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Congenital Heart Disease, Cyanotic, Emergency Medicine

Basics

Description

- Eisenmenger syndrome: - Complication in longstanding acyanotic heart disease with L→R shunts - Pulmonary vascular resistance reaches suprasystemic levels; R→L shunt

- Central cyanosis: - Visible in lips, nail beds, mucosa - Increases with cry or agitation - Minimal change with 100% O2

- Hypercyanotic spells or "Tet spells"пїЅ: - Restless and hyperpneic then increased cyanosis then syncope - Follows reductions in already compromised pulmonary blood flow: - Wakening, feeding, vigorous cry, exercise

- TOF: - Often asymptomatic at birth; symptoms develop as RV infundibulum hypertrophies - Severe RV outflow obstruction; neonatal cyanosis (duct-dependent lesion) - Cyanosis during crying or feeding (Tet spells) in toddlers - Older, uncorrected patients: - Dyspnea on exertion and growth delay

- TAPVR: - Neonatal presentation; severely ill: - Cyanosis - Does not improve with mechanical ventilation

- Infantile presentation; heart failure: - If no obstruction to pulmonary venous return: - Asymptomatic or mild cyanosis - Frequent pneumonias - Growth problems

- TOF: - Loud systolic murmur left sternal border (LSB) - Systolic thrill in 50% - +/- Continuous murmur of PDA - Loud, single 2nd heart sound (S2) - RV prominence/bulge - Older, uncorrected patients: - Dusky, blue skin - Clubbing of digits - Retinal engorgement

- Tricuspid atresia: - Tachypnea - Regurgitant murmur from VSD at LSB - +/- continuous PDA murmur - Single S2 - Prominent LV impulse

- Ebstein anomaly: - Holosystolic murmur of tricuspid regurgitation - Many have diastolic murmur - Gallop

- TAPVR: - Neonatal; severe tachypnea and cyanosis - Infantile; heart failure: - Tachycardia - Systolic ejection murmur at LSB - Mid-diastolic murmur at lower LSB - Gallop - Fixed, split S2 - Hepatomegaly

- Older infants; heart failure: - Hyperdynamic precordium - Bounding pulses - Wide pulse pressure - Loud, single S2 - Systolic ejection murmur and thrill - Mid-diastolic murmur

- Neurologic: - Seizure - Neuromuscular disease - Drug-induced respiratory depression

- Other: - Polycythemia - Methemoglobinemia - Dehydration - Hypoglycemia

- Administer prostaglandin E1 (PGE1) to dilate or reopen the ductus arteriosus: - Continuous IV infusion 0.05-0.1 Ојg/kg/min - Complications include apnea, bradycardia, hypotension, and seizures: - Generally intubate prior to transport

- Cyanosis in the older patient with known CHD: - 10-20 mL/kg NS IV if dehydration likely - Supplemental O2 if suspicious for pulmonary diseases - Antipyretics for fever - Antibiotics for pneumonia/infectious process

- Circulatory collapse from CHD: - Fluid resuscitation - Inotropes: Dobutamine, dopamine, milrinone - Aggressive treatment of acidosis

  • Aberrant embryonic development results in mixing of deoxygenated and oxygenated blood returning to systemic circulation by 2 mechanisms:Right-to-left intracardiac shuntAnatomic defects of the aortic root
  • Subtypes: 5 T's, 2 E's, single ventricle:Tetralogy of Fallot (TOF):Ventricular septal defect (VSD)Right ventricular (RV) outflow obstructionOverriding aortaRV hypertrophy (RVH)Transposition of the great arteries (TGA):Aorta arises from RV and pulmonary artery from left ventricle (LV)Tricuspid atresia:No outlet from right atrium to RVObligatory atrial level connectionTruncus arteriosus:Single arterial trunk for systemic, pulmonic, and carotid circulationsTotal anomalous pulmonary venous return (TAPVR):Pulmonary veins drain into systemic venous circulationSupracardiac, cardiac, infracardiac, or mixedEbstein anomaly of tricuspid valve:Abnormal and displaced tricuspid valve divides RV resulting in poor RV functionEisenmenger syndrome:Complication in longstanding acyanotic heart disease with Lв†’R shuntsPulmonary vascular resistance reaches suprasystemic levels; Rв†’L shuntSingle ventricle physiology:Total mixing of systemic and venous return

Etiology

For most forms, cause is unknown пїЅ

Diagnosis

  • Most common initial ED presentations of cyanotic congenital heart disease (CHD):CyanosisCHFCirculatory collapse
  • Physiologic stress triggers cyanosis in older patients with CHD:Cardiac shunt obstructionPulmonary diseaseDecreased systemic vascular resistanceFeverDehydration

