According to research which was presented at the 2011 American Heart Association’s Scientific Sessions, some heart patients with 
implanted cardioverter defibrillators (ICDs) were likely to suffer from sexual related problems due to their heightened fear of the ICD delivering a shock during sex. ICD is a device that delivers a shock the moment it detects a irregular heartbeat that it deems dangerous.
Men were more likey to feel the effects of mild erectile dysfunction due the anxiety caused by this fear but both women and men had lower sexual function scores due to shock related anxiety.
One way to help heart patients with ICD’s who feel apprehensive about this problems is to give appropriate counselling, both before and after the implanting of the device. This will help alleviate the stress levels that these individual feel which is the main cause of them suffering from sexual dysfunction. So if you are one of those patients who are facing this problem, then consult with your doctor or a qualified sexologist to get guidance on how not to let the fear of the shock take away the pleasure of sex from your life.
You can read more about this research in this article here.