乌鸦传媒

SAN FRANCISCO -- Left atrial appendage occlusion (LAAO) at the time of transcatheter aortic valve replacement (TAVR) appeared as safe as TAVR alone, the WATCH-TAVR trial showed.

For patients with severe aortic stenosis and atrial fibrillation (AF or Afib), the combined approach met non-inferiority to TAVR plus medical therapy for the primary composite endpoint of all-cause mortality, stroke, and major bleeding at 2 years (22.7 vs 27.3 events per 100 patient-years, P<0.001 for non-inferiority).

While the hazard ratio for that combined endpoint favored TAVR plus LAAO (HR 0.86, 95% CI 0.60-1.22), it was not significantly superior (P=0.40), reported Samir Kapadia, MD, of the Cleveland Clinic, at the Transcatheter Cardiovascular Therapeutics (TCT) meeting and online in .

Some 20% of TAVR patients subsequently get a Watchman device for LAA closure, Kapadia estimated at a TCT press conference. "Actually making the procedure at the same time ... is better for the patient rather than doing sequential procedures," Kapadia said, referencing convenience for the patient and potentially reduced cost and risk from repeated interventions.

Indeed, surgical LAA closure is routine for Afib patients undergoing cardiac surgery, noted TCT press conference panelist Kendra Grubb, MD, of the Emory Structural Heart and Valve Center in Atlanta. Such an approach in the reduced risk of stroke or systemic embolism by 2.2 percentage points over 3 years, with a relative 33% ischemic stroke reduction.

"WATCH-TAVR not only replicates this surgical learning but is the first study to investigate concomitant percutaneous procedures treating two separate conditions in structural heart disease patients," Kapadia's group wrote.

TCT session study discussant Megan Coylewright, MD, MPH, of the Erlanger Health System in Chattanooga, Tennessee, said she questioned 20 of her TAVR patients with Afib and high bleeding risk about whether they would want the procedures combined or staged. "They looked at me like I lost my mind. 'What do you mean? Why would I want it staged?'" she said. "I asked my colleagues if they want to take more beds for staged procedures. It seems like a no-brainer."

She questioned whether, with so much data on both procedures, there was a need for such a trial at all and future combinations of structural heart procedures could just rely on registry data.

"I hope after today, people will say 'Gosh, that makes a lot of sense,'" Coylewright told 乌鸦传媒.

However, the researchers cautioned: "The increased complexity and risks of the combined procedure should be considered when concomitant LAAO is viewed as an alternative to medical therapy for patients with AF undergoing TAVR."

The combined procedure group had a higher rate of thromboembolism, mainly from more frequent venous thrombosis. Arterial or venous thrombosis or embolism occurred in 9.0% of the combined procedure group compared with 1.7% of the TAVR-alone group, a more than five-fold higher risk (95% CI 1.47-17.26).

Pericardial effusion occurred in 2.4% of combined procedures compared to 0.5% in TAVR alone.

Need for pericardiocentesis is a known complication of the Watchman 2.5 LAA closure device used in the study, although the newer-generation "demonstrated a marked reduction in the risk of pericardial effusion in the NCDR [National Cardiovascular Data Registry] database," Kapadia's group noted.

Another aspect of adding LAAO is that it is often performed under general anesthesia and transesophageal echocardiography, whereas TAVR usually just takes conscious sedation. However, the same delayed-phase acquisition CT could be used to plan both procedures "and make preoperative evaluation of the combined procedure seamless and efficient," Kapadia's group suggested.

Trial Details

Their trial included 349 patients getting TAVR with any commercially available device for symptomatic, severe aortic stenosis at 34 U.S. centers from December 2017 to November 2020.

Participants were randomized to TAVR with concomitant LAAO with the Watchman 2.5 device or TAVR with anticoagulation according to treating physician preference. The combined procedure group got anticoagulation for 45 days followed by dual antiplatelet therapy (DAPT) until 6 months.

Participants' mean age was 81, with an average CHA₂DS₂-VASc score of 4.9 and HAS-BLED score of 3.0. Antithrombotic therapy use at baseline included anticoagulation and antiplatelet therapy for most patients (85.4% and 71.3%, respectively, for the two classes individually and 59.3% on both).

LAAO added 38 minutes to the TAVR procedure on average, with an additional 49 mL of contrast volume, which Kapadia's group called "acceptable."

In-hospital mortality was low (0.6%) in both groups, with similar hospital length of stay and acute kidney injury rates.

At 24 months follow-up, the combined procedure group was more likely to be on any antiplatelet therapy (82.5% vs 50.8%) but less likely to be on any anticoagulant (13.9% vs 66.7%). Patients with severe mitral stenosis or other indications for anticoagulation were excluded.

The combined procedure group had numerically more major and life-threatening bleeding during the initial 6-month period of oral anticoagulation and DAPT (HR 1.35, 95% CI 0.76-2.39) then numerically lower rates than the TAVR-alone group between 6 months and 2 years (HR 0.63, 95% CI 0.25-1.57).

"The prescribed adjunctive pharmacotherapy was based on the approved WATCHMAN 2.5 device label at that time which has since been updated to allow for DOACs [direct oral anticoagulants] or DAPT with the WATCHMAN FLX device," the researchers noted. They pointed to the higher bleeding risk seen with DAPT than with anticoagulation alone in data from the NCDR LAAO registry.

"It is likely that with insights from and other studies investigating less intense anticoagulation/antiplatelet regimens post WATCHMAN implant, bleeding will be reduced during the initial 6 months after device implantation," Kapadia's group suggested.

Money Matters

The recently reported ADALA trial, the first randomized trial of antithrombotic therapy after LAAO, showed that low-dose apixaban (Eliquis) had substantially lower risk of thromboembolic events and device-related thrombosis at 3 months than DAPT with aspirin and clopidogrel, and also numerically less VARC-3 major bleeding and significantly fewer bleeds when combining major and minor events.

Perhaps a bigger issue for many centers is financial, noted TCT press conference panelist Pinak B. Shah, MD, of the Brigham and Women's Hospital Cardiac Catheterization Lab in Boston.

"I take away from this [trial] that this is a safe approach, if you decide to have that conversation with the patients," he said. However, he added: "We get [diagnosis-related group], at least in the United States, for one procedure. I think a lot of programs in the country have a hard time just keeping TAVR programs afloat. And now we're thinking about adding a Watchman on top of that, what are the financial implications for individual institutions?"

Kapadia said that talks have started with CMS about getting a combined code for reimbursement. "There is some hope."

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