Detection of Atrial Fibrillation and Secondary Stroke Prevention Using Telemetry and Ambulatory Cardiac Monitoring

Economic evaluation of prolonged and enhanced ECG Holter monitoring in acute ischemic stroke patients

Objective: Atrial fibrillation (AF) is a major cause for recurrent stroke, has severe impact on a patient's health and imposes a high economic burden for society. Current guidelines recommend 24 h ECG monitoring (standard-of-care, SoC) to detect AF after stroke to reduce the risk of future events. However, paroxysmal AF (PAF) is difficult to detect within this period as it occurs infrequently and unpredictably. In a randomized controlled trial (Find-AF_RANDOMISED), prolonged and enhanced Holter ECG monitoring (EPM) revealed a significantly higher detection rate of AF compared to SoC, although its cost-effectiveness has not yet been investigated. Methods: Based on the data of FIND-AF_RANDOMISED, an economic evaluation was conducted. One group received EPM for 10 days after the event, and at 3 and 6 months; the other group received SoC. Healthcare resource use and quality of life (QoL) data were measured at baseline, and after 6 and 12 months. Incremental costs and quality-adjusted life years (QALYs) between both groups were compared. Non-parametric bootstrapping and one-way-sensitivity analyses were performed. Results: A total of 281 patients with healthcare resource use and QoL data for all measurement points were considered in the economic evaluation (complete case analysis, CCA). The CCA yielded nonsignificant 315€ lower mean costs and 0.0013 less QALYs for patients receiving EPM with no statistically significant differences in any cost categories. Sensitivity analyses revealed robust results. Bootstrapping the results indicated moderate probability of cost-effectiveness. Conclusions: EPM yielded reduced not significantly different costs without affecting QoL and may be a useful strategy to detect PAF in acute ischemic stroke patients in time.

External continuous ECG versus loop recording for atrial fibrillation detection in patients who had a stroke

BACKGROUND

Detection of atrial fibrillation (AF) in patients who had ischaemic stroke and transient ischaemic attack (IS/TIA) is recommended. We aimed to compare external loop recording (ELR) against simultaneous continuous ECG recording for AF detection in patients who had acute IS/TIA and determine sensitivity, specificity and positive predictive value of AF detection using ELR. We hypothesised ELR to detect 15% fewer patients with AF than continuous ECG recording.

METHODS

In this prospective cohort study, we included 1412 patients who had acute IS/TIA without prior AF. Monitoring was 48 hours. Primary outcome was AF >30 s. Cardiologist verified AF in continuous ECG was gold standard.

RESULTS

In continuous ECG, 38 (2.7%) patients had AF. ELR automatically categorised 219/1412 patients (15.5%) with AF, including 32/38 (85%) patients with AF in continuous ECG. After cardiologist adjudication of ELR recordings, AF was diagnosed in 57/219 patients, of which 32 (56%) had AF in continuous ECG. For adjudicated AF detection by ELR, sensitivity was 84%, 95% CI (69% to 94%), specificity was 98%, 95% CI (97% to 99%) and positive predictive value was 56%, 95% CI (42% to 69%).

CONCLUSION

Automatic AF detection with ELR results in an AF diagnosis in more than five patients without AF for each patient with AF as verified in continuous ECG. For adjudicated AF detection by ELR, sensitivity was confirmed to 84% and specificity 98%. Automatic ELR as investigated in this study may be considered to rule out AF, but it is not suitable as a single monitoring device for AF screening in patients early after stroke.

TRIAL REGISTRATION NUMBER

NCT02155907.

Finding atrial fibrillation in stroke patients: Randomized evaluation of enhanced and prolonged Holter monitoring--Find-AF(RANDOMISED) --rationale and design

BACKGROUND

Detecting paroxysmal atrial fibrillation (AF) in patients with ischemic strokes presenting in sinus rhythm is challenging because episodes are often short, occur randomly, and are frequently asymptomatic. If AF is detected, recurrent thromboembolism can be prevented efficiently by oral anticoagulation. Numerous uncontrolled studies using various electrocardiogram (ECG) devices have established that prolonged ECG monitoring increases the yield of AF detection, but most established procedures are time-consuming and costly. The few randomized trials are mostly limited to cryptogenic strokes. The optimal method, duration, and patient selection remain unclear. Repeated prolonged continuous Holter ECG monitoring to detect paroxysmal AF within an unspecific stroke population may prove to be a widely applicable, effective secondary prevention strategy.

STUDY DESIGN

Find-AFRANDOMISED is a randomized and controlled prospective multicenter trial. Four hundred patients 60 years or older with manifest (symptoms ≥24 hours or acute computed tomography/magnetic resonance imaging lesion) and acute (symptoms ≤7 days) ischemic strokes will be included at 4 certified stroke centers in Germany. Those with previously diagnosed AF/flutter, indications/contraindications for oral anticoagulation, or obvious causative blood vessel pathologies will be excluded. Patients will be randomized 1:1 to either enhanced and prolonged Holter ECG monitoring (10 days at baseline and after 3 and 6 months) or standard of care (≥24-hour continuous ECG monitoring, according to current stroke guidelines). All patients will be followed up for at least 12 months.

OUTCOMES

The primary end point is newly detected AF (≥30 seconds) after 6 months, confirmed by an independent adjudication committee. We plan to complete recruitment in autumn 2014. First results can be expected by spring 2016.

Surface 12 lead electrocardiogram recordings using smart phone technology

IMPORTANCE

AliveCor ECG is an FDA approved ambulatory cardiac rhythm monitor that records a single channel (lead I) ECG rhythm strip using an iPhone. In the past few years, the use of smartphones and tablets with health related applications has significantly proliferated.

OBJECTIVE

In this initial feasibility trial, we attempted to reproduce the 12 lead ECG using the bipolar arrangement of the AliveCor monitor coupled to smart phone technology.

METHODS

We used the AliveCor heart monitor coupled with an iPhone cellular phone and the AliveECG application (APP) in 5 individuals.

RESULTS

In our 5 individuals, recordings from both a standard 12 lead ECG and the AliveCor generated 12 lead ECG had the same interpretation.

CONCLUSIONS

This study demonstrates the feasibility of creating a 12 lead ECG with a smart phone. The validity of the recordings would seem to suggest that this technology could become an important useful tool for clinical use. This new hand held smart phone 12 lead ECG recorder needs further development and validation.