|
|
||||||||
Cardiology Division, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215
Submitted 17 June 2003 ; accepted in final form 28 July 2003
Oscillations in T-wave morphology, particularly T-wave alternans (TWA), have been fundamentally linked to increased susceptibility to ventricular fibrillation (VF). We investigated whether the escalation in complexity of T-wave oscillations before VF is attributable to increased spatial heterogeneity of repolarization. Peak interlead T-wave heterogeneity (TWH) was measured by second central moment analysis of T-wave morphology in epicardial electrograms in dogs during left anterior descending coronary artery occlusion. TWH differentiated cases in which myocardial ischemia provoked VF from those without VF (563 ± 56 vs. 139 ± 36 µV, P < 0.01). In the former group, progressive, significant increases in TWH above preocclusion baseline (70 ± 8 µV) began at 2.25 min after the start of occlusion and were associated successively with TWA (at 155 ± 19 µV), T-wave multupling (at 386 ± 100 µV), complex oscillatory T-wave forms (at 560 ± 76 µV), discordant TWA (at 572 ± 98 µV), and VF at 4.36 ± 0.14 min. TWH in precordial ECGs in 12 pigs during angioplasty-balloon-induced myocardial ischemia also discriminated animals that experienced VF (from 90 ± 14 at baseline to 382 ± 39 µV, P < 0.05) from those without VF (from 96 ± 17 at baseline to 199 ± 61 µV, NS). Ischemia-induced changes in ST segment and T-wave amplitude did not predict VF. Heightened spatial heterogeneity of repolarization, as assessed by second central moment analysis of TWH, underlies TWA and increased risk for ischemia-induced VF. Monitoring spatial TWH from precordial leads could prove useful in stratifying risk for life-threatening arrhythmias.
sudden cardiac death; ventricular fibrillation; heterogeneity of repolarization
This article has been cited by other articles:
![]() |
T. Wisialowski, K. Crimin, J. Engtrakul, J. O'Donnell, B. Fermini, and A. A. Fossa Differentiation of Arrhythmia Risk of the Antibacterials Moxifloxacin, Erythromycin, and Telithromycin Based on Analysis of Monophasic Action Potential Duration Alternans and Cardiac Instability J. Pharmacol. Exp. Ther., July 1, 2006; 318(1): 352 - 359. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |