Abstract 14302: Prediction of Conduction Velocity Based on Amplitude for Identification of Atrial Flutter Reentry
Local conduction velocity (LCV) in the low amplitude electrogram area is generally low. The quantitative relationship between LCV and bipolar electrogram amplitude (biEA) in the atria remains unclear. We analyzed the reentry circuit of atrial flutter (AFL) in the right atrium (RA), focusing on LCV and biEA on the circuit.
Methods and Results. Twenty-six patients with RA AFL (10 with typical AFL (Group T), 10 incisional AFL (Group I) and 6 non-incisional AFL (Group NI)) were studied using CARTO XP and 4-mm tip catheter. After identification of the reentrant circuit, atrial points activated faster than the neighboring ones on the circuit were identified by isochronal and propagation maps during AFL. LCV was calculated by dividing the distance between the 2 neighboring points on the circuit by the time difference. A total of 194 points were obtained from 26 AFL circuits (7±2 points/AFL), and there was a highly significant positive correlation between LCV and natural logarithm of the peak-to-peak biEA (LbiEA ) (R2 0.821, P 0.001). Linear regression analysis of mean conduction velocity, which was calculated by dividing the circuit length by tachycardia cycle length (TCL), and mean, which was calculated by dividing area under a curve (AUC) of during one tachycardia cycle by TCL, demonstrated a y-intercept of 0.694 and a slope of 0.192 (R2=0.992, P<0.001)(Figure). Mean circuit length (mm) was significantly longer in Group T (185.4±20.4) than in Group I (136.6±41.1, P=0.008) and Group NI (123.1±34.7, P=0.04). Mean AUC of LbiEA was significantly higher in Group T (134.0±61.4) than in Group I (-284.7±301.2, P=0.004) and Group NI (-379.2±162.3, P=0.001). In conclusion, the peak-to-peak biEA was most significantly correlated with LCV on the reentrant circuit. Thus, the lower biEA is, the slower LCV is, and consequently, the reentrant circuit is small as well.
- © 2011 by American Heart Association, Inc.