The Loop by Spry Health performs sleep monitoring and real-time continuous vital sign tracking. It can detect when an episode is coming on (heart-attack, seizure) and warn user. http://spryhealth.com/
Body Guardian Heart by Preventice Solutions
The Body Guardian Heart is a peel-and-apply, wireless, discreet, body sensor that conducts body rhythm monitoring (ambulatoy ECG), average heart rate, average respiratory rate, average activity level. This data is continuously monitored and wirelessly transmitted to a cloud platform for further analysis. http://www.preventicesolutions.com/technologies/body-guardian-heart.html