Sudden Cardiac Arrest: What is it?
Sudden cardiac arrest is defined as the sudden or abrupt loss of heart function. Sudden cardiac arrest is a life-threatening event that will lead to death (i.e. sudden cardiac death or SCD) if left untreated or poorly managed. Up to 80% of people who suffer SCD have coronary artery disease (CAD), but there are other common and not so common heart conditions that can cause sudden cardiac arrest leading to SCD. The main mechanism of sudden cardiac arrest is believed to be malignant ventricular arrhythmias triggered by cardiac ischemia (i.e. lack of blood flow to the heart) or injured myocardium (i.e. damaged or impaired heart muscle). Sudden cardiac arrest affects people of all ages, ethnicities, and health status, but some people may have signs and symptoms many weeks prior to this catastrophic event and not even know it! It is believed that many people ignore serious warning signs in the weeks, days, and even hours before they collapse due to sudden cardiac arrest. A recent study has investigated that phenomenon. The study investigators tried to identify the early warning signs and symptoms of sudden cardiac arrest, in order to identify high-risk people for early intervention or prevention. There are many classic symptoms associated with “angina” (i.e. chest pain due to a lack of blood flow to the heart), which include the “5 Signs of a Heart Attack”:
- Chest pain or intense pressure with or without extension to your left arm or jaw
- “Dyspnea” or shortness of breath or feeling short-winded either at rest or with minimal exertion
- “Diaphoresis” or excessive and inappropriate sweating
- Unexplained fatigue, nausea, and vomiting
- A sense of “impending doom” or feeling as if you are going to die
These symptoms could signal a heart attack or acute myocardial infarction (MI) and, if you experience any of these symptoms, you should seek immediate
medical attention. However, sudden cardiac arrest is not always due to a heart attack. So in this recent study, the investigators evaluated symptoms from population of patients during the weeks before their sudden cardiac arrest. They identified a list of frequent early warning signs and symptoms, which included:
- chest pain
- “syncope” or losing consciousness unexpectedly and “palpitations” or an abnormal fluttering, thumping feeling in your chest
- ongoing influenza-like symptoms (e.g. malaise, fatigue, nausea, “not feeling well”)
This list is similar to the classic symptoms of a heart attack, but the investigators clearly found some unique differences. These symptoms are worrisome in people who have diabetes, high blood pressure, high blood cholesterol, obesity, or smoke. Additionally, these symptoms are especially worrisome in people with established heart disease (e.g. CAD or heart failure). These symptoms can also be different between men and women, which is a widely-known and appreciated phenomenon. In this recent study men tended to have more chest pain and women tended to have more shortness of breath, lightheadedness, and dizziness. The exact reason for this difference in symptoms between men and women is not known. This is why heart attacks are more often missed in women when compared to men, because their symptoms do not immediately suggest a heart problem initially.
Sudden Cardiac Arrest: What should I do?
A sure sign that you need to head to the emergency room would be severe, sometimes referred to as “crushing,” chest pain in the center or left side of your chest and severe shortness of breath at rest or out of proportion to your activity – especially if these symptoms are accompanied by diaphoresis. Additionally, losing consciousness unexpectedly without warning (i.e. no gradual lightheadedness or feeling dizzy or feeling faint) or losing consciousness while exerting yourself (e.g. walking, climbing, running, playing sports, etc.) are very concerning. In these cases, taking 325 milligrams of aspirin orally and dialing 9-1-1 or contacting emergency medical services (EMS) would be highly recommended. According to this recent study, calling EMS had a survival advantage compared to not calling EMS. Most importantly, do not ignore your symptoms and do not drive yourself to the hospital! Ambulances, or at least family members or friends, can provide a safe way to get to the hospital without putting yourself or others in danger.
So, “sudden” cardiac arrest may not be so sudden or abrupt after all. A high percentage of people have warning signs and symptoms before sudden cardiac arrest, but sadly, they were often ignored. It is important to recognize the above warning signs and symptoms and seek timely medical assistance. Your life may literally depend on it!