title: High prevalence of right ventricular dysfunction in ICD patients with shocks: a potential new predictor in risk stratification.
abstract: BACKGROUND
  Despite identifying several risk factors for sudden cardiac death, our ability to predict arrhythmic events in patients with an implantable cardioverter defibrillator (ICD) remains poor. The purpose of this study was to determine if patients who received appropriate ICD shocks had a higher degree of right ventricular (RV) dysfunction at baseline when compared to patients who did not receive ICD shocks.
  
  
  METHODS
  We conducted a 1:2 case-control, retrospective study comparing RV end-diastolic and end-systolic areas (RV ED and RV ES areas, respectively), fractional RV area change, and RV wall thickness in 19 consecutive patients who received appropriate ICD shocks (shock group) with another group of 38 patients who did not receive ICD shocks (no-shock group).
  
  
  RESULTS
  There was no significant difference in the RV end-diastolic areas between the groups. However, patients who experienced ICD shocks had a higher RV end-systolic area and a lower RV fractional area change when compared to patients without ICD shocks, 16.3 ± 4.9 cm(2) and 27.7 ± 9.0% in the shock group versus 14.2 ± 4.4 cm(2) and 35.8 ± 10.3% in the no-shock group; (p = 0.08 and 0.004, respectively). Furthermore, the RV wall thickness was greater in patients with ICD shocks when compared to patients without ICD shocks, 0.49 ± 0.05 cm and 0.44 ± 0.04 cm, respectively (p = 0.001). Utilizing a logistic regression analysis and after controlling for variables with univariate significance (p < 0.1), RV wall thickness independently predicted ICD shocks (OR 13.9 mm(-1) change of RV thickness, p = 0.004).
  
  
  CONCLUSIONS
  Our findings suggest that some measurements of RV function might prove to be useful in predicting future arrhythmic events. Additional prospective studies are needed to test this hypothesis.
authors.affiliation: University of Utah, Salt Lake City, UT, USA.
authors.forename: Gangadhar
authors.initials: G
authors.lastname: Malasana
authors.forename: Marcos
authors.initials: M
authors.lastname: Daccarett
authors.forename: Suman
authors.initials: S
authors.lastname: Kuppahally
authors.forename: Stephen L
authors.initials: SL
authors.lastname: Wasmund
authors.forename: Sheldon E
authors.initials: SE
authors.lastname: Litwin
authors.forename: Mohamed H
authors.initials: MH
authors.lastname: Hamdan
mesh_terms: D017677:Age Distribution; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D016757:Death, Sudden, Cardiac / Q000453:epidemiology* / Q000209:etiology; D017147:Defibrillators, Implantable / Q000009:adverse effects*; D004562:Electrocardiography; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D015995:Prevalence; D012016:Reference Values; D012189:Retrospective Studies; D018570:Risk Assessment; D012720:Severity of Illness Index; D017678:Sex Distribution; D016019:Survival Analysis; D017180:Tachycardia, Ventricular / Q000175:diagnosis / Q000453:epidemiology*; D018487:Ventricular Dysfunction, Left / Q000453:epidemiology* / Q000209:etiology; D014693:Ventricular Fibrillation / Q000175:diagnosis / Q000453:epidemiology*