Albunex: A Safe and Effective Commercially Produced Agent for Myocardial Contrast Echocardiography

Microbubble solutions of sonicated human serum albumin have been shown to be effective echocardiographic contrast agents free from adverse effects on coronary blood flow, left ventricular function, and systemic hemodynamics. Albunex is a commercially prepared solution of air-filled albumin microspheres prepared from sonicated 5% human serum albumin. The effects of Albunex on coronary blood flow, left ventricular function, and systemic hemodynamics, as well as contrast enhancement were evaluated in 10 open chest, anesthetized dogs. After an intracoronary injection, Albunex did not alter left atrial, left ventricular systolic or end-diastolic, or mean aortic pressures. It did not cause a coronary hyperemic response, alter left ventricular systolic thickening, or lower the peak positive left ventricular dp/dt. It did not alter these measurements even in the presence of a critical coronary stenosis. The contrast opacification produced by Albunex microbubbles was dose dependent (optimal dose range of 0.033 to 0.5 ml/kg), with attenuation occurring at higher doses. In conclusion, although Albunex provides adequate contrast enhancement, intracoronary injection of Albunex does not significantly alter coronary blood flow, left ventricular function, or systemic hemodynamics. Because of the standardized size and concentration of the microspheres, Albunex may be an ideal agent for myocardial contrast echocardiography.