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DictionarySeesyndromeWolff-Parkinson-White syndrome
Wolff-Parkinson-White Syndrome DefinitionWolff-Parkinson-White syndrome is an abnormality in the electrical functioning of the heart which may cause rapid heart rates. The abnormality affects the electrical signal between the atria and ventricles.DescriptionBlood is circulated through the heart and body by a muscular pump and valve system involving the atria and ventricles. The right atrium receives oxygen-lacking blood returning to the heart from the body. The blood is passed from the right atrium into the right ventricle, which contracts and sends blood out to the pulmonary artery. The pulmonary artery sends the blood into the lungs, where carbon dioxide is removed, and fresh oxygen is added. The left atrium receives blood with oxygen from the lungs and passes this arterial blood to the left ventricle, where it is emptied into the aorta, the main artery of the heart.These functions are directed by electrical signals within the heart. In patients afflicted with Wolff-Parkinson-White syndrome, an abnormal pathway exists that causes additional electrical signals to pass between the atria and ventricles, possibly causing rapid heart rate.Causes and symptomsCongenital heart disease may contribute to this and other arrhythmias. Ebstein's anomaly, a congenital heart defect that involves displacement of the tricuspid valve, located on the right side of the heart, is one known cause of Wolff-Parkinson-White syndrome. This anomaly allows blood to flow via the small hole to the other side of the heart. Often, there is no known cause for Wolff-Parkinson-White syndrome. Many people with the syndrome have no symptoms. On the other hand, some people experience temporary rapid heartbeat due to certain drugs, smoking, and anxiety.DiagnosisElectrocardiography (ECG) is used to diagnose Wolff-Parkinson-White syndrome, and other cardiac arrhythmias. A trained physician, normally a cardiologist, can recognize patterns of electrical conduction. With this syndrome, the extra pathway will show a pattern different from those of normal conduction. If no irregular patterns show on the ECG, the patient may be sent home with a 24-hour heart monitor, called a Holter monitor, which will help detect intermittent occurrences. Other studies, such as the cardiac electrophysiologic study (EPS), may be ordered to pinpoint the location of the accessory pathway, and to determine a course of treatment.TreatmentVarious drugs may be used to treat Wolff-Parkinson-White syndrome, as well as other cardiac arrhythmias. The purpose of these drugs is to slow the electrical signals and excitation of heart muscles. As some of these drugs may have side effects, including the rare production of new or more frequent arrhythmias, the patient should be carefully observed. Ablative therapies may be accomplished with radio-frequency or cardiac catheters to cut through the tissue which is causing the abnormal electrical signals.At one time, only open heart surgery was used, but the procedure can be done now with local anesthesia in a special cardiac laboratory. In some cases, surgery may still be recommended to treat Wolff-Parkinson-White syndrome. Young people with this syndrome may be treated more successfully with surgery, rather than enduring a lifetime of drug treatments, or the possible threat of sudden cardiac death.Alternative treatmentA provider may teach patients methods to help control heart rate. Relaxation techniques, acupuncture, botanical medicine, and homeopathy can all be helpful supportive therapies.PrognosisMost patients with this syndrome can lead normal lives, even with episodes of tachycardia. In many cases, the syndrome is secondary to the underlying congenital heart defect. However, Wolff-Parkinson-White syndrome can cause sudden cardiac arrest in certain instances.Key termsAblative — Used to describe a procedure involving removal of a tissue or body part, or destruction of its funtion.Arrhythmia — Irregular heart beat.Electrocardiograph (ECG) — A test of a patient's heartbeat that involves placing leads, or detectors, on the patient's chest to record electrical impulses in the heart. The test will produce a strip, or picture record of the heart's electrical function.Tachycardia — Rapid heart rate, defined as more than 100 beats per minute.PreventionIf the syndrome is not due to congenital heart disease, the patient may try avoiding behaviors which lead to arrhythmia, such as elimination of caffeine, alcohol, cocaine, and smoking.ResourcesOrganizationsAmerican Heart Association. 