Hemodynamic long-term effects of timolol at rest and during exercise in essential hypertension.

Sixteen men with previously untreated essential hypertension in WHO stage I have been studied as out-patients. Oxygen consumption, heart rate (HR), cardiac output (Q) (Cardiogreen) and intraarterial brachial pressure were recorded at rest in supine and sitting position and during steady state work at 300, 600 and 900 kpm/min. The subjects were treated with timolol as the sole drug for one year and the hemodynamic study was repeated. BP was reduced approximately 18% at rest and 14% during exercise, HR approximately 26% and the cardiac index 28% at rest supine and 32% at rest sitting. During exercise the reductions in Q were 25-30%. The calculated total peripheral resistance was significantly increased at rest as well as during exercise. The product of mean arterial pressure and HR was reduced about 40%. No severe side-effects were seen.