One in five patients discharged home after cardiac surgery are likely to have atrial fibrillation episodes during the 30 days post-surgery, Canadian researchers report.

But only a tenth of these patients will be picked up by a usual-care approach to detecting AF, their study shows.

In the study, 336 patients without preoperative AF who had undergone cardiac surgery (median CHA₂DS₂-VASc score of 4, mean age 67, 22% female) were randomised to receive continuous electrocardiogram monitoring with wearable patch-based monitors for 30 days or to receive usual care.

All participants had a CHA₂DS₂VASc score of at least 4, or a score of at least 2 along with risk factors for postoperative AF, or postoperative AF within the first 24 hours after surgery.