Some people experience rapid heart rates not as palpitations, but rather as chest pain. In people with healthy hearts, palpitations may cause a pounding or thumping sensation that can be painful or uncomfortable, rather than the heavy, tight, or squeezing sensation, called angina, usually associated with heart attacks. In people with coronary artery disease, a rapid heart rate can cause angina. How you describe your pain may help your doctor determine whether the chest pain is the result of an abnormal rhythm or angina. In many cases, your doctor may not be sure based strictly on your description, and will probably order an electrocardiogram (EKG, ECG) or further stress testing to evaluate the rhythm or rule out angina.