title: Factors predicting and having an impact on the need for a permanent pacemaker after CoreValve prosthesis implantation using the new Accutrak delivery catheter system.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the need for a permanent pacemaker after transcatheter aortic valve implantation with the CoreValve prosthesis (Medtronic, Inc., Minneapolis, Minnesota) using the new Accutrak delivery system (Medtronic, Inc.).
  
  
  BACKGROUND
  The need for a permanent pacemaker is a recognized complication after transcatheter aortic valve implantation with the CoreValve prosthesis.
  
  
  METHODS
  Between April 23, 2008 and May 31, 2011, 195 consecutive patients with symptomatic aortic valve stenosis underwent transcatheter aortic valve implantation using the self-expanding CoreValve prosthesis. In 124 patients, the traditional delivery system was used, and in 71 patients, the Accutrak delivery system was used.
  
  
  RESULTS
  There were no significant differences in baseline electrocardiographic characteristics between the traditional system and the Accutrak patients: PR interval: 153 ± 46 mm versus 165 ± 30 mm, p = 0.12; left bundle branch block: 22 (20.2%) versus 8 (12.7%), p = 0.21; right bundle branch block: 21 (19.3%) versus 8 (12.7%), p = 0.26. The depth of the prosthesis in the left ventricular outflow tract was greater with the traditional system than with the Accutrak system (9.6 ± 3.2 mm vs. 6.4 ± 3 mm, p < 0.001) and the need for a permanent pacemaker was higher with traditional system than with Accutrak (35.1% vs. 14.3%, p = 0.003). The predictors of the need for a pacemaker were the depth of the prosthesis in the left ventricular outflow tract (hazard ratio [HR]: 1.2, 95% confidence interval [CI]: 1.08 to 1.34, p < 0.001), pre-existing right bundle branch block (HR: 3.5, 95% CI: 1.68 to 7.29, p = 0.001), and use of the traditional system (HR: 27, 95% CI: 2.81 to 257, p = 0.004).
  
  
  CONCLUSIONS
  The new Accutrak delivery system was associated with less deep prosthesis implantation in the left ventricular outflow tract, which could be related to the lower rate of permanent pacemaker requirement.
authors.affiliation: Department of Cardiology, Virgen de la Victoria Clinical University Hospital, Malaga, Spain. Electronic address: ajmunozgarcia@secardiologia.es.
authors.forename: Antonio J
authors.initials: AJ
authors.lastname: Muñoz-García
authors.affiliation: Department of Cardiology, Virgen de la Victoria Clinical University Hospital, Malaga, Spain.
authors.forename: José M
authors.initials: JM
authors.lastname: Hernández-García
authors.affiliation: Department of Cardiology, Virgen de la Victoria Clinical University Hospital, Malaga, Spain.
authors.forename: Manuel F
authors.initials: MF
authors.lastname: Jiménez-Navarro
authors.affiliation: Department of Cardiology, Virgen de la Victoria Clinical University Hospital, Malaga, Spain.
authors.forename: Juan H
authors.initials: JH
authors.lastname: Alonso-Briales
authors.affiliation: Department of Cardiology, Virgen de la Victoria Clinical University Hospital, Malaga, Spain.
authors.forename: Antonio J
authors.initials: AJ
authors.lastname: Domínguez-Franco
authors.affiliation: Department of Cardiology, Virgen de la Victoria Clinical University Hospital, Malaga, Spain.
authors.forename: Julia
authors.initials: J
authors.lastname: Fernández-Pastor
authors.affiliation: Department of Cardiology, Virgen de la Victoria Clinical University Hospital, Malaga, Spain.
authors.forename: Jose
authors.initials: J
authors.lastname: Peña Hernández
authors.affiliation: Department of Cardiology, Virgen de la Victoria Clinical University Hospital, Malaga, Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: Barrera Cordero
authors.affiliation: Department of Cardiology, Virgen de la Victoria Clinical University Hospital, Malaga, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: Alzueta Rodríguez
authors.affiliation: Department of Cardiology, Virgen de la Victoria Clinical University Hospital, Malaga, Spain.
authors.forename: Eduardo
authors.initials: E
authors.lastname: de Teresa-Galván
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001024:Aortic Valve Stenosis / Q000175:diagnosis / Q000628:therapy*; D002037:Bundle-Branch Block / Q000175:diagnosis / Q000209:etiology / Q000628:therapy*; D006328:Cardiac Catheterization / Q000009:adverse effects / Q000295:instrumentation*; D002304:Cardiac Pacing, Artificial; D057785:Catheters; D016009:Chi-Square Distribution; D004562:Electrocardiography; D004867:Equipment Design; D005260:Female; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation*; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D010138:Pacemaker, Artificial; D016016:Proportional Hazards Models; D011474:Prosthesis Design; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D013030:Spain; D013997:Time Factors; D016896:Treatment Outcome