Heart failure in children

Question 1

HF occurs when

Answer 1

the heart can no
longer meet the metabolic demands
of the body in case of normal venous
filling pressure.

Question 2

Cardiac output (CO)

Answer 2

= stroke volume (SV) X heart rate (HR)

Question 3

Compensatory mechanisms are:

Answer 3

◼ Increasing HR with neurohormonal controll
◼ Dilation of cardiac cavities
◼ Myocardial hypertrophy walls

Question 4

Low cardiac output

Answer 4

Congestive HF

Question 5

High output cardiac failure:

Answer 5

◼ Severe anemia,
◼ Sepsis with Gram -negative germs,
◼ Beriberi ( deficit vitamin B1) ,
◼ Thyrotoxicosis,
◼ Fistulas/arteriovenous malformations

Question 6

Low output failure
Causes

Answer 6

Normal -> 5 l/min
Failure -> 3 l/min

1.Hypertensive
2.Ischaemic heart disease
3.Valvular heart disease
4.Myocarditis

Question 7

High ouput failure

Answer 7

Pre-existing high output to meet body requirements -> 9 l/min
Failure -> 7 l/min , output still greater than normal
Diseases associated with increased blood volume :
1.Chronic Anaemia
2.Arteriovenous shunting or increased vascularity of tissues e.g. PAGET’S DISEASE OF BONE, HYPERTHYROIDISM following TRANSFUSION OVERLOAD

Question 8

Pathophysiology

Answer 8

 Myocytes exhaustion – necrosis
 Stimulation of fibroblast proliferation
 Cardiac dilatation and systolic
dysfunction

 In the acute form:
◼ adrenergic systems and renin-angiotensin-
aldosteron system activation to maintain flow.
◼ Increasing of the myocardial contractility
with peripheral vasoconstriction, fluid retention to maintain BP

Question 9

Classification

Answer 9

 Right/left
 Systolic/diastolic
 HF with low CO and increased
pulmonary vascular resistance (PVR)
or increased CO and low PVR.
 Functional - NYHA

Question 10

NYHA functional classification

Answer 10

 Class I: no limitation of activity ;
without symptoms to normal activities .

 Class II: slight limitation of activity ;
rest without symptoms .

 Class III : marked limitation of any activity ; rest without symptoms

 Class IV: any physical activity is accompanied by discomfort and symptoms are present at rest

Question 11

Ross classification

Answer 11

Score
Infant
I Asymptomatic
II Mild sweating, tachypnea at nutrition
III Tachypnea and marked sweating at nutrition
The prolongation of the nutrition time
Growth failure
IV Symptoms at rest

Children
I Asymptomatic
II Mild dyspnea on exertion
III Dyspnea on exertion
IV Dyspnea at rest

Question 12

Etiology
Infant and small children
CHD with left -right shunt - the most common

Answer 12

◼ VSD, AVSD , PDA , CTA , aorto-pulmonary window,
◼ Single ventricle without pulmonary flow obstruction,
◼ PA (pulmonary atresia) with VSD and large MAPCAs (major aorto -
pulmonary collateral arteries)
◼ TAPVR (total abnormal pulmonary venous return) without obstruction.
 Pulmonary flow increases with decreasing lung resistance

Question 13

Etiology
Infant and small children
ALCAPA

Answer 13

( abnormal left coronary artery from
pulmonary artery) - with worsening coronary
perfusion , myocardial ischemia and dysfunction.

Question 14

Etiology
Infant and small children
Cardiomyopathies

Answer 14

• idiopathic endomyocardial fibroelastosis,
• mitochondrial disease,
• storage disease ,
• carnitine deficiency ,
• hypertrophic cardiomiopathy, myocarditis.

Question 15

Etiology
Infant and small children
Noncardiac causes:

Answer 15

kidney failure, sepsis, severe
anemia, residual lesions after cardiac surgery - ventricular
dysfunction, great shunts significant valvular regurgitation,
arrhythmias.

Question 15

Etiology
elder children
LHI , RHI

Answer 15

Non-operated CHD
 Left heart insufficiency (LHI):
◼ AV valve insufficiency - AVSD, congenitally corrected TGA,
◼ aortic insufficiency – VSD with Ao prolapse, infectious endocarditis.

 Right heart insufficiency (RHI):
◼ Ebstein disease, associated or not with cardiac arrhythmias,
◼ Eisenmenger syndrome,
◼ Tricuspid or pulmonary regurgitation

Question 16

Clinical evaluation

Answer 16

 Tachycardia - the first clinical sign/exception bradyarrhythmias or AVB
 Signs of congestive vascular
 LHI - signs of pulmonary congestion and
RHI - signs of systemic congestion.
 In the final stage clinical - low CO signs
 In general, HF associated with normal CO is called compensated and HF with low CO- decompensated.

Question 17

Tachycardia – the first sign
Right

Answer 17

Right
 hepatomegaly
 Ascites
 pleural effusion
 edema
 jugular distension

Question 18

Tachycardia – the first sign
Left

Answer 18

 tachypnea
 intercostal retractions
 Beating the nasal wings
 pulmonary crackles
 Pulmonary edema

Question 19

Tachycardia – the first sign
Low CO

Answer 19

Tiredness/fatigue
Pallor
Sweating
Cold extremities
Poor growth
Dizziness / altered consciousness
Syncope

Question 20

In children the onset is rapid, with signs of
biventricular CHF.

