ST-elevation myocardial infarction (STEMI) is a type of heart attack that occurs when there is a complete blockage of a coronary artery, resulting in reduced blood flow to the heart muscle. This causes damage to the heart muscle, and if not treated promptly, can lead to serious complications such as heart failure or even death.
STEMI is diagnosed based on a combination of clinical symptoms, electrocardiogram (ECG) changes, and blood tests. The diagnosis is made when a patient presents with symptoms such as chest pain, shortness of breath, sweating, and nausea, and has ECG changes consistent with myocardial infarction.
The diagnostic criteria for STEMI include:
- Symptoms of ischemia (chest pain or discomfort, shortness of breath, sweating, nausea, or vomiting).
- Persistent ST-segment elevation of at least 1 mm in at least two contiguous leads on the ECG.
- New or presumed new left bundle branch block (LBBB) on the ECG.
- Elevated cardiac biomarkers such as troponin levels.
On the ECG, STEMI typically presents as a persistent ST-segment elevation of at least 1 mm in at least two contiguous leads. Other ECG changes that may be seen include Q waves and T-wave inversion, indicating myocardial injury.
If STEMI is suspected, immediate medical attention is necessary, and the patient should be taken to a hospital equipped to treat heart attacks. Treatment for STEMI includes restoring blood flow to the affected artery as soon as possible, which is usually done by performing a coronary angiogram and subsequent angioplasty with stent placement or thrombolysis if angioplasty is not feasible. Other treatments may include medications to manage pain and prevent complications such as blood thinners and beta-blockers.