Is HATCH score a reliable predictor of atrial fibrillation after cavotricuspid isthmus ablation for typical atrial flutter?

OBJECTIVE: We determined the effectiveness of the HATCH score in patients with typical atrial flutter (AFl) undergoing cavotricuspid isthmus (CTI) ablation to predict long-term atrial fibrillation (AF). METHODS: We conducted an observational retrospective single-center cohort study including all patients admitted to our hospital for a CTI ablation between 1998 and 2010. The patients were divided into four categories: 1) new-onset AF (no prior AF and AF during follow-up (FU)); 2) old AF (prior AF and no AF during FU); 3) prior and post AF (AF prior and post CTI ablation); and 4) no AF. RESULTS: Four hundred and eight patients were included. In patients without prior AF, the hazard ratio (HR) for new-onset AF during FU was 0.98 (CI 95%: 0.65–1.50; p = 0.95) and 1.00 (CI 95%: 0.57–1.77; p = 0.98) for HATCH ≥ 2 and HATCH ≥ 3, respectively. In patients with prior AF, the HR for AF was 1.41 (CI 95%: 0.87–2.28; p = 0.17) and 1.79 (CI 95%: 0.96–3.35; p = 0.06), for HATCH ≥ 2 and HATCH ≥ 3, respectively. Left atrial enlargement was positively correlated with the occurrence of AF during FU, especially in the subgroup without prior AF, which had a HR of 2.44 (CI 95%: 1.35–4.40; p = 0.003), a HR of 2.88 (CI 95%: 1.36–6.10; p = 0.006) and a HR of 3.68 (CI 95%: 1.71–7.94; p = 0.001), for slight, moderate and severely dilated left atrial dimension, respectively, compared with a normal value. CONCLUSIONS: HATCH score did not predict AF in patients with typical AFl who underwent CTI ablation. Basal left atrium dimension could help predict new-onset AF.