Vasovagal response induced by a low dose of isoproterenol infusion before tilting-up.
A 56 year-old man was referred to hospital for evaluation of syncopal episodes. During head-up tilt testing, his symptom was reproduced, associated with bradycardia and hypotension, by a low dose of isoproterenol (0.02 microg. kg (-1). min(-1)) infusion in the supine position before tilting-up. Isoproterenol infusion can provoke a vasovagal response without tilting. Careful observation of the patient's hemodynamics is mandatory not only during tilting, but also in the supine position before tilting-up.
Department of Cardiology, Juntendo University Izunagaoka Hospital, Shizuoka, Japan.
Satoru
S
Suwa
Masataka
M
Sumiyoshi
Yoriaki
Y
Mineda
Hiroshi
H
Ohta
Satoshi
S
Kojima
Yasuro
Y
Nakata
D006439:Hemodynamics / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D007262:Infusions, Intravenous; D007545:Isoproterenol / Q000008:administration & dosage / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D019462:Syncope, Vasovagal / Q000139:chemically induced*; D018667:Tilt-Table Test / Q000009:adverse effects*
D007545:Isoproterenol