Medtronic (MDT 0.72%)St. Jude Medical (STJ), and Boston Scientific (BSX 0.39%) are three medical-device makers that pour hundreds of millions of dollars into research and development every year. What follows is a concrete example of how their technological devices save millions of lives.

At the recent mHealth Summit near Washington, D.C., the Fool's Max Macaluso and Rex Moore were able to speak with Robert McCray of the Wireless-Life Sciences Alliance. In this video, Rob explains how Medtronic, St. Jude, and Boston Scientific incorporate wireless technology in their defibrillators, and how it helps doctors and patients alike.

A full transcript follows the video.

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Robert McCray: One example is the big med-device companies: Medtronic (MDT 0.72%), St. Jude (STJ), and Boston Scientific (BSX 0.39%). They all have competing defibrillators that are implanted, that collect information about the patient, and they save lives when there's a heart rhythm issue and they fire off.

Traditionally, a patient with a defibrillator -- an implant -- had to go into a doctor's office, who had a special device to pull information from that defibrillator and determine how the patient was doing, whether some adjustment to meds was required, whether the device itself had some defect.

Starting about eight years ago, all three of the companies put wireless systems in those defibrillators so that they could be read on a bedside monitor in the patient's home. As a result of that, based on one very large retrospective study, the life expectancy of patients with that connected health defibrillator was twice as good after five years as those that didn't have it. That's a concrete example.

They weren't paid for this, by the way. There's no extra reimbursement for this technology. It just made their product better.