 A message from Little Falls Radio and local physicians of knowing the signs about heart attacks. Every 40 seconds someone in the U.S. has a heart attack. That's nearly 800,000 Americans each year. A heart attack occurs when blood flow to the heart is blocked. The interrupted blood flow can damage or even destroy part of the heart muscle. Signs of a heart attack include pain or discomfort in the jaw, neck, or back, feeling weak or lightheaded, chest pain or discomfort, pain or discomfort in the arms or shoulder, or shortness of breath.