ATLAS OF PACED BODY-SURFACE QRS INTEGRAL MAPS FOR LOCALIZATION OF THE SITE OF ORIGIN OF POSTINFARCTION VENTRICULAR-TACHYCARDIA

Current mapping during radiofrequency (RF) catheter ablation of postinfarction ventricular tachycardia (VT) is based primarily on the use of single-site mapping techniques. Although such techniques are highly suitable for distinguishing the ultimate site where RF energy is delivered by enabling detailed localization of the exit site or critical component of the VT reentrant circuit, they are time-consuming and inefficient for initial rapid identification of the arrhythmogenic target area. This study features the design and preliminary clinical application of a new noninvasive method that is aimed at speeding up the initial phase of the VT mapping procedure. This method is based on the use of an atlas of 62-lead body surface QRS integral map patterns that was previously developed using left ventricular pace mapping in patients with remote anterior or inferior myocardial infarction. The atlas contains 18 and 22 different paced QRS integral map patterns obtained in patients with previous anterior or inferior myocardial infarction, respectively. Each specific QRS pattern in the atlas provides a unique infarct-specific spatial electrocardiographic representation of the onset of ectopic ventricular activation in a circumscribed endocardial segment of the left ventricle. Localization of the segment of VT origin is obtained by visually or mathematically comparing the QRS integral map recorded during VT with one of the two sets of paced QRS integral maps contained within the atlas with the purpose of selecting the best matching paced QRS integral map pattern; During RF catheter ablation of postinfarction VT, body surface QRS integral mapping offers an efficient clinical tool that can be used as a first-step localization procedure that may guide subsequent catheter pace mapping or activation mapping quickly to the arrhythmogenic target area.