WPW syndrome characterized by all except
WPW syndrome also Wolff-Parkinson-white syndrome is characterized
1. Short PR INterval < 120 ms
2. Prolonged QRS complex > 110ms
3. ST-segment T wave discordant changes (major QRS complex is opposite to ST and T wave)
4. Psuedo infarction pattern (in 70% of patients)
Electrical impulse originating from atria can only reach ventricle through the AV node. The rest of the tissue in between does not allow conduction of impulse (fibrous band). This is a kind of protection for ventricles.
In patients with WPW syndrome apart from AV node bypass tract connecting atria to ventricles are present. These abnormal bypass tract are responsible for supraventricular arrhythmias.
Unlike in other patients, atrial fibrillation in these cases can be very dangerous. This is because inpatients without bypass tract (normal) AV node is the only route for conducting impulse originating from atria. AV node has longer refractory period so it filters impulses coming thus ventricles are protected. but in patients with WPW syndrome with antegrade bypass tract conduction AV node filter is absent thus it can be very dangerous.
Treatment of WPW syndrome
Catheter ablation of the bypass tract is needed to prevent supraventricular arrhythmia.
if the patient develope supraventricular tachycardia and the patient is hemodynamically stable amiodarone, procainamide or ibutilide may be used. but may require DC cardioversion more so the patient is hemodynamically unstable