Geesh the man has had a few heartattacks. Heartattacks are a common ailment for many Americans. Must we make Cheneys life miserable on every issue? We have had quite a few presidents who were ill during their terms. This in no way makes them unfit. I forgot the president but he had cancer and had a special surgery in secret for it. Reagan had various illnesses. If a person is sickly it does not mean they can't preform their job.
Three Notable Presidents who had rather severe illnesses of the last century: Franklin Delano Roosevelt, John Fitzgerald Kennedy and Ronald Reagan.
The three of them arguably some of the best Presidents of the last century despite their illnesses.
You could add Eisenhower to that list.