Under pressure after malfunctions in at least 45 implanted defibrillators, including two that are suspected in patient deaths, Guidant Corp. on Friday recalled nearly 50,000 of the devices worldwide. For the Indianapolis-based company - its stock price dropped nearly 2% on the news - the recall means a financial blow as it prepares to be acquired by health giant Johnson & Johnson. For many patients, it means surgery to replace suspect devices. Implanted defibrillators monitor the heart and deliver electrical jolts as needed to correct potentially lethal irregularities in the heartbeat. The problem, Guidant said, was that the devices could, without warning, develop a short circuit that would prevent them from delivering the shock when needed. Like many similar devices, the defibrillators are implanted close to the skin, making replacement relatively simple. And the models being recalled are mainly older versions that will soon need replacement anyway. Still, "it's a big problem and it's going to be a very expensive problem for the company," said Dr. Kelly Tucker, a cardiologist with the Orange County Heart Institute in Orange. "But it's not insurmountable. As long as we can take care of the patients, that's our concern." --More 2345 Local Time 2045 GMT