Reducing Arrhythmia in Dialysis by Adjusting the Rx Electrolytes/Ultrafiltration, Study B

Inclusion Criteria: * Maintenance hemodialysis therapy for end-stage renal disease * Age 18-85 years (subjects between 18-40 years old will be required to have at least one of the following: history of congestive failure, diabetes, coronary or peripheral vascular disease, or arrhythmia) * \>30 days since dialysis initiation * Ability to provide informed consent * Interdialytic weight gain necessitating an UF rate of ≥13mL/kg/hour of dialysis to achieve the target post-dialysis weight in at least half of the dialysis sessions (≥6 sessions) in the month prior to enrollment Exclusion Criteria: * Expected survival \<6 months-to allow trial completion * Renal transplant, transfer to home or peritoneal dialysis, or to non-study hemodialysis facility anticipated within 6 months * Prisoners or cognitive disability preventing informed consent * Pregnancy. A pregnancy test will be required for women of child bearing potential prior to enrollment. A pregnancy test will not be required for women past the age of child-bearing potential \>55 years old, women with a history of surgical sterilization, or for women \<55 years of age who have not had a menses within the past 12 months * Skin condition, immune dysfunction, history of multiple infections or other condition which increases risk of local infection with ILR placement * Bleeding disorder or anti-coagulation that cannot be reversed for ILR placement * Existing pacemaker, implantable monitor or defibrillator which precludes device placement * Chronic, persistent AF (defined as the presence of persistent AF on all available EKGs at time of recent screening)