Generally, if the blockages are located in the initial or the proximal portion of the coronary artery, and if that artery is subtending a large area of the muscle of the heart, then it should be opened with bypass surgery rather than angioplasty. This is more so true when the blockages are heavily calcified or have a heavy thrombus or cholesterol burden or if the arteries are tortuous and such other technical reasons which make the result of angioplasty sub-optimum. In such vessels, bypass surgery is a better choice.