TRANSESOPHAGEAL MEASUREMENT OF LEFT ATRIAL REFRACTORINESS

During electrophysiological evaluation of supraventricular arrhythmias the transesophageal (TEEP) approach may be the first step but is limi ted in information available. One difficulty is in measuring left atri al refractoriness, as left atrial capture is seldom detectable either on ECG or via an esophageal lead. The problem may be eliminated and le ft atrial refractoriness measured via the esophagus, utilizing two or three extrastimuli to scan diastole to determine whether the atrial re fractory period has been entered by the first extrastimulus. Measureme nt of left atrial and/or atrioventricular node or accessory pathway re fractoriness then becomes possible.