Its very difficult to offer a resonable explanation without being able to do an assessment. But, none the less when dealing with anything the more important thing to ask is when is it time to see a liscenced care provider I hope I dont go overboard in answering your question... Where exactly does she feel pain (The heart is not a sensory device)? 1)Does increasing activity increase pain? 2)Is it strictly when she lies on her left side? 3)How is the pain characterized and is pain the only symptom ( IE:Shortness of breath, heartburn )? 4)Does your family have a history of heart Disease? 5) History of CHF? ANSWERS: 1) If she experience greater pain with activity: It must suggest ANGINA (the heart is hurting because it doesnt have enough oxygen *a pre-cursor to a heart attack) An ACTUAL HEART ATTACK or ENDOCARDITIS (inflammation of the soft tissue, its kind of like when your ass-cheeks/thighs rub together and they get chaffed ) All these can be very serious and you should seek medical attention immediately 2) Laying on the left side obviously creates the potential of putting greater pressure on the heart specifically affecting RIGHT ATRIAL pre-load or RIGHT VENTRICAL afterload. Either way about it, the fact that laying on her left side causes pain would say to me that you need to get it checked out because it could again, be a pre-cursor to many other things. Perhaps she has arthrosclerosis, or arteriosclerosis. (the clogging of arteries) -- could potentially be very bad 3) People who have chest pain characterize the symptoms in varrying qualities. Women especially are known for having non-typical symptoms. Such as flank pain or heartburn. ALTHOUGH let me stress that i believe you need to see a physician, I would characterize SHARP, SHOOTING, or INTENSE pain as being much more serious than DULL, Numbing, or GENERALIZED pain. *********laying on the left side could also potentiate heartburn (because of where the stomach is positioned). In all AT-HOME patients like this, trying taking some Tums (calcium carbonate). If it goes away then it sounds like indigestion. If your mom has been perscribed nitrates (NITRO stat), then I would advise taking 1 EVERY 5 minutes x3 doses until pain drops below a 4 on a scale of 1-10. If the pain subsides after taking a nitro, then you should be okay and follow up with your physician in the morning. If she needs to take all 3 I would still goto the ER and get it checked out. 4) A family history of heart disease means that genetically you and your mother both are pre-disposed to a greater chance of heart disease. 5) CHF or Congestive Heart failure is basically when part of the heart doesnt work that well. LEFT SIDED Heart failure is characterized by: gurgling breath sounds (fluid in lungs), shortness of breath, diziness.... RIGHT SIDED Heart Failure is characterized by: Generalized EDEMA-- which is basically fluid leaking into the interstitial compartment--- which basically you would see as swelling of the ankles or feet--- this is usually painless, but can be uncofortable and eventually can lead to pain as the skin can only stretch so far. *********A good rule of thumb is you dont mess around with things like HEART problems, Neurological defecits, strokes, etc etc. GO SEE A PHYSICIAN *Sincerely, Texas Nurse