Essential of paediatric cardiology

Robyn SmithDepartment of Physiotherapy

UFS2011

Causes of CHD

Genetic

Maternal Environmental

First 8-10 weeks of gestation critical in development of the

heart

CHD affects 1% of children

Foetal circulation

• Not dependant on the lungs for respiration

• Placenta is used for gaseous exchange

• All of the blood flowing through the chambers of the heart, arteries and veins is rich in Oxygen

• Pulmonary vessels are vasoconstricted

Change in circulation after birth• As the baby takes its first breath the

lungs expand, causing the lung P to fall and air enter lungs.

• Once the lungs are filled with air and the oxygen level in the child’s blood rises resulting muscle wall of the ductus arteriosus contracts no longer allowing blood to flow through it (10-15 hours after birth)

• This forces pulmonary circulation into action

• Now child has separate oxygenated and de-oxygenated blood and relies fully on the lungs for gaseous exchange

Classification of CHD

CHD

Cyanotic lesions

↓O2 saturation in the blood

Acyanotic lesions

O2 saturation unaltered, pressure or volume related

issued

Acyanotic lesions

Left to right shunting of blood

PDA

ASD

VSD

AVSD

Obstructive

Coarctation

Pulmonary stenosis

Aortoc stenosis

Conditions where there is a left to right shunting of blood

Patend Ductus Arteriousus (PDA)

Patend Ductus Arteriousus (PDA)

• Ductus arteriousus open in the foetal circulation

• Vascular connection between the main pulmonary trunk and the aorta

• Closes soon after birth • If it stays open excessive blood shunts from

the aorta ton the lungs• Resulting in pulmonary oedema• Common in premature infants

Patend Ductus Arteriousus (PDA)

Clinical signs and symptoms of a PDA:

Poor feedingFailure to thrive (below weight for and height for age) Sweating with crying or play Persistent tachypnoea or breathlessness (dyspnoea)Easy tiring Tachycardia Frequent lung infections A bluish or dusky skin toneDevelopmental delay

Medical management PDA

• Management Closing of PDA:

• Medication (indomethacin) induces closure• Surgical closing via a thoracotomy

Atrial Septal Defect (ASD)

Atrial Septal Defect (ASD)

• Opening or whole in the wall separating the atria• Free communication of blood between the two

atria. • Seen in 10% of all congenital heart disease• Rarely presents with signs of congestive heart

failure or other cardiovascular symptoms• The right atrium and ventricle may enlarge over

time• Cyanosis does not occur unless pulmonary

hypertension is present.

Clinical signs and symptoms of ASD

• Most are asymptomatic • May have easy fatigability or mild growth

failure.

Atrial Septal Defect (ASD)

Medical management of ASD

• Surgery of catheterization

Venticular Septal Defect (VSD)

Venticular Septal Defect (VSD)

• Abnormal opening in the ventricular septum.• Allows free communication between the right and left

ventricles • Oxygen rich blood in the left ventricle pumped into the

right ventricle instead of to the body. • In a large VSD excessive blood is pumped to the lungs

resulting in congestion and shortness of breath.• In return excessive amounts of blood are pumped back

from the lungs to the left heart overburdening and enlarging it resulting in CHF

Venticular Septal Defect (VSD)

Clinical signs and symptoms of VSD

• Small VSD most children are asymptomatic • In the case of moderate to large VSD the child

will be symptomatic. dyspnoeafeeding difficultiesfailure to thrive recurrent respiratory infections profuse sweating

Medical management of VSD

• In case of a small VSD 50% will close spontaneously by age 2yrs

• Large VSD’s are usually closed surgically

Atrioventricular Septal Defect (AVSD)

Atrioventricular Septal Defect (AVSD)

• Result from incomplete fusion of :tendocardial cushions which help to form the lower

portion of the atrial septum, the membranous portion of the ventricular septum

and the septal leaflets of the triscupid and mitral valves.

• 4% of all CHD• Commonly associated with chromosomal

disorders such as Down Syndrome

Atrioventricular Septal Defect (AVSD)

Clinical signs and symptoms of an AVSD

• The child may present with:CHF in infancyrecurrent respiratory infectionsfailure to thriveexercise intoleranceeasy fatigability

Medical management of AVSD

• Surgery is always required.

Prior to surgery congestive symptoms are treated.Pulmonary banding maybe required in premature

infants or infants < 5 kg.Correction is done during infancy to avoid

irreversible pulmonary vascular disease.

What is pulmonary banding?

• Primary aim procedure is to reduce excessive pulmonary blood flow

• In order to protect the pulmonary vasculature from hypertrophy and

• irreversible (fixed) pulmonary hypertension.

Other less common conditions

Surgical complications: Pulmonary hypertension

• Can be a severe complication post operatively• Children at risk of are those with excessive

shunting of blood from left to right e.g. VSD, AVSD• This results in excessive blood flow to the lungs

resulting in distension and damage to the pulmonary artery wall which becomes muscularised

• Pulmonary artery is then unable to dilate and vulnerable to reactive vasoconstriction

May predispose the child to a hypertensive crisis.

The following may predispose a child to a hypertensive crisis:

• Hypoxaemia• Hypercapnea• Metabolic acidosis as well as • relentless handling (including by the physiotherapist) • Tracheal suctioning may predispose the child to a

hypertensive crisis.

Surgical complications: Pulmonary hypertension

• In the case of a pulmonary hypertensive crisis the pulmonary arteries constrict resulting in an increase in pulmonary artery pressure and CVP.

