title: High Incidence of Dilated Cardiomyopathy After Right Ventricular Inlet Pacing in Patients With Congenital Complete Atrioventricular Block.
abstract: BACKGROUND
  Some patients with congenital complete atrioventricular block (CCAVB) develop dilated cardiomyopathy (DCM) after pacemaker implantation (PMI). We evaluated the relationship between pacing site and DCM incidence.
  
  
  RESULTS
  We retrospectively evaluated 38 patients with CCAVB; 8 (25%) of 32 patients who had PMI developed DCM/heart failure death (HFD) after PMI, although none of the 6 patients without PMI showed DCM/HFD. All DCM/HFD occurred within 50 months of PMI. Among the 32 patients with PMI, the DCM/HFD incidence was 55% (6/11) for right ventricular inlet (RVI), 18% (2/11) for RV apex (RVA), and 0% for left ventricle (LV) (P=0.013). At the endpoint, the LV ejection fraction and septal-to-posterior wall motion delay of patients with LV pacing were better than those for patients with other pacing sites. Among the 8 DCM/HFD patients, 2 in whom the pacing site was changed from RVI to LV apex or in whom therapy was upgraded to cardiac resynchronization remained alive with no heart failure symptoms, whereas the other 6 died of heart failure.
  
  
  CONCLUSIONS
  A total of 25% of the patients who underwent PMI because of CCAVB, but none in the non-PMI group, developed DCM/HFD. DCM/HFD incidence was higher in patients with RVI pacing. Ventricular dyssynchrony related to pacing site may be one cause of DCM in patients with CCAVB. (Circ J 2016; 80: 1251-1258).
authors.affiliation: Department of Pediatric Cardiology, National Cerebral and Cardiovascular Center.
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Tsujii
authors.forename: Aya
authors.initials: A
authors.lastname: Miyazaki
authors.forename: Heima
authors.initials: H
authors.lastname: Sakaguchi
authors.forename: Koji
authors.initials: K
authors.lastname: Kagisaki
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Yamamoto
authors.forename: Michio
authors.initials: M
authors.lastname: Matsuoka
authors.forename: Yuriko
authors.initials: Y
authors.lastname: Shima
authors.forename: Hajime
authors.initials: H
authors.lastname: Ichikawa
authors.forename: Hideo
authors.initials: H
authors.lastname: Ohuchi
mesh_terms: D054537:Atrioventricular Block / Q000150:complications* / Q000151:congenital / Q000601:surgery; D002304:Cardiac Pacing, Artificial / Q000009:adverse effects* / Q000379:methods; D002311:Cardiomyopathy, Dilated / Q000209:etiology* / Q000401:mortality; D006333:Heart Failure / Q000209:etiology / Q000401:mortality; D006352:Heart Ventricles / Q000503:physiopathology; D006801:Humans; D015994:Incidence; D012189:Retrospective Studies