NONINVASIVE ASSESSMENT OF CORONARY BLOOD FLOW DURING ECHOCARDIOGRAPHY FOR RISK STRATIFICATION OF PATIENTS WITH NEGATIVE TEST RESULTS UPON FAILURE TO ACHIEVE SUBMAXIMUM HEARTBEAT RATE

Negative stress echocardiography (SE) results suggest a favorable prognosis. However, this is true only if a submaximum heartbeat rate (HBR) is achieved in a patient. The objective of the present study was to assess the prognostic significance of coronary blood flow parameters of the anterior interventricular artery (AIVA) upon SE under physical load stress in patients who did not achieve a submaximum HBR. Materials and methods: Physical load SE data obtained for 268 patients aged 54±10 years, among whom 156 were men, were analyzed. SE data were supplemented with the results of measuring AIVA blood flow parameters using Doppler sonography. The coronary reserve value of AIVA (CRAIVA) was calculated. The patients were divided into the following groups: 1) 35 patients who did not achieve a submaximum HBR and whose CRAIVA was 2; and 3) 179 patients who achieved a submaximum HBR. Adverse events were analyzed three years thereafter. Results: In 8 patients, adverse events included 2 nonfatal myocardial infarctions and 6 revascularization events. No differences in adverse event rates between Groups 3 and 2 were found (1,75% vs. 3,7%, p=0,37). A significant increase in adverse event rate was found in Group 1 compared with Group 3 (8,6% vs. 1,75%, p<0,03), including the most severe outcomes, i. e., MI/coronary artery bypass (5,7% vs. 0%, p<0,002). Conclusion: ES upon physical load should be supplemented with coronary blood flow determination in AIVA.