In recent years many indices have been studied to evaluate myocardial inotropic state, applying the skeletal muscle mechanics to intact heart. Among such indices, V_max(maximum velocity of shortening of the unloaded contractile elements) and V_pm(physiologic maximum observed velocity of myocardial shortening) provide a measure of myocardial contractility independent of preload or afterload.

To obtain normal values in Korean adults, the left ventricular pressure data of 16 patients with normal physical activities were analyzed, using the digital computer.

Seven patients had ventricular septal defect with Qp/Qs less than 2.0, one patient had mitral stenosis, another one patient had mitral stenosis and aortic regurgitation (grade I/IV and the remainder seven patients had no intrinsic cardiac disorder. But, the cardiac performances of all patients were apparently normal.

The results were as follows:

1) Cardiac index was greater than 3.0 l/min/m² in all patinets: 4.9±1.32(±S.D.)l.min/m².

2) Ejection fraction was greater than 55% in all patients: 71.2±8.04(±S.D.)%.

3) Left ventricular end diastolic pressure(LVEDP) ranged from 3 mmHg to 12 mmHg.

4) V_max: 48.1±9.41(±S.D.) sec^-1.

5) V_pm: 39.3±8.13(±S.D.) sec^-1.