Supraventricular Tachycardia SVT,Electrophysiological/EP Study

ISSN 0973 - 0958

Arrhythmias

Pediatrics Cardiology in Children

Rheumatic Fever

Congenital Heart Disease

Cardiac Failure

Arrhythmias

Pulmonary Hypertension in Children: An Overview

Clinical Tools

Clinical Vignettes

Diseases & Conditions

Drugs Interaction Calculator

Podcasts

Patient Management Online

Diagnostic Dilemma

Question of the Day

Diagnostic Aid

VACCINE REMINDER

Get the Vaccine Schedule for your child."

Ask Queries

SPECIALIST ANSWERS

FIND DIAGNOSIS

Today's Poll

Should all patients with viral respiratory infection be treated with oseltamivir in current epidemic of H1N1 influenza_?

Yes, it may be H1N1

No, only if test is positive for influenza

Only in sick patients admitted in ICU

Vote

Results

ARRHYTHMIAS

Related topics

Conduction System and QRS Complex in Arrhythmias

Arrythmias with Normal Heart Rate and Bradycardia and Tachycardia

Dr N.C.Joshi
Consultant Pediatrician,
Consultant at Nanavati Hospital,
Ex Dean:-B.J.Wadia Children's Hospital.

SUPRAVENTRICULAR TACHYCARDIA ( SVT)

Definition : Tachycardia resulting from an abnormal mechanism dependent upon structures above the bifurcation of the bundle of His for propagation and excluding atrial flutter or fibrillation.

A. Characteristics in Children

90% narrow QRS
May be difficult to see P wave
Orientation and location of P waves suggest mechanism of tachycardia
BPM usually around 300
May be difficult to see P waves
Orientation and location of P waves will help in diagnosing type of tachycardia.

Mechanisms of Supraventricular tachycardia :

Probable Reentrant Mechanism

Orthodromic reciprocating
Antidromic reciprocating
AV nodes reentry
Permanent junctional reciprocating tachycardia( PJRT)
Sinus node reentry
Atrial muscle reentry

Presence of Bypass Tracts

Atrioventricular or accessory connections
Wolff-Parkinson-White
Unidirectional retrograde accessory pathway (URAP)
intranodal pathways
Dual AV nodal pathways

Probable Abnormal Automaticity

Atrial ectopic tachycardia(AET)
Chaotic atrial tachycardia s
Junctional ectopic tachycardia

ATRIAL FLUTTER :

Characteristics :

Typical saw-toothed P waves
Rate 280-450 BPM (Infants may have even 500BPM!)
Atypical in Post-op hearts
May be modified by drugs

ATRIAL FIBRILLATION

Characteristics :

Irregularly irregular rate
Intermittent P waves
If WPW, may have variable QRS morpholog

VENTRICULAR TACHYCARDIA

Definition : Wide QRS tachycardia originating in the ventricle

Characteristics :

Dissociation from atria proves Ventricular tachycardia
Change in morphology of QRS ( particularly if abnormal in sinus )

ELECTROPHYSIOLOGICAL (EP) STUDY

WHY IS IT REQUIRED ?

To determine if tachycardia is present
To determine the mechanism of tachycardia
For drug testing if tachycardia is present
To locate the origin of critical structures
Ablation of the origin of critical structures

TREATMENT :

Depends on mechanism
For abnormal automaticity-Decrease Phase 4 depolarization
For Reentry- Reduce the excitable gap
For Both- eliminate the source (radiofrequency ablation or surgery)

Radiofrequency Ablation :

Procedure :

Connect catheter and grounding pad to generator
Apply current at radiofrequency
Observe effects

Mechanism :

It causes a thermal burn. Tip temperature is approximately 70 degree Celsius

Applications :

It is used in the treatment of

SVT
Flutter
VT

Surgery :

Applications are the same
Procedure is maybe excision or cryosurgery

Last created on 11-01-2001
Last updated on 01-01-2006

Next : Predisposing Factors and Microbiology of Infective Endocarditis

Mail To Your Friend

Print This Article

Diseases & Conditions

Pediatric Oncall Journal

Pediatric Conferences

Ped Tools

Adverse Drug Reactions

Pediatric oncall book store

Partner Sites

Infection in Children

Pedcall

Medical ADRIS

Vaccine Reminder

Pediatric Oncall Journal

Educational Section

Nutrition

Skin Problems

Swine Flu Center

Health Solutions from our sponsors

DHA

Baby Massage

Disclaimer:

The information given by www.pediatriconcall.com is provided by medical and paramedical & Health providers voluntarily for display & is meant only for informational purpose. The site does not guarantee the accuracy or authenticity of the information. Use of any information is solely at the user's own risk. The appearance of advertisement or product information in the various section in the website does not constitute an endorsement or approval by Pediatric Oncall of the quality or value of the said product or of claims made by its manufacturer.

Sitemap For Doctor

Sitemap For Parent

Sitemap For Kids