T wave Alternans. A Marker of Vulnerability to Ventricular Tachyarrhythmias

  • N. El-Sherif
Conference paper


Alternation of the configuration and/or duration of the repolarization wave of the electrocardiogram (ECG) — usually referred to as T wave alternans, and occasionally as ST alternans, U wave, or TU wave alternans — is seen under diverse experimental and clinical conditions (1,2). Interest in repolarization alternans is attributed to the hypothesis that it may reflect underlying dispersion of repolarization in the ventricle, a well-recognized electrophysiolgic substrate for reentrant ventricular tachyarrhythmias (3–6). Although overt T wave alternans in the ECG are not common, in recent years digital signal-processing techniques capable of detecting subtle degrees of T wave alternans have suggested that the phenomonem may be more prevalent than recognized and could represent an important marker of vulnerability to ventricular tachyarrhythmias (7–9). This report provides a brief review of the experimental and clinical conditions associated with T wave alternans and the electrophysiologic basis that links the phenomenon to ventricular vulnerability. Preliminary observations on a recently developed noninvasive technique to detect subtle T wave alternans will also be discussed (10).


Ventricular Tachyarrhythmia Purkinje Fiber Monophasic Action Potential Early Afterdepolarization Transmembrane Action Potential 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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  1. 1.
    Surawicz B, Fisch C (1992) Cardiac alternans. Diverse mechanisms and clinical manifestations. J Am Coll Cardiol 20: 483–499PubMedCrossRefGoogle Scholar
  2. 2.
    Verrier RL, Nearing BD (1994) Electrophysiologic basis for T wave alternans as an index of vulnerability to ventricular fibrillation. J Cardiovasc Electrophys 5: 445–461CrossRefGoogle Scholar
  3. 3.
    Han J, Moe GK (1964) Nonuniform recovery of excitability in ventricular muscle. Circ Res 14: 44–60PubMedGoogle Scholar
  4. 4.
    Cinca J, Figueras J, Senador G et al (1984) Transmural DC electrograms after coronary artery occlusion and latex embolization in pigs. Am J Physiol 246: H475 - H482PubMedGoogle Scholar
  5. 5.
    Dilly SG, Lab M (1988) Electrophysiological alternans and restitution during acute regional ischemia in myocardium of anesthesized pig. J Physiol (Lond) 402: 315–333Google Scholar
  6. 6.
    Janse MJ, Wit AL (1989) Electrophysiological mechanism of ventricular arrhythmias resulting from myocardial ischemia and infarction. Physiol Rev 69: 1049–1169PubMedGoogle Scholar
  7. 7.
    Smith JM, Clancy EA, Valeri CR et al (1988) Electrical alternans and cardiac electrical instability. Circulation 77: 110–21PubMedCrossRefGoogle Scholar
  8. 8.
    Nearing BD, Huang AH, Verrier RL (1991) Dynamic tracking of cardiac vulnerability by complex demodulation of the T wave. Science 252: 437–440PubMedCrossRefGoogle Scholar
  9. 9.
    Rosenbaum DS, Jackson LE, Smith JM et al (1994) Electrical alternans and vulnerability to ventricular arrhythmias. N Engl J Med 330: 235–241PubMedCrossRefGoogle Scholar
  10. 10.
    Eastes MNA, Zipes DP, El-Sherif N et al (1995) The value of T-wave alternans and signal-averaged electrocardiogram as predictors of arrhythmia vulnerability. Pace 18: 796 (Abstract)CrossRefGoogle Scholar
  11. 11.
    Saitoh H, Bailey JC, Surawicz B (1989) Action potential duration alternans in dog Purkinje and ventricular muscle fibers. Further evidence in support of two different mechanisms. Circulation 80: 1421–1431PubMedCrossRefGoogle Scholar
  12. 12.
    Hauswirth O, Noble D, Tsien RW (1972) The dependence of plateau currents in cardiac Purkinje fibers on the interval between action potentials. J Physiol (Lond) 222: 27–49Google Scholar
  13. 13.
    Boyett MR, Jewell BR (1978) A study of the factors responsible for rate-dependent shortening of the action potential in mammalian ventricular muscle. J Physiol (Lond) 285: 359–380Google Scholar
  14. 14.
