BOSTON (Reuters) - For people over 70, pacemakers that stimulate only one part of the heart are just as effective as newer and more expensive devices that apply electricity to two of the heart’s four chambers, British researchers said.The finding suggested that the benefits of two-chamber pacemakers had been overestimated in older people with a heart condition known as atrioventricular block, according to the team led by William Toff of Britain’s Leicester University.
