Cardiac Monitors for the Detection of Atrial Fibrillation Among Patients Diagnosed with a Cryptogenic Stroke

Health Technology Assessment Committee Recommendations

1. Implementation of cardiac monitors (including external loop recorders and implantable cardiac monitors) should be done on a limited basis, informed by the analytical model used in the health technology assessment to determine the most cost-effective and impactful approach.
2. Cardiac Services BC is best positioned to oversee and standardize the current limited implementation of cardiac monitors and, until greater evidence is available to indicate widespread deployment, should ensure there are criteria for equitable use in place.
3. Monitoring needs to include but not be limited to the collection of data on appropriate patient selection, the effectiveness of cardiac monitors in preventing secondary strokes and not just in detecting atrial fibrillation, and the optimal frequency of data readings and the impact that the frequency has on system costs.

Health Technology Assessment Committee Findings

1. While limited by the number of studies, the strength of the evidence identified during the health technology assessment is strong for the determination of the effectiveness of detecting atrial fibrillation. However, limited evidence is available that links the clinical effectiveness of improved health outcomes with cardiac monitoring by the assessed technologies.
   1. External loop recorders and implantable cardiac monitors are effective in detecting atrial fibrillation among patients with cryptogenic stroke.
   2. Evidence is required to establish the link between the effectiveness of monitoring for atrial fibrillation detection and the primary outcome of stroke prevention.
2. None of the assessed technologies are considered cost effective when compared to conventional thresholds for cost-effectiveness.
3. The literature review and direct patient interviews indicated that patient confidence is generally improved when monitoring heart rhythm.
4. Clinicians & other key informants generally expressed support for cardiac monitoring and expected improvements to the quality of life of patients.
5. Insertable cardiac monitors with remote monitoring capabilities may help improve access to those in rural/remote areas of the province compared to external loop recorders that require a physical visit to read the data.
6. Other Canadian jurisdictions have limited use of implantable cardiac monitors, with some being used for indications other than cryptogenic stroke. Several jurisdictions have specific criteria for the use of implantable cardiac monitors, generally being used when all other diagnosis options were inconclusive.