Determination of the influence of risk factors for coronary artery disease on the effectiveness of cardiac surgery by the method of myocardial scintigraphy

Abstract

Background. Myocardial revascularization is a life-saving technology that not only increases life expectancy, reduces recurrences of myocardial infarction and repeated surgery, but also improves its quality in patients with coronary artery disease. Risk assessment, the complexity of coronary artery disease, the presence of comorbidities, the area of hibernating myocardium, the patient’s consent are the basis for choosing a method of treatment. Positive structural and functional changes of the myocardium (increase in the area of viable myocardium), restoration or improvement of left ventricular systolic function (increase in ejection fraction and decrease in end-diastolic volume), reduction of angina are the expected result of the surgical treatment. Purpose – determining the influence of risk factors for coronary heart disease on the outcome of surgical treatment by aorto-coronary artery bypass grafting with the help of diagnostic evaluation of myocardial scintigraphy. Materials and Methods. To achieve the clinical tasks, 62 patients with coronary artery disease were examined. The mean age of the subjects was (59.6 ± 8.2) years. Myocardial scintigraphy was performed in SPECT with ECG synchronization (Gated SPECT). 99mTc-MIBI with an activity of 555–740 MBq was used. Myocardial scintigraphy was performed over time of treatment (before and after coronary artery bypass grafting) according to the protocol – One Day Rest. Results. The influence of risk factors was assessed using dynamic and static integrated indicators. The dynamic integral indicator did not show statistically significant risk factors: smoking (p = 0.54), left ventricular contractility (p = 0.43), the presence of myocardial infarction in past (p = 0.4), heart failure stage (p = 0.53) and functional class of angina (p = 0.08). The static integrated indicator also did not show statistically significant effects from smoking (p = 0.13), left ventricular contractility (p = 0.58), the presence of myocardial infarction in past (p = 0.1), heart failure stage (p = 0.11) and functional class of angina (p = 0.6). Conclusions. The risk factors for coronary artery disease, such as: myocardial infarction in past, left ventricular contractility, heart failure stage, functional class of angina and smoking, in the study group of patients, had no reported effect on revascularization by the method of aorto-coronary artery bypass grafting (static and dynamic integrated indicators p > 0.05).