@Article{info:doi/10.2196/26519,
author="Lamberigts, Marie
and Van Hoof, Lucas
and Proesmans, Tine
and Vandervoort, Pieter
and Grieten, Lars
and Haemers, Peter
and Rega, Filip",
title="Remote Heart Rhythm Monitoring by Photoplethysmography-Based Smartphone Technology After Cardiac Surgery: Prospective Observational Study",
journal="JMIR Mhealth Uhealth",
year="2021",
month="Apr",
day="15",
volume="9",
number="4",
pages="e26519",
keywords="cardiac surgery; postoperative follow-up; cardiac rehabilitation; postoperative arrhythmias; atrial fibrillation; photoplethysmography; home-monitoring",
abstract="Background: Atrial fibrillation (AF) is the most common arrhythmia after cardiac surgery, yet the precise incidence and significance of arrhythmias after discharge home need to be better defined. Photoplethysmography (PPG)-based smartphone apps are promising tools to enable early detection and follow-up of arrhythmias. Objective: By using a PPG-based smartphone app, we aimed to gain more insight into the prevalence of AF and other rhythm-related complications upon discharge home after cardiac surgery and evaluate the implementation of this app into routine clinical care. Methods: In this prospective, single-center trial, patients recovering from cardiac surgery were asked to register their heart rhythm 3 times daily using a Food and Drug Administration--approved PPG-based app, for either 30 or 60 days after discharge home. Patients with permanent AF or a permanent pacemaker were excluded. Results: We included 24 patients (mean age 60.2 years, SD 12 years; 15/23, 65{\%} male) who underwent coronary artery bypass grafting and/or valve surgery. During hospitalization, 39{\%} (9/23) experienced postoperative AF. After discharge, the PPG app reported AF or atrial flutter in 5 patients. While the app notified flutter in 1 patient, this was a false positive, as electrocardiogram revealed a 2nd-degree, 2:1 atrioventricular block necessitating a permanent pacemaker. AF was confirmed in 4 patients (4/23, 17{\%}) and interestingly, was associated with an underlying postoperative complication in 2 participants (pneumonia n=1, pericardial tamponade n=1). A significant increase in the proportion of measurements indicating sinus rhythm was observed when comparing the first to the second month of follow-up (P<.001). In the second month of follow-up, compliance was significantly lower with 2.2 (SD 0.7) measurements per day versus 3.0 (SD 0.8) measurements per day in the first month (P=.002). The majority of participants (17/23, 74{\%}), as well as the surveyed primary care physicians, experienced positive value by using the app as they felt more involved in the postoperative rehabilitation. Conclusions: Implementation of smartphone-based PPG technology enables detection of AF and other rhythm-related complications after cardiac surgery. An association between AF detection and an underlying complication was found in 2 patients. Therefore, smartphone-based PPG technology may supplement rehabilitation after cardiac surgery by acting as a sentinel for underlying complications, rhythm-related or otherwise. ",
issn="2291-5222",
doi="10.2196/26519",
url="https://mhealth.jmir.org/2021/4/e26519",
url="https://doi.org/10.2196/26519",
url="http://www.ncbi.nlm.nih.gov/pubmed/33856357"
}