[Detection of ventricular asynchrony using tissue Doppler echocardiography--a new method for assessing left ventricular wall motion].

UNLABELLED

The asynchrony of the heart in patients with coronary artery disease can be detected by digitized cine- and radionuclidventriculography. Both methods require time-consuming offline analysis. The aim of the current study was the assessment of the clinical value of the recently developed tissue Doppler echocardiography (TDE) to detect myocardial asynchrony. In the current study, 21 healthy subjects (age 49 +/- 14 y) and 22 patients with known coronary artery disease (20 with > 70% luminal narrowing of the LAD, 4 with a history of CABG, age 58 +/- 12 y) were included. In the apical 4-chamber-view, midseptal and midlateral LV segments were analyzed by 2-D and M-Mode-TDE. Evaluation was possible in 20 healthy subjects (95%) and 20 CAD patients (91%). During isovolumic relaxation time (IVRT) healthy subjects showed slow synchronous outward motion of the septum and the free wall with homogenous color coding (blue/green) and low negative tissue velocities followed by rapid symmetrical outward motion during rapid filling (RF) and atrial contraction (AC) phase (high negative velocities). During diatasis (DI) almost no wall motion could be detected. In 17 (85%) of 20 CAD patients, myocardial asynchrony during IVRT was detected; while the septum was moving inward (red coding with low positive velocities), the free wall was moving outward (blue green coding with low negative/velocities). After opening of the mitral valve, all CAD patients showed rapid, symmetrical outward motion of both the septum and the free wall with homogenous color coding and high negative tissue velocities.

CONCLUSION

Tissue Doppler echocardiography detects ventricular asynchrony online. In patients with significant LAD stenosis, a pathological septal movement is observed during isovolumic relaxation time. Determinants of the etiology could be chronic hypoperfusion or ischemia ("hibernating myocardium").