    Kleber AG, Janse MJ, van Capelle FJL et al (1978) Mechanism and time course of S-T and T-Q segment changes during acute regional myocardial ischemia in the pig heart determined by extacellular and intracellular recordings. Circ Res 42: 603–613PubMedGoogle Scholar
  15. 15.
    Downar E, Janse MI, Durrer D (1977) The effect of acute coronary artery occlusion on subepicardial transmembrane potentials in the intact porcine heart. Circulation 56: 217–224PubMedGoogle Scholar
  16. 16.
    Russel DC, Smith HJ, Oliver MD (1979) Transmembrane potential changes and ventricular fibrillation during repetitive myocardial ischaemia in the dog. Br Heart J 42: 88–96.CrossRefGoogle Scholar
  17. 17.
    Konta T, Ikeda K, Yamaki M et al (1990) Significance of discordant ST alternans in ventricular fibrillation. Circulation 82: 2185–2189PubMedCrossRefGoogle Scholar
  18. 18.
    Antzelevitch C, Siccouri S, Litovsky S et al (1991) Heterogeneity within the ventricular wall: electrophysiology and pharmacology of epicardial, endocardial, and M cells. Circ Res 69: 1427–1449PubMedGoogle Scholar
  19. 19.
    El-Sherif N, Zeiler RN, Craelius W et al (1988) QTU prolongation and polymorphic ventricular tachyarrhythmias due to bradycardia-dependent early afterdepolarizations. Circ Res 63: 286–305PubMedGoogle Scholar
  20. 20.
    Gough WB, Henkin R (1989) The early afterdepolarization as recorded by the monophasic action potential technique: fact or artifact. Circulation 80:II-130 (Abstr)Google Scholar
  21. 21.
    Kleinfeld MJ, Rozanski JJ (1977) Alternans of the ST segment in Prinzmetal’s angina. Circulation 55: 574–577PubMedGoogle Scholar
  22. 22.
    Turitto G, El-Sherif N (1988) Alternans of the ST segment in variant angina. Chest 93: 587–591PubMedCrossRefGoogle Scholar
  23. 23.
    Gilchrist IC (1991) Prevalence and significance of ST segment alternans during coronary angioplasty. Am J Cardiol 68: 1534–1535PubMedCrossRefGoogle Scholar
  24. 24.
    Sutton PMI, Taggart P, Lab M et al (1991) Alternans of epicardial repolarization as a localized phenomenon in man. Eur Heart J 12: 70–78PubMedGoogle Scholar
  25. 25.
    Wayne VS, Bishop RL, Spodick DH (1983) Exercise-induced ST segment alternans. Chest 83: 824–825PubMedCrossRefGoogle Scholar
  26. 26.
    Puletti M, Curione M, Righetti G et al (1980) Alternans of the ST segment and T wave in acute myocardial infarction. J Electrocardiol 13: 297–300PubMedCrossRefGoogle Scholar
  27. 27.
    Salerno JA, Previtali M, Panciroli C et al (1988) Ventricular arrhythmias during acute myocardial ischaemia in man. The role and significance of R-ST-T alternans and the prevention of ischaemic sudden death by medical treatment. Eur Heart J 7: 63–75Google Scholar
  28. 28.
    Schwartz PJ, Maliani A (1975) Electrical alternation of the T wave: clinical and experimental evidence of its relationship with the sympathetic nervous system and with the long Q-T syndrome. Am Heart J 89: 45–50PubMedCrossRefGoogle Scholar
  29. 29.
    Jackman WM, Clark M, Friday KJ et al (1984) Ventricular tachyarrhythmias in the long QT syndrome. Med Clin North Am 68: 1079–1104PubMedGoogle Scholar
  30. 30.
    Reddy CVR, Riok JP, Khan RG et al (1984) Repolarization alternans associated with alcoholism and hypomagnesemia. Am J Cardiol 53: 390–391PubMedCrossRefGoogle Scholar
  31. 31.
    Habbab MA, El-Sherif N: (1992) TU alternans, long QTU, and torsade de pointes: clinical and experimental observations. PACE 15: 916–931PubMedCrossRefGoogle Scholar
  32. 32.
    Attwell D, Lee JA (1988) A cellular basis for the primary long QT syndromes. Lancet 1: 1136–1139PubMedCrossRefGoogle Scholar
  33. 33.
    El-Sherif N, Craeius W, Boutjdir M et al (1990) Early afterdepolarizations and arrhythmogenesis. J Cardiovasc Electrophysiol 1: 145–160.CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Italia, Milano 1996

Authors and Affiliations

  • N. El-Sherif
    • 1
  1. 1.Health Science Center and Veterans Affairs Medical CenterCardiology Division, State University of New YorkBrooklynUSA

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