PREDICTORS OF MINIMAL CLINICALLY IMPORTANT DIFFERENCE OF QUALITY OF LIFE AND SEVERITY SCORE POST ATRIAL FIBRILLATION ABLATION

Abstract

Atrial fibrillation (AF) significantly impairs patients’ quality of life (QOL). We performed this study to investigate the effect of AF ablation success and AF burden (AFB) on change in QOL measures. Overall, 230 patients with paroxysmal AF refractory to anti-arrhythmic drugs were enrolled and underwent ablation in a multicenter, prospective cohort study. Electrocardiogram, 48-hour Holter monitoring, Canadian Cardiovascular Society Severity of Atrial Fibrillation (CCS-SAF), short-form12 (SF12) health survey, and Atrial Fibrillation Effect on Quality of life (AFEQT) scales were used to assess patients at 3, 6, 9 and 12-months post-ablation. AFB was defined as the total duration of AF during the month prior to each visit (hours/month). The change in AFB was calculated as the difference in AFB between the month prior to the 12-month post-ablation and the baseline pre-ablation visits. The Minimal Clinically Important Difference (MCID) was considered as a 19-point change for AFEQT and 3 to 5-point change for MCS and PCS scores. A total of 217 patients were followed for 12 months post-procedure. During the12-months post-ablation, freedom from any atrial tachyarrhythmia >30 seconds was 41.7%. Mean AFB at 12-months post ablation was 20.1±123.1 hours/month. In univariate regression analysis, baseline scores were significant predictors of change in QOL and severity score measures. Female gender was a significant predictor of change in AFEQT score, which predicted an increase of ΔAFEQT by 8.9 points. During 12-months of follow-up, complications predicted an increase in the CCS-SAF score by 1.2 points (P=0.003), redo-ablation significantly predicted a decrease in PCS score by 6.04 points (p=0.01), and cardioversion significantly predicted a decrease the AFEQT score by 9.6 points (p=0.009). Recurrence was a significant predictor of change in QOL and severity scores, which could predict and increase of 0.8 (P < 0.001) and decrease of 9.4 (P=0.008) and 4.8 (P=0.003) points in CCS-SAF, AFEQT and PCS, respectively. AFB < 24 hours/month at 12 months post-ablation significantly predicted a decrease in CCS-SAF by 1.9 (P < 0.001) points and increase in AFEQT and PSC scores by 19.5 (P < 0.001) and 5.5 (P=0.03) points respectively. Moreover, AFB < 24 hours/month at 12-months post-ablation was associated with significant changes in QOL and severity scale measures even when adjusting for baseline scores and other covariates in multivariate regression analysis, which were consistent with the MCID scores. (Table1) AFB less than 24 hours/month at 12-months post-procedure significantly improves QOL scores regardless of AF recurrence, to a degree consistent with the MCID of each QOL measure.