Method and Apparatus for Mitigating Acute Reoxygenation Injury During Percutaneious Coronary Intervention

Abstract

A system and methods are described for improving the management of ischemic cardiac tissue during acute coronary syndromes. The system combines a catheter-based sub-system which allows for simultaneous balloon dilation of a coronary artery and infusion of a carefully controlled perfusate during percutaneous coronary intervention. The system allows for modulation of levels of oxygen at the time of percutaneous intervention. In addition, catheters and systems are provided for administration of fluids with modified oxygen content during an intervention that incorporate upstream flow control members to compartmentalize the perfusion of the target coronary artery and the remainder of the heart.

We claim: 
     
         1 . A method of treating a patient undergoing an interventional procedure in which blood flow to a tissue has been reduced comprising:
 a. Having a tissue in an ischemic state relative to its normal state;   b. Having an occlusion upstream of the tissue causing the ischemic state;   c. Providing a catheter comprising an infusion lumen wherein the infusion lumen is designed to provide infusion of a fluid to the tissue which tissue is distal to the occlusion;   d. Inserting the catheter in the blood vessel; and   e. Infusing a modulated oxygen content fluid through the infusion lumen wherein the fluid has a change in oxygen concentration, the oxygen concentration being controlled by an oxygenation controller.   
     
     
         2 . The method of  claim 1  further including the step of determining an oxygen content of the blood flow downstream of the occlusion prior to the step of infusing a modulated oxygen content fluid. 
     
     
         3 . The method of  claim 1 , wherein a normal blood flow is not reestablished to the tissue before the infusion. 
     
     
         4 . The method of  claim 1  further including the steps of placing an angioplasty balloon within the occlusion, and inflating the angioplasty balloon before the step of infusing a modulated oxygen content fluid. 
     
     
         5 . The method of  claim 1 , wherein the step of infusing a modulated oxygen content fluid, the oxygen content in the fluid is increased over time. 
     
     
         6 . The method of  claim 1 , wherein the fluid comprises the patient's blood. 
     
     
         7 . The method of  claim 1 , wherein partial pressure of oxygen in the fluid is increased from about 20 mmHg to about 110 mmHg. 
     
     
         8 . The method of  claim 1  further including the steps of determining an oxygen content in blood flow downstream of the occlusion during the step of infusing a modulated oxygen content fluid and adjusting the oxygen content in the fluid being infused based on determined oxygen content. 
     
     
         9 . The method of  claim 1 , wherein the step of infusing a modulated oxygen content fluid, the oxygen content of the fluid is changed at constant fluid pressure. 
     
     
         10 . The method of  claim 1  further including the step of blocking the blood vessel proximal to the occlusion prior to the step of infusing modulated oxygen content fluid. 
     
     
         11 . The method of  claim 1 , wherein a proximal occluding member provides control of perfusion of unmodified blood. 
     
     
         12 . The method of  claim 1 , wherein the oxygen content is increased over time. 
     
     
         13 . The method of  claim 1  wherein the oxygen concentration is intentionally hypoxic for the tissue in the tissue's normal state for at least some period of time.