Short-term anti-ischemic effect of 17beta-estradiol in postmenopausal women with coronary artery disease.
BACKGROUND
Short-term administration of 17beta-estradiol improves effort-induced myocardial ischemia in female patients with coronary artery disease. 17Beta-estradiol also has direct and indirect coronary vascular smooth muscle relaxing properties. The aim of the present study was to evaluate the effect of short-term administration of 17beta-estradiol on pacing-induced myocardial ischemia by means of continuous monitoring of coronary sinus pH in 16 postmenopausal female patients with coronary artery disease.


RESULTS
Patients underwent incremental atrial pacing starting at a rate of 100 bpm and increments of 20 bpm every 2 minutes up to 160 bpm before and 20 minutes after either 17beta-estradiol (1 mg sublingual, 9 patients) or placebo (sublingual, 7 patients). The time to the onset of myocardial ischemia during pacing was significantly increased by 17beta-estradiol (mean+/-SD, 254+/-36 versus 298+/-23 seconds; P<.02) but not by placebo (262+/-45 versus 256+/-34 seconds; P=NS) The pH shift was significantly reduced by 17beta-estradiol but not by placebo at every step of the pacing protocol. The maximum pH shift at peak pacing was significantly reduced by the administration of 17beta-estradiol by 0.022 pH units (95% CI, 0.001, 0.043; P<.04) but not by sublingual placebo (-0.002 pH units; 95% CI, -0.0073, 0.0021; P=NS). The maximum pH shift at maximum comparable pacing was also reduced by 17beta-estradiol by 0.015 pH units (95% CI, 0.012, 0.017; P<.001) but not by placebo (-0.0022 pH units; 95% CI, -0.006, 0.0015; P=NS).


CONCLUSIONS
17Beta-estradiol reduces the degree of pacing-induced myocardial ischemia in postmenopausal patients with coronary artery disease. The reduction of pacing-induced coronary sinus pH shift is consistent with an anti-ischemic effect of the hormone and is not due to preconditioning, as evidenced by the absence of improvement after placebo.
Rosano
G M
GM
Istituto H San Raffaele, Roma/Milan, Italy.
Caixeta
A M
AM
Chierchia
S
S
Arie
S
S
Lopez-Hidalgo
M
M
Pereira
W I
WI
Leonardo
F
F
Webb
C M
CM
Pileggi
F
F
Collins
P
P
D002304:Cardiac Pacing, Artificial; D003327:Coronary Disease / Q000188:drug therapy*; D004958:Estradiol / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000517:prevention & control*; D017698:Postmenopause
D004958:Estradiol