Safety and efficacy of a new transpulmonary ultrasound contrast agent: Initial multicenter clinical results

Abstract

Myocardial contrast echocardiography has been found to be a safe and useful technique for evaluating relative changes in myocardial perfusion and delineating areas at risk. Although earlier contrast agents required direct delivery into the coronary arteries or aortic root, a new echocardiographic contrast agent, sonicated albumin microspheres (Albunex), has been found to cross the pulmonary circulation in experimental models. To determine the safety and preliminary efficacy of intravenous injections of Albunex in humans, 71 patients at three independent medical institutions underwent two-dimensional echocardiographic examination before, during and after the administration of three intravenous doses of Albunex, ranging from 0.01 to 0.12 ml/kg body weight. All patients provided a complete history and underwent physical and neurologic examination and laboratory and electrocardiographic evaluation before the injections; all evaluations (except for the history) were repeated at 2 h and 3 days after the injections of Albunex. The efficacy of the injections was qualitatively assessed by two independent blinded observers using a grading system of 0 to +3, with 0 indicating an absence of contrast effect and +3 indicating full opacification of the cavities examined. All injections were well tolerated and no serious side effects were noted in any of the patients. Irrespective of dose group, a cavity opacification greater than or equal to +2 was seen in the right ventricle in 212 (88%) of 240 injections and in the left ventricle in 151 (63%) of 240 injections as judged by the independent observers. The degree of ventricular cavity opacification appeared to be dose and concentration related.(ABSTRACT TRUNCATED AT 250 WORDS)

Quantification of transpulmonary echocontrast effects

“…For a detailed report on safety and efficacy of A1-bunex ® after intravenous injection, we refer to the recent study (Feinstein et al 1990) in which our center participated.…”

“…The protocol was approved by the Medical Ethics Committee of the hospital. The safety aspects have been reported recently (Feinstein et al 1990). …”

“…There were no laboratory, electrophysiologic, general physical or neurologic abnormalities detected either before, immediately after or three days after the study related to the injection of AIbunex ® or human serum albumin (Feinstein et al 1990). …”

“…The agent is safe and causes left heart opacification after intravenous injection (Feinstein et al 1990). We studied the in vitro behavior ofAlbunex ® in order to explain the observed contrast effects in the right and left ventricle after intravenous injection of increasing dosages of Albunex ® in humans.…”

Contrast echocardiography in Canada: Canadian Cardiovascular Society/Canadian Society of Echocardiography position paper

“…Substances with surfactant-like properties to reduce surface tension (14), as well as a protein shell to encapsulate the bubbles and limit outward gas diffusion, were included in some formulations (15). More recently, high-molecular-weight gases (mainly fluorocarbons) with low solubility in blood have been used to yield microbubbles with greater stability than the first generation, air-filled agents (16).…”