Most medical devices that have not been adequately tested are ending up inside patients’ bodies, some of the devices are not safe, an investigation has revealed. The devices include heart pacemakers, rods to correct spines, and artificial knees and hips. The investigation found implants that had failed in baboons, or were tested only on pigs and dead bodies, were coming onto the market. The industry says it has transformed millions of lives for the better. BBC Panorama has been working with the International Consortium of Investigative Journalists and 58 media organisations around the world including The Guardian newspaper and the British Medical Journal. The investigation found a lax system of regulation in Europe that allows companies to “shop around” dozens of safety organisations until one of them approves their product. It also found that doctors can be left in the dark about the true risk of treatments they are recommending to their patients. Maureen McCleave, 82 from Essex, was the first person in the UK to be fitted with the “Nanostim” pacemaker because of an irregular heartbeat. Pacemakers are life-saving implants that deliver electrical pulses to the heart to keep them beating regularly. Traditional ones have leads from a battery to the heart that deliver the electrical pulse, but the cables can break. The Nanostim was the first leadless pacemaker that sat inside the heart. Maureen said she was “over the moon” to be the first and felt like a “good guinea pig” when she was implanted with the device at Bart’s hospital in London. “I was so grateful that I’d been chosen, because it sounded too good to be true.” But three years after it was fitted, the battery in Maureen’s Nanostim failed and surgeons could not get it out. She now has a traditional pacemaker keeping her alive. The Nanostim is still sitting inside her heart. She says: “I don’t like the thought I’ve got a piece of metal or whatever in my heart that’s doing nothing and it’s just laying there.” Maureen was not alone – a number of batteries failed and parts fell off inside patients. The pacemaker was withdrawn for safety reasons. At least two people died and ninety events were recorded in which patients were seriously harmed by the device. The Nanostim heart pacemaker was turned down by safety bodies in Germany because of a lack of evidence. Yet it was approved by the British Standards Institute in the UK.