Heart failure in childhood

HEART FAILURE IN CHILDHOOD

by Siti Sarah Nasution

1211356

CONTENTSPhysiology Definition

EpidemiologyEtiology

PathophysiologyClinical Features

InvestigationsManagement

Differential Diagnosis

CARDIAC PHYSIOLOGY

CARDIAC PHYSIOLOGY

DEFINITIONHeart Failure occurs when the heart is unable to deliver adequate cardiac output to meet the metabolic needs of the body.

Nelson Textbook of Pediatrics, 19th Edition.

EPIDEMIOLOGY

CongenitalVSD

ASD

Aortic Stenosis

PDA

Coarctation of the Aorta

Cardiac Muscle RelatedRheumatic Heart DiseaseEndocarditisMyocarditis

OthersArrythmiaThyrotoxicosisAnemia Toxic drugs

Most common case of Heart Failure in Malaysia:(from Malaysian Pediatrics Association)

ETIOLOGY BY AGE GROUP

PATHOPHYSIOLOGY

FACTORS AFFECTING CARDIAC PERFORMANCE:

Preload AfterloadContractility Heart Rate

AFTERLOAD VS PREALOAD PATHOLOGY

AfterloadObstruction

High Lt ventricle systolic pressure

Increase contractility sue to pressure overload.

Prolongation cause diminish cardiac contractility

HF

Preload

LtRt ventricle

Rt ventricle P. artery

Lungs Lt atrium

Lt atrium Lt ventricle

• Lt ventricle : High load

Compensation.Remodelling eg dilatation,

hypertrophy

• Lt atrium high pressure : Increase pulmonary venous pressure

Pulmonary edema

ABNORMAL LOADING CONDITIONS

Preload (Volume overload)

VSD PDA Valvular Insufficiency

*Most common cause in children.

Afterload(Pressure overload)

• Aortic Stenosis• Pulmonary

Stenosis• Coarctation of

the Aorta

Contractility :

Normal : Frank-Starling Law – is the ability of the heart to

change force of contraction dependent on the change of preload.

HF: Myocardium abnormalities either congenital or acquired.

(Intrinsic contractility compromised). Eg: myocarditis,

cardiomyopathy, muscular dystrophy.

Heart Rate :

Eg: Tachyarrythmias shortens the diastolic time interval for

ventricular filling. Also affect the time for coronary perfusion.

LEFT, RIGHT AND BIVENTRICULAR HEART FAILURE

1. Left-sided heart failure.

Reduce left ventricular output. High pressure in left atrial, pulmonary vein. Pulmonary congestion.

2. Right-sided heart failure.

Reduce right ventricular output, for any given right atrium pressure. Eg. Chronic lung disease.

3. Biventricular heart failure.

Secondary to the progression of the disease. Eg. Dilated cardiomyopathy, ischemic heart disease.

Heart fails to keep pace with the hemodynamic demands.

Decrease myocardial performance. Myocardium metabolic demand unmet.

Compensatory mechanism take place.

Initially compensated, at the end become decompensated.

Functional and structural disturbance of the heart

COMPENSATORY MECHANISM

1. Frank-Starling Mechanism

2. Neurohormonal System Activation - RAAS - Symphatoadrenal Axis

3. Myocardium Structural Changes - Hypertrophy, apoptosis etc.

CLINICAL FEATURES

tachypnea orthopnea wheezingpulmonary edema

hepatomegaly edema distendedneck veins

Sign and Symptoms in Infancy

Symptoms Feeding difficulty : poor suck, prolonged time to feed,

sweating during feeding Recurrent chest infections Failure to thrive

Sign Resting tachypnoea, subcostal recession Tachycardia, poor peripheral pulses, poor peripheral perfusion Hyperactive praecordium, praecordial bulge Hepatomegaly Wheezing

In children, the sign and symptoms may be similar with adults.

• Fatigue• Effort intolerance• Anorexia• Abdominal pain• Dyspnea• Orthopnea• Cough• Edema (dependent part of body)• Cardiomegaly• JVP raised

Common sign of heart failure in adults eg.

Increase jugular venous pressure, Leg edema, Basal crackles

Are NOT usually found in chlidren.

INVESTIGATION

Chest X-ray -cardiomegaly-pulmonary edema

ECG-chamber hypertrophy-assess the cause of HF (Not diagnosis)-evaluate rhythm disorder- QRS morphologic n ST-T wave abnormalities

= myocardial inflammatory ds n pericardiatis

Echocardiography-assess ventricular function-parameter : Children – fractional shortening Adult – ejection fraction

Doppler Ultrasound-estimate CO-Assess cardiac function, wall motion abnormalities

MRA (Magnetic Resonance Angiography)

-Lt Rt ventricle: function, volume, mass.

Serum B-type Natriuretic Peptide (BNP)

-cardiac neurohormone released in response to increased ventricular wall tension

-Increase in: Adult : CHF Children : HF (systolic dysfunction) & volume

overload (Lt-Rt shunt)

Arterial Blood gases

-pH, PaO2, PaCO2 abnormalities checking.

Right sided Heart FailureCardiomegaly

TREATMENT

AimEnhancing cardiac contractilityReducing the preload & afterloadImproving oxygen delivery

General

O2 supplement, in a propped up position Strict bed rest rarely necessary Keep warm n gentle handling Fluid restriction (3/4 normal) only if not dehydrated or in

shock Correct the anemia, electrolyte imbalance, treat concomitant

chest infection

ANTI-FAILURE MEDICATION

Frusemide •loop diuretic, •use with potassium supplement or together with potassium sparing diuretics

Spironolactone •potassium sparing diuretic•modest diuretic effect

Captopril •ACE inhibitor•Afterload reducing agent

Digoxin Useful in:excessive tachycardia supraventricular tachyarrhythmias

IV Inotropic agents•Use for high force contraction• Acute HF•Cardiogenic shock•Post low output syndrome

SPECIFIC MANAGEMENT

Etiology establishment Specific treatment for targeted etiology Congenital - Surgical or transcatheter

treatment Heart block - Pacemaker Post infectious glomerulonephritis - Control

BP Acute rheumatic carditis - High dose aspirin

DIFFERENTIAL DIAGNOSIS Acute Renal Failure Acute Respiratory Distress Syndrome Cirrhosis Emphysema Nephrotic Syndrome Pneumonia Pulmonary Edema

REFERENCES

Nelson Textbook of Paediatrics, 19th edition. Nelson Essentials of Paediatrics, 7th edition. Paediatric Protocols for Malaysian Hospitals,

3rd edition. Davidson’s Principles and Practice of

Medicine, 21st edition.