Letter by De Ferrari and Verrier Regarding Article, “Role of Microvolt T-Wave Alternans in Assessment of Arrhythmia Vulnerability Among Patients With Heart Failure and Systolic Dysfunction: Primary Results From the T-Wave Alternans Sudden Cardiac Death in Heart Failure Trial Substudy”

Abstract

To the Editor: We read with interest the recent article by Gold et al,1 who concluded that T-wave alternans (TWA) should not be used to make clinical decisions for patients with symptomatic heart failure and left ventricular dysfunction. The accompanying editorial2 underscored as a major limitation the study’s use of an implantable cardioverter-defibrillator (ICD) discharge as a surrogate marker for sudden cardiac death, referencing a meta-analysis3 that demonstrated a dramatic difference in the predictive power of TWA if ICD-detected events were included or excluded. Although performing a TWA substudy within a large ICD trial was considered a major advantage,1 inclusion of ICD therapy actually prevented the determination of TWA’s prediction of clinical sudden death. An analysis excluding ICD-detected end points could be beneficial. However, end-point …