title: Implantation depth measured by 64-slice computed tomography is associated with permanent pacemaker requirement following transcatheter aortic valve implantation with the Core Valve(®) system.
abstract: Patients undergoing transcatheter aortic valve implantation (TAVI) are at increased risk for post-interventional conduction disturbances leading to pacemaker (PM) implantation. We analyzed the association between implantation depth within the left ventricular outflow tract (LVOT), measured by 64-slice computed tomography (CT), and 'index electrocardiographic (ECG) changes' (new onset atrioventricular-block grade II or III or left bundle branch block with PR interval prolongation >200ms).
  
  
  
  We evaluated patients who underwent TAVI with the Core Valve(®) revalving system (Medtronic, Minneapolis, MN, USA) for treatment of severe aortic stenosis at our department. Patients with a prior PM implantation and patients for whom no CT scan was available after 3 months were excluded from analysis. We assessed implantation depth of the prosthesis within the LVOT as possible risk factors for the development of post-interventional 'index ECG changes' resulting in PM implantation and compared it with individual patient data as well as echocardiographic and electrocardiographic parameters.
  
  
  
  The final study cohort comprised 53 patients for whom a 64-slice CT scan was available (mean age 81.7±5.1 years, 36% male). Twenty-eight of these finally underwent PM implantation due to 'index ECG changes' within the first 48hours after TAVI. Univariate logistic regression analysis could identify implantation depth of the prosthesis as the only significantly correlated risk factor for PM need in our cohort (OR 1.27, 95% CI: 1.08-1.51, p=0.004). A cut-off value of 6mm predicted this need with a sensitivity of 89% and specificity of 40%.
  
  
  
  Implantation depth of the Core Valve(®) into the LVOT was associated with post-procedural PM requirement. Thereby, a cut-off value of 6mm, as measured by 64-slice CT, proved useful to define patients at risk for PM requirement.
authors.affiliation: Linz General Hospital, 1st Medical Department - Cardiology, Johannes Kepler University School of Medicine, Linz, Austria. Electronic address: juergen.kammler@akh.linz.at.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Kammler
authors.affiliation: Linz General Hospital, 1st Medical Department - Cardiology, Johannes Kepler University School of Medicine, Linz, Austria.
authors.forename: Hermann
authors.initials: H
authors.lastname: Blessberger
authors.affiliation: Linz General Hospital, Department of Radiology, Johannes Kepler University School of Medicine, Linz, Austria.
authors.forename: Franz
authors.initials: F
authors.lastname: Fellner
authors.affiliation: Linz General Hospital, 1st Medical Department - Cardiology, Johannes Kepler University School of Medicine, Linz, Austria.
authors.forename: Alexander
authors.initials: A
authors.lastname: Kypta
authors.affiliation: Linz General Hospital, 1st Medical Department - Cardiology, Johannes Kepler University School of Medicine, Linz, Austria.
authors.forename: Thomas
authors.initials: T
authors.lastname: Lambert
authors.affiliation: Linz General Hospital, 1st Medical Department - Cardiology, Johannes Kepler University School of Medicine, Linz, Austria.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Engl
authors.affiliation: Linz General Hospital, 1st Medical Department - Cardiology, Johannes Kepler University School of Medicine, Linz, Austria.
authors.forename: Simon
authors.initials: S
authors.lastname: Hönig
authors.affiliation: Department of Cardiology, Clinic of Internal Medicine II, Paracelsus Medical University of Salzburg, Austria.
authors.forename: Michael
authors.initials: M
authors.lastname: Lichtenauer
authors.affiliation: Linz General Hospital, 1st Medical Department - Cardiology, Johannes Kepler University School of Medicine, Linz, Austria.
authors.forename: Michael
authors.initials: M
authors.lastname: Grund
authors.affiliation: Linz General Hospital, 1st Medical Department - Cardiology, Johannes Kepler University School of Medicine, Linz, Austria.
authors.forename: Klaus
authors.initials: K
authors.lastname: Kerschner
authors.affiliation: Linz General Hospital, 1st Medical Department - Cardiology, Johannes Kepler University School of Medicine, Linz, Austria.
authors.forename: Karim
authors.initials: K
authors.lastname: Saleh
authors.affiliation: Linz General Hospital, 1st Medical Department - Cardiology, Johannes Kepler University School of Medicine, Linz, Austria.
authors.forename: Clemens
authors.initials: C
authors.lastname: Steinwender
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001024:Aortic Valve Stenosis / Q000000981:diagnostic imaging* / Q000601:surgery; D001145:Arrhythmias, Cardiac / Q000209:etiology / Q000601:surgery*; D015331:Cohort Studies; D003131:Combined Modality Therapy; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D061330:Multidetector Computed Tomography; D010138:Pacemaker, Artificial; D012016:Reference Values; D012307:Risk Factors; D013997:Time Factors; D065467:Transcatheter Aortic Valve Replacement / Q000009:adverse effects* / Q000295:instrumentation / Q000379:methods; D016896:Treatment Outcome
keywords: 64-slice computed tomography; Aortic valve stenosis; Pacemaker requirement; Transcatheter aortic valve implantation