Opacification and border delineation improvement in patients with suboptimal endocardial border definition in routine echocardiography: Results of the phase III albunex multicenter trial

Objectives. This study was designed to assess the safety and efficacy of intravenously administered sonicated human serum albumin for enhancing echocardiographic delineation of the left ventricular endocardium and improving assessment of wall motion in patients with incomplete depiction of noncontrast echocardiography. Background. Echocardiographic regional wall motion analysis is impaired by incomplete endocardial definition in as many as 10% of patients. Sonicated human serum albumin is a stable contrast material that, unlike other agents, opacifies the left ventricle when administered intravenously. Methods. One hundred seventy-five patients were enrolled at eight centers on the basis of incomplete echocardiographic endocardial depiction. Sonicated 5% human serum albumin, a stable preparation of air-filled microspheres (size range 1 to 10 μm), was administered intravenously in divided doses: 0.08 ml/kg body weight in all patients, followed by 0.14 and 0.08 ml/kg or a single dose of 0.22 ml/kg, depending on the result of the initial dose. Investigators and independent reviewers blinded to the protocol scored the echocardiograms for degree of left ventricular opacification and improvement of endocardial border depiction. Results. Overall, 81% of patients had at least moderate left ventricular chamber opacification with at least one contrast dose, and endocardial definition was improved in 83%. In the subgroup with inadequate left ventricular opacification from the initial dose, a second, larger dose (0.22 ml/kg) improved endocardial depiction in 64%. No significant side effects occurred. Conclusions. In patients with incomplete echocardiographic endocardial definition, sonicated human serum albumin is a safe, effective contrast agent that, when administered intravenously, produces left ventricular chamber opacification, improves endocardial depiction and enhances regional wall motion analysis.