|Budget Amount *help
¥3,000,000 (Direct Cost : ¥3,000,000)
Fiscal Year 1998 : ¥1,300,000 (Direct Cost : ¥1,300,000)
Fiscal Year 1997 : ¥1,700,000 (Direct Cost : ¥1,700,000)
Development of intra-aortic stent for acute dissection in the descending aorta, which is designed to be percutaneously inserted and to promote the thrombus formation in the pseudolumen, is the goal of this project.
At the start, we tried to make novel animal model of aortic dissection at the descending aorta. In conventional animal models, aortic dissection has a tendency of high spontaneous recovery due to its embolic obstruction, because it has only an entry of the dissection. Then, in the present experiment, we made both entry and re-entry on the aortic dissection and observed the long term course of this model more than 2 years. The result was remarkable : the patency of the pseudo-lumen on new method was 100% in the aorta.
On this animal model, we implanted an intravascular stent percutaneously. In order to prevent graft migration, however, a stent must be press the aortic wall strongly. With such strong pressure, the weak aortic is easy to rupture. .This is a contradicing dilemma.
In order to solve this dilemma, we develop an new cylindrical balloon to obstruct temporally the pseudo lumen. We applied new cylindrical balloon in the aortic dissection model of the descending aorta. When we inflate the balloon, the entry of the pseudo-lumen close. The evaluation of the blood flow of the true lumen and the false-lumen was carried out with a ultrasonic echograph. The present result indicated that when we obstruct the entry with our new balloon at least 6 hours, the false lumen collapse completely with the thrombus. Thus this method is promising for the treatment of the acute dissection of descending aorta, as a epoch-making clinical treatment method. Accordingly we continue to study in an attempt to clinical application.