Arrh thmias in Ad lts WithArrh thmias in Ad lts WithArrhythmias in Adults With Arrhythmias in Adults With Congenital Heart DiseaseCongenital Heart DiseaseCongenital Heart DiseaseCongenital Heart Disease

An OverviewAn OverviewAmjad Kouatli. MD, FAAP

Consultant Pediatric CardiologistKFSH&RC Health Care SystemKFSH&RC Health Care System

Jeddah.

Introduction

• In the USA there are approximately illi d lt ith CHDone million adults with CHD

• There are 200,000 new paediatric ti t ith CHD hipatients with CHD reaching

adolescence every year

Adults with CHD have Increased incidence of arrh thmia compared to normal hearts

H t ith CHDN l h t

of arrhythmia compared to normal hearts

Hearts with CHDNormal hearts

Incidence of V. Arrhythmia in Normal Hearts, d H t With CHD l h 1988and Hearts With CHD, walsh 1988

Arrhythmia Distribution by Disease Groupy y p(Pediatric Radiofrequency Ablation Registry 1991-1994) G 2061

Group # APSVT AET AFL PJRT AVNRT JT VT MAGroup # APSVT AET AFL PJRT AVNRT JT VT MA

Myop 68 12 32 2 15 15 1 3 1

Ebstein 43 40 2 2 3

Must, Senn 21 4 16 2

Fontan 46 10 3 25 5 1

l-TGA VSD, PS

10 9 2

d-TGA A C O

4 3 1 cAVC, DORV TOF 17 9 4 3 3

S l D f 22 12 3 1 4 1 1Septal Defects 22 12 3 1 4 1 1

Risk Factors for Arrhythmia yin Adults With CHD

(1) Congenital abnormalities of conduction ( ) gsystem.

(2) Abnormal Hemodynamics

(3) Cardiac surgery

(1) Congenital abnormalities of(1) Congenital abnormalities ofconduction systemconduction system

Abnormal sinus node locationAbnormal sinus node locationAbnormal sinus node functionAbnormal AV node and AV cond ctionAbnormal AV node and AV conductionAbnormal atrio-ventricular accessory pathway

Abnormal sinus node locationb o a s us ode ocat o

Abnormal sinus node function (SND)( )• SND or sick sinus syndrome is

f tl t ifrequently encounter in

– Secundum ASD Kugler 1991, Clark EB 1982

– Sinus venosus ASD Clark et al 1975, Arensman et al 1986

– AV canal Fournier et al 1986

Sinus arrest in an AV canal Patient

Abnormal AV node and AV conductionAbnormal AV node and AV conduction

• Abnormal embryonic development of AV nodeAbnormal embryonic development of AV node from AV canal musculature

Ab l d l t f t l fib ti• Abnormal development of central fibrous tissue

• Lack of union between AV node and AV bundle assuming separate development

• Formation of conduction system from anterior endocardial tissue (l TGA)endocardial tissue (l-TGA)

Lev M. 1972

• Can cause minor ECG changes or CHBg

AV canal

AV node and bundle are posterior at the AV valve / ventricular septal junction.ventricular septal junction.

The AV node is posterior to CS (QRS - 60 to -135)

Moss and Adams Sixth edition

AV d i th t i l

Corrected TGAAV node is near the atrial septum along the anterior aspect of AV ring. p gThe bundle is related to the pulmonary outflow p ytract anterior to the VSD rim if presentIncrease risk of CHB

Accessory pathwaysAccessory pathways

• Wide spectrum of CHD are associated with WPWWide spectrum of CHD are associated with WPW

9 % of Ebsteins9 % of Ebsteins 2 % of l-TGA1 % of hypertrophic cardiomyopathy1 % of hypertrophic cardiomyopathy

Milstein et al 1986

• AP are frequently left sided, pts with CHD have a stronger association with the tricuspid valvestronger association with the tricuspid valve whether right or left-sided

Cardiac Arr in Children and young adult p 197

(2) Abnormal Hemodynamics( ) y• Causes chamber dilatation or hypertrophy

• Complex CHD has more hemodynamic problemsproblems

• Atrial dilatation can causeAtrial dilatation can cause– SA or AV node dysfunction or atrial tachycardia

• Ventricular dilatation or hypertrophy – Bundle branch block or ventricular arrhythmia

• Arrhythmia is less tolerated in patients with id l h d i blresidual hemodynamic problems

Arrhythmias increase with age due tol d b l h d iprolonged abnormal hemodynamics

SNRT i t dSNRT in unoperatedASD2. 34 pt

normal in < 3 yo,Prolonged in 70% > 5 yog yRuschhaupt et al Am J Cardiol 1984

Atrial arrhythmia inAtrial arrhythmia in unoperated ASD sv• 14% mean age 14 yo• 14%, mean age 14 yo.

