1. Triage and Initial Diagnostic Evaluation of Transient Ischemic Attack and Non-Disabling Stroke
7th Edition – 2020 UPDATED
- These recommendations (Section 1) pertain to the initial management of patients with a suspected acute transient ischemic attack or acute ischemic stroke who are not candidates for acute thrombolysis or endovascular thrombectomy. For patients with suspected acute stroke that warrants hyperacute assessment to determine eligibility for thrombolysis/endovascular thrombectomy, refer to the current CSBPR Acute Stroke Management recommendations.
- Individuals experiencing acute stroke symptoms/signs should immediately go to an emergency department, ideally by calling 9-1-1 and transport by emergency medical services to rapidly initiate pre-hospital pathways.
- In reality, however, some people experiencing acute stroke symptoms/signs may present to an outpatient setting such as a primary care physician or family health team office, community clinic, or urgent care centre.
- Individuals experiencing symptoms/signs of acute stroke require rapid assessment, diagnosis, and determination of risk for a recurrent stroke. Patients diagnosed with a transient ischemic attack or minor ischemic stroke who are not candidates for hyperacute treatment with intravenous thrombolysis or endovascular thrombectomy may then be prioritized for secondary prevention of stroke assessment and management.
- Ischemic stroke is a heterogenous condition with many different subtypes and causes, and it is beyond the scope of this guideline to address all of them. This section focuses on the diagnostic studies that are relevant to the identification of common conditions (e.g., atherosclerosis, atrial fibrillation) or some uncommon conditions requiring immediate treatment (e.g., bacterial endocarditis).
1.0 Stroke and TIA
1.0 Patients with acute stroke or transient ischemic attack who present to an ambulatory setting (such as primary care) or a hospital should undergo clinical evaluation by a healthcare professional with expertise in stroke care to determine risk for recurrent stroke and initiate appropriate and timely investigations and management strategies.
1.1 HIGH Risk for Recurrent Stroke (Symptom onset within last 48 Hours)
- Individuals presenting within 48 hours of symptoms consistent with a new acute stroke or transient ischemic attack event (especially transient focal motor or speech symptoms, or persistent stroke symptoms) are at the highest risk for recurrent stroke and should be immediately sent to an emergency department (refer to Clinical Consideration 1.1.3) with capacity for stroke care (including on-site brain imaging, and ideally access to acute stroke treatments) [Evidence Level B].
- Urgent brain imaging (CT or MRI) with concurrent neurovascular imaging (e.g., CT angiography [CTA]) should be completed as soon as possible and before discharge from the Emergency Department [Evidence Level B].
- Patients presenting after 48 hours from the onset of an acute stroke or transient ischemic attack event should receive a comprehensive clinical evaluation and investigations as soon as possible by a healthcare professional with stroke expertise [Evidence Level B]. Refer to Section 2.2 for more information on investigations
Section 1.1 Clinical Considerations:
- Referral to a healthcare professional with expertise in stroke care should be considered for patients with a suspected uncommon cause of stroke, including for young stroke patients (e.g., < 45 years)1 ; family history of young-onset stroke; suspected cerebral vasculitis or other intracranial vasculopathy; or suspected hereditary or acquired thrombophilia.
- Patients presenting with symptoms of vertebrobasilar ischemia may present with fluctuating brainstem/cerebellar type symptoms (e.g., diplopia, dysarthria, dysphagia, non-positional vertigo, ataxia; rarely as isolated symptoms) over a longer time course (i.e., more than 48 hours) and can be mistaken for stroke mimics; however, they also require urgent assessment, neurovascular imaging and management as these types of strokes can have a high morbidity. Consultation with a healthcare professional with expertise in stroke care is strongly encouraged.
- Setting: In some regions, urgent/rapid transient ischemic attack clinics are available that have rapid access to diagnostic services, and they may be considered as appropriate referral options for transient ischemic attack and minor stroke patients where available and accessible.
