Effect of timolol on exercise-induced reduction in regional ejection fraction in patients with coronary artery disease.

In order to evaluate the effects of timolol, a new beta-adrenergic blocking agent, on exercise-induced left ventricular wall motion abnormalities, we studied nine patients with chronic, angiographically-documented coronary artery disease. A computerized technique for determining apical, anteroseptal and inferoposterior regional ejection fractions during gated radionuclide ventriculography was used to assess left ventricular dysfunction. During exercise prior to the administration of timolol, the apical regional ejection fraction fell from 0.62 +/- 0.08 to 0.51 +/- 0.08 (p less than .01). The anteroseptal ejection fraction fell from 0.50 +/- 0.08 to 0.41 +/- 0.05 (p less than .05), and the inferoposterior ejection fraction fell from 0.75 +/- 0.10 to 0.59 +/- 0.06 (p less than .05). Three days after beginning therapy with 10-30 mg of timolol, this reduction was markedly attenuated. The apical ejection fraction fell from 0.59 +/- 0.09 to 0.54 +/- 0.08 (p = NS), the anteroseptal ejection fraction fell from 0.49 +/- 0.07 to 0.47 +/- 0.18 (p = NS) and the inferoposterior ejection fraction fell from 0.62 +/- 0.06 to 0.59 +/- 0.07 (p = NS). Furthermore, several individual regions showed increases in ejection fraction. This study demonstrates a previously unreported and beneficial anti-ischemic effect of timolol.