Clinical and cardiac structural predictors of atrial fibrillation persistence

Efficacy and safety of catheter ablation for atrial fibrillation in elderly patients: a systematic review and meta-analysis

BACKGROUND

Catheter ablation (CA) is a well-established therapy for patients with atrial fibrillation (AF); however, there is paucity of data for elderly patients. We aimed to assess long-term efficacy and safety of CA for elderly patients with AF.

METHODS

Medline, BVS, Cochrane, and Embase were searched through April 2023 to investigate comparative outcomes between elderly patients > 75 or 80 years, as per-study cutoff, and individuals ≤ 75/80 years, undergoing CA. Primary efficacy and safety endpoints (AF recurrence and procedure-related major complications) were pooled with the Comprehensive Meta-Analysis 3.0 software. Subgroup analyses were performed by age groups and type of procedure (radiofrequency vs. cryoballoon).

RESULTS

Four thousand eight hundred twenty-nine titles were screened, and 27 studies were included, being 26 observational and 1 randomized trial, comprising 117,869 patients, being 8714 (7.4%) elderly > 75/80 years, with follow-up from 11.7 to 72.3 months. In comparative studies (N = 17 studies), elderly > 75/80 years had a higher risk of AF recurrence compared to those ≤ 75/80: relative risk (RR) 1.16 (95% CI 1.05-1.27, p = 0.002. However, funnel plot indicated publication bias, and after imputation of 5 studies, the groups were similar (RR 1.07 (95% CI 0.97-1.19)). The rates of major complications (N = 14 studies) were higher in elderly > 75/80 years (RR 1.30 (95% CI 1.10-1.54), I2 = 0, p = 0.002), but were similar in cryoablation studies (N = 7) (RR 1.10, 95% CI 0.94-1.29, p = 0.24, I2 = 0.0). Results were similar when individual study arms (N = 27 studies) were pooled.

CONCLUSION

AF ablation is feasible in elderly patients > 75/80 years, with success rates compared to younger individuals. Complication rates, however, were higher.

Association of diabetes with atrial fibrillation types: a systematic review and meta-analysis

Background

Atrial fibrillation (AF) is a common arrhythmia classified as paroxysmal and non-paroxysmal. Non-paroxysmal AF is associated with an increased risk of complications. Diabetes contributes to AF initiation, yet its role in AF maintenance is unclear. We conducted a systematic review and meta-analysis to summarize the evidence regarding the association of diabetes with AF types.

Methods

We searched 5 databases for observational studies investigating the association of diabetes with the likelihood of an AF type (vs another type) in humans. Study quality was evaluated using the Newcastle–Ottawa Scale. Studies classifying AF types as paroxysmal (reference) and non-paroxysmal were pooled in a meta-analysis using random effects models.

Results

Of 1997 articles we identified, 20 were included in our systematic review. The population sample size ranged from 64 to 9816 participants with mean age ranging from 40 to 75 years and percentage of women from 24.8 to 100%. The quality of studies varied from poor (60%) to fair (5%) to good (35%). In the systematic review, 8 studies among patients with AF investigated the cross-sectional association of diabetes with non-paroxysmal AF (vs paroxysmal) of which 6 showed a positive association and 2 showed no association. Fourteen studies investigated the longitudinal association of diabetes with “more sustained” AF types (vs “less sustained”) of which 2 showed a positive association and 12 showed no association. In the meta-analysis of cross-sectional studies, patients with AF and diabetes were 1.31-times more likely to have non-paroxysmal AF than those without diabetes [8 studies; pooled OR (95% CI), 1.31 (1.13–1.51), I² = 82.6%]. The meta-analysis of longitudinal studies showed that for patients with paroxysmal AF, diabetes is associated with 1.32-times increased likelihood of progression to non-paroxysmal AF [five studies; pooled OR (95% CI), 1.32 (1.07–1.62); I² = 0%].

Conclusions

Our findings suggest that diabetes is associated with an increased likelihood of non-paroxysmal AF rather than paroxysmal AF. However, further high quality studies are needed to replicate these findings, adjust for potential confounders, elucidate mechanisms linking diabetes to non-paroxysmal AF, and assess the impact of antidiabetic medications on AF types. These strategies could eventually help decrease the risk of non-paroxysmal AF among patients with diabetes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-021-01423-2.