Kyger 1978

• 55%, mean age 55 yo. St John et al 1981 3 yo22 yo

(3) Cardiac Surgery( ) g y

• Three major substrates for developing• Three major substrates for developing arrhythmia after heart surgery; scarring, hypertrophy, and dilatationyp p y,

• All are present to some degree in postAll are present to some degree in post operative patients with congenital heart disease

• Arrhythmia differ according to types ofArrhythmia differ according to types of heart disease and surgical technique.

Incidence of arrhythmia varies according to i l t h i i TOFsurgical technique in TOF

0 % t i l fl tt 4 %Transatrial Transventricular

0 % atrial flutter 4 %3 % v. arrhythmia 40 %1 late death 41 late death 4

Dietel et al . 1994

Incidence of arrhythmia varies in the samet f h t d f ttype of heart defect

Secundum ASD Sinus venosus ASDSecundum ASD Sinus venosus ASD

14% atrial arrhythmia 33%14% atrial arrhythmia 33%Young et al . 1973

Incidence of arrhythmia varies in differentt f h t d f ttypes of heart defect

Surgery near SA node Surgery near AV node

ASD, Fontan, Mustard

Consequences:

AVSD, VSD

Consequences:Consequences:SND, atrial flutter

Consequences:AV block, can be late

Atrial Flutter

S ft l t i l• Seen after complex atrial surgery

• Most common tachyarrhythmiaMost common tachyarrhythmia after Mustard, Senning, and Fontan

• Related to sinus node damage and extensive atrial suture lines

• Macro re-entrant rhythm confined to the atria The circuit coursesto the atria. The circuit courses around the atriotomy scar

Ventricular Tachycardia

• Produced after: - ventriculotomy ( TOF repair)ventriculotomy ( TOF repair)

- surgery in dilated ventricles ((TOF repair without ventriculotomy)

M t f dd d th• Most causes of sudden death in post-operative patients are thought to be due to VTthought to be due to VT

Sudden DeathSudden Death

• Annual risk of SD in paediatrics is 0.001 %Neuspiel 1985 Driscol 1985Neuspiel 1985, Driscol 1985

• Annual risk in palliated heart disease is 3%pSilka 1998, Gillett 1997

C t id f VT f• Current evidence favors VT as precursor of sudden death

• Hence prevention / treatment of VT is the best way to prevent sudden deathway to prevent sudden death.

Incidence of sudden death from t i l h th iventricular arrhythmia

DORV 18% Shenet al 1990 • Highest incidence of SD in preoperative CHD

l –TGA

DORV 18 % Shen et al 1990 l –TGA

EisenmengerMustard 3-15 % Hayes et al 1986Vetter et al 1988

• Highest in post-operative CHD

DORV

TOF 0-5 % Garson et al 1979

Chandar et al 1990 DORVMustard operationEbstein's

VSD 0-4 % Fournier et al 1986

Moller et al 1985 Aortic stenosis

Fontan 2-3 % Webber et al 1989 Driscoll et al 1992Driscoll et al 1992

Kanter RJ & Garson A. 19??

Sudden Death

• No way of predicting patients at risk of• No way of predicting patients at risk of VT/sudden death

• Risk factors:- PVC with RVOTOPVC with RVOTO- RV volume overload and enlargement

secondary to chronic PI - Delayed surgery, RV pressure overload and

myocardial hypoxemia are arrhythmogenicDeanfield et al 1984Deanfield et al 1984

- Others : Residual VSD, transatrial versus transventricular repair, and longer follow upp , g p

ConclusionCo c us o• Arrhythmias are important cause of morbidity in

d l i h CHDyoung adults with CHD

• Current knowledge on arrhythmias and suddenCurrent knowledge on arrhythmias and sudden cardiac death after repair of CHD is inadequate

• Important to detect arrhythmias especially in high risk patients such as DORV, Rastelli, Mustard, Senning Fontan and aortic or mitral valveSenning, Fontan, and aortic or mitral valve replacement

• Prophylactic measures to prevent sudden death are still controversial ( e.g. digoxin for life in Mustard

i )patients)