I also agree with bb252 and Shachi in the respect that this LifeVest Wearable Cardioverter Defibrillator is in fact a Class III medical device. In regards to potential challenges faced while trying to get this device approved, I believe that proving its reliability to be able to successfully detect heart arrhythmias along with not misfiring when the device isn’t needed. In both of these circumstances, the direct action of this device would have a very big impact on the patents quality of life. In addition, I think one of their bigger challenges is making sure this device wouldn’t trigger during normal exercise patterns when heart rates naturally elevate. Lastly, the amount of voltage probably has to be calibrated to how much body fat the patient has, because unlike a traditional pacemaker, the voltage has to travel through the skin, fat, and muscle to successfully reach the heart. Determining this scale of voltage used per person would have probably been a pretty sizeable task.