title: Microvolt T-wave alternans in end-stage renal disease patients--associations with uremic cardiomyopathy.
abstract: OBJECTIVE
  Premature cardiovascular (CV) events, especially sudden cardiac death, are common in ESRD patients and associated with uremic cardiomyopathy. Identification of high-risk patients is difficult. Microvolt T-wave alternans (MTWA) is a noninvasive method of detecting variability in electrocardiogram (ECG) T-wave morphology and is a promising technique for identifying patients at high risk of ventricular tachyarrhythmias. MTWA results of ESRD and hypertensive left ventricular hypertrophy (LVH) patients were assessed to determine the prevalence of abnormal results and associations with uremic cardiomyopathy.
  
  
  METHODS
  In this single-center observational study, 200 ESRD and 30 LVH patients underwent assessment including CV history, ECG, cardiac magnetic resonance imaging, and an MTWA exercise test. MTWA results were classified as "negative" or "abnormal" on the basis of previously published reports.
  
  
  RESULTS
  An abnormal MTWA result was more common in ESRD compared with LVH patients (57.5% versus 26.7%, respectively; P = 0.002). In ESRD patients, MTWA was significantly associated with uremic cardiomyopathy, clinical history of atherosclerosis (coronary, cerebral, peripheral) and diabetes mellitus, older age, and hemodialysis therapy. Independent associations with an abnormal MTWA result were older age, macrovascular disease, increased left ventricle (LV) mass, and LV dilation.
  
  
  CONCLUSIONS
  Features of uremic cardiomyopathy are associated with an abnormal MTWA result.
authors.affiliation: British Heart Foundation Glasgow Cardiovascular Research Centre, University of Glasgow, Glasgow, UK. r.patel@clinmed.gla.ac.uk
authors.forename: Rajan K
authors.initials: RK
authors.lastname: Patel
authors.forename: Patrick B
authors.initials: PB
authors.lastname: Mark
authors.forename: Crawford
authors.initials: C
authors.lastname: Halliday
authors.forename: Tracey
authors.initials: T
authors.lastname: Steedman
authors.forename: Henry J
authors.initials: HJ
authors.lastname: Dargie
authors.forename: Stuart M
authors.initials: SM
authors.lastname: Cobbe
authors.forename: Alan G
authors.initials: AG
authors.lastname: Jardine
mesh_terms: D000328:Adult; D000368:Aged; D009202:Cardiomyopathies / Q000175:diagnosis / Q000209:etiology* / Q000401:mortality / Q000503:physiopathology; D016009:Chi-Square Distribution; D017023:Coronary Angiography; D016757:Death, Sudden, Cardiac / Q000209:etiology*; D004562:Electrocardiography; D005260:Female; D006329:Heart Conduction System / Q000503:physiopathology*; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000150:complications* / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology; D053208:Kaplan-Meier Estimate; D007676:Kidney Failure, Chronic / Q000150:complications* / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology; D016015:Logistic Models; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D018570:Risk Assessment; D012307:Risk Factors; D012606:Scotland; D017180:Tachycardia, Ventricular / Q000175:diagnosis / Q000209:etiology* / Q000401:mortality / Q000503:physiopathology; D014511:Uremia / Q000175:diagnosis / Q000209:etiology* / Q000401:mortality / Q000503:physiopathology