At West Point, Dwight Eisenhower began chain smoking three or four packs of cigarettes a day. 

In September 1955 he suffered a massive heart attack after golfing in Denver, Colorado.

Seven weeks later he left the hospital, and in February 1956 doctors reported his full recovery.

Eisenhower was the first president to release information about his health and medical records while in office, but it seems that people around him deliberately misled the public about his health to suggest he was healthy enough to do his job.

His cardiologist Dr. Paul Dudley White regularly informed the press of the President’s progress. Instead of eliminating him as a candidate for a second term as president, Dr. White recommended a second term as essential to his recovery.

In November 1956 President Dwight Eisenhower was elected for his second term.

As a consequence of his heart attack, Eisenhower developed a left ventricular aneurysm, which was in turn the cause of a mild stroke in November 1957. 

Main Source: Wikipedia