Purpose. To develop and clinically approve method for correction of blurring artefacts of the left ventricle to improve single photon emission computed tomography of myocardial perfusion imaging. Materials and methods. A total of 42 patients (39 of patients were males and 3 of patients were females) who had cardiac ischemia were examined by this method. Invasive (n=30) and MSCT (n=30) coronary angiography were performed in patients according to indications. Patients with coronary artery stenosis were conducted in ECG-gated myocardial perfusion scintigraphy with pharmacological stress test and a functional rest study. Computer processing of native images was carried out using special software which allowed for the reconstruction of static tomographic images without ECG-synchronization and 16 series of the tomographic images characterizing the myocardial perfusion at different phases of the cardiac cycle. Diastolic phase of cardiac circle was used for further analysis of myocardial perfusion. According to the results of invasive coronary angiography (n = 30) and MSCT (n = 12) patients were divided into two groups: group 1 included patients with CAD and the presence of coronary artery stenosis ≥ 70% (n = 18); group 2 comprised patients with coronary artery stenosis < 70% (n = 24). The sum of the stress scores of all segments (SSS) and extent of perfusion defects during stress test (Stress Extent) were determined from these values. Results. The average myocardial perfusion values in patients with coronary artery stenosis less than 70% during the diastolic phase images were significantly lower than the corresponding values obtained without cardiac motion correction: SSS 5(3-7) and 6, 5(5-9), (p<0, 01); Stress Extent 9, 5% (5, 5-17, 5%) and 12% (9-21, 5%), (p<0, 01), respectively. The average myocardial perfusion values in patients with coronary artery stenosis more than 70% in the diastole phase images were significantly higher than the corresponding values obtained without cardiac motion correction: SSS 23(19-31) and 21 (8-22), (p<0, 01); Stress Extent 44, 5(35-63) and 39% (18-50%), (p=0, 01), respectively. ROC analysis showed that the sensitivity and the specificity rates of MPS performed with cardiac motion correction were significantly (p < 0.05) higher compared with those obtained based on the assessment of summation images. Conclusion. The myocardial perfusion values obtained based on the analysis of enddiastolic series were significantly more informative then those obtained by the classical method in the diagnosis of angiographically significant (luminal narrowing ≥ 70%) coronary artery stenosis. This method allows to reduce the rates of false positive and false negative MPS results and to provide more accurate diagnosis of hemodynamically significant stenosis of the coronary arteries.
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging