In Wolff-Parkinson-White (WPW) syndrome, an extra electrical pathway between your heart's upper and lower chambers causes a rapid. RELATO DE CASO. Síndrome de Wolff-Parkinson-White associada a comunicação interatrial tipo seio venoso. Patrícia Lopes Moraes; Luíz Márcio Gerken;. PDF | Since the first description of the disease now known as Cardiología al diagnóstico y tratamiento del síndrome de Wolff-Parkinson-White.
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Wolff–Parkinson–White syndrome (WPWS) is a disorder due to a specific type of problem with . These individuals typically do not have fast conduction down the accessory pathway .. Create a book · Download as PDF · Printable version. La Síndrome de Wolff - Parkinson - White (WPW) és una anomalia congènita cardíaca que La síndrome de WPW va ser descoberta l'any per Wolff, Parkinson i White. . E, «[ECG-CapituloSindrome-de-Wolff-Parkinson-White. pdf El. En el tercer caso, con síndrome de Wolff-Parkinson-White asintomático, el episodio de muerte súbita se El Texto completo solo está disponible en PDF.
This process is experimental and the keywords may be updated as the learning algorithm improves. This is a preview of subscription content, log in to check access. Preview Unable to display preview. Download preview PDF. Pre-excited reciprocating tachycardia in patients with Wolff-Parkinson-White syndrome: incidence and mechanism. Paroxysmal atrial fibrillation in the Wolff-Parkinson-White syndrome. The Wolff-Parkinson-White syndrome electrocardiogram: a follow-up study of five to twenty years.
A comparison of the antiarrhythmic effects on AV junctional re-entrant tachycardia or oral and intravenous flecainide acetate. Radiofrequency ablation of supraventricular and atrioventricular tachyarrhythmias. In Santini M, et al. Progress in clinical pacing ; pp.
Effect of proprafenone in Wolff-Parkinson-White syndrome: electrophysiologic findings and long-term follow-up. Atrial fibrillation in the preexcitation syndrome.
Syndrome de Wolff-Parkinson-White et mort subite. Experience with consecutive patients undergoing operation for Wolff-Parkinson-White syndrome.
Effect of exercise on ventricular response to atrial fibrillation in Wolff-Parkinson-White syndrome. Evaluation of noninvasive tests for identifying patients with preexcitation syndrome at risk of rapid ventricular response.
Ventricular fibrillation: a possible mechanism of sudden death in patients with Wolff-Parkinson-White syndrome. Comparison of exercise and ajmaline tests with electrophysiologic study in the Wolff-Parkinson-White syndrome.
Etude de la propafenone injectable et orale dans les rentres nodales et les voies de preexcitation ventriculaire. Wolff-Parkinson-White syndrome: a long-term follow-up of 47 cases. Stress and pharmacological test as methods to identify patients with Wolff-Parkinson-White syndrome at risk of sudden death. Electrophysiologic study in patients with Wolff-Parkinson-White at risk for sudden death. XI World Congress of Cardiology. Wolff-Parkinson-White syndrome: atrial vulnerability and electrophysiologic features in patients with and without atrial fibrillation.
In Attuel P, et al. There are various points in this case that stand out: the lengthened PR interval, the not excessively wide conducted QRS complexes, and the late appearance of conduction through the accessory pathway.
The QRS morphology is very suggestive of conduction by an accessory pathway, but the PR interval is slightly prolonged which is uncommon in a conventional WPW syndrome, in which the PR interval in fact tends to be shortened. This probably is due to a pathway with long conduction times, with poor baseline conductivity and properties of decreasing conduction. The QRS complexes conducted through the accessory pathway last less than ms; given that they are completely pre-excited complexes, a greater width would be expected.
Early penetration of the stimulus conducted through the pathway in the specific conduction system may explain this.
More difficult to explain is the appearance so late in the third decade of life of conduction by accessory pathway. It is logical to think that the histological basis myocardial bridges between the atrium and the ventricle was present from birth and that, therefore, the absence of conduction during these years may be due to the functional incapacity of the pathway to transmit the impulses.
It could even be speculated that, given the great influence of sympathetic activity on this accessory pathway, both its prolonged latency and its actual functional situation could be linked to changes in the autonomous nervous system related to age.
Correspondencia: Dr. Rubio Caballero. Population-based studies have demonstrated a bimodal distribution of symptoms for patients with preexcitation, with a peak in early childhood followed by a second peak in young adulthood.
Pappone et al reported that during a mean follow-up of The mean age of these patients was Compared to others who had persistent conductibility through the AP, these patients were asymptomatic, noninducible, and had longer minimal conduction cycle length through the AP during the baseline EPS. Symptoms range from palpitations to syncope to sudden death.
As in other supraventricular tachycardias, episodes of tachycardia may be associated with dyspnea, chest pain, decreased exercise tolerance, anxiety, dizziness, or syncope. Although syncope is often considered a bad prognostic sign, the evidence is not clear. One study evaluated consecutive patients with WPW syndrome, thirty-six of whom had syncope.
These authors reported that syncope during SVT might, in fact, be caused by a vasodepressor mechanism and not by a rapid rate of tachycardia.
Physical examination demonstrates a fast, regular pulse with a constant intensity first heart sound. The jugular venous pressure waveform is usually constant, but it can sometimes be elevated. The incidence of sudden cardiac death in patients with WPW syndrome has been estimated to range from 0. It is distinctly unusual for cardiac arrest to be the first symptomatic manifestation of WPW syndrome.
APs also commonly occur in patients with congenitally corrected transposition of great vessels. Conversely, the presence of retrograde conduction only in an AP will not be apparent on a surface ECG during sinus rhythm concealed pathway. Numerous algorithms have been described to localize the site of the AP using the axis of the delta wave and QRS morphology. The location of the AP along the AV ring is classified variously into five or ten regions, which can be broadly divided into those on the left and the right of the AV groove.
Distribution along these lines is not homogenous. The positive predictive value of these algorithms is better when the delta wave polarity is included and when algorithms involve fewer than six locations.
Two simple algorithms that include both the delta wave axis and the QRS axis are shown Figure 7.
For the purpose of localization of the APs, delta wave is defined as the first 20 ms of the earliest QRS deflection. QRS alternans is observed in approximately one-third of patients with circus movement tachycardia involving an AP.
Although this phenomenon was previously felt to be strongly predictive of an AP-mediated tachycardia, subsequent studies have revealed that QRS alternans can also be seen in patients with AVNRT at rapid rates.
ST-segment depression may occur during ORT. Although this pattern of ST-segment depression may at first appear strongly predictive of myocardial ischemia, multiple studies have been performed which demonstrate that the presence of ST-segment depression during episodes of narrow complex tachycardia are very unlikely to be predictive of coronary artery disease. Because of this, the threshold to perform further evaluations including nuclear stress tests and cardiac catheterization in these patients would be high.
What are the typical electrophysiologic findings of WPW syndrome?
Electrophysiology study EPS in patients with WPW syndrome can help to confirm the presence of an AP, differentiate this condition from other forms of SVT, and to localize the pathway participating in the tachycardia for ablative therapy.
By definition, if an AP is present and conducting antegradely, some part of the ventricle begins activation earlier than expected, so that the HV interval is less than normal at rest. Because the QRS complex is a fusion complex of conduction down both the AV node and the AP, slowing of conduction down the normal pathway results in an increasing degree of preexcitation.
Eccentric atrial activation with ventricular pacing makes it easy to identify the presence of an AP Figure 8. Figure 8. Eccentric retrograde conduction through the accessory pathway located in left free wall. Note the eccentric activation of the atrium with pacing from the ventricle, with earliest atrial depolarization at the distal CS lead CS Retrograde conduction over most APs is nondecremental.
Hence, in the absence of intraventricular conduction delay or the presence of multiple bypass tracts, the VA conduction time is the same over a range of pace cycle lengths. The exception to this is the slowly conducting decremental posteroseptal pathway found in the permanent form of junctional reciprocating tachycardia, in which the VA conduction time increases with increasing ventricular pacing rate. It is important and often challenging to differentiate retrograde conduction over septal pathway from conduction over the normal AV system.
One maneuver that can make this differentiation is differential pacing ie, pacing from the right ventricular apex and the RV base and measuring the VA conduction time.
Retrograde conduction over the normal AV conduction system is fastest when pacing from the apex because conduction can occur rapidly over the His-Purkinje system. VA intervals are longer when the pacing site is moved from the apex to the base. The converse is true in the presence of an AP, with VA intervals shortest when pacing from the base, closer to the site of pathway insertion than from the apex.
Development of bundle branch block BBB aberration during tachycardia can be useful in determining both presence of and participation of an AP in tachycardia Figure 9.
Because of the small but real risks associated with invasive procedures, EPS is not mandated for risk stratification or ablative therapy.
A 2A designation means that it is reasonable to offer EPS with or without ablation in selected patients after a thorough discussion about the risks and benefits of the procedure.
Several noninvasive and invasive tests have been proposed as useful in stratifying patients for the risk of sudden death.
The detection of intermittent preexcitation—which is characterized by an abrupt loss of the delta wave, normalization of the QRS complex, and an increase in the PR interval during a continuous ECG recording—is evidence that an AP has a relatively long refractory period and is unlikely to precipitate ventricular fibrillation.
The loss of preexcitation after administration of antiarrhythmic drugs such as procainamide or ajmaline has also been used to indicate a low-risk subgroup. These noninvasive tests are generally considered inferior to EPS in the assessment of risk of sudden cardiac death. Because of this, they play little role in patient management at present. When screening studies are performed in patients with asymptomatic preexcitation, a significant proportion of patients demonstrate the presence of one or more features associated with an increased risk of sudden death.
More recent evidence makes a stronger case for use of EPS in risk stratifying all asymptomatic patients with preexcitation. Pappone and colleagues studied two hundred twelve consecutive asymptomatic WPW patients after a baseline EPS over 5 years. After a mean follow-up of More importantly, there were three sudden deaths in the entire population, and all of them occurred in patients in whom AVRT and atrial fibrillation were inducible during EPS.
In a more recent study, Pappone and colleagues examined the role of prophylactic catheter ablation in children with asymptomatic preexcitation. Of the one hundred sixty-five eligible children, sixty were determined to be at high risk of an arrhythmia based on their results of EPS. Of these sixty patients, twenty underwent prophylactic catheter ablation, twenty-seven had no treatment, and thirteen withdrew from the study. Among these twelve patients in the control group, two experienced ventricular fibrillation and one died suddenly.
Santinelli and colleagues published two papers describing the natural history of asymptomatic preexcitation. Among two hundred ninety-three adults with asymptomatic preexcitation followed for a median of 67 months, thirty-one patients Among these patients, the event was classified as potentially life-threatening in seventeen patients.