CHP/PCOR fellow Mark A. Hlatky provides comment for an Aug. 2 New York Times article on mounting concerns about the high cost and possible overuse of implantable cardiac defibrillators as use of the device expands. Hlatky says it is difficult to know where to draw the line as to which patients should, and should not, receive defibrillators. And, he says, there is little incentive for manufacturers to keep the price of the defibrillators down, since physicians generally have little concern for price when choosing a defibrillator for their patients.