Body mass index as a determinant of scar formation post‐AF ablation: Insights from DECAAF II
Ghassan Bidaoui, Eli Tsakiris, Hadi Younes, Han Feng, Ala Assaf, Nour Chouman, Mayana Bsoul, Francisco Tirado Polo, Yishi Jia, Yingshou Liu, Chanho Lim, Nadia Chamoun, Mario Mekhael, Charbel Noujaim, Amitabh C. Pandey, Swati Rao, Omar Kreidieh, Nassir F. Marrouche, Eoin DonnellanAbstract
Introduction
Obesity is implicated in adverse atrial remodeling and worse outcomes in patients with atrial fibrillation. The objective of this study is to assess the effect of body mass index (BMI) on ablation‐induced scar formation on late gadolinium enhancement cardiac magnetic resonance imaging (LGE‐CMR).
Methods
We conducted an analysis of DECAAF II participants who underwent LGE‐CMR scans to measure scar formation 3 months after catheter ablation. Ablation parameters and lesion delivery were not dependent on BMI. The effect of BMI on ablation success was explored.
Results
Our analyses included 811 patients. Comorbidities were more prevalent in obese patients. Baseline left atrial volume was higher in obese individuals, 118, 126, 135, 140, and 143 mm3 for normal weight, overweight, obese grade 1, 2, and 3, respectively (p < .001). BMI was associated with scar formation (R = −0.135, p < .001), with patients with Class 3 obesity having the lowest percentage of ablation‐induced scar, 11.1%, 10.3%, 9.5%, 8.8%, 6.8% by ascending BMI group. There was an inverse correlation between BMI and the amount of fibrosis covered by ablation scar, 24%, 23%, 21%, and 18% by ascending BMI group (p = .001). For the fibrosis‐guided ablation group, BMI was associated with residual fibrosis (R = 0.056, p = .005).
Conclusion
Obese patients have lower ablation scar formation, covered fibrosis, and more residual fibrosis postablation compared to nonobese patients, regardless of ablation parameters including impedance drop.