POLYMER MICROPARTICLES FOR RIGHT AND LEFT -HEART ECHOCARDIOGRAPHY ANDVISUALIZATION OF MYOCARDIAL PERFUSION AFTER PERIPHERAL VENOUS INJECTION

It is conceivable that a stable ultrasound contrast agent could be use d for reproducible right and left heart echocardiography and myocardia l visualization after intravenous injection. Microparticles from diffe rent polymers and preparation procedures were screened in six dogs lea ding to one superior agent with reproducible high quality echo contras t in doses of 1 mg/kg. This special agent is based on condensates of a spartic acid, ethanolamine and decanoic acid. Out of this material par ticles were formed with an average diameter of 2 micrometers. The easi ly suspendable particles were used for the following studies in a dose of 1 mg/kg intravenously in eight pigs. Maximal video intensity avera ged 116 +/- 42 relative intensity units (IU) in the right, 137 +/- 42 IU in the left ventricle, 42 +/- 7 in the normally perfused and 11 +/- 2 in the hypoperfused myocardium after circumflex ligature. The area under the intensity curve was 1942 +/- 100 IUxs in the right, 2452 +/- 1291 IUxs in the left ventricle, 518 +/- 124 in the normally perfused and 202 +/- 94 in the hypoperfused myocardium after circumflex ligatu re. There was no change of heart rate, central arterial or pulmonary a rtery pressure during and after the injections. There was also no loss of echo intensity during the passage of contrast material through the heart due to systolic pressure. The described agent can be used for t he opacification and ultrasonic visualization of the right and left he art as well as normally and hypoperfused myocardium without visible si de-effects in animal studies.