Relationship between Myocardial Performance Index and Severity of Coronary Artery Disease Assessed with SYNTAX Score in Stable Coronary Artery Disease

Background The aim of the study was to investigate the relationship between severity of coronary artery disease ( CAD ) assessed with SYNTAX score ( SS ) and myocardial performance index ( MPI ) in stable CAD . Methods The study participants consisted of 106 consecutive patients (mean age: 57.6 ± 9.5 years) with angiographically proven obstructive stable CAD and 30 patients with nonobstructive CAD (control group) (mean age: 58.0 ± 7.6 years). The MPI was calculated by using pulsed‐wave D oppler before coronary angiography. Coronary angiography was performed in all patients. The SS was prospectively calculated in 106 obstructive CAD patients. Patients were partitioned into 3 groups based on SS . Frequencies of risk factors, biochemical and hematological data were recorded in all patients. Results The SS tertiles were defined as SS low  ≤ 8 (n = 35), SS mid  ≤ 17 (n = 36), and SS high  > 17 (n = 35). The patients with SS high group (mean MPI ; 0,48 ± 0.06) based on SS had significantly higher MPI values compared with the SS mid (mean MPI ; 0,44 ± 0.05), SS low (mean MPI ; 0.43 ± 0.06), and control (mean MPI ; 0.41 ± 0.05) groups (P < 0.05 for all). The MPI levels of control group were also lower than compared with SS mid group (P = 0.006). The MPI value was significantly correlated with SS (r = 0.564, P < 0.001), diabetes (r = 0.355, P < 0.001), hypertension (r = 0.326, P < 0.001), and ejection fraction ( EF ) (r = −0.224, P = 0.018) in bivariate analysis. Multivariate regression analysis showed that MPI was independently associated with SS (β = 0.486, P < 0.001) and diabetes (β = 0.205, P = 0.028). Conclusion Although the normal EF , MPI value was impaired in proportion to the severity of  CAD in patients with stable CAD .