From the Guidelines
The workup for ST depression on an electrocardiogram (ECG) should begin with a thorough clinical assessment, including a detailed history and physical examination, and initial evaluation with a 12-lead ECG, cardiac biomarkers, and other tests as needed. The patient's presentation and symptoms will guide the extent of the workup. According to 1, a 12-lead ECG is crucial for detecting acute coronary syndromes, and ST-segment depression is a significant risk indicator for mortality and myocardial infarction.
Initial Evaluation
Initial evaluation should include:
- A 12-lead ECG to assess for ST-segment depression and other signs of ischemia
- Cardiac biomarkers (troponin I or T, preferably high-sensitivity assays) to detect myocardial injury
- Complete blood count, basic metabolic panel, and chest X-ray to assess for other potential causes of symptoms
- Serial ECGs and troponin measurements at 0,3, and 6 hours to detect evolving myocardial injury
Additional Testing
Additional testing should include:
- Lipid profile, hemoglobin A1c, and thyroid function tests to assess for cardiovascular risk factors
- Stress testing (exercise treadmill testing, stress echocardiography, or nuclear perfusion imaging) for patients with concerning findings
- Coronary angiography if high-risk features are present (such as dynamic ST changes, positive biomarkers, or high-risk stress test results)
- Echocardiography to assess ventricular function and rule out structural heart disease
Management
Management should include:
- Aspirin 81-325mg daily
- Consideration of beta-blockers (such as metoprolol 25-100mg twice daily)
- Statins (such as atorvastatin 40-80mg daily) while the workup is ongoing As noted in 1, patients with suspected acute coronary syndromes should receive initial medical treatment that may include aspirin, heparin, beta-blocker, and oral or intravenous nitrates in case of persistent or recurrent symptoms. ST depression can indicate myocardial ischemia, but may also be caused by left ventricular hypertrophy, digoxin effect, electrolyte abnormalities, or other non-ischemic etiologies, making a comprehensive evaluation essential for accurate diagnosis and appropriate treatment.
From the Research
Workup for ST Depression
The workup for ST depression involves several steps, including:
- ECG interpretation: ST depression is a significant finding on an ECG, and its presence can indicate myocardial ischemia or infarction 2, 3, 4, 5.
- Clinical evaluation: Patients with ST depression should undergo a thorough clinical evaluation, including a medical history and physical examination, to identify potential causes of the ST depression 2, 4.
- Laboratory tests: Laboratory tests, such as troponin levels and cardiac enzymes, may be ordered to evaluate for myocardial infarction or other cardiac conditions 2, 4.
- Imaging studies: Imaging studies, such as echocardiography or cardiac catheterization, may be ordered to evaluate the coronary arteries and cardiac function 4, 5.
ECG Findings
ECG findings associated with ST depression include:
- ST-segment depression: This is the primary finding associated with ST depression, and its presence can indicate myocardial ischemia or infarction 2, 3, 4, 5.
- T-wave inversion: T-wave inversion can also be present in patients with ST depression, and its presence can indicate myocardial ischemia or infarction 2, 6.
- QRS changes: QRS changes, such as terminal QRS distortion, can also be present in patients with ST depression 6.
Prognosis and Treatment
The prognosis and treatment of patients with ST depression depend on the underlying cause of the ST depression. Patients with ST depression due to myocardial ischemia or infarction may require aggressive treatment, including reperfusion therapy and anti-ischemic medications 2, 4. Patients with ST depression due to other causes, such as electrolyte imbalances or pericarditis, may require treatment of the underlying condition 2, 5.
Risk Factors
Risk factors for adverse clinical events in patients with ST depression include:
- Presence of ST-segment depression: Patients with ST-segment depression are at increased risk of adverse clinical events, including myocardial infarction and death 2, 3, 4.
- Presence of T-wave inversion: Patients with T-wave inversion are also at increased risk of adverse clinical events, including myocardial infarction and death 2, 6.
- Underlying cardiac conditions: Patients with underlying cardiac conditions, such as coronary artery disease, are at increased risk of adverse clinical events 2, 4, 5.