Prognostic Value of Circumflex Artery Motion as a Measurement of Left Ventricular Long-Axis Systolic Function in Patients Treated With Percutaneous Coronary Intervention

Abstract

Background: Accurate assessment of LV systolic function during primary PCI can help to optimize reperfusion strategies and has many prognostic implications. Circumflex artery motion (CAM) can be measured during primary PCI to reflect LV long-axis function which is an accurate indicator of LV systolic function. Aim of the work: to test the validity of CAM as a measurement of LV long-axis systolic function in anterior STEMI patients treated with primary PCI and to determine its prognostic value. Patients and Methods: CAM was measured using coronary angiography during primary PCI in 50 STEMI patients. Echocardioghraphic (M-mode, tissue Doppler and speckle-tracking) assessment of LV long-axis systolic function was performed within 24 hours after primary PCI. Follow-up echocardiography was scheduled after 6 months. Reverse remodeling was defined as a reduction >10% in LV end-systolic volume by the end of follow-up period. Results: Strong correlation was found between CAM and echocardiographic parameters of LV long-axis systolic function (p for each < 0.001) as well as LVEF (r= 0.845, p< 0.001) 24 hours after successful primary PCI. Patients were dichotomized according to the median value of CAM (median CAM: 13.9 mm). Supra-median CAM was associated with higher LVEF (56.0±7.4 vs. 42.6±3.6, p<0.001), lower peak troponin (6.43±2.6 vs. 11.13±2.78 ug/L, p<0.001) and lower incidence of composite major adverse cardiac events (3.8% vs. 45.8%, p=0.001). A CAM cutoff value of 10.8 mm (sensitivity 96% and specificity 100%) accurately predicted reverse remodeling at 6 months. Conclusion: CAM measured at the time of primary PCI can predict LV systolic function loss, adverse clinical outcome and reverse remodeling in STEMI patients. Thus it can gauge the choice of reperfusion strategy and adjunctive therapy.