Clinton's surgery nothing new, yet unique

With heart disease by far the No. 1 cause of death in the United States, former President Bill Clinton was hardly alone in his need for bypass surgery.

More than 500,000 of the operations were performed in the United States in 2001, according to the Centers for Disease Control and Prevention.

Mr Clinton's office said the 58-year-old was resting comfortably after a five-hour heart bypass operation at a New York hospital on Monday. He was admitted to New York-Presbyterian Hospital on Friday after complaining of chest pains and shortness of breath.

Heart bypass operations may be common, but surgeons still face many uncertainties when they crack open patients' chests. Imaging techniques can only show doctors so much beforehand, and each patient is unique.

Mr Clinton's doctors described the quadruple bypass operation as "relatively routine" and that it probably prevented Mr Clinton from having "a substantial heart attack" in the near future.

Coronary artery bypass grafts, CABG or "cabbage" for short, create a detour around a badly blocked artery or arteries so that the heart can pump blood properly. Most critical are the three major coronary arteries, which supply the heart with oxygen and nutrients. But other blocked arteries may also be bypassed.

The surgeon must look at the blocked arteries before deciding whether to take a vein from the leg and use it to make a new graft, or whether to re-route an artery from the chest wall. Often, a combination of both methods is used, according to the Society of Thoracic Surgeons.

During a typical open heart operation, the surgical team opens the patient's chest by sawing through the sternum, or breastbone, the flat area of bone in the middle of the chest.

After assessing the condition of the heart and arteries, the surgical team puts the patient onto a heart-lung machine. Then the heart is stopped and the surgery begins.

Tiny stitches attach the new arteries to the heart. This can take hours, especially if several bypasses are needed.

Pacing wires are put onto the heart's surface to help restart the heart or control its rate if needed. Poked through the skin and attached to a pacing machine, they can be pulled out a few days after surgery.

The risks of bypass surgery are fairly low and most relate to the use of general anesthesia, or the heart-lung machine that keeps blood flowing and oxygenated while the heart is stopped.

These risks include pneumonia, improper heart rhythm or arrhythmia, kidney failure and blood clots.

Doctors said the typical hospital stay after a bypass is four to six days.

Then Mr Clinton would typically be put on a cocktail of heart drugs to prevent new blockages - aspirin and perhaps another drug to thin the blood, a beta blocker and probably an ACE inhibitor to control blood pressure and a statin drug to control cholesterol.