Representation of obesity in contemporary atrial fibrillation ablation randomized controlled trials.

BACKGROUND: The prevalence and impact of obesity on outcomes of atrial fibrillation (AF) ablation randomized controlled trials (RCTs) have not been well studied. OBJECTIVE: To examine the proportion of participants with obesity enrolled in RCTs of AF ablation and outcomes of ablation when subgroup analysis of participants with obesity were available. METHODS: We systematically searched PubMed and EMBASE for AF ablation RCTs published between January 1, 2015 to May 31, 2022. When body mass index (BMI) data were available, normal distribution was assumed and a z score was used to estimate the proportion of obesity. Results categorized by BMI or body weight status were reviewed. Authors were contacted for additional information. RESULTS: Of 148 eligible RCTs with 30174 participants, 144 (97.30%) RCTs did not report the proportion of participants with obesity, while published information regarding BMI was available in 63.51%. Three trials excluded patients based on BMI. Using reported BMI, we estimated the proportion of participants with obesity varied greatly across these trials, ranging from 5.82%-71.9% (median 38.02%, interquartile 29.64%, 49.10%). Patients with obesity were represented in a greater proportion among trials conducted in North America (50.23%) and Asia (44.72%), compared to others (32.16%), p < .001. Subgroup analysis or analysis adjusting for BMI was reported in only 13 (8.78%) RCTs; four (30.77%) of these suggested that BMI or body weight might negatively affect primary outcomes. CONCLUSION: Obesity is a common comorbidity among AF patients. However, most AF ablation RCTs underreported the proportion of participants with obesity and its impact on the primary outcomes.

Predictive value of interatrial block on electrocardiogram among obese patients undergoing atrial fibrillation ablation.

BACKGROUND: Determine a predictive value of interatrial block (IAB) on atrial fibrillation (AF) ablation outcomes in obese patients. METHODS: Medical records were retrospectively reviewed for 205 consecutive patients with body mass indices (BMI) ≥ 30 kg/m2 who underwent initial AF ablation. Evidence of partial IAB defined as P-wave duration (PWD) ≥ 120 ms and advanced IAB with PWD ≥ 120 ms and biphasic or negative P-wave in inferior leads was examined from sinus electrocardiograms (ECGs) within 1-year pre-ablation. The primary outcome was recurrent atrial arrhythmia after 3-month blanking period post-ablation. RESULTS: The mean BMI was 36.9 ± 5.7 kg/m2. Partial IAB and advanced IAB were observed in 155 (75.61%) and 42 (20.49%) patients, respectively. During the median follow-up of 1.35 (interquartile range 0.74, 2.74) years, 115 (56.1%) patients had recurrent atrial arrhythmias. In multivariable analysis adjusting for age, gender, persistent AF, use of antiarrhythmic drugs (AADs), left atrial volume index (LAVI), partial IAB, and advanced IAB were independent predictors of recurrent arrhythmia with hazard ratio (HR) of 2.80 (95% confidence interval [CI] 1.47-6.05; p = 0.001) and HR 1.79 (95% CI 1.11-2.82; p = 0.017), respectively. The results were similar in a subgroup analysis of patients who had no severe left atrial enlargement and a subgroup analysis of patients who were not on AADs. CONCLUSIONS: IAB is highly prevalent in patients with obesity and AF. Partial IAB, defined as PWD ≥ 120 ms, and advanced IAB with evidence of biphasic P-wave in inferior leads were independently associated with increased risk of recurrent arrhythmia after AF ablation. Its predictive value is independent of other traditional risk factors, LAVI, or use of AADs.

Prevalence and Impact of Poorly Controlled Modifiable Risk Factors Among Patients Who Underwent Atrial Fibrillation Ablation.

Managing atrial fibrillation (AF) risk factors (RFs) improves ablation outcomes in obese patients. However, real-world data, including nonobese patients, are limited. This study examined the modifiable RFs of consecutive patients who underwent AF ablation at a tertiary care hospital from 2012 to 2019. The prespecified RFs included body mass index (BMI) ≥30 kg/m2, >5% fluctuation in BMI, obstructive sleep apnea with continuous positive airway pressure noncompliance, uncontrolled hypertension, uncontrolled diabetes, uncontrolled hyperlipidemia, tobacco use, alcohol use higher than the standard recommendation, and a diagnosis-to-ablation time (DAT) >1.5 years. The primary outcome was a composite of arrhythmia recurrence, cardiovascular admissions, and cardiovascular death. In this study, a high prevalence of preablation modifiable RFs was observed. More than 50% of the 724 study patients had uncontrolled hyperlipidemia, a BMI ≥30 mg/m2, a fluctuating BMI >5%, or a delayed DAT. During a median follow-up of 2.6 (interquartile range 1.4 to 4.6) years, 467 patients (64.5%) met the primary outcome. Independent RFs were a fluctuation in BMI >5% (hazard ratio [HR] 1.31, p = 0.008), diabetes with A1c ≥6.5% (HR 1.50, p = 0.014), and uncontrolled hyperlipidemia (HR 1.30, p = 0.005). A total of 264 patients (36.46%) had at least 2 of these predictive RFs, which was associated with a higher incidence of the primary outcome. Delayed DAT over 1.5 years did not alter the ablation outcome. In conclusion, substantial portions of patients who underwent AF ablation have potentially modifiable RFs that were not well controlled. Fluctuating BMI, diabetes with hemoglobin A1c ≥6.5%, and uncontrolled hyperlipidemia portend an increased risk of recurrent arrhythmia, cardiovascular hospitalizations, and mortality after ablation.