It's your birthday and you've just enjoyed your favorite dinner (with an extra large helping of mashed potatoes and gravy) and finished off the celebration with a super-sized piece of cake - ala mode, of course! What comes next on the menu is something you didn't order … the worst case of heartburn and indigestion you've ever experienced. Or could it be something more serious?

"Sometimes it's impossible to tell the difference between the symptoms of heartburn, angina and heart attack," cautioned Prediman K. (P.K.) Shah, M.D., director of the Division of Cardiology and the Atherosclerosis Research Center at Cedars-Sinai Medical Center. "There are some useful pointers that might help a person know whether they're having a heart attack or not, but when in doubt, check it out."

Knowing if you have any risk factors that might predispose you to a heart attack is the first important factor to keep in mind, said Shah. "If you smoke, have diabetes, high cholesterol, high blood pressure, are overweight or have a strong family history of heart disease and have any symptom related to the chest or heart, you should be suspicious." Heart attack symptoms include the sudden onset of tightness, pressure, squeezing, burning, or discomfort in the chest, throat, neck or either arm. You should be especially suspicious if these symptoms are accompanied by nausea, vomiting, sweating, shortness of breath or a fainting sensation, Shah warned. "That's when a bell should ring telling you that these symptoms may be indicating a heart attack."

Angina, the most common symptom of coronary heart disease, is chest pain or discomfort that occurs when the heart muscle doesn't get enough blood. The pain, which can also occur in the shoulders, arms, neck, jaw or back, may also feel like indigestion. Confused?

"Generally we recommend that if you think you're having a heart attack, call 9-1-1," said Shah. "It's the safest thing to do. We tell people to err on the side of caution and overreact instead of underreact."

When a heart attack occurs, the blood supply to part of the heart muscle is severely reduced or stopped when one or more of the coronary arteries supplying blood to the heart is blocked. Death or disability can result, depending on how much of the heart muscle is damaged.

Unfortunately, there's no "rhyme or reason" when it comes to predicting the time of the day or circumstances when a heart attack might occur. It could strike in the middle of the night, after a heavy meal, during or immediately after sexual activity or after moderate or heavy physical activity. "Obviously, if you've been diagnosed with coronary heart disease, then any of these symptoms should ring a loud bell," said Shah.

Sometimes the symptoms of reflux or common heartburn related to indigestion can look like a heart attack. If you've had heartburn all your life and the symptoms you're experiencing are identical to those you've had before - and nothing different has occurred - chances are you're experiencing heartburn and not a heart attack. But if the symptoms are something you've never had before and are accompanied by feeling light-headed or sweaty, "then that type of heartburn should be taken more seriously," Shah said. "It could signal that you've having a heart attack."

Shah emphasized that there are many other types of heart disease - he describes them as different "flavors" - that do not produce chest pain yet can be just as life-threatening as a heart attack. Having a regular check-up by a physician when you reach middle age (between 45 and 50) or before beginning a heavy exercise program is essential, he said. "Certain heart conditions can remain hidden and put persons at risk for sudden death. It's important to point out that heart disease isn't just one flavor - there are many different flavors."