1 Kapoor et al, CJNS 2020
1.2 Brain and Vascular Imaging
- Brain imaging (CT or MRI) and non-invasive vascular imaging (CTA or MR Angiogram (MRA) from aortic arch to vertex) should be completed as soon as possible following acute stroke or transient ischemic attack [Evidence Level B]. .
- CTA of head and neck (from aortic arch to vertex), which can be performed at the time of initial brain CT, is recommended as an ideal way to assess both the extracranial and intracranial circulation [Evidence Level B]. Note: Some facilities may not have CTA readily available and hence the timing and type of vascular imaging will need to be based on available resources and local practice protocols
- Neurovascular imaging is recommended to identify patients with significant symptomatic extracranial carotid artery stenosis (i.e., 50-99% stenosis), which should trigger an urgent referral for potential carotid revascularization [Evidence Level A].
- CTA is the first-line vascular imaging test for stroke/ transient ischemic attack patients. MRA and carotid ultrasound (for extracranial vascular imaging) are reasonable alternatives to CTA as first-line tests for assessment of carotid vessels if CTA is not possible, and selection should be based on availability and patient characteristics [Evidence Level C].
Section 1.2 Clinical Considerations:
- Brain MRI is superior to a head CT scan in terms of diagnostic sensitivity for identifying small ischemic lesions in patients presenting clinically with a transient ischemic attack or minor stroke event, and can provide additional information for guiding diagnosis, prognosis, and treatment decision-making. Decisions regarding MRI scanning should be based on MRI access, availability and timing of appointments. For maximal diagnostic yield, MRI should be completed as soon as possible after the symptomatic event, ideally within 7 days of symptom onset. MRI is particularly useful in lower risk patients with transient symptoms in whom the presence of ischemia would change their management.
- Common scenarios where urgent brain MRI can be valuable include:
- Normal CT head despite symptoms persisting > 24 hours (if DWI-MRI is negative, cerebral ischemia is unlikely).
- Suspected brainstem or cerebellar ischemia (CT head is insensitive for detecting strokes in the posterior fossa due to bone artifact).
- Focal transient symptoms that are clinically atypical for ischemia
1.3 Blood Work
- The following laboratory investigations should be routinely considered for patients with a transient ischemic attack or minor ischemic stroke as part of the initial evaluation:
- Initial bloodwork: hematology (complete blood count), electrolytes, coagulation (aPTT, INR), renal function (creatinine, estimated glomerular filtration rate), random glucose, ALT [Evidence Level C]. Refer to Table 1A for full list of recommended lab tests
- Additional laboratory tests may be completed during patient encounter or as an outpatient, including a lipid profile (fasting or non-fasting); and screening for diabetes with either a glycated hemoglobin (HbA1c), fasting glucose or 75 g oral glucose tolerance test [Evidence Level C]. Refer to Diabetes Canada Guidelines for further information related to glucose testing.
- (NEW FOR 2020): If giant cell arteritis is suspected (e.g., retinal ischemia or headache), ESR and CRP should be measured [Evidence Level C].
- (NEW FOR 2020): Extensive thrombophilia testing for hereditary hypercoagulable disorders is not recommended for routine investigation of a patient with arterial ischemic stroke and should be limited to selected situations (for example, but not limited to unexplained cerebral venous thrombosis; PFO-related paradoxical embolism) [Evidence Level C]..
- If a hypercoagulable state is suspected, consider consultation with a healthcare professional with Hematology or Thrombosis expertise [Evidence Level C].
1.4 Cardiac Studies
1.4 A Detection of Atrial Fibrillation
- Patients with suspected ischemic stroke or transient ischemic attack should have a 12-lead ECG to assess for atrial fibrillation, concurrent myocardial infarction, or structural heart disease (e.g., left ventricular hypertrophy) as potential causes or risk factors of stroke [Evidence Level B].
- For patients being investigated for an acute embolic ischemic stroke or transient ischemic attack, ECG monitoring for 24 hours or more is recommended as part of the initial stroke work-up to detect paroxysmal atrial fibrillation in patients who would be potential candidates for anticoagulant therapy [Evidence Level A].
