title: Patient selection for biventricular pacing.
abstract: BACKGROUND
  Biventricular pacing improves functional status in the majority of patients with drug-refractory heart failure, dilated cardiomyopathy, and interventricular conduction delay. The aim of this study was to analyze the baseline clinical and functional data of a cohort of patients implanted with a biventricular stimulation system in a single-center experience, to verify if the pathophysiologic characteristics of patients affect outcome, and to determine if preliminary identification of the right candidates for the new therapy is possible with noninvasive parameters.
  
  
  RESULTS
  Since March 1999, 52 patients with advanced heart failure (idiopathic cardiomyopathy 50%, ischemic cardiomyopathy 35%, other etiology 15%) and left bundle branch block underwent cardiac resynchronization and were followed prospectively. Paired analysis over mean (+/- SD) follow-up of 348 +/- 154 days showed an overall significant decrease of QRS width (baseline 194 +/- 33.2 msec vs follow-up 159.6 +/- 20.1 msec), New York Heart Association (NYHA) functional class (baseline 3.2 +/- 0.5 vs follow-up 2.3 +/- 0.5), quality-of-life score (baseline 54 +/- 25 vs follow-up 25 +/- 16), and increase of maximal VO2 (baseline 12.6 +/- 2.5 mL/kg/min vs follow-up 15.0 +/- 3.3 mL/kg/min). There were 80% responders (documented, persistent decrease > or = 1 NYHA class) and 20% nonresponders (same NYHA class or decline of status; need for heart transplant; death due to progressive pump failure). No significant differences in baseline clinical and functional variables between the two subgroups were observed. In responders, there was a highly significant global improvement of all variables; in nonresponders, no parameters changed between baseline and follow-up.
  
  
  CONCLUSIONS
  These data confirm the role of biventricular pacing in improving the functional status of the great majority of a selected patient population having advanced heart failure and left bundle branch block with wide QRS complex. Basal demographic, clinical, and functional characteristics are not helpful in preliminary selection of responders. Simple evaluation of NYHA class confirms favorable outcome (improvement of functional and hemodynamic status).
authors.affiliation: Department of Cardiology De Gasperis, Niguarda Hospital, Milan, Italy. infodega@tin.it
authors.forename: Maurizio
authors.initials: M
authors.lastname: Lunati
authors.forename: Marco
authors.initials: M
authors.lastname: Paolucci
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Oliva
authors.forename: Maria
authors.initials: M
authors.lastname: Frigerio
authors.forename: Giovanni
authors.initials: G
authors.lastname: Magenta
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Cattafi
authors.forename: Rita
authors.initials: R
authors.lastname: Vecchi
authors.forename: Ilaria
authors.initials: I
authors.lastname: Vicini
authors.forename: Sergio
authors.initials: S
authors.lastname: Cavaglià
mesh_terms: D002037:Bundle-Branch Block / Q000150:complications; D002304:Cardiac Pacing, Artificial; D009202:Cardiomyopathies / Q000150:complications; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000209:etiology / Q000628:therapy*; D006352:Heart Ventricles; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010138:Pacemaker, Artificial; D018579:Patient Selection; D012189:Retrospective Studies; D016019:Survival Analysis