Woman holding grey and white Coala Heart Monitor with front up

Late-breaking trial proves the efficacy of Coala as part of stroke management
– Dr Magnusson discusses TEASE-study findings

In the recently published TEASE-study (BMJ Open, Aug 2020) the Coala Heart Monitor was used to evaluate 100 patients after cryptogenic stroke. Patients were recruited from two stroke units that underwent scheduled monitoring twice daily, and when symptoms occurred, for 28 days. The monitoring detected previously undiagnosed atrial fibrillation in 9% of the patients, at a mean of 19.7 days after stroke. Patient compliance to the Coala monitoring protocol exceeded 90%.

The research team recommends a hand-held device like Coala Heart Monitor as the main evaluation tool in the vast majority of cryptogenic stroke cases.

The TEASE-study was led by Dr. Peter Magnusson, cardiologist at the Cardiology Clinic in Region Gävleborg, and with academic affiliations to the Karolinska Institute, Stockholm, and Uppsala University, Sweden.


Dr. Peter Magnusson, cardiologist at the Cardiology Clinic in Region Gävleborg

Tell us about the TEASE-study and why the findings are important?

It’s well known that atrial fibrillation is a contributor of stroke. The objective of TEASE was to assess the yield

of newly diagnosed atrial fibrillation by monitoring cryptogenic stroke patients using the Coala Heart Monitor for 28 days following cryptogenic stroke.

In total 100 patients were monitored from home or in the ward. In nine patients (9%, number needed to screen: 11) atrial fibrillation was diagnosed, proving yet again the need of ECG monitoring after stroke in order to protect them from recurrent stroke by treatment with non-vitamin K antagonists.

The study proves excellent compliance of using the Coala with patients performing on average 90.1%±15.0% of scheduled ECG recordings. This is surprisingly good because these patients recently had a stroke. In fact, this shows that the Coala Heart Monitor can be implemented in this setting of highly vulnerable patients. Thus, in many stroke survivors, this is a feasible approach and they will be potentially protected from recurrent stroke by anticoagulation treatment.

When was AF detected in patients? 

Atrial fibrillation was detected after a mean of 20 days from the index stroke, confirming the need of longer-term ECG monitoring. All patients underwent routine ECG-telemetry in the stroke unit and were then continued evaluated with the Coala after discharge. We believe that it is of uttermost importance to initiate further evaluation shortly after the index case of stroke. Ideally, we propose an approach of continued evaluation with the Coala started even before the complete evaluation is finished.

How do you compare the results of TEASE vs. CRYSTAL-AF study? 

One interesting similarity is that both studies found AF in 9% of cryptogenic stroke patients. In the TEASE study it was found non-invasively within 30-days using a Coala monitor, and in the Crystal-AF study it took 6-months to reach 8.9% by using an invasive insertable cardiac monitor.

Prolonged continuous ECG monitoring or insertable cardiac monitors require substantial resources. Thus, while ECG monitoring over an extended period of time is crucial for stroke survivors, post-discharge Holter monitoring or patches are impractical, ECG data storage is limited, and data interpretation requires considerable resources. Insertable cardiac monitors offer continue monitoring and the clinical implication in short episodes regarding anticoagulation is not clear.

Therefore, we would recommend a hand-held device like Coala Heart Monitor as the main evaluation tool in the vast majority of cases, even though insertable cardiac monitor or other diagnostic approaches can be useful in selected cases. The TEASE study shows the benefit of Coala Heart Monitor in this patient group.

For further questions, reach out direct to Dr. Magnusson on peter.magnusson@regiongavleborg.se