NONINVASIVE ASSESSMENT OF CARDIAC PHYSIOLOGY BY TISSUE DOPPLER-ECHOCARDIOGRAPHY - A COMPARISON WITH INVASIVE HEMODYNAMICS

Background Tissue Doppler echocardiography reveals characteristic patt erns of myocardial velocities within systole and diastole which are no t well understood. Aim The purpose of this study was to determine the relationship of myocardial velocity patterns, as assessed by tissue Do ppler echocardiography, to the contraction and relaxation phases of th e cardiac cycle, as determined during cardiac catheterization. Methods Recordings of left ventricular/aortic and left ventricular/pulmonary wedge pressures were obtained simultaneously with apical tissue Dopple r echocardiographic images of the left ventricle. A total of 210 cardi ac cycles from 22 patients (mean age 58 years, 18 male) undergoing car diac catheterization were analysed. The time intervals of the differen t phases of the cardiac cycle were measured from the pressure tracings . These time intervals were correlated to the interfaces of colour myo cardial velocity patterns obtained by M-mode tissue Doppler echocardio graphy. Results There was a good correlation between the time interval s assessed haemodynamically and those based on the different velocity interfaces obtained with M-mode tissue Doppler echocardiography. Compa rable time inter vals (from the R wave) obtained by pressure recording s and tissue Doppler echocardiography were, respectively: isovolumic c ontraction (7O +/- 14 vs 67 +/- 9 ms, r=0.79); rapid ejection (206 +/- 54 vs 202 +/- 49 ms; r=0.95); late ejection (357 +/- 36 vs 346 +/- 42 ms, r=0.93); isovolumic relaxation (405 +/- 43 vs 409 +/- 56 ms r=0.9 5); rapid filling (514 +/- 67 vs 523 +/- 64 ms, r=0.91); diastasis (69 7 +/- 153 vs 709 +/- 146 ms, r=0.98); atrial contraction (890 +/- 128 vs 899 +/- 132ms, r=0.96). Conclusion Tissue Doppler echocardiography has the potential to accurately measure the different phases of the ca rdiac cycle which until now could only be determined invasively. It ma y provide a sensitive method for the assessment of changes in both car diac contraction and relaxation in different clinical settings.