Doctors are implanting high-tech heart defibrillators in thousands of people who probably do not need them, a new study finds. The procedures cost more than $35,000, involve surgery and anesthesia, and may unnecessarily harm some patients. Defibrillators fire an electrical shock to jolt the heart back into a normal rhythm if it starts to beat in a disordered way that can cause sudden death. In people who truly need them, for conditions that can fatally disrupt heart rhythm, defibrillators can be life-saving. Each year, about 100,000 are implanted in the United States. Former Vice President Dick Cheney received one in 2001.
