Discrete Systolic Potentials During Ventricular Tachycardia in Patients with Prior Myocardial Infarction

Systolic Potent ia l s, introduction: Isolated diastolic potentials have been found to he helpfu! in identifyin; ^ critical.sites for ablation of ventricular tachycardia (VT) in patients with coronary artery disease. However, discrete potentials that occnr during systole have not been previously described. Tbe purpose of thi.s study was to determine the significance of discrete systolic potentials during VT in patients with coronary artery disease. Methods and Results: Twenty-seven patients witb a mean age of 66 ± 12 years ( ± standard deviation) who bad coronary artery disea.se underwent radiofrequency catbeter ablation of 42 VTs that had a mean cycle lengtb of 486 ± 78 msec. The only criterion used to select target sites for ablation was concealed entrainment, wbich was present at 92 sites. Thirly-five of tbe 42 VTs (83%) were snccessfully ablated. A discrete systolic potential was recorded during 7 of tbe 42 VTs (17%). In all cases, the interval between tbe discrete systolic potential and the next QRS complex was equal to tbe stimulus-QRS interval during concealed entrainment. At all seven sites wbere a discrete systolic potential was recorded, delivery of radiofrequency energy resulted in successful ablation of tbe VT. Conclusion: Discrete systolic potentials may be present in patients witb coronary artery disease in approximately 17 % of VTs in whicb tbere is concealed entrainment. If tbe interval between tbe discrete systolic potential and the next QRS complex matches tbe stimulus-QRS interval during concealed entrainment, delivery of radiofrequency energy is likely to result in successful ablation of tbe VT. (J Cardiovasc Electrophysiol, Vol. 10, pp. 364-S69, March 1999) concealed entrainment, systolic potential, ventricular tachycardi