- For patients being investigated for an embolic ischemic stroke or transient ischemic attack of undetermined source whose initial short-term ECG monitoring does not reveal atrial fibrillation but a cardioembolic mechanism is suspected, continuous ECG monitoring for at least 2 weeks is recommended to improve detection of paroxysmal atrial fibrillation in selected patients aged ≥ 55 years who are not already receiving anticoagulant therapy but who would be potential candidates for anticoagulant therapy [Evidence Level A]. Refer to CSBPR Secondary Prevention of Stroke Module Section 7 for additional guidance in management of patients with stroke and atrial fibrillation, and the Canadian Cardiovascular Society current recommendations on atrial fibrillation.
- (NEW FOR 2020): For patients aged >65 years with ischemic stroke or transient ischemic attack, pulse palpation or heart auscultation or ECG rhythm strip is recommended to screen for undiagnosed atrial fibrillation [Evidence Level B].
1.4 B Echocardiography
- Echocardiography should be considered for patients with an embolic ischemic stroke or transient ischemic attack of undetermined source or when a cardioembolic etiology or paradoxical embolism is suspected [Evidence Level C]. Routine echocardiography is not required for all stroke patients. [Evidence Level C].
- (NEW FOR 2020): For patients aged 60 years or younger who are being investigated for an embolic ischemic stroke or transient ischemic attack of undetermined source, echocardiography with saline bubble study is recommended for detection of a possible PFO if it may change patient management (i.e., in patients who would be potential candidates for PFO closure or anticoagulant therapy if a PFO were detected) [Evidence Level B].
- Contrast-enhanced (agitated saline) transesophageal echocardiography or transcranial Doppler has greater sensitivity than transthoracic echocardiography for detection of right-to-left cardiac and extra-cardiac shunts [Evidence Level B].
1.5 Functional Assessment
- Patients with stroke should be assessed for neurological impairments and functional limitations (e.g., cognitive evaluation, screening for depression, screening for dysphagia, screening of fitness to drive, need for potential rehabilitation therapy, and assistance with activities of daily living) [Evidence Level B]. Refer to Rehabilitation Module for additional information.
- Patients found to have neurological impairments and functional limitations should be considered for referral to the appropriate rehabilitation specialist for in-depth assessment and management [Evidence Level B].
1.6 Virtual Care for Secondary Stroke Prevention (New 2020)
- Secondary stroke prevention services should establish processes and technology to increase and ensure access to services through virtual care delivery mechanisms for patients who do not require in-person visits, and especially patients living in rural and remote settings without local access to healthcare professionals with stroke expertise [Evidence Level C]. Refer to CSBPR Virtual Care Toolkit 2020 for additional information and guidance.
- Clinicians should follow established/validated criteria to determine the best modality for each patient at each encounter based on the purpose and goals for each visit [Evidence Level C]. Refer to Heart & Stroke Virtual Care Decision Framework for additional guidance and criteria.
- Shared decision-making should also take into account patient values, preferences, health goals, medical complexity, social determinants of health, and health needs [Evidence Level C].
Section 1.6 Clinical Considerations:
- Consulting sites and individual clinicians should have triage protocols and local intake criteria in place to ensure patients referred for their services are seen in a timely manner, especially high-risk patients as described in Section 1.1 of this module.
- The use of virtual care for stroke prevention should include decision tools to identify patients who require in-person visits and those who can reasonably be managed through virtual care, and a scheduling mechanism for virtual visits that support a collaborative team approach to care where appropriate and feasible. Refer to Heart & Stroke Virtual Care Decision Framework for additional guidance and criteria.
- A contingency plan should be established to have patients seen in person in a timely way should the need arise following a virtual care encounter. Refer to CSBPR Virtual Care Toolkit 2020 for additional information and guidance
- Virtual care-enabled evaluations of patients for secondary stroke prevention should be modeled on the topics defined in the Post Stroke Checklist and core elements of stroke prevention care. Refer to CSBPR Post Stroke Checklist for additional information and guidance.
