title: Left ventricular diameter and risk stratification for sudden cardiac death.
abstract: BACKGROUND
  Left ventricular (LV) diameter is routinely measured on the echocardiogram but has not been jointly evaluated with the ejection fraction (EF) for risk stratification of sudden cardiac death (SCD).
  
  
  RESULTS
  From a large ongoing community-based study of SCD (The Oregon Sudden Unexpected Death Study; population ≈1 million), SCD cases were compared with geographic controls. LVEF and LV diameter, measured using the LV internal dimension in diastole (categorized as normal, mild, moderate, or severe dilatation using American Society of Echocardiography definitions) were assessed from echocardiograms prior but unrelated to the SCD event. Cases (n=418; 69.5±13.8 years), compared with controls (n=329; 67.7±11.9 years), more commonly had severe LV dysfunction (EF ≤35%; 30.5% versus 18.8%; P<0.01) and larger LV diameter (52.2±10.5 mm versus 49.7±7.9 mm; P<0.01). Moderate or severe LV dilatation (16.3% versus 8.2%; P=0.001) and severe LV dilatation (8.1% versus 2.1%; P<0.001) were significantly more frequent in cases. In multivariable analysis, severe LV dilatation was an independent predictor of SCD (odds ratio 2.5 [95% CI 1.03 to 5.9]; P=0.04). In addition, subjects with both EF ≤35% and severe LV dilatation had higher odds for SCD compared with those with low EF only (odds ratio 3.8 [95% CI 1.5 to 10.2] for both versus 1.7 [95% CI 1.2 to 2.5] for low EF only), suggesting that severe LV dilatation additively increased SCD risk.
  
  
  CONCLUSIONS
  LV diameter may contribute to risk stratification for SCD independent of the LVEF. This readily available echocardiographic measure warrants further prospective evaluation.
authors.affiliation: Cedars Sinai Medical Center, Los Angeles, CA (K.N., K.R., C.T., A.U.E., H.C., S.S.C.).
authors.forename: Kumar
authors.initials: K
authors.lastname: Narayanan
authors.affiliation: Cedars Sinai Medical Center, Los Angeles, CA (K.N., K.R., C.T., A.U.E., H.C., S.S.C.).
authors.forename: Kyndaron
authors.initials: K
authors.lastname: Reinier
authors.affiliation: Cedars Sinai Medical Center, Los Angeles, CA (K.N., K.R., C.T., A.U.E., H.C., S.S.C.).
authors.forename: Carmen
authors.initials: C
authors.lastname: Teodorescu
authors.affiliation: Cedars Sinai Medical Center, Los Angeles, CA (K.N., K.R., C.T., A.U.E., H.C., S.S.C.).
authors.forename: Audrey
authors.initials: A
authors.lastname: Uy-Evanado
authors.affiliation: University of Colorado, Denver, CO (R.A.).
authors.forename: Ryan
authors.initials: R
authors.lastname: Aleong
authors.affiliation: Cedars Sinai Medical Center, Los Angeles, CA (K.N., K.R., C.T., A.U.E., H.C., S.S.C.).
authors.forename: Harpriya
authors.initials: H
authors.lastname: Chugh
authors.affiliation: Kaiser Permanente, Portland, OR (G.A.N.).
authors.forename: Gregory A
authors.initials: GA
authors.lastname: Nichols
authors.affiliation: Oregon Health and Science University, Portland, OR (K.G., J.J.).
authors.forename: Karen
authors.initials: K
authors.lastname: Gunson
authors.affiliation: University of Iowa, Iowa City, IA (B.L.).
authors.forename: Barry
authors.initials: B
authors.lastname: London
authors.affiliation: Oregon Health and Science University, Portland, OR (K.G., J.J.).
authors.forename: Jonathan
authors.initials: J
authors.lastname: Jui
authors.affiliation: Cedars Sinai Medical Center, Los Angeles, CA (K.N., K.R., C.T., A.U.E., H.C., S.S.C.).
authors.forename: Sumeet S
authors.initials: SS
authors.lastname: Chugh
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D002423:Cause of Death; D016757:Death, Sudden, Cardiac / Q000453:epidemiology*; D015150:Echocardiography, Doppler; D005260:Female; D005500:Follow-Up Studies; D006352:Heart Ventricles / Q000000981:diagnostic imaging* / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012189:Retrospective Studies; D018570:Risk Assessment; D017678:Sex Distribution; D013318:Stroke Volume / Q000502:physiology*; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000401:mortality* / Q000503:physiopathology
keywords: LV diameter; ejection fraction; risk stratification; sudden cardiac death