Morphological Characteristics Of P-wave During Selective Veins Within The Chest Pacing

Objective:The purpose of this study was morphological characteristics of P-wave during selective veins within the chest pacing and to discriminate atrial arrhythmia that can induce atrial fibrillation and to diagnosis value.Methods:A total of35paroxysmal atrial fibrillation patients who were refractory to or intolerant of antiarrhythmic drugs were included. Routine placement electrode of the high right atrium, the coronary sinus and right ventricular. A quadripolar ablation catheter was advanced to veins within the chest, and then pacing inside veins within the chest was performed before radiofrequency ablation of PAF. The P-wave amplitude, duration and morphology were assessed and analyzed.Results:Comparing to P wave of sinus rhythm, there were not only statistically significant in P wave duration of atrial arrhythmia originated from the veins within the chest in all leads, but also the amplitude of P wave in limbs leads, but there was no significant differences in chest leads. Left pulmonary vein of P wave duration longer then the right pulmonary vein of P waves;superior vena cava P wave duration longer than the sinus rhythm of P wave duration;and the right pulmonary vein of P wave duration longer than the superior vena cava of P wave duration. superior pulmonary vein of P wave amplitude higher than inferior pulmonary vein of P wave amplitude;superior vena cava of P wave amplitude higher than sinus rhythm of P wave amplitude. veins within the chest origin the polarity of the P wave in chest leads to positive, sinus rhythm and superior vena cava the polarity of the P wave in lead V1～2is positive negative and double and other precordial lead is positiveAt the same time, when the amplitude of P wave in lead I was <55uV or negative deflection in lead I, they showed the highest sensitivity (100%) as a predictor of left PV origin but low specificity. A high lead aVL/I amplitude ratio(>1.55) demonstrated in70%sensitivity and85%specificity for identifying left PV origin. A positive P wave in lead aVL or non-negative polarity in lead V1was associated with a high sensitivity of100%for sinus rhythm or SVC origin. The P wave amplitude ratio of lead aVF/I (≥1.8) showed88.6%sensitivity for SVC origin when the P wave amplitude of lead aVF (≥95uV) could be used to diagnose superior or inferior PV origin with the sensitivity of94.3%.Conclusions:Characteristic P-wave morphology is corresponded to identify the sites of origin for focal AT originating from veins within the chest with high specificity and sensitivity.