[The diagnostic value of quantitative atrial activation mapping for localization of cardiac accessory pathways].

The diagnostic value of quantitative atrial activation mapping for localization of cardiac accessory pathways (AP) was evaluated in 50 cases with histories of supraventricular tachycardia (SVT). Some possible quantitative criteria are proposed for the differential diagnosis of free wall and septal APs. The diagnostic criteria of septal AP during SVT are 1) Slightly earlier left or right atrium depolarization; 2) time difference between left and right atrial depolarizations (delta A less than or equal to 30 ms; 3) change rate of delta A (delta A%) greater than 50%; 4) delta A index less than 10; and 5) ratio of ventriculo-atrial conduction times between the two atria less than 1.22. The sensitivity of these criteria in the diagnosis of cardiac septal AP is 91.7%, the specificity is 91.5% and the accuracy is 92%.