Answer 20

◼ dyspnea with tachypnea
◼ tachycardia
◼ cough and wheezing
◼ irritability
◼ malnutrition,
◼ excessive sweating
◼ anorexia
◼ peripheral edema
◼ abdominal pains
◼ cold extremities

Question 21

Investigations

Answer 21

 Oxygen saturation,
 blood count,
 ionogram,
 Urea/creatinine - kidney function
 hepatic function
 thyroid function
 Inflammatory acute phase reaction
 BNP - natriuretic peptide - grown specifically
for HF

Question 22

Cardiomegaly

Answer 22

 Compensated HF
– cardiomegaly

 LHI
–vascular redistribution:
Kerley lines,
interstitial edem

Question 23

Echocardiography

Answer 23

 Ejection Fraction (N: 50 – 70%, in HF - < 40%)
 Shortening Fraction
 Etiology HF - CHD/valvulopaty/pericarditis

Question 24

ECG

Answer 24

 Arrhythmias  Coronary ischemic disease/myocardial infarction  Left/right ventricular hypertrophy  Conduction disturbances

Question 25

Treatment

Answer 25

 It varies with age and type of disease. 1. Treatment pathogenic ◼ Emergency - Drug Therapy ◼ It is based on understanding the etiology 2. Etiological treatment ◼ Therapy/specific procedures for cardiac arrhythmias. ◼ Cardiac surgery/transplantation - in CHD.

Question 26

Treatment patogenic-obiective

Answer 26

↑ contractility ↓ preload ↓ afterload Improvement of oxygenation and nutrition (hemoglobin)

Question 27

↑ contractility

Answer 27

inotropics: - dopamin, - dobutamin, - amrinone, - milrinone, - digoxin Digoxin can be extremely useful in HF

Question 28

↓ afterload

Answer 28

ACEI po Vasodilatators, IV: hydralazine, nitroprusside or alprostadil

Question 29

↓ preload

Answer 29

Diuretics PO / IV (furosemide, thiazide). Venous dilators (nitroglycerin)

Question 30

Specific forms HF in the newborn and infant SOS

Answer 30

 Sepsis or duct-dependent CHD  Initial management ◼ ABC, IV access; ◼ Empirical antibiotic therapy ◼ Low CO - IV dopamine 5-10 mcg/kg/min, ◼ Correction of acidosis by administering fluids and/or bicarbonate ◼ Echocardiography - need for PGE1  If echocardiography can not be performed immediately, a CHD duct-dependent must be considered - coarctation of the aorta, interrupted aortic arch, total pulmonary venous return anomaly, hypoplastic left heart syndrome, truncus arteriosus, pulmonary atresia, transposition of the great vessels.

Question 31

Specific forms HF in the newborn and infant Treatment

Answer 31

 IV alprostadil (PGE 1) is recommended for duct-dependent CHD or when they can not be excluded.  PGE1 can worsen the condition of children with TAPVR or obstructive CHD or sepsis.  Pharmacological therapy or cardioversion – in conduction and rhythm disturbances associated with HF.

Question 32

HF in elderly children

Answer 32

 Hospitalisation in PICU  Diuretics IV - furosemide  Inotropic - dopamine 5-10 mcg/kg/min to stabilize  Central venous line for venous pressure and CO monitoring.

Question 33

Chronic HF In mild forms of HF

Answer 33

◼ digoxin (0.008-0.010 mg/kg/d PO 2 doses) and furosemide (1 mg/kg/dose PO X2) ◼ The dose of digoxin may present signs of toxicity decreases: decreased appetite, frequent vomiting.

Question 34

Chronic HF In more severe forms of HF

Answer 34

◼ furosemide - 2 mg/kg/dose PO X 3/day, or associated with hydrochlorothiazide.

Question 35

Chronic HF Afterload decrease

Answer 35

in patients with large shunts left/right (VSD/PDA), left heart regurgitations or reduced systolic function (myocarditis and dilated cardiomyopathy). ◼ ACE inhibitors are the first choice.

Question 36

Chronic HF About furosemide and potassium

Answer 36

 For each patient who receives furosemide > 1 mg/kgX2/day without ACE inhibitors, this should be associated with spironolactone.  Potassium levels need to be monitored and eventually supplemented orally.

Question 37

Beta-blockers in CHF in children

Answer 37

 beta1-selective blockers - metoprolol  alpha 1/beta 2 blockers - carvedilol  Encouraging results in chronic HF associated with cardiomyopathy, with increasing EF.  Nutrition  Treatment of anemia  Malnutrition is an indicator for medical management or surgical intervetion.

Question 38

Device Therapy for Heart Failure

Answer 38

 Cardiac resynchronization therapy (CRT)  Implantable defibrillators (IDs)

Question 39

CRT:

Answer 39

◼ Clinical improvement, exercise tolerance, quality of life, echocardiographic indices of LV performance, ◼ Increased survival in adults with HF and intraventricular conduction disorder ◼ In adults - recommendations: symptomatic HF and electric dyssynchrony (intraventricular conduction disorder) ◼ In children - study on 7 children with CHD and RBBB with small but significant improvement of CO and dp/dt for RV

Question 40

IDs

Answer 40

◼ In adults - ↓ 30% lower risk of sudden death (SD) in patients with a history of malignant ventricular rhythm disturbancies ◼ There are no guidelines for children ◼ They are recommended in ventricular arrhythmias/resuscitated SD

Question 41

Survival in HF

Answer 41

 It depends on the cause  Structural anomaly - repaired - excellent.  Eg: infants with VSD spontaneously closed/surgically - normal life.  Complex CHD - the results are variable  Cardiomyopathy in elder children tend to progress, unless there is a reversible cause