PHILADELPHIA––New data presented here during Kidney Week found patients undergoing dialysis experienced abnormal heart rhythms at clinically significant rates immediately before, during, and after their dialysis sessions.

The arrhythmias detected over a six-month period were strongly associated with the hemodialysis schedule: patients’ risk for cardiac rhythm problems peaked during the 12-hour interval beginning with each session, decreased for the next 12 hours, and then gradually increased during the remainder of the interdialytic interval (the interval between dialysis sessions).

In the study, 52% of patients experienced atrial fibrillation (AF). Data showed 1,640 AF episodes of six minutes or longer were detected in 22 of 50 patients, and the rate of AF events was nearly four times higher in the 12 hours following dialysis.

Bradycardia (slow heart rates) occurred more frequently than ventricular tachycardia (abnormal and dangerous rapid or chaotic heart rhythms): In the study, 19 of 50 patients had at least one bradycardia episode (with a rate of 26 bradycardia events per patient month); there were only two sustained ventricular arrhythmia episodes during the follow-up. To date, five patients have received pacemakers following the detection of their bradycardia.

“It has been known that patients with end-stage renal disease are at significant risk for cardiac arrhythmias and sudden death. While it has been assumed that fluid and electrolyte imbalances are key contributors to the development of arrhythmias, other factors, including ventricular hypertrophy and cardiac fibrosis, also may exacerbate the underlying risk,” said study co-author James A. Tumlin, MD, FASN, professor, Renal Division at the University of Tennessee College of Medicine. “The data presented today underscore the high prevalence of arrhythmias in ESRD patients, as demonstrated by this technology, and suggest a need for intensive monitoring.”

The MiD Study monitored arrhythmias in 50 hemodialysis ESRD patients at eight sites during a six-month period using the Medtronic Reveal XT ICM, a cardiac monitoring device inserted under the skin of the chest that tracks the heart’s activity for up to three years.