- Validated approaches to virtual neurological exams should be followed.
- Barriers to access, equity and utilization should be considered and work-around solutions implemented.
- Ensure processes in place for booking follow-up tests, referrals and other consultations following a virtual care visit.
- Ensure appropriate documentation and communication to other team members who may also be involved in care remotely.
- Encourage patients and their families to acquire home blood pressure monitors where appropriate and provide education or reliable resources on proper use. Mechanisms should be in place for follow-up and management of BP for patients using home BP devices, by either primary care providers or SPS.
- For timely investigations, consider use of prolonged cardiac monitors, if available, that can be sent to patient’s homes and self-applied, then returned by mail.
- Data collection and quality improvement mechanisms should be in place to monitor efficiency, effectiveness and quality of virtual care encounters.
The goal of outpatient management of transient ischemic attack and non-disabling ischemic stroke is rapid assessment and management to reduce the risk of a recurrent, possibly more serious, event.
There is clear evidence that transient ischemic attacks or minor strokes are unstable conditions that warn of high future risk of stroke, other vascular events, or death. The risk of recurrent stroke after a transient ischemic attack has been reported as 4.7 percent within 90 days (Shahjouei et al. 2020), and the risk is “front-loaded”, with 3.8 percent of recurrent strokes occurring in the first two days following initial symptom onset. These improved rates from the previous 20 percent reinforces the importance and benefits of contemporary aggressive management of stroke and transient ischemic attack patients to prevent recurrent events. The seven-day risk of stroke following a transient ischemic attack can be as high as 36 percent in patients with multiple risk factors. Timely initiation of secondary prevention medical therapy and carotid endarterectomy has been shown to significantly reduce the risk of major stroke after an initial transient ischemic attack or non-disabling stroke. A study by the TIARegistry.Org group reported updated rates that were less than half that expected from historical cohorts and could be explained by better and faster implementation of secondary stroke prevention strategies in this cohort through rapid-access transient ischemic attack clinics (N Engl J Med 2016;374:1533-42). Canada has also seen these decreased (Kapoor et al 2020) with emphasis on the need to continue implementation of aggressive secondary prevention strategies to prevent these rates increasing again.
People with lived experience and their families have also expressed the importance for early access to assessment and diagnosis to prevent a recurrent event. They emphasize the need to receive timely education about signs and symptoms of stroke, and clear explanations about the risk for recurrent stroke and the relevance of the time frames for those at different risk levels for recurrence events. The wait time from an initial transient ischemic attack to further investigations can be a stressful time and this should be considered in management planning. They also expressed concerns about potential biases that some women report, especially when presenting with a transient ischemic attack, or fluctuating symptoms.
Education for the public and healthcare professionals (primary, acute and specialists) about the urgency of assessment and management of transient ischemic attack or non-disabling ischemic stroke is critical to reduce the risk of recurrent, potentially more serious events
Systems should be in place for patients and families who require ongoing education and support related to prevention and management of stroke and its associated risk factors.
Education and training for healthcare professionals who work in primary, secondary, and tertiary care settings, to enable the management of patients with transient ischemic attack or non-disabling ischemic stroke in a timely manner. Education should also include content about the heart-brain connection and need to approach care holistically, considering all vascular risk factors
Processes, protocols, and infrastructure in place to enable rapid access to diagnostic tests and expertise for patients with transient ischemic attack or minor stroke in community healthcare settings and acute healthcare facilities
Well-established and accessible stroke prevention clinics, or broader vascular prevention programs available in all communities through traditional or technological means; and referral pathways and promotion of programs for healthcare practitioners to increase timely access. These resources should be listed, easily accessible to primary care physicians and healthcare providers, and updated annually.
Stroke systems of care should develop virtual care service models to improve the accessibility of secondary prevention services for patients in rural and remote locations, and for patients who have difficulty attending in person appointments.
