Based on what you write, you may well have recourse. Malpractice is medical negligence, or carelessness--when a a doctor is negligent, he may be liable, or financially responsible, for costs the patient suffers due to the negligence (like the cost of a second operation), or other monetary losses (like lost wages, if you missed work), and even for pain and suffering for disability or life impairment lasting weeks or longer (like losing some motion/use of an arm). Since misconnecting a pacemaker wire would seem to be negligent, this may be malpractice. You should consult with a malpractice attorney to evaluate your potential case.