7320 Greenville Ave. Dallas, TX 75231. (214) 373-6300 or (800) 242-8721. inquire@heart.org http://www.americanheart.org.National Heart, Lung and Blood Institute. P.O. Box 30105, Bethesda, MD 20824-0105. (301) 251-1222. http://www.nhlbi.nih.gov.Wolff-Parkinson-White syndrome [woolf´pahr´kin-sun hwīt´] the association of tachycardia" >paroxysmal tachycardia (or fibrillation" >atrial fibrillation) and preexcitation. The electrocardiogram displays a short P–R interval and a wide QRS complex that characteristically shows an early QRS vector (delta wave). There is a tendency towards premature tachycardia" >supraventricular tachycardia. Called also anomalous atrioventricular excitation.concealed W.-P.-W. s. the condition in which an pathway" >accessory pathway is present but is capable of retrograde conduction only. The electrocardiogram is normal and the patient is prone to tachycardia" >paroxysmal supraventricular tachycardia but is not in danger of excessively rapid heart rates or sudden death should atrial fibrillation develop.latent W.-P.-W. s. a heart abnormality in which there is an pathway" >accessory pathway through which conduction would be possible in either direction but for some reason does not take place. The PR and QRS complexes are normal, but there is a tendency to develop premature tachycardia" >supraventricular tachycardia. If fibrillation" >atrial fibrillation develops, atrioventricular conduction will proceed across the accessory pathway and result in an extremely rapid, irregular rhythm.Wolff-Par·kin·son-White syn·drome (wūlf park'in-son wīt), [MIM*194200] an electrocardiographic pattern sometimes associated with paroxysmal tachycardia; it consists of a short PR interval (usually 0.1 second or less; occasionally normal) together with a prolonged QRS complex with a slurred initial component (delta wave). Synonym(s): preexcitation syndrome Wolff-Par·kin·son-White syn·drome (wūlf park'in-son wīt), [MIM*194200] an electrocardiographic pattern sometimes associated with paroxysmal tachycardia; it consists of a short PR interval (usually 0.1 second or less; occasionally normal) together with a prolonged QRS complex with a slurred initial component (delta wave). Synonym(s): preexcitation syndromeA cardiac conduction disorder in which the sinoatrial impulse travels directly to the AV node or anomalously via the more rapid Kent’s bundle, resulting in premature ventricular contractions and increased susceptibility to supraventricular paroxysmal tachyarrhythmias EKG Short PR interval—< 0.1 sec—a slur on the upstroke of the R or on the downstroke of an S wave or delta wave, prolonged QRS complex, often ST-T changes Management Cardioversion, procainamide, lidocaine or radiofrequency ablation of accessory AV pathwayWolff-Parkinson-White syndrome Preexcitation syndrome Cardiology A conduction disorder with ↑ susceptibility to supraventricular paroxysmal tachyarrhythmias, in which the sinoatrial impulse travels directly to the AV node or anomalously via Kent's bundle, which is more rapid, resulting in PVCs EKG Short PR interval–< 0.1 sec, a slur on the upstroke of the R or on the downstroke of an S wave or delta wave, prolonged QRS complex, often ST-T changes Management Cardioversion, procainamide, lidocaine or radiofrequency ablation of accessory AV pathwayWolff-Par·kin·son-White syn·drome (wulf'pahrk'in-sŏn-wīt' sin'drōm) An electrocardiographic pattern sometimes associated with paroxysmal tachycardia; it consists of a short P-R interval (usually 0.1 second or less; occasionally normal) together with a prolonged QRS complex with a slurred initial component (delta wave). Synonym(s): preexcitation syndrome. Wolff-Parkinson-White syndrome A heart disorder caused by an abnormal band of conductive tissue that can by-pass the controlling node, the atrio-ventricular node, between the upper and lower chambers. The result can be a kind of feed-back oscillator that may produce fatally rapid heart rates. Treatment is by drugs, such as AMIODARONE or DISOPYRAMIDE to slow the heart. (Louis Wolff, American cardiologist, b. 1898, Sir John Parkinson, b. 1885, English cardiologist; and Paul Dudley White, 1886–1973, American cardiologist).Parkinson, Sir John, English cardiologist, 1885–. Wolff-Parkinson-White syndrome - see under Wolff, Louis
White, Paul Dudley, U.S. cardiologist, 1886-1973. Bland-White-Garland syndrome - see under Bland-ELee-White method - see under Lee, Roger IMcGinn-White sign - see under McGinn, SylvesterWolff-Parkinson-White syndrome - see under Wolff, Louis
Wolff, Louis, U.S. cardiologist, 1898-1972. Wolff-Chaikoff block - blocking of the organic binding of iodine and its incorporation into hormone caused by large doses of iodine. Synonym(s): Wolff-Chaikoff effectWolff-Chaikoff effect - Synonym(s): Wolff-Chaikoff blockWolff-Parkinson-White syndrome - an electrocardiographic pattern sometimes associated with paroxysmal tachycardia. Synonym(s): preexcitation syndromeAcronymsSeeWPW |