New 2020 – Cost & time of travel can be a barrier to rural & remote residents accessing distant specialty services. Individual’s often decline referrals or fail to attend appointments due to travel time, cost, & adverse weather conditions, especially in winter. Cross-border (inter-provincial & provincial-territorial) virtual care have many challenges with regulatory barriers in terms of how health professions are regulated.
Monitoring, assessment, and improvement of program regarding uptake, adherence, and quality of stroke prevention programs to ensure patients can access effective services. Consideration should be given to community and individual barriers as well as motivators and enablers.
New 2020 – Virtual Care: Governments and organizations should consider ways to ensure that barriers to access and utilization are addressed and mitigated.
For patients who need Holter monitoring as part of their stroke evaluation, home delivery of ambulatory ECG monitors may be an option in some regions to improve patient access to such tests.
- Proportion of acute stroke and transient ischemic attack patients who are discharged alive from an emergency department or an inpatient stay and then readmitted to hospital for any cause within 7 days of index acute stroke discharge (KQI).
- Proportion of patients with transient ischemic attack or non-disabling stroke who are investigated and discharged from the emergency department who are referred to organized secondary stroke prevention services at discharge. (KQI).
- Time from first encounter with medical care (primary care or emergency department) to assessment by a stroke expert (in clinic or other setting).
- Proportion of patients with motor and speech TIAs who have CT head and CTA completed (or other vascular imaging) within 24 hours of presentation.
- Time from first encounter with medical care to brain imaging (CT/MRI); vascular imaging (Doppler of cervical arteries, CTA, or MR angiography); and electrocardiogram.
- Developmental KQI: Proportion of HIGHEST risk transient ischemic attack and non-disabling stroke patients who are investigated and managed within 24 hours in the ED or referred to organized secondary stroke prevention services (KQI)
- Data access and quality with respect to timing of first encounter and referral dates and times.
- Primary care data from physician billing. This should rely on International Classification of Diseases (ICD) codes and not on physician descriptions of diagnoses, as these may be less accurate.
- Measures from other prevention recommendations in this document also apply applicable to this recommendation but are not repeated here.
Health Care Provider Information
- CSBPR: Acute Stroke Management, Neurovascular Imaging
- CSBPR Acute Stroke Management Module: Screening and Assessment Tools for Acute Stroke Severity
- CSBPR Virtual Healthcare Toolkit
- Heart & Stroke: Post-Stroke Checklist
- Heart & Stroke: FAST Signs of Stroke
- Heart & Stroke: 2020 CPR & EEC Guidelines
- Canadian Cardiovascular Society: 2020 CCS/CHRS Comprehensive Guidelines for the Management of Atrial Fibrillation.
- Thrombosis Canada clinical guides
- Diabetes Canada Clinical Practice Guidelines
- Alzheimer’s Association Guideline Index
- Recommendations of the 5th Canadian Consensus Conference on the Diagnosis and Treatment of Dementia
- American College of Chest Physicians (ACCP), Antithrombotic Therapy for VTE Disease: CHEST Guideline and Expert Panel Report.
