Updated

A summary of Vice President Dick Cheney's heart problems:

--1978: Cheney's first heart attack.

--1984: His second heart attack.

--1988: After suffering his third heart attack, Cheney had quadruple bypass surgery in August to clear clogged arteries.

--2000: Cheney suffered what doctors called a "very slight" heart attack, his fourth, and underwent an angioplasty to open a clogged artery.

--May 5, 2001: Just over 100 days later, Cheney felt chest pains and underwent another angioplasty to reopen the same artery.

--June 30, 2001: Cheney returned to the hospital and had a special pacemaker called an implantable cardioverter defibrillator, or ICD, inserted into his chest. During his 2004 annual checkup, doctors said the device had never automatically activated to regulate, which they said meant the heart was functioning normally.

--Nov. 13, 2004: Cheney entered the hospital after complaining of shortness of breath.

After the 2000 heart attack, Cheney quit smoking, began a daily 30-minute regimen on the treadmill and began eating healthier. He takes medication to lower his cholesterol.