Pediatric DysrhythmiasBoard Review

Dr. Sahar K.K. AttiaDr. Sahar K.K. Attia

Pediatric Specialist,KKHPediatric Specialist,KKH.

May ,2015

Pediatric dysrhythmias

Treatment not requiredTreatment not required Treatment Treatment isis required required

Sinus arrhythmiaSinus arrhythmia Supraventricular Supraventricular tachycardiatachycardia

Wandering atrial Wandering atrial pacemakerpacemakerIsolated premature atrial Isolated premature atrial contractionscontractionsIsolated premature Isolated premature ventricular contractionsventricular contractions

Ventricular tachycardiaVentricular tachycardia

First degree AV blockFirst degree AV block Third degree AV block Third degree AV block with symptomswith symptoms

Pediatric dysrhythmias

• Vital to be aware of arrhythmias that occur in

otherwise healthy children

• Management is individualized

• Does child have history of heart disease?

• Are symptoms present?

Sinus arrhythmia

• Most common irregularity of heart rhythm seen in children

• Normal variant

• Reflects healthy interaction between autonomic respiratory and cardiac control

activity in CNS.

• Heart rate increases during inspiration and decreases during respiration

Sinus arrhythmia

Wandering atrial pacemaker

• Atrial pacemaker shifts from sinus node to another atrial site.

• Normal variant, irregular rhythm

Isolated PAC’sIsolated PAC’s

• Premature atrial contractions• Benign in absence of underlying heart dz• Common in newborn period• Early p wave, sometimes with different

morphology than a sinus p wave• Can be either:

– Not conducted to ventricle, apparent pause– Conducted to ventricle with aberrant or

widened QRS complex ( careful not to mix up with PVC’s)

Isolated PAC’sIsolated PAC’s

Premature Ventricular ContractionsPremature Ventricular Contractions (PVC’s) (PVC’s)

• Not very commonly seen in children

• Incidence of 0.3 to 2.2 %

• Early, wide QRS complexes

• T waves in opposite direction of QRS

• Unifocal PVC’s are most encountered type.

• Bigeminy, sinus beat followed by PVC, repeating as a pattern, also frequently seen.

PVC’s

• If unifocal, disappear with exercise, and associated with structurally and functionally

normal heart, then considered benign, no therapy needed.

PVC’s evaluation

• 12 lead EKG, Echocardiogram

• Perhaps Holter monitoring

• Brief exercise in office to see if ectopy suppressed or more frequent

• Multifocal or paired PVC’s more worrisome

• Medications usually not needed

• Advise patients to avoid caffeine and other stimulants

First degree AV block

• Commonly seen (up to 6% normal neonates)

• PR interval is greater than upper limits of normal for a given age

• PR interval is age and rate dependent

• 70-170 msec in newborns is normal

• 80-220 msec in young children and adults

• Generally does not cause bradycardia since AV conduction remains intact

First degree AV blockFirst degree AV block

• Diseases that can be associated with first degree AV block:

- rheumatic fever, rubella, mumps, hypothermia, cardiomyopathy, electrolyte

disturbances

Third degree AV block

• AKA complete heart block

• Most common cause of abnormal bradycardia in infants and children.

• Complete disassociation between P waves and QRS complexes

Third degree AV block

• Can be congenital – in this case it is strongly associated with maternal SLE.

• Mom of an infant should be worked up.

• Most common structural heart defect associated is corrected transposition of

great vessels

Third degree AV block

• May be asymptomatic – follow clinically

• Slower the heart rate, and wide QRS escape rhythms place into high risk group

• May need implantable pacemaker:

-significant bradycardias, syncope, exercise intolerance, ventricular dysrhythmias, or ventricular arrhythmias, structural disease.

• Possible acute treatment: isoproterenol

Supraventricular tachycardia

• Most common abnormal tachycardia seen in pediatric practice

• Most common arrhythmia requiring treatment in pediatric population

• Most frequent age presentation: 1st 3 months of life, 2nd peaks @ 8-10 and in

adolescense• Rapid, regular, usually narrow QRS

rhythm, originating above the ventricles

SVT

Figure 5-42 Supraventricular tachycardia

- Note a normal QRS complex tachycardia at a rate of 214 beats/minute without visible P

waves.

SVT

• Paroxysmal, sudden onset & offset

• Rates of SVT vary with age

• Overall average rate for all ages: 235 bpm

– 1st 9 months of life: avg rate is 270 bpm

– Older children: avg rate is 210 bpm( 180-250)

• P waves difficult to define, but 1:1 with QRS

• Important to differentiate from sinus tach

SVTSVT

• Older kids can describe a sensation of a fast heart rate, palpitations, or

chest tightness.

• Hemodynamic compromise in newborns and those with structural

heart disease

• Those with typical symptoms would benefit from cardiac consultation

SVT - Treatment

Goal: - Identify unstable patients, differentiate from

sinus tachycardia, and terminate the rhythm

- Vagal maneuvers in stable patients.

Adenosine if IV access readily available– Stop conduction through AV node– Helps to define p waves if unsure of etiology– 0.1 mg/kg (max 6 mg), repeat 0.2 mg/kg ( max 12

mg) in line closest to central circulation– Need continuous ECG and BP monitoring

SVT - Treatment

• Synchronized cardioversion

• Amiodarone, Procainamide if above unsuccessful.

• Transesophageal atrial pacing can also be performed

SVT - Treatment

• Need post conversion EKG – identify those with WPW syndrome ( 25 % pts with SVT)

• Will also need an echo – identify structural problems

• Radiofrequency catheter ablation – Frontline treatment– Very effective– Cutoff points usually are 5 y.o. and 15 kg, unless severe

SVT

• Observation and expectant management• Medications

– Digoxin and beta blockers as first line– Flecainide, sotalol, amiodarone

Other SVT’s

• A flutter, A fib, ectopic atrial tachycardia, junctional tachycardias.

• Not commonly seen in pediatric patients

• Adenosine does not terminate these rhythms, originate above AV node

• Treatments: procainamide, amiodarone, cardioversion, or ablation

SVT - WPW

Figure 5-43 Wolff-Parkinson-White syndrome. Note the characteristic findings of a short P-R interval, slurred

upstroke of QRS (delta wave), and prolongation of the QRS

interval.

Ventricular tachycardiaVentricular tachycardia

• Sustained V-tach is uncommon, needs workup

• Regular wide complex tachycardia

• Atrioventricular dissociation

• Life threatening arryhthmia

• Often presents in those who have had open heart surgical repair, or those with

cardiomyopathies, myocarditis, or tumors

V-Tach

Treatment: IV lidocaine, procainamide, amiodarone.

- If critically ill: synchronized cardioversion

- Long term: meds, ablation, or defibrillator

Ventricular fibrillation

• Seen in children with EKG abnormalities such as long QT syndrome, or Brugada syndrome

• Cardiomyopathies, structural heart disease causing ventricular dysfunction

• Treatment: immediate defibrillation, CPR

V-fib

• Brugada syndrome – inherited arrhythmia, autosomal dominant person goes into v-fib, faints, dies suddenly.

Treatment: defibrillator, careful screening