- American College of Chest Physicians (ACCP) Anticoagulation Guidelines
- Stroke Engine: Canadian Neurological Scale
- Virtual neurological exam examples:
- Hussona, M.A., Maher, M., Chan, D., Micieli, J.A., Jain, J.D., Khosravani, H., Izenberg, A., Kassardjian, C.D., Mitchell, S.B. The Virtual Neurologic Exam: Instructional Videos and Guidance for the COVID-19 era. Canadian Journal of Neurological Sciences, 2020; 00, 1-6. doi:10.1017/cjn.2020.96; Supporting videos
- American Academy of Neurology
- CorHealth COVID-19 Stroke Memo #5 - RECOMMENDATIONS FOR AN APPROACH TO RAMPING UP IN-PERSON SECONDARY STROKE PREVENTION CLINIC SERVICES IN ONTARIO:
- CorHealth: Secondary Stroke Prevention Resources:
- Stroke Prevention Infographic for Primary Care Providers
- Stroke Prevention Clinic Patient Summary
- Depression, Obstructive Sleep Apnea and Cognitive Impairment – DOC Screening Tool
- Heart & Stroke: Signs of stroke
- Heart & Stroke: FAST Signs of Stroke
- Heart & Stroke: Stroke information
- Heart & Stroke: Atrial Fibrillation information
- Heart & Stroke: Your Stroke Journey
- Heart & Stroke: Post-Stroke Checklist
- Heart & Stroke: Risk Factors for Heart Disease and Stroke
- Heart & Stroke: Taking charge of your stroke recovery: 2020 Virtual healthcare checklist infographic
- Heart & Stroke: Canadian Resuscitation and First Aid Guidelines
- Heart & Stroke: Online and Peer Support
- Canadian Partnership for Stroke Recovery – Video Resources
- Stroke Engine
- Canadian Mental Health Association: Bounce Back
Triage and Initial Diagnostic Evaluation of Transient Ischemic Attack and Non-Disabling Stroke Evidence Table and Reference List
- Evidence Table and Reference List 1a: Triage and Initial Diagnostic Evaluation of Transient Ischemic Attack and Non-Disabling Stroke
- Evidence Table and Reference List 1b: Virtual Care
Patients who present with TIA or minor stroke are at increased risk of recurrent stroke, particularly within the first week following the initial event. A systematic review conducted by Giles & Rothwell (2007) pooled the results from 18 studies, consisting of 10,126 patients with TIA. The risk of stroke at days 2 and 7 was 3.1% 5.2%, respectively. Perry et al. (2014) examined stroke risk in 3,906 patients with TIAs admitted to 8 emergency departments over a 5-year period. In this cohort, 86 patients (2.2%) developed subsequent stroke within 7 days, and 132 (3.4%) at 90 days. Purroy et al. (2012) reported similar frequency of recurrent stroke among 1,137 patients admitted to 30 centers in Spain, presenting with TIA. Recurrent events occurred in 2.6% of patients within 7 days and 3.9% within 90 days. Following the first 30 days, the risk of recurrent stroke appears to decline. Mohan et al. (2011) included the results from 13 studies of patients recovering from first-ever stroke who were participants of hospital and community-based stroke registries. The cumulative risks of stroke recurrence were 3.1% at 30 days; 11.1% at one year; 26.4% at 5 years; and 39.2% at 10 years. Callaly et al. (2016) followed 567 participants of the North Dublin Population Stroke Study. The reported cumulative incidence of stroke recurrence was 5.4% at 90 days, 8.5% at one year and 10.8% at 2 years with a 2-year case fatality of 38.6%. These findings highlight the value of assessing patients who present with suspected stroke or TIA according to time since onset of symptoms.
Rapid clinical assessment by stroke specialists and subsequent investigations to differentiate TIA and minor stroke from other potential causes are essential to ensure that secondary prevention strategies can be implemented as soon as possible. Urgent TIA clinics provide such a model of care. The TIAregistry.org project is a prospective registry designed to follow patients presenting with TIA or minor stroke over a 5-year period. Patients were included if the event had occurred within the previous 7 days. The preliminary one-year results, which included 4,583 patients recruited from 61 sites in 21 countries from 1997-2003, indicated that 78.4% of patients were seen by a stroke specialist within 24 hours of the event (Amarenco et al. 2016). Most patients received key urgent investigations before discharge and appropriate treatments were initiated. For example, 5.0% of patients received a new diagnosis of atrial fibrillation, of which 66.8% received anticoagulant therapy before discharge. Carotid stenosis of ≥50% was found in 15.5% of patients, of which 26.9% underwent carotid revascularization before discharge. The one-year estimate of risk of the primary outcome, a composite of death from cardiovascular causes, nonfatal stroke and nonfatal acute coronary syndrome, was 6.2% (95% CI 5.5-7.0%). Estimates of the stroke rate at days 2, 7, 30, 90, and 365 were 1.5%, 2.1%, 2.8%, 3.7%, and 5.1%, respectively. These estimates were much lower than those compared with historical cohorts and were attributed to the widespread establishment of TIA clinics. Rothwell et al. (2007) reported that patients who had immediate access to a TIA clinic (EXPRESS) had a significantly reduced risk of recurrent stroke (2.1% vs.10.3%, p=0.0001), compared with an historical cohort who did not have immediate access to the same care. Patients with immediate access also received their prescriptions sooner (median of 1 vs. 20 days). Lavallée et al. (2007) reported the 90-day risk of stroke for all patients seen at their TIA-SOS clinic was lower than that predicted by their ABCD2 score (1.24% vs. 5.96%).
