A ST-elevation myocardial infarction, known as STEMI, is a severe heart attack requiring immediate medical attention. It occurs when blood flow to a section of the heart muscle is completely blocked, potentially leading to tissue damage or death. Recognizing its urgency is crucial, as swift intervention improves outcomes and limits heart damage.
What is STEMI?
A STEMI results from the complete blockage of a major coronary artery, which supplies oxygen-rich blood to the heart muscle. This blockage commonly arises when an atherosclerotic plaque, a fatty deposit composed of cholesterol, ruptures within the artery. The rupture exposes the plaque’s contents to the bloodstream, triggering a blood clot that can fully obstruct the vessel. This sudden interruption of blood flow starves the heart muscle of oxygen, causing damage.
Individuals experiencing a STEMI often report characteristic symptoms, including severe, persistent chest pain that may feel like pressure, tightness, or squeezing. This discomfort can radiate to areas such as the arms, jaw, neck, back, or upper abdomen. Other common signs include shortness of breath, cold sweats, lightheadedness, nausea, and vomiting. The “ST-elevation” on an electrocardiogram (ECG) confirms a full coronary artery blockage, prompting immediate medical action.
Rapid Treatment for STEMI
The primary objective in treating a STEMI is to rapidly restore blood flow to the affected heart muscle, a concept known as “time is muscle.” Upon suspected STEMI, a swift diagnosis is made using a 12-lead electrocardiogram (ECG), ideally within 10 minutes of first medical contact. Emergency medical services (EMS) personnel can perform and transmit ECGs from the field, allowing hospitals to prepare for the patient’s arrival and activate the STEMI response team.
The preferred treatment to reopen the blocked artery is primary percutaneous coronary intervention (PCI). This procedure involves threading a thin tube, or catheter, through a blood vessel, usually in the wrist or groin, up to the blocked coronary artery. A balloon at the catheter’s tip is then inflated to compress the plaque and clot against the artery wall, followed by stent insertion to keep the artery open. Guidelines recommend performing PCI within 90 minutes if the patient presents to a PCI-capable hospital, or within 120 minutes if transfer to such a facility is necessary.
When immediate PCI is not available within the recommended timeframe, fibrinolytic (thrombolytic) therapy is administered. This involves intravenous medications that dissolve the blood clot blocking the coronary artery. Fibrinolytic agents, such as tenecteplase, are effective when given ideally within the first 3 to 6 hours of symptom onset, though they can be considered up to 12 hours. Following successful fibrinolysis, patients are transferred to a PCI-capable center for angiography within 2 to 24 hours to ensure reperfusion and address arterial issues.
Life After a STEMI
Recovery after a STEMI extends beyond immediate treatment, focusing on regaining physical function and preventing future cardiac events. Cardiac rehabilitation programs play a role in this phase, offering supervised exercise sessions, educational resources, and psychological support. These programs help patients improve physical endurance, manage symptoms like fatigue, and learn about their condition and treatment. They also provide emotional support to help individuals cope with the anxiety or stress that can follow a heart attack.
Medications are a key part of long-term management after a STEMI to reduce the risk of recurrence. Antiplatelet agents, such as aspirin, are commonly prescribed to prevent new blood clots from forming. Statins help lower cholesterol levels, reducing new plaque buildup in the arteries. Beta-blockers are often used to decrease the heart’s workload and regulate heart rhythm, while ACE inhibitors can help lower blood pressure and improve heart function. Adherence to these medications, along with lifestyle adjustments like a heart-healthy diet, regular physical activity, and stress management, are important for sustained heart health.
Preventing a STEMI
Preventing a STEMI involves addressing modifiable risk factors that contribute to coronary artery disease. High blood pressure, elevated cholesterol levels, and diabetes increase the likelihood of plaque buildup and rupture in the arteries. Lifestyle choices also play a role in risk reduction, with smoking being a key factor in heart disease. Obesity and a lack of physical activity also increase risk, highlighting the need for maintaining a healthy weight and engaging in regular exercise.
Adopting a heart-healthy lifestyle is a proactive step in prevention. This includes consuming a balanced diet rich in fruits and vegetables, limiting sodium and unhealthy fats, and engaging in at least 150 minutes of moderate-intensity physical activity per week. Quitting smoking is a highly impactful change an individual can make to reduce their risk. For those with existing medical conditions such as hypertension or diabetes, consistent management through physician recommendations and prescribed medications is an important step to prevent a STEMI.