Gettysburg Medical News
The Clinical View
by P.E. Hoffsten, MD
18 October 2006

WHAT IS AN ELECTROPHYSIOLOGY STUDY?

            The patient was a 19-year-old college freshman.  He had always been perfectly healthy and had no medical history.  One afternoon while attending a class, he had the sudden onset of dizziness/unsteadiness associated with nausea and he broke out in a terrible sweat.  Fortunately, the class was almost over and several classmates helped get him to the infirmary where the spell ended.  He said he felt just fine and had no idea of what had happened.  An electrocardiogram was run and demonstrated an abnormality called “Wolff-Parkinson-White” syndrome.  This is a condition in which the person’s heart rate may suddenly go so fast that his heart doesn’t have time to fill. The output of blood from his heart gets so low that he comes very ill, as he had while in class.  Often times the abnormal rhythm that is caused by the Wolff-Parkinson-White syndrome will suddenly return to normal and the person again fills fine as if nothing had happened.  Unfortunately, some individuals with this abnormality can die suddenly and others have these very unpleasant spells more frequently.  The doctor in the infirmary told the patient that the condition could be completely cured after an electrophysiology study.  The patient returned home from college and with his parents came to the clinic to arrange for this study.  He and his parents wondered, “What is an electrophysiology study”? 

            It was explained to the patient and his parents that his young man had an abnormal piece of tissue in his heart which lead to the very rapid heartbeat.  In order to determine just exactly where this abnormal piece of tissue is located, special cardiologists called electrophysiologists pass a wire from the person leg up to the heart.  Using this wire, they can “map” the electrical activity in the heart.  The study can take hours but eventually the abnormal piece of tissue is located.  The wire is then directed over this piece of tissue and a high frequency radiowave is used which destroys the tissue on one little tiny spot in the heart and the person is completely cured.  This is called a radiofrequency ablation.  It is painless and the person does not have to be put to sleep, although some strange sensations may occur during the study. 

            Once the study is completed and the ablation is done, the young man will no longer have this problem ever again.  He can play vigorous athletics or be a pilot with no restrictions.  This is a very gratifying condition to treat and as the treatment is completely curative.

            This type of study and treatment are also used for other heart problems.  There is a condition called recurrent ventricular tachycardia that can be fatal also.  Normally, this can be treated with medications or with an implantable pacemaker-like device called an AICD (automatic implantable cardicac defibrillator).  In some people, the shocks that can come from the AICD can be very bothersome and much too frequent.  When medications cannot suppress the abnormal rhythm called recurrent ventricular tachycardia, an ablation using radiofrequency probes, as described above, can also be used to treat the recurrent ventricular tachycardia.  This condition most commonly occurs after a person has had a myocardial infarct (heart attack) and there is an abnormal irritable area left in the heart from when the heart attack heals.

            The electrophysiologist has additional training over and above the cardiac speciality in heart disease.  There are only three such physicians in South Dakota.  These studies need to be done at the Heart Hospital in Sioux Falls or in Rapid City Regional Hospital. 

            As with most illness, care begins with your local clinic and the healthcare providers there.  It is their job to recognize that there is an abnormality in the rhythm of the heart, get baseline studies done and then eventually refer the patient on to the electrophysiologist for this very special type of study and treatment.