August 1, 2005

James Rollins, MD, MSHA, PhD
Lead Medical Officer
Reference: CAG-00293N
NCA: Microvolt T-wave Alternans
Centers for Medicare and Medicaid Services
Department of Health and Human Services
P.O. Box 8011
Baltimore, MD 21244-1850.

Dear Dr. Rollins:

The Heart Rhythm Society is the international leader in science, education, and advocacy for cardiac arrhythmia professionals and patients, and the primary information resource on heart rhythm disorders. The Heart Rhythm Society’s mission is to improve the care of patients by promoting research, education, and optimal health care policies and standards. The Heart Rhythm Society’s 3,800 members are physicians, scientists and their support personnel who implant and/or follow pacemakers and implantable cardioverter defibrillators (ICDs) in patients who require these life-saving devices.

Because sudden cardiac death (SCD) prevention is one of our Society’s highest priorities, we are capable of providing evidence-based comments on the different tests that have been developed to aid in the risk stratification. One such test is Microvolt T-wave Alternans (MTWA). Although there are emerging data on the usefulness of MTWA in risk stratifying patients for SCD, these data are not enough to make this test standard of care. The best evidence for MTWA is in patients with ischemic or non-ischemic cardiomyopathy, but even in these patients the evidence is not strong enough to justify its use to select patients for an implantable cardioverter defibrillator (ICD). There are no data on the role of MTWA in patients surviving a VT/VF cardiac arrest, those with hypertrophic obstructive cardiomyopathy or those with primary electrophysiologic abnormalities.

The Heart Rhythm Society believes that more prospective studies are needed to further delineate the role of MTWA in selecting patients for an ICD. The prospective clinical trial (ABCD), the SCD-HeFT sub-study, and other studies of MTWA are expected to yield more information regarding the usefulness of this test. Until more data are gathered and analyzed, the Society can not support the routine use of MTWA in selecting patients for an ICD or making this test a required element of the National ICD Registry. Despite these limitations, the Heart Rhythm Society believes that MTWA, in combination with other clinical information including the Signal-Averaged ECG that is currently covered by CMS, may be useful in assessing the risk of certain patients for ventricular arrhythmias.

Thank you very much for your consideration of these comments.  If you need to contact us, please contact Amy Melnick at amelnick@hrsonline.org or 202-464-3434.  

Sincerely,

Anne B. Curtis, MD, FACC
President, Heart Rhythm Society