title: Surface and intracardiac ECG for discriminating conduction disorders after CoreValve implantation.
abstract: BACKGROUND
  Transcatheter aortic valve implantation (TAVI) has been developed to minimize operative morbidity and mortality in high-risk symptomatic patients unfit for open surgery. With the proximity of the aortic valve annulus to the conduction system there is, however, an unknown risk of conduction disturbances necessitating monitoring and often cardiac pacing.
  
  
  METHODS
  We enrolled 50 consecutive patients from January 2007 to 2008 in our prospective evaluation of conduction disturbances measured by surface and intracardiac ECG recordings. Baseline parameters, procedural characteristics as well as twelve-lead surface ECG and intracardiac conduction times were revealed pre-interventionally, after TAVI and at 7-day follow-up.
  
  
  RESULTS
  TAVI was performed successfully in all patients. During 7 days of follow-up the rate for first-degree AV block raised from 14% at baseline to 44% at day 7 (p < 0.001), while rates for type II second- and third-degree were 0 versus 8% (p < 0.001) and 0 versus 12% (p < 0.001), respectively. Similarly, the prevalence of new left bundle branch block (LBBB) rose from 2 to 54% (p < 0.001). Intracardiac measurements revealed a prolongation of both AH and HV interval from 123.7 ± 41.6 to 136.6 ± 40.5 ms (p < 0.001) and from 54.8 ± 11.7 to 71.4 ± 20.0 ms (p < 0.001), respectively. Pacemaker implantation at a mean follow-up of 4.8 ± 1.2 days was subsequently performed in 23 patients (46%) due to complete AV block (12%) and type II second-degree AV block (8%) while another 13 patients (26%) received a pacemaker for the combination of new LBBB with marked HV prolongation. The high rate of first-degree AV block was primarily driven by an increase in HV interval.
  
  
  CONCLUSIONS
  Cardiac conduction disturbances were common in the early experience with CoreValve implantation necessitating close surveillance for at least 1 week.
authors.affiliation: Heart Center Rostock, Department of Internal Medicine I, Rostock School of Medicine, University Hospital Rostock, Rostock, Germany.
authors.forename: I
authors.initials: I
authors.lastname: Akin
authors.forename: S
authors.initials: S
authors.lastname: Kische
authors.forename: H
authors.initials: H
authors.lastname: Schneider
authors.forename: A
authors.initials: A
authors.lastname: Liebold
authors.forename: J
authors.initials: J
authors.lastname: Ortak
authors.forename: D
authors.initials: D
authors.lastname: Bänsch
authors.forename: T C
authors.initials: TC
authors.lastname: Rehders
authors.forename: O
authors.initials: O
authors.lastname: Thiele
authors.forename: R
authors.initials: R
authors.lastname: Schneider
authors.forename: G
authors.initials: G
authors.lastname: Kundt
authors.forename: H
authors.initials: H
authors.lastname: Krenz
authors.forename: T
authors.initials: T
authors.lastname: Chatterjee
authors.forename: C A
authors.initials: CA
authors.lastname: Nienaber
authors.forename: H
authors.initials: H
authors.lastname: Ince
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001021:Aortic Valve / Q000601:surgery*; D054537:Atrioventricular Block / Q000175:diagnosis* / Q000209:etiology; D002037:Bundle-Branch Block / Q000175:diagnosis* / Q000209:etiology; D006328:Cardiac Catheterization; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D019918:Heart Valve Prosthesis Implantation; D006801:Humans; D008297:Male; D010138:Pacemaker, Artificial; D011183:Postoperative Complications / Q000175:diagnosis*; D011446:Prospective Studies; D011474:Prosthesis Design