Atrial fibrillation (AF) is a common arrhythmia, which is associated with an increased risk of ischemic stroke. Following minor stroke or TIA, detecting AF in patients with no previous history is important, particularly in those with a cryptogenic stroke or embolic stroke of unknown source. Once identified, AF can be effectively managed, typically with a switch from an antiplatelet to an anticoagulant. However, AF is under-diagnosed because it is frequently paroxysmal and asymptomatic, and patients do not routinely undergo prolonged screening. AF can be detected using a variety of methods including a12-lead electrocardiogram (ECG), Holter monitoring, event recorders and implantable devices. Low levels of monitoring were highlighted in a study authored by Edwards et al. (2016). The records of 17,398 consecutive patients presenting with first-ever stroke or TIA with motor or speech deficits, without a known history of AF in sinus rhythm, were reviewed and the utilization of ambulatory ECG monitoring within the first 90 days of the event was assessed. A total of 5,318 patients (30.6%) received at least 24-hour Holter monitoring within 30 days of the index event. The numbers associated with more prolonged Holter monitoring were lower; 2,253 patients (12.9%) and 25 patients (0.1%) underwent 48-hr and >60-hr monitoring, respectively within 90 days. Monitoring with event loop recording was conducted in 139 patients (0.8%) within 90 days. A meta-analysis conducted by Sposato et al. (2015) examined the use of outpatient cardiac monitoring following minor stroke or TIA in 4 distinct phases. The results from the studies that initiated investigations during the second ambulatory period (phase 4), using mobile cardiac outpatient telemetry (n=5), external loop recording (n=7) or implantable loop recording devices (n=7), reported an estimated 16.9% (95% CI 13.0% -21.2%) of patients were diagnosed with AF.
Prolonged ECG monitoring using wearable or insertable devices has been shown to be effective for improving the detection of paroxysmal AF (numbers needed to screen range from 8-14), with longer monitoring durations associated with an increased probability of AF detection. A systematic review and meta-analysis (Tsivgoulis et al. 2019) included the results from 2 RCTs (FIND-AF and Crystal AF and 2 observational studies). The outcomes of persons who received prolonged cardiac monitoring (PCM) using implantable cardiac monitoring or ambulatory ECG monitoring, were compared with patients who received conventional (non-PCM) cardiac monitoring. Among persons who received PCM, AF was detected more frequently (RR=2.46; 95% CI, 1.61–3.76), the risk of recurrent stroke and recurrent stroke or TIA during follow-up was significantly lower (RR=0.45; 95% CI, 0.21–0.97 and RR=0.49; 95% CI, 0.30–0.81, respectively) and anticoagulation therapy was initiated more frequently (RR=2.07; 95% CI, 1.36–3.17). In the FIND-AF trial, Wachter et al. (2016) recruited 398 patients, >60 years admitted with acute ischemic stroke, within 7 days of symptom onset, in sinus rhythm at admission and without a history of AF. Patients were randomized to receive prolonged Holter ECG monitoring for 10 days, starting in the first week post stroke, and repeated at 3 and 6 months or standard care (an average of 73 hours of inpatient telemetry plus an average of 24 hours of Holter monitoring). At both 6 and 12 months, detection of AF was significantly higher in the prolonged monitoring group (13.5% vs. 4.5% and 13.5% vs. 6.1%, respectively). The associated numbers needed to screen were 11 and 13. There were no significant differences between groups in stroke recurrence (2.5 vs. 4.5%, p=0.28) or death (3.0 vs. 4.5%, p=0.45). A UK trial (Higgins et al. 2013) that randomized 100 patients with no history of AF and in sinus rhythm, reported that a strategy of 7-day ECG monitoring in the acute phase post-stroke was superior to standard care for the detection of paroxysmal AF (18% vs. 2%; p<0.05). Significantly more patients that received additional monitoring were started on anticoagulants.
