Pounding Heart Beat

Hi I'm a 20 year old female with no history of heart problems.  Recently I have noticed that with the slightest exertion my heart begins to pound very hard.  The other day my heart rate reached 200 from climbing 2 flights of stairs.  This has been going on for about a week, and when my heart beats this fast and hard I get very drowst and feel like I'm going to faint.  I should probably see a doctor for this problem, but I'm fine unless I exert myself, so if I go to the doctor what would they say since I would probably have no symptoms.  What do you think is wrong with my heart?  Thanks

[Cleveland Clinic, MD]

Dear  Annie,

Thank you for your question. There are many causes of tachycardia  (fast heart beat) and they can be divided roughly into sinus (originating from the sinus node or heart's natural pacemaker) and non-sinus tachycardias.  Nonsinus tachycardias are either  supraventricular (coming from the upper chambers of the heart) or ventricular (coming from the lower chambers of the heart).  Supraventricular tachycardias include:  paroxysmal supraventricular tachycardia, atrial flutter, atrial fibrillation and AV nodal tachycardia. Ventricular tachycardias are more serious in nature and are due to a rapid depolarization of  the ventricles.  

Sinus tachycardia is defined as a heart rate of greater than 100 beats per minute originating from the sinus node.  Sinus tachycardia is classified as either appropriate or inappropriate.  There are many causes of appropriate sinus tachycardia such as exercise, anxiety, panic attacks, dehydration, deconditioning, volume loss due to bleeding or other loss of body fluids, hyperthyroidism, electrolyte abnormalities and many other conditions.

Inappropriate sinus tachycardia can only be diagnosed when all causes of appropriate sinus tachycardia have been ruled out.  It is not clear what causes inappropriate sinus tachycardia but possible etiologies are an increase in the rate at which the sinus node depolarizes and an increased sensitivity to adrenaline.  Once the diagnosis has been made by ruling out all of the potential causes of appropriate sinus tachycardia  there are several treatment options.  If the symptoms are not overly concerning no treatment needs to be done.  There is no increase in morbidity or mortality in persons with this condition and they can expect to have a normal life-span.  For persons in whom the symptoms are unbearable medications such as beta blockers or calcium channel blockers can be used, usually with good results.  In the rare person unable to tolerate medical treatment catheter ablation (burning) of the sinus node with insertion of a pacemaker or surgical removal of the sinus node have been used in the past.  Newer techniques are being developed using catheter ablation to modify and not destroy the sinus node thus avoiding the need for a pacemaker.   This procedure is still in it's infancy and should only be undertaken at a major medical center after consultation with an electrophysiologist.

[Jon]

I dealt with that for 6 years...Still do. Trying to get treatment

[Cleveland Clinic, MD]

It may take a little time but a good cardiologist or electrophysiologist should be able to diagnosis and treat most types of tachycardia.

[Sara L.]

Might check for anemia

[vicki]

I do have been diagnosed with mitral valve prolapse. I am not taking any medication for this at this time.More improtantly, I have a rare disease called Klippel Trenuanary Snydrome. I am taking morophine 3 times a day. My problem that concerns with my heart is I feel that I am having palpations, or pounding heart beats. This wakes me up at night. I have quesitoned my Dr. regarding this and told me that I should have some tests done. I peviously have had a thailum stress test done. I haven't heard the results of them yet. I am wondering if KT is associated and or known to cause heart problems as well. Any information that you have regarding KT would be very much appreicated. My parents have heart problems and both have had open heart sugeries.
Thank you.

[Cleveland Clinic, MD]

Sara - Thanks.  Anemia is in the differential.

Vicki - I'm sorry I don't have any information on KT.  You could check on the website for the national organization of rare diseases.