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Paediatric Cardiology. Dr Ratna Merugumalla Consultant in Emergency Medicine Peterborough City Hospital. Cardiovascular presentations. Collapse The blue baby Syncope Palpitations Chest pain. The normal Heart Rate. The ECG. ECG in a 2 year old. ECGs in children.
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Paediatric Cardiology Dr Ratna Merugumalla Consultant in Emergency Medicine Peterborough City Hospital
Cardiovascular presentations • Collapse • The blue baby • Syncope • Palpitations • Chest pain
ECGs in children • Heart rate >100 beats/min • Rightward QRS axis > +90° • T wave inversions in V1-3 (“juvenile T-wave pattern”) • Dominant R wave in V1 • RSR’ pattern in V1 • Marked sinus arrhythmia • Short PR interval (< 120ms) and QRS duration (<80ms) • Slightly peaked P waves • Q waves in the inferior and left precordial leads.
The normal ECG • QRS variable with age - Newborn 50-80ms, at 16 years 75-115ms • cQTC under 6/12: 490ms, 440ms otherwise • Notched t waves; may be normal in V2&3 • Transient Wenckebach during sleep
The normal ECG • Parameters vary through age • Right ventricular dominance owing to high pulmonary pressures, normalise at ~6/12 • T waves; usually upright in most leads for first 7/7, then downwards in most leads until adolescence. • Upright t waves in childhood may reflect RVH.
Chest pain Common but usually benign presentation 4436 presentations age < 19 yrs over 3 1/2 year period in a tertiary PED in USA • 0.6% deemed cardiac • 37% arrhythmia • 29% pericardial • 17% myocarditis • 13% AMI • 4% PE American Journal of Emergency Medicine Volume 29, Issue 6 , Pages 632-638, July 2011)
Non cardiac chest pain • 56% musculoskeletal • 12% asthma/ wheeze • 8% infection • 6% GI – gastritis and GORD • 4% sickle cell disease
Texidor’s twinge • Precordial catch syndrome: • acute, non-radiating left sided chest pain in an adolescent • occurs suddenly, exacerbated during inspiration and resolves in a few minutes
Syncope • 15-20% all children will have an episode
Syncope Red Flags • History of cardiac disease • Family history of SCD • Recurrent episodes • Exertional • Prolonged LoC • Associated chest pain / palpitations • Medications that can alter cardiac conduction
Sudden Cardiac Death • Myocarditis • HOCM • Cyanotic / Acyanotic congenital heart disease • Valvular heart disease • Complete heart block • WPW, long QT syndrome • Marfan’s syndrome • CAD • Anomalous coronary arteries
Cardiac arrhythmias in children • Likely to be the result rather than the cause of acute illness • Often preceded by hypoxia, acidosis and / or hypotension • Primary cardiac arrhythmias are uncommon
Heart rate Age Bradycardia Tachycardia < 1 y < 80 min-1 > 180 min-1 > 1 y < 60 min-1 > 160 min-1
Bradycardia - causes • Bradyarrythmias rare in structurally normal hearts • Usually pre-terminal following hypoxia and ischaemia • Vagal stimulation • Raised ICP • Poisoning with digoxin/ beta-blockers • Congenital CHB seen in infants of mothers with anti ro and la antibodies
Bradycardia Treatment • Oxygenation • Adrenaline – 10mcg/kg • Atropine - Consider when vagal stimulation e.g. airway instrumentation – 20mcg/kg • Pacing (rarely required)
Narrow QRS complex Broad QRS complex ST VT or SVT SVT Treat as VT Tachycardiardia
ST – Treat the cause • Physiological response: Crying Exercise Anxiety/fear Pain • Compensatory mechanism for: Respiratory failure Hypovolaemia Sepsis Anaemia
Supraventricular Tachycardia • Most common primary cardiac arrhythmia in children • Paroxysmal, regular, narrow QRS complexes • Caused by re-entry mechanism through an accessory pathway or AV conduction system • HR > 220 bpm in infants or > 180 bpm in children
