Author + information
- Received April 22, 1983
- Revision received August 16, 1983
- Accepted August 16, 1983
- Published online January 1, 1984.
- Steven B. Feinstein, MD*,
- Folkert J. Ten Cate, MD,
- Werner Zwehl, MD,
- Kenneth Ong, PhD,
- Gerald Maurer, MD,
- Chuwa Tei, MD, FACC,
- Pravin M. Shah, MD, FACC,
- Samuel Meerbaum, PhD, FACC and
- Eliot Corday, MD, FACC
- ↵*Address for reprints: Steven B. Feinstein, MD, Department of Cardiology, 691/IIIE, Wadsworth Veterans Administration Hospital, Sawtelle and Wilshire Boulevard, Los Angeles, California 90073.
To facilitate the passage of echo contrast agents through the microcirculation and the echocardiographic study of myocardial perfusion, ultrasonic energy (sonication) was employed to produce contrast agents consisting of relatively uniform, stable and small (< 10 μ diameter) gaseous microbubbles suspended in liquid solutions. The size and persistence of the microbubbles was verified by light microscopy and an in vitro system were employed for comparative assessment of peak echo amplitude and echo persistence characteristics of various contrast agents. The study indicated that although a variety of hand-agitated and sonicated contrast agents provided satisfactory echo intensities, sonication was clearly superior to the hand-agitation method, because sonication produced smaller, more uniform and more stable microbubbles that may be suitable for myocardial contrast echocardiography.
It is concluded that of the contrast agents examined, sonicated solutions of sorbitol (70%) and dextrose (70%) appeared to have particular potential because of the small sizes of the microbubbles (6 ± 2 and 8 ± 3 μ, respectively) and their prolonged in vitro persistence. The use of sonication to produce standardized, small and stable microbubbles should facilitate physiologic passage of the contrast agent through the capillary beds and allow two-dimensional imaging of the left heart myocardium during right-sided, aortic root, coronary sinus or intraco-ronary contrast injections.
This study was supported in part by Grants HL 17651-08 and HL 14644-09 from the National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland, the Ahmanson Foundation, Mr. and Mrs. E. E. Fogelson, Mr. and Mrs. Randolph Scott, Ms. Joan and Mrs. Pearl Borinstein, Mrs. Rita Schreiber, the Mitchell Family Foundation, the Jules Stein Foundation, and Mr. and Mrs. Harry Roman and Mrs. Dorothy Forman, Los Angeles, California.
- Received April 22, 1983.
- Revision received August 16, 1983.
- Accepted August 16, 1983.
- American College of Cardiology Foundation