麻豆传媒

People not requiring anticoagulation after transcatheter aortic valve replacement (TAVR or TAVI) had worse outcomes when given dual antiplatelet therapy (DAPT) instead of aspirin alone, the POPular TAVI trial found.

Aspirin without add-on clopidogrel (Plavix) was associated with lower bleeding risk in 12 months both in terms of any bleeding (15.1% vs 26.6% with clopidogrel, RR 0.57, 95% CI 0.42-0.77) and non-procedure-related bleeding including bleeds at the puncture site (15.1% vs 24.9%, RR 0.61, 95% CI 0.44-0.83), according to Jorn Brouwer, MD, of St. Antonius Hospital in Nieuwegein, the Netherlands.

Furthermore, aspirin alone was deemed superior over DAPT for the composite endpoint of cardiovascular death, non-procedure-related bleeding, stroke, or MI rates at 1 year (23.0% vs 31.1%, RR 0.74, 95% CI 0.57-0.95). As for the composite of cardiovascular death, ischemic stroke, or MI, aspirin alone met noninferiority but not superiority over DAPT (9.7% vs 9.9%, RR 0.98, 95% CI 0.62-1.55).

Brouwer presented the POPular TAVI cohort A data at the European Society of Cardiology (ESC) virtual meeting. The findings were simultaneously published online in the .

"The incidence of symptomatic clinical aortic-valve thrombosis, a process reflecting a high thrombotic burden, was low and similar in the two groups. In addition, the incidence of increased valve gradients during follow-up, a finding that suggests valve hemodynamic deterioration, was similar in the two groups," the researchers reported.

"Aspirin alone after TAVI reduces bleeding events significantly and does not increase the rate of thromboembolic events, so physicians can easily and safely reduce the rate of bleeding by omitting clopidogrel after TAVI," Brouwer concluded at an ESC press conference.

Cohort B results had already shown that patients with an indication for oral anticoagulation following TAVR had greater bleeding risk and no reduction in ischemic events on clopidogrel plus oral anticoagulants.

The present cohort A report is "much more interesting" since it describes the majority of TAVR patients who do not require anticoagulation, commented Danny Dvir, MD, of Shaare Zedek Medical Centre and Hebrew University of Jerusalem, and the University of Washington in Seattle.

Current guidelines recommend aspirin and clopidogrel for the first 3-6 months after the procedure -- a recommendation not backed by any randomized data, according to co-author Jurrien ten Berg, MD, PhD, also of St. Antonius Hospital, speaking during the ESC press conference.

POPular TAVI and other studies like make a strong case for dropping clopidogrel from the treatment of patients after TAVR, Dvir told 麻豆传媒.

"We should omit clopidogrel unless there is a different indication for it, such as recent coronary stenting," he wrote in an email. "PCI and TAVI procedures are very different and coronary stent thrombosis (prevented by [DAPT]) is not the same as valve thrombosis (prevented by anticoagulation and which is rarely indicated for biological valves implanted)."

POPular TAVI cohort A included 665 patients who were randomized to aspirin (80-100 mg daily) with or without clopidogrel (75 mg daily) for 3 months.

Participants were TAVR recipients without an indication for long-term anticoagulation (mean age 80; 48.7% women). However, 13.3% of aspirin and 9.6% of DAPT groups wound up receiving oral anticoagulation during the trial, mainly due to new-onset atrial fibrillation.

Clopidogrel adherence was 89.2% throughout the 3 months.

The reported between-group difference in bleeding was observed from minor to life-threatening bleeding types, but was most pronounced in major bleeding, according to the investigators.

It was noteworthy that most bleeds occurred in the first 30 days after TAVR, commented Robert Bonow, MD, of Northwestern University Feinberg School of Medicine in Chicago.

Brouwer's group acknowledged that the open-label trial was not powered for individual outcomes and did not mandate CT imaging for the detection of subclinical valve thrombosis.

Notably, the trial was not powered to assess whether there is ischemic protection from DAPT compared with aspirin alone. "But it is clear that even if that were the case, it would certainly come at the expense of a greater amount of bleeding in the periprocedural period," according to Ajay Kirtane, MD, of NewYork-Presbyterian Hospital/Columbia University Medical Center in New York City.

"This is a relatively small randomized trial, so whether these results will be practice-changing will depend on confirmation by additional studies, but it is reassuring to know that patients at higher risk for bleeding would appear to do well with low dose aspirin alone after TAVI," Bonow said.

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