SVT - Management • Valsalva manoeuvre • IV Adenosine 100 mcg/kg 200 mcg/kg maximum 1st dose 6mg, 2nd dose 12mg • Amiodarone in refractory SVT • DC cardioversion – for decompensated children
Ventricular Tachycardia Causes • Congenital HD & surgery • Poisoning (TCAs, Quinidine) • Brugada syndrome / Long QT interval • Renal Disease / Hyperkalaemia
Long QT - congenital Normal QTc < 400ms, > 460 ms abnormal Easiest to reproducibly measure in II & V5 Channelopathy Genetic mutations identifies in 90% familial cases Subtypes 1-14 Risk of torsades and VF May present with syncope (VT), risk greatest with QT > 500ms Ask about family history of syncope, sudden death and epilepsy European registry 1993; 8% 5 yr mortality Treatment with BB
Atrial Flutter and Fibrillation • Rare • Underlying CHD, status post-open heart surgery • Cardioversion in decompensated • In haemodynamically stable children, amiodarone or elective cardioversion
Pre-excitation syndromes • Commonest WPW • Ventricular Pre-excitation in SR, short PR and delta wave • Commonest arrhythmia is orthodromic AV re-entry tachycardia • Antidromic less common
The collapsed infant • Wide differential • Always cover for sepsis Congenital heart disease • May present as lethargy, poor feeding, "not right", cyanosis to complete cardiovascular collapse
Congenital heart disease Foetal PVR>SVR; blood bypasses lungs through ductus arteriosus and foramen ovale DA usually closes 24-36hrs post birth – may be much longer FO closes when left atrium volume increases
Congenital heart disease • Failure of normal development or • Persistence of foetal circulation • 7-9% live births • Acyanotic or Cyanotic heart disease
Acyanotic Heart Disease Cyanotic Heart Disease Tetralogy Transposition Tricuspid atresia TAPVD VSD (25%) ASD PDA PV stenosis CoA AS Hypoplastic left heart HOCM Dextrocardia
Congenital heart disease Common presentations: • Cyanosis • Heart failure • Heart murmur
Cyanosis • Cyanosis – ~4-5g/dL of deoxygenated blood • Cardiac cause – ‘comfortably blue’, worse with crying, minimal improvement with O2 • Primary pulmonary disease; no R-L sats diff • Primary cardiac; 5-10 % R-L sats diff • Sepsis; no diff
Failure • Sweating • Poor feeding • Hepatomegaly • SOB • Creps • Tachycardia
Innocent murmurs • Common in children • Never diastolic • Soft, Short, midsystolic, low intensity • Localised • Often vibratory or musical • Increase with output, (fever) • No thrill/ heave or radiation • Asymptomatic • May resolve in few months • Commonest at lower left sternal edge • Venous hum
Evaluation • Pre-natal (USS) • Family history • Birth history (birth state, trauma, risk infection) • Is this cardiac? (murmur + cyanosis + absent pulses) Pre- and post ductal oxygen saturations ABG 4 limb BP (>10mmHg difference suggests coarctation) ECG CXR Echo
ED management • ABC – sats 75-85% • Correct metabolic acidosis and shock with fluid and bicarb • 2 lines/ UVC if possible • Antibiotics anyway! • Gentle handling • Keep warm • Prostoglandin – ductal patency • Inotropes • Ventilate – in air if possible, PEEP 4-6cmH2O
Prostaglandin • PGE2 infusion (dinoprostone) • In duct dependent lesion • Hyperoxia test suggestive, femoral pulses diminished, metabolic acidosis persistent after volume and inotropes • Ensure antibiotics given! • Beware of apnoea. May cause hypotension, jitteriness and jerks • No absolute contraindications
Prostaglandin Possible Adverse Effects Administration Intravenous infusion Consider intubation Dose 0.01 – 0.1 mcg/kg/min • Apnoea • Hypotension • Hyperthermia (transient) • Tachycardia • Bradycardia • Seizures • Diarrhoea • Skin flush