title: Mean frequency of premature ventricular complexes as predictor of malignant ventricular arrhythmias.
abstract: OBJECTIVE
  The aim was to test the hypothesis that mean frequency of premature ventricular complexes (PVCs) correlates with vulnerability to malignant arrhythmias such as ventricular tachycardia and/or ventricular fibrillation (VT/VF).
  
  
  METHODS
  Patients with an implantable cardioverter defibrillator (ICD) device for underlying ischemic or non-ischemic cardiac pathology were selected from a database. Availability of total count of single (s) PVCs and runs (r) of PVCs was the only inclusion criterion. Forty-four subjects (6 females and 38 males) aged 18-74 years (mean 547.1 years), were eligible. All had a European Pacemaker Identification Card (EPIC) documenting left ventricular ejection fraction (LVEF). The frequency of recorded episodes of VT and VF was obtained from ICD memory.
  
  
  RESULTS
  Among patients with ischemic heart disease (IHD) and those with IHD and an LVEF of less than 30%, the mean frequency of PVCs was significantly higher in those with subsequent episodes of VT/VF compared to those without subsequent episodes (p < 0.05 for sPVCs and rPVCs in both groups).
  
  
  CONCLUSIONS
  Among patients with IHD, mean frequency of PVCs is a useful marker of vulnerability to potentially fatal arrhythmias and may be a useful tool for the risk stratification of patients.
authors.affiliation: College of Medicine, University of Edinburgh, Scotland, United Kingdom. zia.carrim@doctors.org.uk
authors.forename: Zia I
authors.initials: ZI
authors.lastname: Carrim
authors.forename: Ashraf A
authors.initials: AA
authors.lastname: Khan
mesh_terms: D000328:Adult; D000368:Aged; D016009:Chi-Square Distribution; D017147:Defibrillators, Implantable; D005260:Female; D006331:Heart Diseases / Q000150:complications / Q000628:therapy; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D018709:Statistics, Nonparametric; D017180:Tachycardia, Ventricular / Q000209:etiology*; D014693:Ventricular Fibrillation / Q000209:etiology*; D018879:Ventricular Premature Complexes / Q000150:complications*