Previous heart attack
Heart attacks typically cause symptoms such as chest pain, trouble breathing, and dizziness. However, it’s also possible to have a silent heart attack and experience no symptoms at all. An electrocardiogram (ECG or EKG) is a test that measures the electrical activity of your heart. Abnormal patterns of activity suggest that part of your heart may have been damaged from a heart attack or some other heart condition.
Future heart attack
In the United States, one person has a heart attack every 40 seconds. To assess your heart’s health and predict future heart attacks, it’s important to understand how accurate EKGs are for diagnosing a previous heart attack and if they can predict future heart attacks. EKGs can potentially detect a heart attack you had years ago without your knowledge. Abnormal electrical patterns during the test suggest that part of your heart may have been damaged from lack of oxygen.
EKGs are not the sole diagnostic tool for heart attacks. They are best used in combination with other tests such as blood tests and imaging techniques. A study compared the accuracy of EKGs with cardiac MRI and found that while EKGs had good specificity and positive predictive accuracy, they had poor sensitivity and modest negative predictive accuracy for diagnosing previous heart attacks.
To predict future heart attacks, EKGs can uncover abnormalities in the electrical activity of your heart. However, they are most effective when used in combination with other tests, such as a standard 12-lead EKG, coronary calcium scan, C-reactive protein blood test, NT-proBNP blood test, and troponin T blood test. Researchers have found that combining the results from these five tests improves the ability to predict the risk of developing heart disease compared to evaluating blood pressure, cholesterol, diabetes, and smoking history.
Silent heart attack
Silent heart attacks are heart attacks that have few or no symptoms. They are caused by a lack of blood flow to the heart, similar to traditional heart attacks. Symptoms, when present, are often mild and may include fatigue, mild chest pain, and flu-like symptoms. It’s important to be aware that silent heart attacks increase the risk of developing another heart attack or heart failure and may elevate the risk of mortality due to delayed medical treatment.
When to seek emergency care
If you suspect you have had a heart attack, it’s crucial to seek emergency care immediately. Prompt medical treatment can help minimize the damage to your heart. Seek emergency attention if you experience chest pain or discomfort in the center or left side of your chest that lasts more than a few minutes, pain in your jaw, back, or neck, pain in one or both arms or shoulders, shortness of breath, lightheadedness, feeling weak or faint.
Remember, an EKG can assist in identifying a previous heart attack by screening for abnormalities in the electrical activity of your heart. However, it’s recommended to combine EKG results with blood tests and imaging techniques to reduce the chances of a false positive. If you suspect a heart attack, immediate medical attention is essential for better prognosis.