Heart attack symptoms vary from person to person. Some people even have silent heart attacks (i.e. they don’t even know they’ve had one). The symptoms can range from chest tightness, to crushing chest pain, neck pain, back pain, arm pain, or jaw pain. This can be accompanied by other symptoms, like profuse sweating, nausea, vomiting, difficulty breathing or passing out, again depending on the severity. The people that suffer “sudden death” typically develop a heart rhythm irregularity known as ventricular tachycardia or ventricular fibrillation. That, if it’s quick, is likely to be rather painless. (As an aside, this is the reason for trying to initiate a rapid response and start CPR. If a defibrillator can be used within a few minutes, someone’s heart can be rebooted. If not, well, the consequences are very bad.) On the other hand, if it is a severe heart attack with symptoms as listed above, it can be painful, and the difficulty breathing can be agonizing. If the person dies “slowly”, it can be from the consequences of the heart attack, primarily heart failure and pulmonary edema (fluid in the lungs).