"My health is very much improved. It has been a long time since I have felt this good," Walesa said in a statement. "I have received medical care all over the world, and I never felt quite so good as I do today. This is a very good outcome and I am overjoyed that I do not need a heart transplant at this time."
Walesa, whose doctors have put him on an exercise program, planned to travel to Mexico to participate in a youth conference.
"I hope to work harder than ever to help people around the world," he said. "Dictators and oppressors should continue to fear me because I will be here for a long time."
Walesa came to Houston for tests last week and had a stent implanted into a clogged coronary artery. Among his symptoms were chest pain, fatigue and shortness of breath. He previously had a heart attack and suffers from sleep apnea and diabetes.
The device implanted Feb. 29 is a biventricular pacemaker-defibrillator. The pacemaker synchronizes the contractions of his heart, while the defibrillator will be on standby to shock the heart if needed.
Walesa's doctors hope the pacemaker, along with a stent and the treatment Walesa received for his sleep apnea and diabetes, will prevent the need for a heart transplant, said Dr. Guillermo Torre, his cardiologist.
Doctors should have a better idea in the next three months whether a heart transplant will be needed.
Walesa, a former Gdansk shipyard electrician, led a workers' strike in 1980 that grew into the nationwide Solidarity freedom movement against Poland's communist authorities. He won the Nobel Peace Prize in 1983. In 1989, Solidarity toppled Poland's communist regime and Walesa went on to serve as Poland's first democratically elected president, from 1990-95.