title: Heart rate turbulence after short runs of nonsustained ventricular tachycardia in chronic heart failure.
abstract: BACKGROUND
  Heart rate turbulence (HRT) following isolated premature complexes is a baroreceptor-mediated prognostic marker. Short runs of spontaneous, nonsustained ventricular tachycardia (nsVT) exert a greater hemodynamic effect than extrasystoles and may trigger a more potent turbulence-like response (HRT(VT)), possibly related to other risk-related markers, such as heart rate variability (HRV), left ventricular ejection fraction (EF), and original HRT parameters (turbulence slope [TS] and turbulence onset [TO]).
  
  
  METHODS
  We studied 27 patients with heart failure (HF) and nsVT (4-7 beats) on 24-hour Holter electrocardiographic recordings (mean age 58 +/- 3.6 years, EF 36%+/- 5.0%). Following nsVT, TS(VT) and TO(VT) were measured according to the original definitions. HRV, TS, and TO were also assessed.
  
  
  RESULTS
  HRT(VT) parameters were related to HRV. A significant relation existed between TS(VT) and EF (r= 0.66, P < 0.05). HRT(VT) parameters were related to the originally described (TS and TO), whereas TO(VT) was higher than TO (1.63 +/- 1.6 vs -1.7 +/- 0.65, P < 0.05).
  
  
  CONCLUSIONS
  In mild-to-moderate HF, turbulence is observed following short nsVT runs and is related to prognostically important HRV indexes and EF. HRT(VT) is similar to HRT but TO(VT) is shifted toward more positive values than TO. HRT(VT) might be prognostically significant.
authors.affiliation: Second Department of Cardiology, Onassis Cardiac Surgery Center, Athens, Greece. pflevari@yahoo.com
authors.forename: Panayota
authors.initials: P
authors.lastname: Flevari
authors.forename: Panagiota
authors.initials: P
authors.lastname: Georgiadou
authors.forename: Dionyssios
authors.initials: D
authors.lastname: Leftheriotis
authors.forename: Efthimios
authors.initials: E
authors.lastname: Livanis
authors.forename: George
authors.initials: G
authors.lastname: Theodorakis
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Th Kremastinos
mesh_terms: D002908:Chronic Disease; D015716:Electrocardiography, Ambulatory; D005260:Female; D006333:Heart Failure / Q000503:physiopathology*; D006339:Heart Rate; D006801:Humans; D008297:Male; D008875:Middle Aged; D013318:Stroke Volume; D017180:Tachycardia, Ventricular / Q000503:physiopathology*