• The systemic blood pressure drops suddenly resulting in cardiac arrest.

• Treatment includes sedation, paralysis and the administration of Nitric Oxide and 100% oxygen to try and facilitate pulmonary vasodilatation

Pulmonary hypertension and

PT

Only do PT if clearly indicated

Adequate sedation

Muscle relaxant /paralysisO2 supplementation

BE QUICK and effective !!!!

Monitor vitals

Conditions where there is a obstructive cause

Coarctation of the aorta

Coarctation of Aorta

• Congenital narrowing of the aorta as it leaves the heart.

• Resulting in:increased pressures in the arteries nearest the heart,

head and arms decreased circulation in lower extremities.

• 7 % of all CHD• Male: Female ratio 3:1

Coarctation of Aorta

• This is often not evident in the newborn until the ductus arterious closes

• The blood in the left ventricle has then to be pumped out against the constriction.

• Resulting in :left ventricular hypertrophy left ventricular failure with

congestive heart failure (CHF)

Clinical signs and symptoms of coarctation

• The child may present with:CHF“Hard” breathing”WheezingExcessive sweating

Coarctation of Aorta

Medical management of a Corarctation of Aorta

• With severe coarctation maintaining the ductus with prostaglandin E is essential

• Early surgical repair and resection of the stenosis is imperative

• Simple coarctation repair have a extremely low mortality but in complex cases mortality might be higher

• A rare complication of surgical repair is paraplegia (longer cross clamping times during surgery)

• In 18% of children undergoing surgery re-coarctation occurs requiring further surgical intervention

Obstructive causes

• Asymptomatic in mild cases, • More severe cases fatigue,

syncope and dyspnoea

• Treatment is surgical repair

• Symptoms include dyspnoea, exercise intolerance, fatigue, CHF and hypoxaemia

• Treatment is surgical repair

Aortic Stenosis Pulmonary Stenosis

Obstructive causes

Aortic Stenosis Pulmonary Stenosis

Cyanotic heart lesions

Cyanotic lesions

Tetrallogy of Fallot

Hypoplastic left heart

Transposition of great vessels

Tetrallogy of Fallot (TOF)

Tetrallogy of Fallot (TOF) • Most common cyanotic heart lesion

• Has 4 components:– A high VSD– Pulmonary stenosis– Anomalous position aorta– RV hypertrophy

• Results in a right to left shunting of blood with low oxygen levels in the arteries and in the body tissues

• Resulting in cyanosis, easy fatigability, fainting and shock.• Clubbing may be observed

Tetrallogy of Fallot (TOF)

Medical management of TOF

• Early surgical intervention (TOF repair) is usually required

• Palliative care by means of anestomosis and pulmonary valvotomy can be done

Hypoplastic Left Heart Syndrome

Hypoplastic Left Heart Syndrome (HLHS)

• Most serious congenital heart malformation• Poorest of prognosis• Means :

left ventricle is extremely small and under-developed mitral valve and aortic valves may be missing

• Symptoms usually minimal until the ductus arteriosus closes causing shock and multi-organ failure

Hypoplastic Left Heart Syndrome (HLHS)

Medical management of Hypoplastic Left Heart Syndrome

• Treatment prpstaglandin E1 until surgery • Initial palliative surgeries• Heart transplant is often the suggested option

Transposition of the great vessels

Transposition of the great vessels

• big vessels are in the wrong place –aorta and pulmonary artery are switched:

Aorta arises from the RV Pulmonary arteries arise from the LV

• The 2 circulations namely the systemic and pulmonary are in parallel instead of in series

• Venous blood circulates around the body and oxygenated blood around the lungs

• May be dyspnoea, cyanosis and syncope

Medical management of Transposition of the great vessels

• Palliative surgeries including pulmonary banding or atrial septum excision

• Corrective surgery

Non-congenital heart diseases

Cardiomyopathy

• Primary heart muscle disease• chronic and (sometimes progressive disease) in

which the heart muscle is abnormally enlarged, thickened and/or stiffened.

• The condition typically begins in the walls of the ventricles and in more severe cases also affects the walls of atria

• The actual muscle cells as well as the surrounding tissues of the heart become damaged.

Clincal signs and symptoms of cardiomyopathy

• Hallmark is depressed cardiac functioning.• Eventually, the weakened heart loses the

ability to pump blood effectively leading to: heart failure or irregular heartbeats (arrhythmias or dysrhythmia)

Cardiomyopathy

"primary cardiomyopathy“

where the heart is predominately

affected cause may be due

to infectious agents or genetic

disorders

"secondary cardiomyopathy" where the heart is

affected due to complications from another

disease affecting the body

e.g. HIV, cancer, muscular

dystrophy or cystic fibrosis

Cardiomyopathy

• Cardiomyopathy can affect a child at any stage of their life.

• It is not gender, geographic, race or age specific.

• Rare disease in infants and young children.• Cardiomyopathy continues to be the leading

reason for heart transplants in children.

Complications related to CardiomyopathyArrhythmias'

CHF

Blood clots

Endocarditis

Sudden death

Heart transplantation

LAST OPTION/RESORT in end stage heart failure in children

with heart defects or cardiomyopathy that are

unresponsive to surgery or medication

Heart transplant

• Heart failure may occur in children with CHD post-operatively due to the nature of their artificial circulations

• Individual units have their own transplant protocols• A heart transplant presents a high risk of organ

rejection and systemic infection• The transplant half life of children is estimated at 18

years