Medical device for flow augmentation in patients with occlusive cerebrovascular disease and methods of use

DETAILED DESCRIPTION The invention provides devices and methods for treatment of acute ischemic stroke and occlusive cerebrovascular disease by taking advantage of the collateral cerebral circulation.
Anastomoses between the cerebral arteries provide alternative pathways in which blood can reach a given region of the brain besides the predominant supplying artery.
At the base of the brain close to the sella turcica, circulus arteriosus cerebri, or Circle of Willis, connects the vertebral and internal carotid arteries to each other and to the vessels of the opposite side.
When occlusion of a blood vessel interrupting the flow of blood to a specific region of the brain occurs, survival of the brain tissue and therefore severity of a patient's neurological deficit depend on the number and size of its collateral arteries.
Effective stroke therapies therefore rely on the physicians' ability to respond to treatment quickly, since the longer the brain is deprived of blood flow, the greater the damage that occurs.
The devices and methods of the present invention are used to augment contralateral blood flow across the Circle of Willis to improve and maintain perfusion to an ischemic region distal to an occluded intra/extracranial cerebral artery, and thus can be utilized in stroke patients immediately after onset of symptoms to maintain viability of the cerebral tissue until the obstructing lesion is removed by an intervention or resolved with time (more than one half of the occluding thrombi usually lyse themselves in a few days).
One embodiment of the medical device comprises first and second elongate tubes.
Each tube has a manometer at a distal end and a lumen communicating with a port at the distal end.
An expandable occlusive member is optionally mounted on either or both tubular members proximal to the distal port and is adapted to expand to engage the lumen of an intracranial or extracranial artery.
A proximal end of each tubular member attaches to an oxygenator or a pump for aspirating blood through the first tube and perfusing the blood through the second tube