ѻý

AFib Ablation Bests Standard Therapy in HF Patients

<ѻý class="mpt-content-deck">— Benefits seen in younger patients with ICDs in CASTLE-AF trial
MedpageToday

BARCELONA -- Catheter ablation for atrial fibrillation (Afib) was better than drugs at protecting patients with heart failure from death and hospitalization, according to results of the CASTLE-AF trial presented here.

The trial randomized Afib patients with left ventricular (LV) ejection fractions at 35% or below to ablation (n=179) or conventional therapy (n=184), reported Nassir Marrouche, MD, of the University of Utah at Salt Lake City, and colleagues at the (ESC) meeting.

Action Points

  • Note that this study was published as an abstract and presented at a conference. These data and conclusions should be considered to be preliminary until published in a peer-reviewed journal.

Combined mortality and worsening heart failure admissions rates favored the ablation group after 5 years (28.5% versus 44.6% for controls, HR 0.62, 95% CI 0.43-0.87). A significant difference between therapies was preserved when all-cause mortality (13.4% versus 25%, HR 0.53, 95% CI 0.32-0.86) and heart failure hospitalization (20.7% versus 35.9%, HR 0.56, 95% CI 0.37-0.83) were analyzed individually.

Marrouche's group included patients mostly intolerant to or unwilling to take anti-arrhythmic drugs, leaving just under one-third of their group on amiodarone (Cordarone) and the like. Both arms of the trial were largely on ACE inhibitors, beta blockers, diuretics, and/or anticoagulation on baseline.

Importantly, all participants also had an implantable cardioverter-defibrillator (ICD) or cardiac resynchronization therapy defibrillator (CRT-D) already implanted. In a , Marrouche acknowledged that it was a limitation to CASTLE-AF that patients had to have these devices.

Another caveat: a run-in period with patients excluded before the final cohort was randomized. This can introduce bias, according to discussant Carina Blomström-Lundqvist, MD, PhD, of Uppsala University in Sweden, at the late-breaking trial ESC session.

She nevertheless called CASTLE-AF "highly relevant."

"It's time to offer Afib ablation procedures at an earlier stage in heart failure patients with Afib. But patient selection is important; that should reflect the populations included in this trial," Blomström-Lundqvist said. She described them as "healthier" patients -- being relatively young at a median age 64, over half in NYHA Class II, and a less than one-third having long-standing persistent Afib -- who are likely to tolerate catheter ablation.

The ablation group in the trial underwent with additional lesions made at the operator's discretion.

Effects of the procedure seemed long-lasting: Afib burden as captured by implanted device memory fell from 50% of the time to around 30% at 3 months post-ablation (though Afib burden crept up slightly again by the 5-year mark); and LV ejection fraction went up 8 absolute percentage points from baseline after ablation (versus 0 for the conventional therapy group, P=0.005).

On subgroup analysis, LV ejection fraction interacted with treatment type, giving patients with very low ejection fractions (under 25%) much better outcomes with ablation over conventional therapy (P=0.01).

"A significant number of patients undergoing the ablation treatment were still in normal rhythm at the end of the study," the investigators added. Blomström-Lundqvist said this was a notable surprise to her.

  • author['full_name']

    Nicole Lou is a reporter for ѻý, where she covers cardiology news and other developments in medicine.

Disclosures

Marrouche and co-authors disclosed relevant relationships with Abbott, Biotronik, Wavelet Health, Cardiac Design, Medtronic, Preventice, Vytronus, Biosense Webster, Marrek, Boston Scientific, GE Healthcare, and Siemens.

Blomström-Lundqvist disclosed no relevant relationships with industry.

Primary Source

European Society of Cardiology

Marrouche NF and Brachmann J "Catheter ablation versus standard conventional treatment in patients with left ventricular dysfunction and atrial fibrillation" ESC 2017.