2. Wolff-Parkinson-White Syndrome-An Overview
In 1930, Louis Wolff, Sir John Parkinson, and Paul Dudley
White published an article describing 11 young
patients who suffered from attacks of palpitation
associated with an electrocardiographic pattern of
short PR interval and discovered the phenomenon
that later called the WPW syndrome.
3. Definition:
Wolff-Parkinson-White syndrome is characterized by documented
SVT or symptoms consistent with SVT in a patient with ventricular pre-
excitation during sinus rhythm.
(Ref: 2015 ACC/AHA/HRS guideline for the management of adult patients with SVT)
Wolff-Parkinson-White Syndrome-An
Overview
4. Electrical conduction from the atria to the
ventricles can occur via the normal AV
nodal system and also the accessory
pathway simultaneously.
This leads to the creation of the slurred
upstroke, or delta wave, seen on the
surface ECG lead and denoted by arrows in
the tracing seen here.
5. Frequency…
Delta waves detectable on an ECG have been reported to be present in
0.15% to 0.25% of the general population.
Wolff–Parkinson–White syndrome is more common in men than in
women.
Among those with the Wolff–Parkinson–White syndrome, 3.4 percent
have first-degree relatives with preexcitation.
The familial form is usually inherited as a mendelian autosomal dominant
trait.
About 7% to 10% of patients have associated Ebstein’s anomaly and more
likely to have multiple accessory pathways.
6. Clinical Presentation…
50% to 60% of patients report symptoms such as palpitations,
anxiety, dyspnea, chest pain or tightness, and syncope.
In 25% of the cases, the disease will become asymptomatic over
time.
Those patients older than 40 years whose disease has been
asymptomatic are likely to remain symptom free.
7. INVESTIGATIONS…
ECG Criteria for diagnosis:
(1) PR interval is short, typically < 120 milliseconds.
(2) QRS complex exceeds 120 milliseconds, with some leads
showing the characteristic slurred upstroke known as a delta wave and
a normal terminal QRS portion.
(3) The ST-T segment is directed opposite to the delta wave and
QRS vectors.
8. Localization of accessory pathway….
Type A: Has a large R wave in lead V1. It is due to a left-sided
accessory pathway, which permits pre-excitation to the postero-basilar
segment of the left ventricle.
Type B: This type has an S wave in lead V1 and is due to a right-
sided accessory pathway.
9. Dominant R wave in V1 — this pattern is known as “Type A” WPW and
is associated with a left-sided accessory pathway.
10. Dominant S wave in V1 — this pattern is known as “Type B” WPW and
indicates a right-sided accessory pathway.
12. Indication for electrophysiological testing is a decision to undergo catheter
ablation or less frequently, diagnostic study for risk stratification.
Electrophysiological studies utilize the placement of a decapolar catheter to
the coronary sinus and three quadripolar catheters to the high right atrium,
right ventricular apex and His bundle region.
13. MANAGEMENT:
A patient demonstrating hemodynamic instability or extreme
symptomatology should be DC cardioverted.
If hemodynamically stable:
Normal QRS in ECG: Vagal maneuvers and AV nodal blocking drugs.
Narrow QRS without AF in ECG: Adenosine,Verapamil etc.
Wide QRS in ECG :( Orthodromic AVRT/ Antidromic AVRT/ AF/Flutter):
we can use Procainamide,Flecainide, Sotalol, or Amiodarone.
14. MANAGEMENT:
β-Blockers, Calcium channel blockers, Digoxin, and Adenosine
should be avoided in patients presenting with wide complex
tachycardias as they may precipitate ventricular fibrillation.
If the tachycardia persists, synchronized DC Cardioversion is
the treatment of choice. Energies of at least 200 J are likely to be
required.
15. Percutaneous
Therapy….
• RFA is effective 85% to 98% of the
time,
• Recurrence rates are 5% to 8%.
• Catheter ablation should be
considered for high risk patients with
symptoms or tachycardias refractory to
medical therapy, intolerance to medical
therapy and those with high-risk
occupations -Pilots.
16. WPW and Sudden
Cardiac Death…
ECG pattern suggestive of WPW syndrome
have only 0.5 % chance of sudden cardiac
death.
Risk factors:
•Shortest pre-excited RR<250 ms
•Symptomatic tachycardia
•Multiple APs
•Ebstein’s anomaly
•Familial WPW