Redistribution of Perfusion and Myocardial Function in Patients With Multivessel Disease and Myocardial Infarction With ST Segment Elevation After Recanalization of an Infarct-Associated Artery According to the Results of Single Photon Emission Computed Tomography, Synchronized With Electrocardiography

Abstract

BACKGROUND Numerous studies have shown that coronary reperfusion with primary percutaneous coronary intervention (PCI) improves outcomes in patients with ST-segment elevated myocardial infarction (STEMI). However, the question of the effect on the myocardium as a whole of an isolated intervention on an infarct-related artery in multivessel coronary disease remains incompletely studied.AIM OF STUDY To study the features of perfusion redistribution and myocardial function using perfusion single photon emission computed tomography (SPECT) in patients with STEMI and multivessel coronary disease after isolated PCI on an infarct-related artery.MATERIAL AND METHODS SPECT-ECG (electrocardiography) was performed in 32 patients (27 men and 5 women) with STEMI. According to the ECG results, the location of focal myocardial changes was regarded as “lower” MI in 19 (59%) patients, “anterior” in 13 patients (41%). Coronary angiography revealed a multivessel lesion of the coronary vessels in all of them. The patients were divided into groups according to the location of the infarction and the area of the lesion: group 1 — lower MI (stenting of the right coronary artery (RCA) and its branches) — 19 patients (mean age — 57.7±2.5; median — 55 [51.5; 63.5]), of which 8 with small-focal (1a) and 11 with large-focal infarction (1b); group 2 — anterior MI (stenting of the left coronary artery (LCA) and its branches) — 13 patients (mean age — 55.4±3.5; median — 54 [48.5; 62.5]), of which 5 with small-focal (2a) and 8 with large-focal infarction (2b). SPECT-ECG was performed 3 times: 1st — on days 2–3 after PCI of the infarct-related artery, 2nd — 6 days after PCI, and 3rd — 6 months after PCI.RESULTS After RCA stenting in patients with lower MI and multivessel coronary disease, SPECT-ECG revealed a statistically significant decrease in local contractility of individual segments of the anterior septal and lateral walls (with sufficient revascularization of the RCA system) and worsening of perfusion and right ventricular (RV) volumes. After stenting of the LCA branches in patients with anterior MI and multivessel coronary disease, a statistically significant decrease in local contractility in the basal segment of the diaphragmatic wall was observed, as well as impaired perfusion and an increase in the volume of the RV (with successful revascularization of the anterior interventricular branch). All these findings could be the result of partial steal of the blood supply to neighboring areas and myocardial remodeling after PCI in patients with multivessel coronary artery disease.CONCLUSION 1. According to the data of single-photon emulsion computed tomography synchronized with electrocardiography in the early and late period of myocardial infarction after percutaneous coronary intervention in patients with multivessel coronary disease, there is a significant improvement in perfusion and function of the infarct-associated artery system. 1. Recanalization of only the left coronary artery with remaining stenoses in the right coronary artery in the long-term period can lead to an increase in the size of the cavity of the right ventricle of the heart and uneven distribution of perfusion in its The revealed statistically significant disturbances in perfusion and local contractility of neighboring areas after percutaneous coronary intervention of an infarct-related artery may be the result of steal of the blood supply and early myocardial remodeling in multivessel disease. 3. Disturbances in perfusion and local contractility in neighboring myocardial blood supply pools after percutaneous coronary intervention of an infarct-related artery dictates the need to repeated single-photon emulsion computed tomography synchronized with electrocardiography as early as possible in patients with multivessel coronary disease in order to assess the redistribution of perfusion and myocardial remodeling for timely complete revascularization, preventing recurrent coronary

Keywords

• myocardial infarction
• multivessel coronary disease
• perfusion and myocardial function
• right ventricular dilatation
• spect-ecg