Heartburn and heart attacks are two vastly different things.
"Heartburn" is usually caused by stomach acid getting into the esophagus or throat, causing a burning sensation. It can be caused by medications, certain foods, alcohol, or pregnancy.
Most heart attacks happen when a clot in the coronary artery blocks the supply of blood and oxygen to the heart. Often this leads to an irregular heartbeat --hat causes a severe decrease in the pumping function of the heart. A blockage that is not treated within a few hours causes the affected heart muscle to die.