Chest pain behind the sternum (breastbone) is a major symptom of heart attack, but in many cases the pain may be subtle or even completely absent (called a "silent heart attack"), especially in the elderly and diabetics. Often, the pain radiates from your chest to your arms or shoulder; neck, teeth, or jaw; abdomen or back. Sometimes, the pain is only felt in one these other locations.

The pain typically lasts longer than 20 minutes and is generally not fully relieved by rest or nitrioglycerine, both of which can clear pain from angina.

The pain can be intense and severe or quite subtle and confusing. It can feel like:

• squeezing or heavy pressure
• a tight band on the chest
• "an elephant sitting on [your] chest"
• bad indigestion

Other symptoms you may have either alone or along with chest pain include:

• Shortness of breath
• Cough
• Lightheadedness - dizziness
• Fainting
• Nausea or vomiting
• Sweating, which may be profuse
• Feeling of "impending doom"
• Anxiety

During a physical examination, the doctor will usually note a rapid pulse. Blood pressure may be normal, high, or low. While listening to the chest with a stethoscope, the doctor may hear crackles in the lungs, a heart murmur, or other abnormal sounds.

The following tests may reveal a heart attack and the extent of heart damage:

• Electrocardiogram (ECG) -- single or repeated over several hours
• Echocardiography
• Coronary angiography
• Nuclear ventriculography (MUGA or RNV)

The following tests may show the by-products of heart damage and factors indicating you have a high risk for heart attack:

• Troponin I and troponin T
• CK and CK-MB
• Serum myoglobin