An automated coronary artery occlusion device for stimulating collateral development in vivo.
BACKGROUND
Repetitive, brief coronary artery occlusions produce collateral development in experimental animals. This model causes coronary collateralization in a highly reproducible fashion, but the process is very labor intensive. We report the design and use of a fully automated hydraulic coronary occlusion device capable of producing repetitive coronary occlusions and enhancement of coronary collateral development in dogs.


METHODS
The device consists of analog electronics that allow adjustment of occlusion number, frequency, pressure and duration, and mechanical components responsible for the coronary occlusion. The motor and piston of the device are coupled to a chronically implanted hydraulic vascular occluder placed around the left anterior descending coronary artery (LAD) of dogs instrumented for measurement of systemic and coronary hemodynamics. One group of dogs (n = 6) underwent brief (2 min) LAD occlusions once per hour, eight times per day, 5 days/week for 3 weeks to stimulate collateral development (measured using radioactive microspheres). Another group of dogs (n = 6) that did not receive repetitive occlusions served as controls.


RESULTS
The device reproducibly produced repetitive LAD occlusions for the duration, frequency, and time interval initially programmed. A time-dependent increase in transmural collateral blood flow was observed in dogs undergoing repetitive occlusions using the device. Collateral blood flow was unchanged in dogs that did not undergo occlusions.


CONCLUSIONS
The automated occluder device reliably produces repetitive coronary occlusions and may facilitate further study of coronary collateral development in response to chronic myocardial ischemia.
Rys
Richard
R
Department of Anesthesiology, Medical College of Wisconsin, MEB-M4280, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA.
LaDisa
John F
JF
Tessmer
John P
JP
Gu
Weidong
W
Kersten
Judy R
JR
Warltier
David C
DC
Pagel
Paul S
PS
D000818:Animals; D003097:Collateral Circulation; D003250:Constriction; D003326:Coronary Circulation / Q000502:physiology*; D003327:Coronary Disease / Q000503:physiopathology*; D003331:Coronary Vessels / Q000502:physiology; D004195:Disease Models, Animal; D004285:Dogs; D004867:Equipment Design; D008955:Models, Cardiovascular