[Atenolol induced bradycardia in patients with stable angina: effects on exercise tolerance, myocardial perfusion and left ventricular contractility].
OBJECTIVE
To assess effects of atenolol-induced heart rate decrease on myocardial perfusion, left ventricular contractility and tolerance to exercise in patients with chronic coronary artery disease.


METHODS
Twenty eight men (mean age 54,5-/+9,2 years) with stable class I-III angina and positive reproducible result of bicycle exercise test underwent rest/stress 99mTc-MIIBI gated single-photon emission computed tomography (SPECT) before and after 10 days of administration of atenolol (20 patients) or placebo (8 patients). Dose of atenolol was titrated to achieve at least 15% decrease of heart rate from baseline.


RESULTS
After 10 days of treatment with atenolol heart rate decreased from 78-/+3.1 to 59-/+1.1 bpm (p=0.01), whereas in placebo group there were no significant changes. Compared with placebo, treatment with atenolol was associated with significant decreases in extent and severity of perfusion defects, ischemic score and number of ischemic segments. No significant changes of parameters of left ventricular contractility occurred. Treatment with atenolol was associated with symptomatic improvement and increase of the total exercise time.


CONCLUSIONS
Heart rate lowering during monotherapy with atenolol was associated with improvement of myocardial perfusion and tolerance to exercise.
Safonova
E V
EV
Zharova
E A
EA
Samoĭlenko
L E
LE
Sergienko
V B
VB
D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage*; D000787:Angina Pectoris / Q000188:drug therapy* / Q000503:physiopathology*; D001262:Atenolol / Q000008:administration & dosage*; D003326:Coronary Circulation / Q000502:physiology; D017079:Exercise Tolerance / Q000502:physiology; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction / Q000502:physiology; D011877:Radionuclide Imaging; D016277:Ventricular Function, Left / Q000502:physiology
D000319:Adrenergic beta-Antagonists; D001262:Atenolol