Cardiac failure Flashcards
Define cardiac failure
when the heart is unable to pump sufficiently to maintain blood flow to meet the body’s needs
What are the presenting features of cardiac failure?
(symptoms and signs)
Symptoms:
- Breathlessness (particuarly on feeding or exertion)
- Sweating
- Poor feeding
- Recurrent chest infections
Signs:
- Poor weight gain or ‘faltering growth’
- Tachypnoea
- Tachycardia
- Heart murmer, gallop rhythm
- Enlarged heart
- Hepatomegaly
- Cool peripheries
What is the normal pulse rate for the ages:
- <1 year
- 2-5 years
- 5-12 years
- >12 years
- <1 year = 110-160 beats/min
- 2-5 years = 95-140 beats/min
- 5-12 years = 80-120 beats/min
- >12 years = 60-100 beats/min
What did you need to do in a cardiovascular examination of a child?
- General inspection - cyanosis
- Clubbing of fingers
- Pulse - rate rhythm, volume
- Inspections - distress, precordial bulge, scars, ventricular impulse
- Palpation - thrill (palpable murmer), apex (4th-5th intercostals space, mid-clavicular line), right ventricular heave (lower left sterna edge) shows ventricular hypertrophy
- Auscultation - heart sounds in four areas (apex, LLSE, ULSE, URSE) and the back. Check for murmers, loud heart sounds, splitting of heart sounds
- Hepatomegaly
- Lung bases
- Femoral pulses
- Blood pressure
What is the most common cause of heart failure in the first week of life?
What does it cause?
Left heart obstruction e.g. coarctation of the aorta
- If the obstructive lesion is very severe then arterial perfusion is by right to left flow of blood via the arterial duct - so called duct-dependent systemic circulation
What happens if the ductus arterious closes and there is an left sided heart obstruction such as coarctation of the aorta?
How can it be treated?
- Closure of the duct rapidly leads to severe acidosis and death
- The ductal patency needs to be restored usually via prostaglandin infusion
After the first week of life what is the most likely cause of progressive heart failure?
Explain how?
Due to a left to right shunt (e.g. VSD, AVSD or large persistant patent ductus arteriosus)
- As pulmonary vascular resistance falls, there is a progressive increase in left to right shunt and increasing pulmonary blood flow
What symptoms will this left to right shunt cause?
How long will they last for?
- Pulmonary oedema and breathlessness
- Symptoms will increase up to the age of about 3 months but may subsequently improve as the pulmonary vascular resistance rises in response to the left to right shunt
What happens if these children are left untreated with a left to right shunt?
- Will develop Eisenmenger syndrome (irreverisbly raised pulmonary vascular resistance)
- Means new shunt will now be right to left
What is Eisenmenger syndrome?
Symptoms?
- Irreversibly raised pulmonary vascular resistance
- Process in which a long-standing left-to-right cardiac shunt causes pulmonary hypertension and eventual reversal of the shunt into a cyanotic right-to-left shunt
Symptoms:
- The teenager is blue (severly cyanosed)
- Other S&S assoicated with heart failure e.g. clubbing, fainting ect.
Causes of heart failure in neonates?
Duct dependent
- Aortic valve stenosis
- Coarctation of the aorta
- Interruption of the aortic arch
- Hypoplastic left heart syndrome
Causes of heart failure in infants?
High pulmonary blood flow
- VSD (ventricular septal defect)
- AVSD (artioventricular septal defect)
- large persistant ductus arteriosus
Causes of heart failure in older children and adolescents?
Right to left heart failure
- Eisenmenger syndrome
- Rheumatic heart disease
- Cardiomyopathy
What are the intial investigations you should do for a child with cardiac failure? (8)
- General examination
- Blood pressures
- Peripheral pulses
- Bloods
- ECG
- Chest x-ray
- Pulse oximetry
- Echocardiogram
How do you treat duct dependent circulations?
- Prostaglandin infusion should be given to maintain and duct patency until the defect can be fixed (surgically)
