redo surgical mitral valve replacement in patients with failed mitral bioprostheses. EuroIntervention. 2022;18(10):824-835. doi:10.4244/EIJ-D-22-00437