$Unique_ID{BRK04337} $Pretitle{} $Title{Wolff-Parkinson-White Syndrome} $Subject{Wolff-Parkinson-White Syndrome WPW Syndrome Preexcitation Syndrome Accessory Atrioventricular Pathways Lown-Ganong-Levine Syndrome Sinus Tachycardia Sick Sinus Syndrome Atrial Ectopic Tachycardia} $Volume{} $Log{} Copyright (C) 1989, 1991 National Organization for Rare Disorders, Inc. 644: Wolff-Parkinson-White Syndrome ** IMPORTANT ** It is possible that the main title of the article (Wolff-Parkinson-White Syndrome) is not the name you expected. Please check the SYNONYM listing to find the alternate names and disorder subdivisions covered by this article. Synonyms WPW Syndrome Preexcitation Syndrome Accessory Atrioventricular Pathways Information on the following diseases can be found in the Related Disorders section of this report: Lown-Ganong-Levine Syndrome Sinus Tachycardia Sick Sinus Syndrome Atrial Ectopic Tachycardia General Discussion ** REMINDER ** The information contained in the Rare Disease Database is provided for educational purposes only. It should not be used for diagnostic or treatment purposes. If you wish to obtain more information about this disorder, please contact your personal physician and/or the agencies listed in the "Resources" section of this report. Wolff-Parkinson-White Syndrome (WPW) is a genetic disorder involving irregularities in the heartbeat (cardiac arrhythmia). Wolff-Parkinson-White patients have an extra conduction pathway in the heart, called the Bundle of Kent, which excessively stimulates the ventricles. Palpitations (sensation of rapid or irregular beating of the heart), weakness, and shortness of breath may occur. Symptoms Symptoms of Wolff-Parkinson-White patients are caused by the Bundle of Kent causing abnormal heartbeats such as atrial flutter, atrial fibrillation, or paroxysmal supraventricular tachycardia. In atrial flutter, atriums of the heart contract (tachycardia) more than the ventricles; atrial fibrillation is a 'twitching' of the atriums instead of regular contractions. This in turn causes the ventricles to respond irregularly. Symptoms that can occur from atrial flutter and fibrillation may include irregular pulse, palpitations (rapid heartbeat), lack of normal skin color (pallor), nausea, weakness, faintness (syncope), and fatigue. Paroxysmal supraventricular tachycardia is a condition in which the heart rate suddenly increases to 100 to 200 beats per minute. A sudden, rapid, regular fluttering sensation and tightness in the chest may occur. Patients may also experience weakness, faintness, palpitations, frequent urination (polyuria), and shortness of breath. Attacks of chest pain (angina) may occur in older patients. Causes Wolff-Parkinson-White Syndrome is inherited as an autosomal dominant trait. (Human traits including the classic genetic diseases are the product of the interaction of two genes for that condition, one received from the father and one from the mother. In dominant disorders a single copy of the disease gene (received from either the mother or father) will be expressed "dominating" the other normal gene and resulting in appearance of the disease. The risk of transmitting the disorder from affected parent to offspring is fifty percent for each pregnancy regardless of the sex of the resulting child.) The normal heart has one conduction pathway (the Bundle of His) that transmits electrical impulses from the small chambers of the heart (the atriums or atria) to the large chambers of the heart (the ventricles). These electrical impulses cause the atriums then the ventricles to contract and relax, pumping blood throughout the body. Wolff-Parkinson-White patients have an additional conduction pathway, the Bundle of Kent, which sends extra electrical impulses from the atriums to the ventricles. These extra electrical impulses disrupt the normal beating of the heart to cause atrial flutter, atrial fibrillation, or paroxysmal supraventricular tachycardia. Affected Population Wolff-Parkinson-White Syndrome is a rare disorder that is present at birth (congenital). It affects males and females in equal numbers, and symptoms can occur at any age. Related Disorders Symptoms of the following heart disorders can be similar to those of Wolff- Parkinson-White Syndrome. Comparisons may be useful for a differential diagnosis: Lown-Ganong-Levine (LGL) Syndrome is a genetic disorder involving irregularities in the heartbeat (cardiac arrhythmia) that are slightly different from Wolff-Parkinson-White. The ventricles receive part or all of their electrical impulses from an irregular conduction pathway instead of from the Bundle of His. If LGL patients have atrial flutter, atrial fibrillation, or paroxysmal