Cheney's history of heart problems
(CNN) -- Vice President Dick Cheney's history of heart problems started in 1978, when he suffered his first of four heart attacks at the age of 37.
Attention turned to Cheney's health after he was taken to George Washington University Hospital for tests on Saturday after an episode of shortness of breath.
The following is a summary of Cheney's heart problems:
1978: Dick Cheney suffers his first heart attack. The incident does not sideline Cheney, as the former White House chief of staff wins the first of five terms to Congress that same year.
1984: Cheney has another heart attack while serving as Wyoming's lone U.S. representative. Doctors consider the heart attack minor, like the 1978 incident, and Cheney soon heads back to work, eventually representing the Republicans as minority whip in the House.
1988: An attack in August -- Cheney's third before his 48th birthday -- leads to quadruple bypass surgery. But the congressman's condition stabilizes throughout the 1990s, with no official reports of health problems. He has his last comprehensive heart checkup in 1996, without having another for four years.
November 22, 2000: With the presidential election hanging on a few hundred votes in Florida, Cheney checks into George Washington University Hospital with chest pains. Doctors insert a coronary stent to prop open a narrowed artery after what Cheney calls "a very slight heart attack." Doctors say Cheney should be able to resume all his normal activities.
March 5, 2001: Cheney checks himself into George Washington University Hospital with chest pain and discomfort. The vice president undergoes an urgent procedure to re-open the blocked heart artery treated in November, returning home after an overnight stay. With advisers saying his heart has not been damaged, Cheney soon resumes his busy schedule.
June 29, 2001: Cheney says he will undergo tests to determine whether he needs a "pacemaker plus," a device to normalize an irregular heartbeat. Cheney calls the procedure "an insurance policy" given his history of heart problems.
June 30, 2001: Doctors say Cheney's prognosis is "terrific" after he has surgery to implant a device to monitor his heart rhythm and slow it down if necessary. Cheney leaves the hospital that afternoon.
February 8, 2002: Cheney completes a "routine" physical to allow doctors to check the status of his heart pacemaker device. No complications were reported.
May 11, 2004: Doctors give Cheney a clean bill of health after his annual heart checkup. They find that his pacemaker had detected no irregular heartbeat, a spokesman said. During the visit, the vice president underwent an EKG, and echocardiogram, a stress test, a regular physical and a check of his pacemaker.