Potential mapping in septal tachycardia. Evaluation of a new intraoperative mapping technique.
A recently developed computer program is capable of rapidly (less than 5 minutes) constructing a series of potential-distribution maps (PDMs) for every msec of a 4-second window of ventricular tachycardia (VT). This study was performed to assess the ability of a series of PDMs to localize the site of earliest activation of VT originating in the interventricular septum. In 12 dogs, 13 morphologies of VT were initiated with programmed electrical stimulation 3-6 days after anterior septal coronary artery infarction. VT was mapped with endocardial and epicardial unipolar electrodes with a multipoint, computer-assisted mapping system. PDMs were compared with activation-time maps, and the former correctly identified the site of earliest activation of all 13 VT morphologies. When PDMs were viewed in sequence on a computer monitor, the site of earliest activation was signaled by abrupt development of a negative potential of less than -3.0 mV. The initial negative point subsequently expanded, and the spread of this negative-potential field correlated with activation sequence. PDMs provide an accurate, unambiguous, rapid means of analyzing large numbers of electrograms acquired with multipoint, computer-assisted mapping systems.
Tweddell
J S
JS
Department of Surgery, Washington University School of Medicine, St. Louis, MO 63110.
Branham
B H
BH
Harada
A
A
Stone
C M
CM
Rokkas
C K
CK
Schuessler
R B
RB
Boineau
J P
JP
Cox
J L
JL
D000200:Action Potentials; D000703:Analog-Digital Conversion; D000818:Animals; D002304:Cardiac Pacing, Artificial / Q000379:methods; D003936:Diagnosis, Computer-Assisted / Q000295:instrumentation / Q000379:methods; D004195:Disease Models, Animal; D004285:Dogs; D004562:Electrocardiography / Q000295:instrumentation / Q000379:methods*; D004566:Electrodes; D005260:Female; D006346:Heart Septum / Q000503:physiopathology*; D007430:Intraoperative Care / Q000379:methods*; D008297:Male; D012984:Software; D013610:Tachycardia / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery