What is the guidance on evaluating ischemia (ischemic evaluation)?

From the Guidelines

For patients suspected of having a stroke or TIA, a comprehensive diagnostic evaluation is recommended, including an ECG to screen for atrial fibrillation and other cardiac conditions, noninvasive cervical carotid imaging, CT or MRI of the brain, and blood tests to gain insight into risk factors for stroke and inform therapeutic goals. This approach is based on the 2021 guideline for the prevention of stroke in patients with stroke and transient ischemic attack from the American Heart Association/American Stroke Association 1. The evaluation should be completed or underway within 48 hours of onset of stroke symptoms to identify the etiology of the stroke and plan optimal strategies for preventing recurrent stroke. Key components of the evaluation include:

• An ECG to screen for atrial fibrillation and other cardiac conditions, as recommended with a Class of Recommendation (COR) of 1 and a Level of Evidence (LOE) of B-R 1
• Noninvasive cervical carotid imaging with carotid ultrasonography, CT angiography (CTA), or magnetic resonance angiography (MRA) to screen for stenosis in patients with symptomatic anterior circulation cerebral infarction or TIA who are candidates for revascularization, also recommended with a COR of 1 and an LOE of B-NR 1
• CT or MRI of the brain to confirm the diagnosis of symptomatic ischemic cerebral vascular disease, recommended with a COR of 1 and an LOE of B-NR 1
• Blood tests, including complete blood count, prothrombin time, partial thromboplastin time, glucose, HbA1c, creatinine, and fasting or nonfasting lipid profile, to gain insight into risk factors for stroke and inform therapeutic goals, recommended with a COR of 1 and an LOE of B-NR 1. In patients with cryptogenic stroke, additional testing such as echocardiography with or without contrast, long-term rhythm monitoring, and tests for inherited or acquired hypercoagulable state may be reasonable, as recommended with a COR of 2a and an LOE of B-R or C-LD 1. Overall, a comprehensive diagnostic evaluation is essential for identifying the underlying cause of the stroke and guiding treatment to prevent recurrent stroke and improve outcomes.

From the Research

Ischemic Evaluation Guidance

The guidance on evaluating ischemia involves various tests and strategies to diagnose and manage ischemic heart disease. The following points highlight the key aspects of ischemic evaluation:

• Ischemic heart disease represents a pathophysiologic continuum consisting of stable angina, unstable angina, non-ST-segment elevation myocardial infarction, and ST-segment elevation myocardial infarction 2.
• The diagnosis of acute myocardial infarction is based on increased or decreased value of cardiospecific troponins with one measure exceeding the 99th percentile upper reference limit, associated with symptoms suggestive for myocardial ischemia, indicative electrocardiogram abnormalities, and evidence of recent myocardial functional impairment or intracoronary thrombosis 3.
• Early mechanical or pharmacological reperfusion should be performed early in ST-segment elevation myocardial infarction within 12 h of symptom onset, whereas fibrinolysis may be considered in all other circumstances 3.
• Patients undergoing primary percutaneous coronary intervention should also receive a combination of double antiplatelet therapy, associated with parenteral anticoagulation, preferably with low-molecular-weight heparin 3.
• Clopidogrel plus aspirin was more effective than aspirin alone in reducing the risk for recurrent stroke, with high-quality evidence, but increased major bleeding events 4.
• Choosing an appropriate test for the evaluation of cardiac ischemia in the inpatient setting requires accurate risk stratification, with two major categories of testing available: stress testing and anatomical testing 5.
• Ischemic evaluations are underutilized in patients admitted with heart failure and a new reduction in left ventricular systolic function, and a focused intervention to increase guideline-concordant care could lead to an improvement in clinical outcomes 6.

Key Considerations

When evaluating ischemia, the following considerations are important:

• Accurate risk stratification is crucial in choosing an appropriate test for the evaluation of cardiac ischemia 5.
• The use of clopidogrel and/or aspirin should be carefully considered, as it can increase the risk of bleeding 2, 4.
• Early mechanical or pharmacological reperfusion is essential in the management of ST-segment elevation myocardial infarction 3.
• Ischemic evaluations can help identify patients with a reversible cause of heart failure, and guideline-concordant care can lead to improved clinical outcomes 6.