Can u have more than i bypass surgery?

Yes: Many people have had more than 1 bypass surgery. Fortunately, the surgery is very durable, and if there are problems years later, the treatment is often medication or stenting rather than re-do surgery.

Yes--may not need to: Coronary bypass is done these days using the mammary artery (from under the collarbone) to create a great size-matched bypass into the LAD (artery on the front of the heart). This almost always lasts a lifetime. Vein grafts may fail after 6 years ~ 50% of the time. It is often possible to treat these failures with stents of the original arteries (or the grafts) rather than doing another bypass.