Atrial fibrillation recurrence risk after single catheter ablation in patients with history of hyperthyroidism: systematic review and meta-analysis

Background Atrial fibrillation (AF) is the most common arrhythmias. Other than pharmacotherapy, catheter ablation is preferred especially for symptomatic paroxysmal AF or persistent AF. However, recurrence of atrial fibrillation following catheter ablation can occur due to several factors. Hyperthyroidism is known as a factor in atrial fibrillation pathogenesis but its role in AF recurrence following ablation is not known yet. Therefore, we aimed to assess the recurrence risk after catheter ablation in patients with a history of hyperthyroidism. Methods Systematic searching was performed through three databases: MEDLINE, EMBASE, and SCOPUS for studies reporting the recurrence of AF (hazard ratio) following catheter ablation in patients with a history of hyperthyroidism. The risk of bias assessment of included studies was performed using quality in prognosis studies (QUIPS). Meta-analysis (random effect model and inverse variance) was conducted using RevMan software version 5.4. Results Four studies involving 837 subjects were included. Pooled analysis shows a higher risk of recurrence of atrial fibrillation following catheter ablation in patients with history of hyperthyroidism (HR 1.86 [CI 95% 1.26–2.75]; I 2 38%). Subgroup analysis showed patients with amiodarone-induced hyperthyroidism (AIH) had a higher risk of atrial fibrillation recurrence (HR 2.31; CI 95% 1.49–3.58; I 2 0%) compared to non-AIH. However, two studies on AIH showed moderate risk of bias. Conclusions History of hyperthyroidism was found as the risk of recurrence of atrial fibrillation after a single ablation procedure. Patients with amiodarone-induced hyperthyroidism have a higher recurrence risk. Further studies with larger participants are needed for subgroup analysis on specific parameters of the ablation.