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A Research Method For Detecting Transient Myocardial Ischemia In Patients With Suspected Acute Coronary Syndrome Using Continuous ST-segment Analysis
18:11

A Research Method For Detecting Transient Myocardial Ischemia In Patients With Suspected Acute Coronary Syndrome Using Continuous ST-segment Analysis

Published on: December 28, 2012

Risk stratification for sudden cardiac death: is there a clinical role for T wave alternans?

Michael J Cutler1, David S Rosenbaum

  • 1Heart and Vascular Research Center, Case Western Reserve University, Cleveland, Ohio 44109-1998, USA.

Heart Rhythm
|July 28, 2009
PubMed

Insights

Sudden cardiac death (SCD) is increasing. Microvolt T-wave alternans (TWA) may improve risk stratification for implantable cardioverter-defibrillator (ICD) therapy beyond left ventricular ejection fraction (LVEF).

Area of Science:

  • Cardiology
  • Electrophysiology
  • Biomedical Engineering

Background:

  • Sudden cardiac death (SCD) represents a growing proportion of cardiovascular mortality.
  • Current risk stratification for prophylactic implantable cardioverter-defibrillators (ICDs) primarily relies on left ventricular ejection fraction (LVEF), which has limitations.
  • Identifying patients who will benefit from ICD implantation is crucial for reducing SCD.

Purpose of the Study:

  • To review the clinical utility of microvolt T-wave alternans (TWA) in risk stratification for SCD.
  • To explore TWA as a potential marker for arrhythmic risk beyond LVEF.
  • To discuss the role of TWA in guiding prophylactic ICD implantation decisions.

Main Methods:

  • Literature review of studies investigating TWA and SCD risk.
  • Analysis of TWA's association with electrophysiological substrates and arrhythmogenesis.
  • Evaluation of TWA's noninvasive assessment of arrhythmic risk.

Main Results:

  • T-wave alternans (TWA) at the microvolt level is emerging as a significant predictor of arrhythmic events.
  • TWA provides insights into the underlying electrophysiological substrate linked to arrhythmia mechanisms.
  • Evidence suggests TWA can enhance risk stratification for sudden cardiac death.

Conclusions:

  • Microvolt T-wave alternans (TWA) shows promise as a valuable tool for SCD risk stratification.
  • TWA may offer complementary information to LVEF in identifying patients for ICD therapy.
  • Further clinical integration of TWA could optimize prophylactic ICD implantation strategies.

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