January 14, 2026European Heart Journal - Digital Health0 citationsOpen Access
Comparison of standard of care and pre-cardioversion heart rhythm monitoring using smartphone PPG (SMARTBEATS-RCT) - a randomized clinical trial
Key Result
Pre-cardioversion monitoring using smartphone PPG reduced same-day cancellations from 23.2% to 4.8% compared to standard care, with a relative risk reduction of 94.7%.
Key Points
- The study aims to evaluate the effectiveness of smartphone photoplethysmography in pre-cardioversion heart rhythm monitoring for atrial fibrillation patients.
- Conducted as a randomized, controlled, single-blinded trial in a tertiary hospital.
- Included adults with persistent atrial fibrillation or atrial flutter scheduled for cardioversion.
- Monitored heart rhythm using smartphone PPG in the intervention group, while the control group received standard care without active monitoring.
- Performed daily overreading of encrypted heart rhythm recordings and simultaneous one-lead ECGs for validation.
- Contacted participants in the intervention group to cancel cardioversion if spontaneous sinus rhythm conversion occurred.
- Among 206 randomized participants, 104 were in the intervention group and 99 in the control group.
- The intervention group had 4.8% same-day cancellations versus 23.2% in the control group (P < .001).
- Spontaneous sinus rhythm conversions led to 1.0% cancellations in the intervention group compared to 18.2% in the control group (P < .001).
- Relative risk reduction (RRR) for cancellations was 94.7% with an absolute risk reduction (ARR) of 17.2%, and the number needed to treat (NNT) was 6.
Structured PICO
Does pre-cardioversion heart rhythm monitoring using smartphone PPG reduce same-day cancellations in adult patients scheduled for cardioversion for persistent atrial fibrillation or flutter?
P
Population
203 adult patients with persistent atrial fibrillation or atrial flutter scheduled for cardioversion, median age 69.7 years, 27.7% female.
I
Intervention
Pre-cardioversion ambulatory heart rhythm monitoring using smartphone photoplethysmography (PPG) with daily overread, plus reminders for anticoagulation adherence. Cardioversion was canceled prior to the procedure day if spontaneous conversion to sinus rhythm was detected.
C
Comparator
Standard of care (no active monitoring prior to scheduled cardioversion).
O
Outcome
Proportion of same-day cancellations of scheduled atrial fibrillation or flutter cardioversions.
Pre-cardioversion monitoring using smartphone PPG significantly reduces resource-intensive same-day cancellations of scheduled cardioversions.
Main Result
Absolute Event Rate: 0% vs 0%
Abstract
Abstract Background Scheduled cardioversion is a common and resource-intensive procedure in rhythm treatment of atrial fibrillation and atrial flutter. Cancellations of cardioversion procedures are common due to spontaneous conversion to sinus rhythm. Purpose The aim of this study was to study the efficacy and feasibility of pre-cardioversion rhythm monitoring using smartphone photoplethysmography as compared to standard of care in scheduled cardioversion of atrial fibrillation. Methods Randomized, controlled, single-blinded study at a single center in a tertiary hospital. Adult patients with persistent atrial fibrillation or atrial flutter scheduled for cardioversion were included. Pre-cardioversion ambulatory heart rhythm monitoring using smartphone photoplethysmography and reminders to support adherence to anticoagulation was applied in the intervention group as compared to standard of care (no active monitoring). Heart rhythm recordings were encrypted and transferred following recording and overread daily. A one-lead ECG recording was made simultaneous to each photoplethysmography recording for validation purposes. In case of spontaneous conversion to sinus rhythm in the intervention group, participants were contacted and cardioversion was canceled. In the control group, no further action was taken in case of rhythm conversion. The primary efficacy outcome was proportion of same-day cancellations of scheduled atrial fibrillation or flutter cardioversions. Results Among 369 contacted patients, 286 responded and 207 accepted participation and attended an inclusion visit, of which 206 were randomized. There were 105 participants assigned to intervention, and 101 assigned to standard of care. Three participants were excluded after randomization due to having a cardiac implantable device, leaving 104 and 99 participants for final analysis in the intervention and control group, respectively. Median age was 69.7 years and 27.7% were female. The participants performed 5226 heart rhythm recordings pre-cardioversion and the median number of daily recordings per participant pre-cardioversion was 2.1. There were 4.8% (5/104) same-day cancellations of scheduled cardioversions in the intervention group compared to 23.2% (23/99) in the control group (P .001). For same-day cancellations due to spontaneous sinus rhythm conversion, the corresponding results were 1.0% (1/104) versus 18.2% (18/99) (P .001), relative risk reduction (RRR) 94,7%, absolute risk reduction (ARR) 17,2 % and number needed to treat (NNT) was 6. Conclusion Pre-cardioversion monitoring using smartphone PPG represents an easy-to-use and highly disseminated digital intervention significantly reducing same-day cancellations.Difference cardioversion cancellations.