title: Elevated γ-glutamyltransferase in implantable cardioverter defibrillator patients.
abstract: BACKGROUND
  Elevated γ-glutamyltransferase (GGT) is a new risk factor for cardiovascular diseases, but its impact on ventricular tachyarrhythmia occurrence and survival in patients with an implantable cardioverter defibrillator (ICD) is unknown.
  
  
  RESULTS
  Considering that GGT levels are gender-dependent, female ICD recipients were excluded from our database because of the low incidence of events. In a retrospective analysis, appropriate ICD therapy (both shocks and antitachycardia pacing due to ventricular tachyarrhythmias) occurred in 31.9% of 320 male patients who had received an ICD for primary prevention (median follow-up of 2.3 years), and in 55.1% of 423 male patients who had received an ICD for secondary prevention (median follow-up of 3.9 years). Compared to normal low GGT plasma levels (below 28 U/L), total mortality but not risk for appropriate ICD therapy was elevated for higher GGT categories (p for trend = 0.004 in primary prevention and p for trend = 0.002 in secondary prevention, respectively). In Cox regression analysis, elevated GGT (>56 U/L) remained an independent predictor of death both in primary (p = 0.011) and in secondary prevention (p = 0.006). Patients with elevated GGT and renal insufficiency defined by an estimated glomerular filtration rate <60 ml/min/1.73 m(2) suffered from excess total mortality jeopardizing the benefit of ICD therapy.
  
  
  CONCLUSIONS
  Elevation of GGT is an important adverse prognostic parameter in ICD patients. A possible role of GGT for improved patient selection for ICD therapy deserves further investigation.
authors: Clinic for Internal Medicine III, Cardiology, Medical University Innsbruck, Innsbruck, Austria. dichtl@me.com
authors: Wolfgang
authors: W
authors: Dichtl
authors: Thomas
authors: T
authors: Wolber
authors: Ursula
authors: U
authors: Paoli
authors: Thomas
authors: T
authors: Theurl
authors: Simon
authors: S
authors: Brüllmann
authors: Markus
authors: M
authors: Stühlinger
authors: Thomas
authors: T
authors: Berger
authors: Karin
authors: K
authors: Spuller
authors: Alexander
authors: A
authors: Strasak
authors: Otmar
authors: O
authors: Pachinger
authors: Laurent
authors: L
authors: Haegeli
authors: Firat
authors: F
authors: Duru
authors: Florian
authors: F
authors: Hintringer
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001317:Austria / Q000453:epidemiology; D015415:Biomarkers / Q000097:blood; D015897:Comorbidity; D017147:Defibrillators, Implantable / Q000706:statistics & numerical data*; D004554:Electric Countershock / Q000401:mortality*; D005260:Female; D006333:Heart Failure / Q000097:blood* / Q000401:mortality / Q000517:prevention & control*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D018570:Risk Assessment / Q000379:methods; D012307:Risk Factors; D016019:Survival Analysis; D015996:Survival Rate; D013557:Switzerland / Q000453:epidemiology; D014693:Ventricular Fibrillation / Q000097:blood* / Q000401:mortality / Q000517:prevention & control*; D005723:gamma-Glutamyltransferase / Q000097:blood*
chemical_list: D015415:Biomarkers; D005723:gamma-Glutamyltransferase