Her eyes heavy, vision blurring, the world around Mary Darby slides out of focus. It's all going dim. Surrounded by people charged with her well-being and with her best interests top-of-mind, she can feel her conscious self letting go as she slips into the darkness. She is leaving this moment. But she is not worried. She is calm. Relaxed even, at peace with the confidence that not only will she return but when she does, she’ll be better than she is right now. When she finally does join us again — three weeks later — she awakes to a world that has change for her in ways she never imagined and with no idea of all that she and those who care for her have endured. 'I do feel really lucky just to be alive,' she said. 'When I went in for surgery (to repair a weakened mitral valve that was failing to close correctly), I knew there was going to be a risk, but I honestly didn’t think anything was going to happen.' These are the weeks of Mary Darby's life that she will never know. That they led to days she’ll forever cherish and the return of a calm, relaxed even, that comes with the reassurance that her doctors can see how her heart is working thanks to her Gallant ICD — a small implantable cardiac defibrillator in her chest that monitors the heart's ebbs and flows — sharing important data through her myMerlinPulse app (available for iOS and Android) via Bluetooth. And so, it turns out, she was right not be worried after all.