Former US vice-president Dick Cheney has revealed that his heart implant was altered to prevent terrorists from hacking into it.

Mr Cheney, who was former president George W Bush's right-hand man in the "war on terror," has had a long history of heart troubles.

Prior to his heart transplant nearly two years ago, Mr Cheney underwent a series of life-saving procedures, including an implanted defibrillator.

But his doctor, cardiologist Jonathan Reiner, had the device's wireless function disabled when it was replaced in 2007 so that terrorists could not trigger a fatal shock to his heart.

"I was aware of the danger... that existed... I found it credible," Mr Cheney told CBS television.

"I know from the experience we had and the necessity for adjusting my own device, that it was an accurate portrayal of what was possible."

Mr Cheney had five heart attacks that required multiple angioplasties and catheerisations, along with a quadruple bypass operation. His first heart attack took place more than 35 years ago.

But the man who was a the heart of the war on terror launched by the US in the wake of the September 11, 2001 attacks insisted that his health concerns never got in the way of his job.

Mr Cheney not only played a major role in the wars in Iraq and Afghanistan but also in terrorist surveillance programs, harsh interrogation tactics used on terror suspects and wiretapping.

He denied that the stress he endured while serving as vice president during all eight years of the Bush administration from 2001 to 2009 caused or exacerbated his health concerns.

"I simply don't buy the notion that it contributed to my heart disease," Mr Cheney said.

"In fact... getting back to work... was important enough that I, in fact, kept them separate... I always did what I needed to do in order to deal with the health crisis in the moment."

Mr Cheney said that despite being aware of numerous studies showing a significant link between severe heart disease and memory loss, depression and hampered decision-making, he was not worried about it and was not counselled on it either.

A blood test result seen on the very morning of 9/11 showed a surge of potassium in the vice president's blood, a potentially fatal condition known as hyperkalemia.

As Dr Reiner watched television coverage of the attacks on New York and the Pentagon and the crash of a hijacked plane in Pennsylvania, he said he thought: "Oh great, the vice president is going to die tonight from hyperkalemia."

Mr Cheney said that thanks to his treatment, he feels "fantastic" and has no real physical limits at 72.

"I fish. I hunt... I don't ski, but that's because of my knees, not my heart. So, it's been a miracle," he said.

AFP