Myocardial ischemia assessed by Tc99m MIBI SPECT and left ventricle regional systolic and diastolic function evaluated by tissue Doppler echocardiography

Background: Tc99m MIBI single-photon emission computed tomography (SPECT) study facilitates the evaluation of the regional myocardial perfusion and tissue Doppler echocardiography imaging facilitates the quantitative assessment of the regional systolic and diastolic function of the myocardium. The aim of the study was an assessment of the correlation between regional rest myocardial perfusion defects and regional rest systolic and diastolic myocardial velocities in patients with ischemic heart disease (IHD). Material and methods: In 40 IHD patients (33 men, 7 women) aged 43–74 years (mean 56 years) rest SPECT imaging with Tc99m MIBI and rest tissue Doppler examinations were performed. The control group consisted of 35 healthy sex and age matched pesons. The left ventricle was divided into 13 segments. The number of non-perfused segments in three myocardial perfusion regions (left anterior descending artery, circumflex artery, right coronary artery) was assessed in IHD patients. During tissue Doppler examination the maximal systolic and maximal early diastolic velocity of the myocardium in each segment were established in both examined groups. Results: The systolic and diastolic myocardial velocities were significantly lower in IHD group as compared to control group. In the IHD group statistically significant decrease of systolic and diastolic velocities in relation to the number of non-perfused segments was found. In comparing the linear regression slopes for systolic and for diastolic myocardial velocities in terms of intensification of perfusion defects, a more pronounced decrease in diastolic velocity was encountered. Conclusions: Both systolic and diastolic myocardial velocities are decreased in the myocardial regions with perfusion defects, but the reduction of the diastolic velocity is higher than the reduction of the systolic velocities. Thus our results indicate a good correlation between the intensity of perfusion abnormalities and myocardial velocities. The levels of diastolic dysfunction is more pronounced than the level of systolic dysfunction in the ischemic myocardium.