Evaluation of the effectiveness of revascularization in coronary artery disease according to dynamic PET/CT of the myocardium with 13N-ammonium

Aim. To evaluate the impact of percutaneous coronary intervention (PCI) on global and regional myocardial blood flow (MBF) parameters obtained by positron emission tomography (PET) in patients with stable coronary artery disease (CAD). Materials and methods. Fifty-seven patients with stable form of CAD were enrolled in this study: among them 32 had obstructive CAD (70% stenotic lesion in one or more coronary artery) and were underwent PCI; 25 patients were treated conservatively. All patients underwent serial dynamic PET scan: before and after PCI as well as in follow up after medical treatment only. Rest and stress emission data were obtained; semiquantitative analysis (SSS, SDS) was performed as well as absolute MBF assessment per patient and per vessel basis and included MBF at rest and stress and myocardial flow reserve (MFR). Results. There was an overall significant reduction in ischemia after PCI: SSS 15.0 (8.8; 20.3) before and 7.0 (3.8; 12.3) after the procedure, SDS 10.0 (7.8; 15.0) before and 4.5 (1.8; 7.0) in follow up (p0.001) and significant improvement in global stress MBF (р0.001) and MFR (р=0.002) values. In vascular territories after PCI regional values of stress MBF and MFR significantly increased (р0.001 and р=0.002 respectively), while in remote areas significant increase observed only for stress MBF (р=0.004) without change for MFR (р=0.063). Change in absolute terms for stress MBF was more apparent in PCI-regional than in remote areas – 0.37 (0.05; 0.67) ml/g/min vs 0.15 (-0.14; 0.52) ml/g/min; р=0.019. Conclusion. After PCI apparent improvement of global perfusion in terms of semiquantitative and quantitative metrics was obtained, while no significant changes were observed in the medical treatment group. Positive changes of stress MBF values were in coronary PCI-territories as well as in remote areas. Increase of MFR observed in coronary PCI-territories only.