Final answer:
The primary etiology of cardiac arrest in adults is typically coronary heart disease caused by atherosclerosis, which can lead to myocardial infarction (heart attack). Risk factors such as high LDL cholesterol, hypertension, and smoking contribute to this condition.
Step-by-step explanation:
The primary etiology of cardiac arrest in adults typically relates to underlying heart conditions. Coronary heart disease, resulting from atherosclerosis, is the leading cause of cardiac arrest. Atherosclerosis leads to the narrowing of the arteries that supply blood to the heart muscle, increasing the risk for myocardial infarction (MI), commonly known as a heart attack. An MI occurs when a blood vessel is blocked, preventing oxygen from reaching the heart muscle, which can result in the death of cardiac muscle fibers.
Various risk factors contribute to MIs which may trigger cardiac arrest. These include cardiovascular disease, age, smoking, high levels of LDL cholesterol, low levels of HDL cholesterol, hypertension, diabetes mellitus, obesity, limited physical exercise, chronic kidney disease, excessive alcohol consumption, and illegal drug use. These factors can lead to conditions such as cardiogenic shock, arrhythmias, and valvular heart diseases that can precipitate a cardiac arrest.
Importantly, cardiac arrest and heart attack are not the same; a heart attack may lead to cardiac arrest, but they are distinct events. Cardiac arrest refers to the cessation of normal circulation due to the failure of the heart to contract effectively, requiring immediate medical intervention to restore circulation and prevent further damage.