Po-04-006 baseline conduction intervals and surface p wave characteristics predict atrial fibrillation occurrence after atrial flutter ablation

Prevalence of atrial fibrillation (AF) in patients with typical, cavotricuspid isthmus dependent, atrial flutter (tAFL) is higher than in patients without tAFL. Correlation between atrial conduction parameters and other markers of atrial myopathy during tAFL ablation and prevalence of AF has not been described. To investigate which intraatrial and interatrial conduction parameters and electrogram characteristics measured during tAFL ablation correlate with prevalence and incidence of AF during follow-up. We performed a retrospective analysis of consecutive patients that underwent tAFL ablation. We measured EKG parameters including surface P wave duration, morphology and intracardiac conduction intervals and electrogram characteristics. 158 patients with tAFL were analyzed. The mean age was 63±9 years, of which 126 were male. Clinical factors such as diabetes, hypertension, coronary artery disease, the HATCH score (ordinal scoring system for risk of AF development), and left atrial (LA) size all were associated with increased risk of development of AF (p value <0.05). Surface P wave characteristics such as P wave duration and morphology did not correlate with development of AF. However, the intracardiac conduction characteristics: proximal coronary sinus (pCS) electrogram fractionation, pCS electrogram duration, pCS to distal coronary sinus (dCS) electrogram timing, and pCS to dCS >70ms were all significant predictors for AF development (p-value <0.001) during a mean follow up of 291±403 days. In patients undergoing tAFL ablation, along with known clinical risk factors, LA size, HATCH score, pCS electrogram fractionation/duration, pCS to dCS duration (particularly pCS to dCS>70ms) correlate with a higher prevalence of AF. These parameters are likely markers of atrial myopathy and may help guide aggressiveness of AF monitoring in patients presenting for tAFL ablation.