What is the typical sign of impending heart attack?

The typical signs of an impending heart attack include chest pain or discomfort, which may feel like pressure, squeezing, or fullness. Other common symptoms are shortness of breath, pain or discomfort radiating to the arms, back, neck, jaw, or stomach, and cold sweats, nausea, or lightheadedness. It's important to seek immediate medical attention if these symptoms occur.