A cardiac rhythm management system provides an endocardial cardiac rhythm
management lead with an at least partially dissolvable coating at least
partially on insulating portions of the lead body at or near its distal
end. Upon dissolution, the coating promotes tissue ingrowth to secure the
lead in place within fragile vascular structures or elsewhere.
Dissolution of one such coating releases a therapeutic agent, such as a
steroid that modifies the fibrotic scar tissue content of tissue
ingrowth, such that the resulting bond between the tissue and the lead is
weak, so that the lead can be easily extracted if desired. One such lead
includes an insulating elongate body carrying at least. The lead also
includes an at least partially dissolvable coating on an insulating
portion of the peripheral distal lead surface. The coating provides one
or more of a rough surface, a porous surface, or a swollen surface after
being exposed to an aqueous substance.