title: Cardiac resynchronization therapy: predictive factors of unsuccessful left ventricular lead implant.
abstract: OBJECTIVE
  Cardiac resynchronization therapy is an established therapy for advanced heart failure. However, coronary sinus access and pacing is not achieved in about 5-10% of patients. The aim of this study was to identify predictive factors for failure of left ventricular (LV) lead transvenous implant.
  
  
  RESULTS
  We evaluated 212 consecutive patients who received a cardiac resynchronization system. In 26 patients (12.3%), the attempt to pace the LV was unsuccessful. At univariate analysis, in patients with an unsuccessful implant a higher proportion of permanent atrial fibrillation (AF), valvular heart disease, and previous heart surgery were observed. Anteroposterior, longitudinal, and transversal left atrium diameters (LAD) were also larger among patients with an unsuccessful implant. The anteroposterior LAD (APLAD) with an optimal value to predict implant failure was 48.5 mm. At logistic regression analysis, the presence of permanent AF and APLAD were independent predictors of failed implant (OR 7.7, 95% CI 2.5-23.9, P=0.002 and OR 11.7, 95% CI 3.1-37.6, P<0.001, respectively).
  
  
  CONCLUSIONS
  The presence of permanent AF and APLAD are factors that predict unsuccessful pacing from the LV.
authors.affiliation: Thorax Institute, Hospital Clinic Universitari de Barcelona, Institut d'Investigació Biomèdica August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
authors.forename: Alfonso
authors.initials: A
authors.lastname: Macías
authors.forename: Ignacio
authors.initials: I
authors.lastname: García-Bolao
authors.forename: Ernesto
authors.initials: E
authors.lastname: Díaz-Infante
authors.forename: Jose María
authors.initials: JM
authors.lastname: Tolosana
authors.forename: Bárbara
authors.initials: B
authors.lastname: Vidal
authors.forename: Juan José
authors.initials: JJ
authors.lastname: Gavira
authors.forename: Antonio
authors.initials: A
authors.lastname: Berruezo
authors.forename: Josep
authors.initials: J
authors.lastname: Brugada
authors.forename: Lluis
authors.initials: L
authors.lastname: Mont
mesh_terms: D000368:Aged; D001281:Atrial Fibrillation / Q000000981:diagnostic imaging / Q000628:therapy*; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D017147:Defibrillators, Implantable / Q000592:standards*; D004452:Echocardiography; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D010138:Pacemaker, Artificial; D012680:Sensitivity and Specificity; D017211:Treatment Failure