title: Monophasic action potential duration at the crista terminalis in patients with sinus node disease.
abstract: BACKGROUND
  The repolarization properties of the crista terminalis (CT) cells have not been elucidated in patients with sinus node disease (SND). In the present study a new technique of recording the monophasic action potential (MAP) at the CT was used to examine the repolarization of the right atrium (RA) in SND patients.
  
  
  RESULTS
  Symptomatic SND (n=13) patients and age-, sex-matched control patients (n=13) were tested. The MAP duration (MAPD) at a basic cycle length of 600 ms was recorded at the CT in the superior vena cava - RA junction and at the middle - anterior RA with the effective refractory period (ERP) at the high RA. In 6 controls and 4 SND patients, the effect of adenosine triphosphate on the MAPD was examined. The MAPD at the CT exceeded that at the middle - anterior RA in both groups. The MAPD at the CT in the SND group was significantly prolonged compared with the control group (CT: 358+/-39 ms vs 289+/-43 ms). Between the SND and control groups, the MAPD at the middle - anterior RA (278+/-36 ms vs 265+/-39 ms) and ERP (294+/-42 ms vs 266+/-41 ms) did not differ. Both the corrected-sinus node recovery time and sinoatrial conduction time were better correlated with the MAPD at the CT than the MAPD at the middle - anterior RA and ERP. Adenosine triphosphate shortened the MAPD, which was augmented at the CT in the SND patients.
  
  
  CONCLUSIONS
  A novel method of estimating the MAP at the CT revealed the characteristics of atrial repolarization in SND patients.
authors.affiliation: Department of Cardiovascular Medicine, Tohoku Rosai Hospital, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Katoh
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Shinozaki
authors.forename: Shigeo
authors.initials: S
authors.lastname: Baba
authors.forename: Shoichi
authors.initials: S
authors.lastname: Satoh
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Kagaya
authors.forename: Jun
authors.initials: J
authors.lastname: Watanabe
authors.forename: Kunio
authors.initials: K
authors.lastname: Shirato
mesh_terms: D000200:Action Potentials; D000219:Adams-Stokes Syndrome / Q000503:physiopathology*; D000368:Aged; D002303:Cardiac Output, Low / Q000503:physiopathology*; D022062:Electrophysiologic Techniques, Cardiac / Q000379:methods; D005260:Female; D006325:Heart Atria / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D012849:Sinoatrial Node / Q000503:physiopathology*