Some might find this little company interesting. Their research is hoping to develop a biological pacemaker. This would benefit pacemaker patients with "special" hearts. Mine thinks it is special so adjusting a PM to suit it's idiosyncrasies is problematic. I gather the idea of using gene therapy is to rebuild electrical pathways and also improve sinus and AV node electrical function.
EIC Transition: PacingCure developing a biological pacemaker - Catalyze
The link via Catalyze, a science centric company that assists science based companies develop and find funding. MsProzac writes reports for companies like this one seeking grants.