Rate-dependent changes in atrial action potential duration after short- duration rapid atrial pacing in humans.
The effect of rapid atrial pacing on the rate adaptation of the atrial action potential duration was studied in humans. The right atrial monophasic action potential (RAMAP) of 5 patients was recorded before and after 30 min of rapid atrial pacing. The pacing cycle length (CL) was 146 +/- 9 ms, the shortest duration at which 1:1 capture was possible. The RAMAP duration at 90% repolarization (RMAPD) was measured. CL-dependent changes in RAMAPD (CL 600 ms-CL 300 ms) before and after rapid atrial pacing were 51.8 +/- 10.7 ms and 30.8 +/- 7.6 ms (p < 0.05), respectively.
Watanabe
Ichiro
I
Second Department of Medicine, Nihon University School of Medicine, Tokyo, Japan. iwatanab@med.nihon-u.ac.jp
Masaki
Riko
R
Ohkubo
Kimie
K
Okumura
Yasuo
Y
Yamada
Takeshi
T
Oshikawa
Naohiro
N
Saito
Satoshi
S
Ozawa
Yukio
Y
Kanmatsuse
Katsuo
K
D000200:Action Potentials; D000328:Adult; D001281:Atrial Fibrillation / Q000503:physiopathology* / Q000628:therapy; D002304:Cardiac Pacing, Artificial / Q000379:methods*; D004562:Electrocardiography; D022062:Electrophysiologic Techniques, Cardiac; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged