Catheter ablation for atrial fibrillation in hypertrophic cardiomyopathy: a systematic review and meta-analysis.

OBJECTIVE: Atrial fibrillation (AF) is common in hypertrophic cardiomyopathy (HCM) and is associated with a high risk of stroke. The efficacy and safety of catheter ablation in this setting is poorly characterised. We aimed to systematically review the existing literature and to perform a meta-analysis to determine the efficacy and safety of catheter ablation of AF in patients with HCM. METHODS: Random-effects meta-analysis of studies comparing HCM versus non-HCM controls. The outcomes of freedom from AF/atrial tachycardia, and acute procedure-related complications were assessed. Studies were searched on MEDLINE, EMBASE, COCHRANE and clinicaltrials.gov. RESULTS: Fourteen studies were considered eligible for the systematic review, of which five were included in the meta-analysis. Freedom from AF/atrial tachycardia relapse was higher in patients without HCM (after a single procedure: 38.7% HCM vs 49.8% controls, OR=2.25, 95% CI 1.09 to 4.64, p=0.03; after ≥1 procedure: 51.8% HCM vs 71.2% controls, OR=2.62, 95% CI 1.52 to 4.51, p=0.0006; I(2)=33% and 26%, respectively). Risk of procedure-related adverse events was low. Repeat procedures (mean difference=0.16, 95% CI 0.0 to 0.32, p=0.05, I(2)=53%) and antiarrhythmic drugs (OR=4.70, 95% CI 2.31 to 9.55, p<0.0001, I(2)=0%) are more frequently needed in patients with HCM to prevent arrhythmia relapse. Sensitivity analyses suggested that the outcome in patients with HCM with less dilated atria and paroxysmal AF may be more comparable to the general population. CONCLUSIONS: The observed complication rate of catheter ablation of AF in patients with HCM was low. Even though the risk of relapse is twofold higher, catheter ablation can be effective in patients with HCM and AF, particularly in patients with paroxysmal AF and smaller atria.

Expert OpinionShould We Let Sleeping Dogs Lie? Controversies of Treating Central Sleep Apnoea in HFrEF Following the SERVE-HF Study.

Central sleep apnoea (CSA) is common in patients with heart failure (HF), with a prevalence of 20-45 %. It is a marker of severity of HF and is independently associated with increased morbidity and mortality rates in patients with HF. Targeting CSA with adaptive servoventilation (ASV) was postulated to improve outcomes; however, the results of the recent SERVE-HF (Treatment of Sleep-disordered Breathing by Adaptive Servo-ventilation in Heart Failure Patients) trial showed that in patients with CSA and HF with reduced ejection fraction (HFrEF), ASV, despite successfully treating CSA, was associated with increased risk of cardiovascular death compared with medical therapy. In this expert opinion we discuss the controversies of treating CSA in HFrEF following the SERVE-HF study.