atrial arrhythmias, then palpitations, faintness, weakness, and nausea may occur as they do in Wolff-Parkinson-White Syndrome. Sinus Tachycardia is a cardiac arrhythmia that causes the heartbeat to gradually increase to over 100 beats per minute. Sinus Tachycardia may be caused by emotional stress, exercise, infection, and certain drugs. Sick Sinus Syndrome is a cardiac arrhythmia characterized by irregular atrium activity. Excessively slow heart beat (bradycardia) and rapid heart beat (tachycardia) usually occur. Gradual supraventricular tachycardia, atrial flutter, and atrial fibrillation may also occur. Palpitations, weakness, faintness, and nausea are common symptoms. Atrial Ectopic Tachycardia is rapid beating of the heart that usually occurs gradually. It is the result of premature electrical impulses located within the middle layer of the atrium (atrial myocardium). Rapid, regular fluttering sensations and tightness in the chest may occur. Palpitations, weakness, faintness, shortness of breath, and polyuria (increased urination) may also occur. Therapies: Standard The electrocardiogram (ECG) is a diagnostic test for Wolff-Parkinson-White Syndrome. This machine records the changes of electrical impulses that cross the heart. The ECG in Wolff-Parkinson-White patients shows particular abnormalities. Diagnosis may also be made with His Bundle Electrocardiography. Drug therapy, surgical treatment, and external electric shock (DC conversion) may be effective in treating the irregularities in the heart beat of Wolff-Parkinson-White Syndrome. Quinidine and procainamide are antiarrhthymic drugs that may help control atrial flutter, fibrillation, and paroxysmal supraventricular tachycardia (PSVT). PSVT's may also be controlled by cardiac drugs such as digoxin and disopyramide, or by the sympathetic agents metaraminol and phenylephrine. Surgical implantation of a cardiac pacemaker may control the rapid heartbeat in PSVT's. Application of external electric shock (DC conversion) to the body may convert atrial flutter and fibrillation and PSVT's into regular heartbeats. Emergency treatment of PSVT's may also involve lying down, stimulation of gagging or vomiting, Valsalva's maneuver, or carotid sinus massage. Any treatment should be used with extreme caution since it may increase rather than decrease the irregularities in the heartbeat. Radiofrequency current (a less powerful type) is also being used to eliminate tachycardia in Wolff-Parkinson-White patients. Genetic counseling may be of benefit for patients and their families. Other treatment is symptomatic and supportive. Therapies: Investigational The drug Edrophonium, may be helpful in treatment of paroxysmal supraventricular tachycardia (PSVT) in Wolff-Parkinson-White patients, but it has not yet been approved by the Food and Drug Administration (FDA). Researchers are investigating propranolol, a noradrenaline blocking drug, that may be useful in preventing atrial flutter, fibrillation, and PSVT's. Adenosine triphosphate (ATP), a natural molecule in the body used to store energy, is being investigated as a treatment for PSVT's and to prevent extra stimulation of the ventricles by the Bundle of Kent. Flecainide, an antiarrhythmic drug, is also being studied to treat PSVT's in Wolff-Parkinson-White patients. This disease entry is based upon medical information available through June 1991. Since NORD's resources are limited, it is not possible to keep every entry in the Rare Disease Database completely current and accurate. Please check with the agencies listed in the Resources section for the most current information about this disorder. Resources For more information on Wolff-Parkinson-White Syndrome, please contact: National Organization for Rare Disorders (NORD) P.O. Box 8923 New Fairfield, CT 06812-1783 (203) 746-6518 American Heart Association 7320 Greenville Avenue Dallas, TX 75231 (214) 750-5300 NIH/National Heart, Blood & Lung Institute 9000 Rockville Pike Bethesda, MD 20892 (301) 496-4236 For genetic information and genetic counseling referrals: March of Dimes Birth Defects Foundation 1275 Mamaroneck Avenue White Plains, NY 10605 (914) 428-7100 Alliance of Genetic Support Groups 35 Wisconsin Circle, Suite 440 Chevy Chase, MD 20815 (800) 336-GENE (301) 652-5553 References MENDELIAN INHERITANCE IN MAN, 7th ed.: Victor A. McKusick; Johns Hopkins University Press, 1986. Pp. 771. INTERNAL MEDICINE, 2nd Ed.: Jay H. Stein, ed.-in-chief; Little, Brown and Co., 1987. Pp. 375-394. COMPARATIVE QUANTITATIVE ELECTROPHYSIOLOGIC EFFECTS OF ADENOSINE TRIPHOSPHATE ON THE SINUS NODE AND ATRIOVENTRICULAR NODE: A.D. Sharma & G.J. Klein; Am J Cardiol (February 1, 1988: issue 61(4)). Pp. 330-335.