G. Gaggioli et al., EFFECT OF CHRONIC VASODILATOR THERAPY TO ENHANCE SUSCEPTIBILITY TO VASOVAGAL SYNCOPE DURING UPRIGHT TILT TESTING, The American journal of cardiology, 80(8), 1997, pp. 1092
To evaluate the effect of chronic vasodilator therapy on susceptibilit
y to vasovagal syncope, 45 patients with syncope and a positive respon
se to tilt testing were randomly assigned to continue or to discontinu
e vasodilators, The study result demonstrated that chronic vasodilator
therapy enhances susceptibility to vasovagal reaction during upright
tilt testing.