Does the type of rhythm control matter?

The risk of dementia increases in patients atrial fibrillation (AF), but some evidence suggests the risk may be mitigated by therapies that restore sinus rhythm. But a new cohort study suggests that the magnitude of the treatment effect may depend on the rhythm control strategy. He hinted that AF catheter ablation may be more effective than pharmacological rhythm control alone in reducing the risk of dementia.

The matched case study of over 38,000 adults with AF found a 41% reduction (P

The observational study comprising 20 years of data has great limitations and cannot say with certainty whether catheter ablation is better than DAA alone in reducing the risk of dementia in AF. But that and other evidence supports the idea, which has yet to be explored on a random basis.

In a secondary outcome, the analysis showed a similar reduction in the risk of dementia due to catheter ablation, compared to DAA, in women and men of 40% and 45%, respectively (P | Medscape Cardiology. “I think that’s another reason to try to be more generous in offering ablation to women.”

The management of AF has certainly evolved significantly from 2000 to 2021, the period covered by the study. But a sensitivity analysis based on data from 2010 to 2021 showed “no significant difference” in the results, said Zeitler, who is expected to present the results on April 30 at the Heart Rhythm Society 2022 Scientific Sessions, conducted virtually and live in San Francisco.

Zeitler acknowledged that the observational study, even with its propensity-matched ablation and DAA cohorts, can only indicate a preference for ablation over DAA to reduce the risk of dementia associated with AF. “We know there is unmeasured and unresolved confusion between these two groups, so we really see this as hypothesis-generating.”

It was “a well-done analysis,” and the conclusion that dementia risk was lower with catheter ablation is “absolutely correct,” but only to the extent that the study and its limitations allow, said agreed David Conen, MD, MPH, McMaster University, Hamilton, Ontario, Canada, who is not a co-author.

“Even with propensity matching you can get rid of some kinds of confusion, but you can never get rid of all the selection bias issues.” That, he said in an interview, takes randomized trials.

Conen, who studies cognitive decline in AF as the principal investigator of the SWISS-AF trial, pointed to a secondary finding from the analysis as evidence of such confusion. He said the nearly 50% drop in the ablation group (P

The finding “strongly suggests that these people were healthier and that there is some sort of selection bias. caress, myocardial infarctionthrombosis and cancer because they were probably a little bit healthier than the others,” Conen said. The ablation and DAA groups “were two very different populations to begin with.”

The analysis was based on data from U.S. insurance and Medicare claims of patients with AF who underwent catheter ablation after at least one trial of DAA or who filled prescriptions for at least two different antiarrhythmic agents in the year following the diagnosis of AF. Patients with a history of dementia, catheter or surgical removal of AF, or valve surgery were excluded.

The ablation and DAA-only groups each included 19,066 patients after propensity matching, and the groups were balanced with respect to age, gender, insurance type, CHA2DS2-VASc scores and use of renin-angiotensin system inhibitors, oral anticoagulants and antiplatelet drugs.

The overall risk of dementia was 1.9% for the ablation group and 3.3% for patients on DAAs only (relative risk [HR], 0.59; 95% CI, 0.52 – 0.67). The corresponding RRs by sex were 0.55 (95% CI, 0.46, 0.66) for men and 0.60 (95% CI, 0.50, 0.72) for women .

The concurrent risk of death was also significantly decreased in the ablation group (HR, 0.51; 95% CI, 0.46, 0.55).

Zeitler pointed to a randomized trial now in the early stages called Neurocognition and Greater Sinus Rhythm Maintenance in Atrial Fibrillation, or NOGGIN-AFwhich will explore the relationships between rhythm control therapy and dementia in patients with AF, whether catheter ablation or DAA can mitigate this risk, and whether either strategy works better than either another, among other objectives.

“I’m optimistic,” she said, “and I think this will add to the growing motivations to achieve faster and broader patient ablation.”

The analysis was funded by Biosense-Webster. Zeitler leaks advice for Biosense-Webster and Arena Pharmaceuticals (now Pfizer); Medtronic speaking fees; and receive research support from Boston Scientific, Sanofi and Biosense-Webster. Conen has previously said he received speaker fees from Servier Canada.

2022 Heart Rhythm Society (HRS) Scientific Sessions. Abstract CA-532. To be presented on April 30, 2022.

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