Electrically Conductive Hydrogels Usable As Lead Extensions, Apparatus For Delivery Of A Hydrogel Into The Vasculature, and Methods Of Treating Ventricular Arrhythmia With Electrically Conductive Hydrogels Injected In The Venous System

A conductive hydrogel precursor solution cures after injection into the vasculature of the myocardium. The vasculature acts as a mold for the hydrogel and allows for a pacing signal to be conducted across the myocardium and not at a single point like traditional pacing leads. The catheter-based delivery can accurately place the hydrogels into the myocardial veins and can fill the venous tributaries. In situ crosslinking of the hydrogel precursor solution is achieved through several mechanisms, such as redox initiation by mixing a reducing reagent and oxidizing agent after injection. Conductivity is achieved by doping in conductive polymers or other conductive elements such as ionic species, metallic nanoparticles, or graphene nanoplatelets. To ensure long-term conductivity, hydrogel macromers may be synthesized without hydrolytically labile groups such as esters, and the conductive elements may be conjugated directly to the hydrogel matrix.