Fluid around heart

  My 65-yr-old mother recently had an echocardiogram as part of a general workup in preparation for total hip replacement surgery scheduled later this month.  She was told by her physician that the results of the echo were normal except for "some fluid around her heart".  Apparently it is not too bad because the surgery is still scheduled.  Her physician told her, however, that she should have a follow-up echocardiogram in about 3 months.  My questions are:  what is meant by "some fluid around the heart", what causes it, and what can be done about it?  I should add that my mother has been a 1 pack/day smoker for 40+ years (still is), has been on synthroid for at least 20 years.  Otherwise, except for not exercising, she is quite healthy (very low blood pressure, low cholesterol, normal weight, etc.).  Thank you very much for taking the time to answer my questions.
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Dear Laura:
The pericardium is the sac around the heart.  It normally contains a small amount of fluid.  Several disease states can increase the amount of fluid around the heart.  At a certain point, if there is enough fluid around the heart [a pericardial effusion], it can interfere with the heart filling and beating normally.  This can result in cardiac arrest.  That is why doctors get concerned when they see fluid around the heart.
There are several different causes of fluid around the heart.  Infections [such as tuberculosis], cancers [such as lung cancer], kidney disease and thyroid disease are some possibilities.  Autoimmune diseases such as lupus can also cause pericardial effusions.
Any significant effusion around the heart requires a thorough medical workup to rule out the possibility of serious underlying disease.  Sometimes the cause of an effusion cannot be determined.  Echocardiography [a cardiac ultrasound] can be very useful in following pericardial effusions.
Information provided here is of a general nature.  Specific diagnoses and treatments can only be made by your doctor.  If your mother would like to be seen at the Cleveland Clinic, please call 1-800-CCF-CARE for an appointment with a cardiologist who specializes in echocardiography at Desk F15.

[sarahay]

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