Exercise induced atrioventricular block with gap phenomenon in atrioventricular conduction.
A 54-year-old man with normal atrioventricular (AV) conduction at rest gave a 4-year history of presyncope during exercise. Treadmill testing showed exercise induced AV block. Electrophysiological study demonstrated rate dependent infranodal AV block and abnormal refractory period of the His-Purkinje system. The gap phenomenon in AV conduction occurred during the programmed stimulation. Supernormal conduction could be considered as the mechanism of the gap phenomenon in this patient.
Toeda
T
T
Department of Cardiology, Niigata City General Hospital, Japan.
Suetake
S
S
Tsuchida
K
K
Takahashi
K
K
Miida
T
T
Oda
H
H
Higuma
N
N
D001283:Atrioventricular Node / Q000503:physiopathology*; D002036:Bundle of His / Q000503:physiopathology; D002304:Cardiac Pacing, Artificial; D004562:Electrocardiography; D005080:Exercise Test / Q000009:adverse effects*; D006327:Heart Block / Q000209:etiology* / Q000503:physiopathology / Q000628:therapy; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged