T-wave altemans

Other noninvasive techniques to identify risk, such as baroreflex sensitivity, spectral turbulence (45 7), heart rate variability, T-wave altemans (48-51), QT interval prolongation, QT dispersion (52,53), and late potentials (by the signal averaged ECG) (54-56), have been considered in select patient populations (Table 14.2). AU have failed to live up to initial promises. 

The most novel of the noninvasive techniques involves evaluation of microvolt T-wave altemans (MTWA). This noninvasive diagnostic approach detects minute changes in electrical activity in the T-wave as it alternates in shape, amplitude, and timing beat by beat A positive MTWA test has been linked to inducible (48-51) and spontaneous (57,58) maUgnant ventricular arrhythmias. 

Kaufman, E.S., et al., Indeterminate microvolt T-wave altemans tests predict high risk of death or sustained ventricular arrhythmias in patients with left ventricular dysfunction. J Am Coll Cardiol, 2006. 48(7) p. 1399-404. 

Bloomfield, D.M., et al.. Microvolt T-wave altemans distinguishes between patients likely and patients not likely to benefit from implanted cardiac defibrillator therapy a solution to the Multicenter Automatic Defibrillator Implantation Trial (MADIT) II conundrum. Circulation, 2004.110(14) p. 1885-9. 

Gold, M.R., et al., T-Wave Altemans SCD HeFT Study Primary Endpoint Analysis. Circulation, 2006.114 p. II-428-9. 

Changes in Cardiac Electrical Systems with Detectable Precursors (T-wave altemans and heart rate variability)... 

Little, R.E., Kay, G.N., Cavender, J.B., Epstein, A.E., Plumb, V.J. (1990). Torsade de pointes and T-U wave altemans associated with arsenic poisoning. Pacing Clin. Electrophysiol. 13 164-70. 

Rozanski, J.J. and M. Kleinfeld, Altemans of the ST segment of T wave. A sign of electrical instability in Prinzmetal s angina. Pacing Clin Electrophysiol, 1982. 5(3) p. 359-65. 

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