Prognostic value of echocardiographic-derived calcium index in coronary artery disease diagnosed by 64-multidetector computed tomography.

PURPOSE: To determine whether echocardiographic calcium index (ECI) calculated using transthoracic echocardiography (TTE) predicts coronary ischemic events. We also wished to determine coronary artery calcium score (CACS), the presence of obstructive coronary artery disease (CAD) and plaque composition, all of which were assessed by multidetector computed tomography (MDCT). METHODS: We carried out a prospective cohort study of 82 consecutive outpatients with chest pain and low-moderate risk of CAD, referred for noninvasive coronariography by MDCT. ECI was blindly assessed by TTE and correlated with subsequent cardiovascular events during a follow up period of 36 months. RESULTS: ECI values of ≥7 had a sensitivity of 77.3%, a specificity of 90%, positive predictive value of 73.9%, and negative predictive value of 91.5% with respect to future coronary ischemic events. In addition, patients with ECI ≥ 7 showed a greater presence of severe calcified and obstructive CAD and a linear increase of obstructed vessels and mixed and calcified plaques, with a linear trend according to ECI values. CONCLUSION: ECI values of ≥7 determine poor CAD prognosis in relation to ischemic events. Furthermore, ECI ≥ 7 may serve as a marker of content of coronary artery calcium, intraluminal obstruction, and plaque composition. Therefore, ECI seems to provide prognostic information as well as information about the characteristics of the plaque of atheroma.