Among persons with nonacute stroke, Gladstone et al. (2014), found 30-day ambulatory cardiac event monitor to be superior to repeat 24-hour Holter monitoring in identifying AF in 572 patients aged 52 to 96 years without known AF, who had sustained a cryptogenic ischemic stroke or TIA within the previous 6 months. Atrial fibrillation lasting ≥30 seconds was detected more frequently in persons using the cardiac event monitor (16.1% vs. 3.2%, absolute difference, 12.9%; 95% CI 8.0 to 17.6; p<0.001; number needed to screen= 8). The cardiac event monitor was also more likely to identify cases of AF lasting longer than ≥2.5 minutes (9.9% vs. 2.5%, absolute difference, 7.4%, 95% CI, 3.4 to 11.3; p<0.001). By 90 days, oral anticoagulant therapy had been prescribed for more patients in the intervention group (18.6% vs. 11.1%, p=0.01). Three-quarters of AF cases identified in the intervention group were detected within the first 2 weeks of monitoring.
The clinical and cost-effectiveness of prolonged ECG monitoring are likely greater for patients with estimated good life expectancy and quality of life, and for those with excessive atrial ectopy, enlarged or poorly contracting left atrium, or elevated natriuretic peptide levels. While prolonged post-stroke ECG monitoring improves AF detection, it should be noted that clinical trials have not been powered to determine the effect of prolonged ECG monitoring on the rate of recurrent stroke. Device-detected AF is often brief and subclinical and the minimum duration or burden of device-detected AF that warrants initiation of anticoagulant therapy remains uncertain; therefore, expert opinion varies widely.
It has been estimated that 5% of all people over the age of 65 years, in Canada, have evidence of vascular cognitive impairment (VCI). The reported prevalence tends to be higher in those individuals who have experienced a stroke, with up to 29% developing VCI over 5 years following stroke (Pendlebury et al. 2015). Therefore, patients should be screened at the time of presentation using validated instruments such as the Montreal Cognitive Assessment test (MoCA) or the Mini-Mental State Exam (MMSE).
Laboratory investigations and assessment of physiological variables as part of a patient’s initial evaluation provides important information for patient management. A small case control study found that maintenance of normal physiological variables within the first three days of stroke has a beneficial effect on outcomes post stroke (Langhorne et al. 2000). Blood biomarkers have been shown to correlate with cerebral lesion size and stroke severity (Kisialiou et al. 2012). Ferrari et al. (2010) found that hypertension, diabetes, possible etiology, acute infection and cardiac abnormalities were all independent predictors of deterioration following TIA or minor stroke and recommended immediate diagnostic testing for their identification. Together, these findings suggest a complete evaluation of patients presenting with suspected stroke or TIA is beneficial for predicting risk of recurrent stroke and guiding patient management.
When in-hospital or in-clinic visits are not possible, some prevention interventions can be provided through virtual means, such as the telephone or computer-mediated communication. Virtual care interventions have been shown to effective for cardiovascular risk factor reduction. Monthly phone calls with a health advisor resulted in significantly lower systolic and diastolic blood pressures, and was also associated with significant improvements in diet, physical activity, drug adherence, and satisfaction with access to care, compared with usual care (Salisbury et al. 2016). Mobile health interventions were associated with a significantly reduced HgbA1C compared with the control condition and significantly increased odds of smoking cessation at 6 months (Liu et al. 2017). Digital health interventions including telemedicine, web-based strategies, email, mobile applications, text messaging, and monitoring sensors significantly reduced the risk of cardiovascular events (RR=0.61, 95% CI, 0.46–0.80, p<0.001) (Widmer et al. 2015).