title: Electrocardiographic predictors of sudden cardiac death in patients with left ventricular hypertrophy.
abstract: BACKGROUND
  Left ventricular hypertrophy (LVH) has been associated with increased risk of sudden cardiac death (SCD), and improvements in risk stratification methodology are warranted.
  
  
  METHODS
  We evaluated electrocardiographic intervals as potential markers of SCD risk in LVH. Corrected QT, QRS, and JT intervals were evaluated in consecutive cases with SCD and LVH from the ongoing Oregon Sudden Unexpected Death study who underwent a 12-lead electrocardiogram (EKG) and echocardiogram prior to and unrelated to the SCD event. Comparisons of age, gender, body mass index, LV ejection fraction, and EKG intervals together with clinical conditions (hypertension and diabetes) were conducted with geographically matched controls that had coronary artery disease but no history of ventricular arrhythmias or cardiac arrest. LVH was determined using the modified American Society of Echocardiography equation for LV mass. Independent samples t-test, Pearson's chi-square test, and multiple logistic regression were used for statistical comparisons.
  
  
  RESULTS
  Of the 109 cases and 49 controls who met study criteria, age, gender, and comorbidities were similar among cases and controls. The mean LV mass index was not significantly different in cases compared to controls. However mean QTc (470.6 ± 53.6 ms vs 440.7 ± 38.7 ms; P < 0.0001) and QRS duration (113.6 ± 30.0 ms vs 104.9 ± 18.7 ms; P = 0.03) were significantly higher in cases than controls. In logistic regression analysis, prolonged QTc was the only EKG interval significantly associated with SCD (OR 1.72 [1.23-2.40]).
  
  
  CONCLUSIONS
  Prolonged QTc was independently associated with SCD among subjects with LVH and merits further evaluation as a predictor of SCD in LVH.
authors.affiliation: Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA.
authors.forename: Ragesh
authors.initials: R
authors.lastname: Panikkath
authors.forename: Kyndaron
authors.initials: K
authors.lastname: Reinier
authors.forename: Audrey
authors.initials: A
authors.lastname: Uy-Evanado
authors.forename: Carmen
authors.initials: C
authors.lastname: Teodorescu
authors.forename: Karen
authors.initials: K
authors.lastname: Gunson
authors.forename: Jonathan
authors.initials: J
authors.lastname: Jui
authors.forename: Sumeet S
authors.initials: SS
authors.lastname: Chugh
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D015897:Comorbidity; D016757:Death, Sudden, Cardiac / Q000209:etiology*; D004452:Echocardiography; D004562:Electrocardiography; D005260:Female; D006801:Humans; D017379:Hypertrophy, Left Ventricular / Q000150:complications* / Q000503:physiopathology*; D008297:Male; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012306:Risk