title: The clinical course and incidence of supraventricular tachyarrhythmias after extra-cardiac conduit Fontan procedures in relation to an atrial situs.
abstract: BACKGROUND
  The extra-cardiac conduit Fontan (EC) has a lower incidence of tachyarrhythmias than other types of Fontan. However, some intrinsic arrhythmogenic conditions, such as atrial isomerism, have been associated with a high incidence of arrhythmias.
  
  
  RESULTS
  We retrospectively reviewed the clinical course of the supraventricular tachyarrhythmias (SVTs) in 212 patients after an EC, compared the results according to the atrial situs and investigated the substrate of the SVTs. The atrial situs was a solitus or inversus (SS/SI) in 152 patients, right isomerism (RI) in 45 and left isomerism (LI) in 15. Twenty-four SVTs occurred in 22 (11%) patients ≥3 months after the EC. The freedom from SVT after the EC was 95%, 76% and 77% in the SS/SI, RI and LI patients at 5 years, respectively (P<0.0001). Among the 16 SVTs associated with atrial isomerism, 10 were not related to the atrioventricular (AV) node. For the atrial isomerism, the predictors of SVT ≥3 months after the EC were a history of an AV valve repair (risk ratio (RR) 1.9; P=0.02) and complications associated with sinus node dysfunction (RR 1.9; P=0.03). Death related to SVT occurred in 3 patients.
  
  
  CONCLUSIONS
  Postoperative SVTs after the EC with an atrial isomerism were not uncommon, mostly did not involve the AV node and possibly were caused by atrial tissue damage. A comprehensive therapeutic strategy should be considered.
authors.affiliation: Department of Pediatric Cardiology, National Cerebral and Cardiovascular Center, Suita, Japan. ayamiya@hsp.ncvc.go.jp
authors.forename: Aya
authors.initials: A
authors.lastname: Miyazaki
authors.forename: Heima
authors.initials: H
authors.lastname: Sakaguchi
authors.forename: Hideo
authors.initials: H
authors.lastname: Ohuchi
authors.forename: Osamu
authors.initials: O
authors.lastname: Yamada
authors.forename: Masataka
authors.initials: M
authors.lastname: Kitano
authors.forename: Satoshi
authors.initials: S
authors.lastname: Yazaki
authors.forename: Hisashi
authors.initials: H
authors.lastname: Sugiyama
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Kurosaki
authors.forename: Koji
authors.initials: K
authors.lastname: Kagisaki
authors.forename: Toshikatsu
authors.initials: T
authors.lastname: Yagihara
authors.forename: Etsuko
authors.initials: E
authors.lastname: Tsuda
mesh_terms: D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D018729:Fontan Procedure / Q000379:methods*; D006325:Heart Atria / Q000002:abnormalities*; D006801:Humans; D015994:Incidence; D007223:Infant; D053208:Kaplan-Meier Estimate; D008297:Male; D011183:Postoperative Complications / Q000453:epidemiology* / Q000209:etiology; D012189:Retrospective Studies; D012857:Situs Inversus / Q000150:complications*; D013617:Tachycardia, Supraventricular / Q000453:epidemiology* / Q000209:etiology / Q000401:mortality