Treatment of WPW Syndrome with which of the following drug/therapy should be better AVOIDED?
Ans. a (Digitalis) (Ref KDT 6th/499; H-17th/1435)PRECAUTIONS AND CONTRAINDICATIONS FOR DIGITALIS USE# Acute myocarditis (diphtheria, acute rheumatic carditis, toxic carditis)# Renal or severe hepatic disease# Hypokalemia# Thyroxoicosis# Myxoedema# Myocardial infarction# WPW syndrome (digitalis decreases ERP of bypass tract in 1/3rd of patients. VFV may occur. It can increase the chances of reentry by slowing conduction in normal AV bundle and accelerating in aberrant bundle).# AV block (Partial)# Ventricular tachycardia# Elderly******(Mnemonic = A RHTDM WAVE)*****Cardiac manifestationsExtracardiac manifestationsDisturbance in cardiac rhythm# Ventricular premature beats# Bigeminy# Ventricular tachycardia# Ventricular fibrillation# A V Block of varying degree of severity may occur.# Anorexia, nausea and vomiting (earliest sign)# Weight loss# Cachexia# Neuralgias# Gynecomastia# Yellow vision# DeliriumNon-paroxysmal atrial tachycardia with variable A V Block is characteristic of Digitalis intoxicationWPW syndrome# ST-segment elevation in leads V1 and V2 is consistent with the Brugada syndrome, QT interval changes are consistent with long or short QT syndromes, while short PR interval and delta wave consistent with Wolff-Parkinson-White (WPW) syndrome.# The diagnostic triad of WPW consists of:- A wide QRS complex- Relatively short PR interval and- Slurring of the initial part of the QRS (delta wave), the latter effect due to aberrant activation of ventricular myocardium.# The presence of a bypass tract predisposes to reentrant supraventricular tachyarrhythmias (also AF).# Cryomapping can be used to confirm the location of a desired ablation target, such as an accessory pathway in WPW synd, or can be used to determine safety of ablation around AV node by monitoring AV conduction during cooling.# Ablation of bypass tract offers a permanent cure of supraventricular tachycardia. The advent of radio-frequency ablation (RFA) has virtually eliminated the need for open surgery.Additional Educational PointsECG Clues Supporting the Diagnosis of Ventricular Tachycardia# AV dissociation (atrial capture, fusion beats)# QRS duration > 140 ms for RBBB type V1 morphology; V1 > 160 ms for LBBB# type V1 morphology# Frontal plane axis -90deg to 180deg# Delayed activation during initial phase of the QRS complex# LBBB pattern--R wave in V1, V2 >40 ms# RBBB pattern--onset of R wave to nadir of S > 100 ms# Bizarre QRS pattern that does not mimic typical RBBB or LBBB QRS complex# Concordance of QRS complex in all precordial leads# RS or dominant S in V6 for RBBB VT# Q wave in V6 with LBBB QRS pattern# Monophasic R or biphasic qR or R/S in V1 with RBBB pattern
Digitalis
DC cardioversion
Adenosine
Procainamide
C.V.S.