A comparison of bioimpedance and echocardiography in measuring systolic heart function in cardiac patients.

To investigate the ability of bioimpedance cardiography to assess left ventricular systolic function in comparison with known echocardiographic parameters and to establish the most informative bioimpedance parameter, 28 cardiac patients were submitted to simultaneous echocardiography and bioimpedance cardiography. Bioimpedance systolic time ratio, Heather index, acceleration index, and index of contractility were compared with echocardiographically obtained left ventricular dimensions, 2D left ventricular ejection fraction, fractional shortening, and mean velocity of circumferential shortening. The systolic time ratio and Heather index correlated significantly well with, respectively, 2D ejection fraction (r = -0.73) and, respectively, fractional shortening (r = 0.69). The systolic time ratio was the best parameter in recognizing impaired left ventricular systolic function (F = 12.6) in comparison with the Heather index (F = 6.5). This study demonstrates the applicability of bioimpedance cardiography in assessing left ventricular systolic function similar to echocardiography in clinical cardiology.