The present invention relates to methods of dilating coronary arteries, and more particularly to methods utilizing balloon-type catheters to dilate arteries in the area of obstructions therein.
It has long been desired to increase the blood supply to the heart through the coronary arteries when those arteries have become clogged through the build-up of cholesterol plaque and/or other substances. Coronary bypass operations have for many years been utilized for this purpose, which operations normally include sewing segments of leg vein onto such arteries to shunt blood around blocked areas. Such coronary bypass operations have achieved considerable success in relieving symptoms associated with this condition.
More recently, a technique introduced in Switzerland by Dr. Andreas Gruntzig relies upon a balloon-type catheter which is inserted through a guide catheter to a point where the balloon portion of the catheter is disposed within a cholesterol plaque blockage. The balloon is then inflated compressing the plaque and clearing the passage. While this technique shows considerable promise, difficulties have been encountered in working the catheters through the arteries to the point of blockage. This and other complications are also likely to result as a result of the complete heparinization of the patient during the performance of the Gruntzig technique of coronary dilation. It would, of course, be desirable to improve the reliability of this technique, while at the same time decreasing risk which is attendant thereto.