Myocardial Doppler at rest for the identification of myocardial viability.

BACKGROUND

Echocardiography may permit the detection of a nonviable myocardium. The aim of this study was to test if resting pulsed wave-tissue Doppler imaging (PW-TDI) might yield additional markers.

METHODS

Fifty patients (38 males, 12 females, mean age 63 +/- 6 years) with left ventricular dysfunction (ejection fraction 35 +/- 10%) underwent echocardiography. The posterior septum, anterior septum, lateral, inferior, anterior and posterior walls were sampled on the basal segments in the apical views at PW-TDI. The following variables and cardiac phases were tested: 1) the isovolumic contraction phase velocity, polarity or detectability, 2) the ejection phase velocity, a detectable interval between the ejection phase and aortic valve closure, or ejection phase shape, and 3) the isovolumic relaxation phase velocity or ejection velocity/post-systolic shortening ratio. From the tested PW-TDI variables, viable and nonviable patterns were assembled, taking rest-redistribution 201thallium single-photon emission computed tomography as the independent reference for myocardial viability. Patients with significant loading alterations, mitral or aortic valve disease, and arrhythmias were excluded.

RESULTS

Out of 219 dyssynergic segments, viability as identified according to conventional rest echocardiographic criteria appeared in 94 (47%), as identified at PW-TDI in 116 (53%), and as identified at nuclear imaging in 105 (48%). The resting PW-TDI variables consistent with absent myocardial viability were as follows: 1) an isovolumic contraction phase velocity equal to the ejection phase velocity +/- 1 cm/s, or absent, 2) an ejection phase velocity < or = 4 cm/s, usually with a gap between the ejection phase and aortic valve closure, or any shape of ejection but the typical single phase, and 3) an isovolumic relaxation phase velocity < 5 cm/s with an ejection phase velocity/isovolumic relaxation phase velocity ratio < 0.8. The accuracy for the identification of myocardial viability was: agreement 73%, kappa 0.44 for echocardiography, and agreement 75%, kappa 0.47 for PW-TDI.

CONCLUSIONS

PW-TDI nonviable patterns may be a helpful additional tool for the identification of patients without residual myocardial viability.