[en] The gamma-angio-cardiography at equilibrium is the reference method for the calculation of the left ventricular function (FEVG). We have studied the percentage of centro-cavitary activity (PCCA) by myocardium tomo-scintigraphy. The PCCA was calculated on the basis of the measurement of activity at the center of left ventricular cavity (C) of a small-axis medial cross section, divided to myocardium maximal activity (M_max): PCCA (C/M_max) x 100. The obtained values were compared with that of isotopic FEVG in 251 consecutive patients who benefited both by a Tl-201 tomo-scintigraphy (stress/redistribution) and a gamma-angio-cardiography at equilibrium. The correlation between PCCA and FEVG was: r = 0.82 (y = 0.75 x + 1.69; P 0.0001). The PCCA is easily obtainable on the basis of Tl - 201 myocardial tomo-scintigraphies and allows a rapid evaluation of the global left ventricular function