Signs and Symptoms

  • Central cyanosis:Visible in lips, nail beds, mucosaIncreases with cry or agitationMinimal change with 100% O2
  • CHF:Rales, gallop, hepatomegaly, scalp edema
  • Hypercyanotic spells or "Tet spells"пїЅ:Restless and hyperpneic then increased cyanosis then syncopeFollows reductions in already compromised pulmonary blood flow:Wakening, feeding, vigorous cry, exercise
  • Older child may compensate by squatting.
  • Temporary reduction or absence of systolic ejection murmur during spell

History

  • Family history of CHD:If parent or sibling: Increased risk of CHDIf 2 relatives: Risk of CHD triples
  • Prenatal history:Exposure to teratogensAbnormal fetal ultrasound
  • TOF:Often asymptomatic at birth; symptoms develop as RV infundibulum hypertrophiesSevere RV outflow obstruction; neonatal cyanosis (duct-dependent lesion)Cyanosis during crying or feeding (Tet spells) in toddlersOlder, uncorrected patients:Dyspnea on exertion and growth delay
  • Tricuspid atresia:Usually cyanotic from birthFeeding difficultiesOlder patients show dyspnea on exertion and easy fatigability
  • Ebstein anomaly:Teens may present with dysrhythmias.
  • TGA:Presents in 1st hr to days of life
  • TAPVR:Neonatal presentation; severely ill:CyanosisDoes not improve with mechanical ventilationInfantile presentation; heart failure:If no obstruction to pulmonary venous return:Asymptomatic or mild cyanosisFrequent pneumoniasGrowth problems
  • Truncus arteriosus:Mild cyanosis in newbornHeart failure in older infants

Physical Exam

  • TOF:Loud systolic murmur left sternal border (LSB)Systolic thrill in 50%+/- Continuous murmur of PDALoud, single 2nd heart sound (S2)RV prominence/bulgeOlder, uncorrected patients:Dusky, blue skinClubbing of digitsRetinal engorgement
  • Tricuspid atresia:TachypneaRegurgitant murmur from VSD at LSB+/- continuous PDA murmurSingle S2Prominent LV impulse
  • Ebstein anomaly:Holosystolic murmur of tricuspid regurgitationMany have diastolic murmurGallop
  • TGA:Single, loud S2Severe hypoxemia
  • TAPVR:Neonatal; severe tachypnea and cyanosisInfantile; heart failure:TachycardiaSystolic ejection murmur at LSBMid-diastolic murmur at lower LSBGallopFixed, split S2Hepatomegaly
  • Truncus arteriosus:Newborn:Mild cyanosisRegurgitant systolic murmur at LSBSingle S2
  • Older infants; heart failure:Hyperdynamic precordiumBounding pulsesWide pulse pressureLoud, single S2Systolic ejection murmur and thrillMid-diastolic murmur

Essential Workup

  • Oxygen saturation
  • ABG
  • CBC, glucose
  • Sepsis evaluation
  • CXR to assess pulmonary blood flow
  • EKG to assess for hypertrophy and QRS axis
  • Cardiology consult and ECG

Diagnosis Tests & Interpretation

Lab

  • Decreased room air oxygen saturation
  • Hyperoxia test:ABG in room air and after several minutes 100% oxygen:PaO2 >150 in O2; no intracardiac shuntPaO2 <100 in O2; highly suspicious of cyanotic CHD
  • CBC: Erythrocytosis with chronic cyanosis

Imaging

  • CXR:Decreased pulmonary blood flow:TOF (enlarged RV)Tricuspid atresia (enlarged LV)Single ventricle physiologyIncreased pulmonary flow:Transposition of the great vessels (large RV)TAPVR (large RV)Truncus arteriosus (large LV and RV)Classic CXR descriptions:Boot-shaped heart: TOF; large and upturned RV looks like toe of bootEgg on a string: TGA; narrow mediastinum, great vessels anterior/posterior positionSnowman sign: Supracardiac TAPVR; upper portion formed by pulmonary veins

Diagnostic Procedures/Surgery

EKG: пїЅ

  • TOF:Right axis deviation (RAD)RVH
  • TAPVR:RADRVH and right atrial enlargement (RAE)
  • Transposition of the great vessels:
  • Tricuspid atresia:Superior axisLVH, RAE, LAE
  • Truncus arteriosus:
  • Ebstein anomaly:Right bundle branch blockOften Wolff-Parkinson-White

Differential Diagnosis

  • Pulmonary:Pneumothorax/hemothoraxBronchopulmonary dysplasiaCongenital lung hypoplasia/dysplasiaPulmonary hemorrhagePulmonary embolusPulmonary HTNDiaphragmatic herniaForeign body/anatomic obstruction
  • Cardiac:Cyanotic CHDCHFCardiogenic shock
  • Infectious:Pneumonia, bronchiolitisSepsis
  • Neurologic:SeizureNeuromuscular diseaseDrug-induced respiratory depression
  • Other:PolycythemiaMethemoglobinemiaDehydrationHypoglycemia

Treatment

Initial Stabilization/Therapy

  • Maintain warmth (cold ↑ O2 consumption).
  • Treat hypoglycemia and acidosis.
  • Maintain oxygenation.
  • Establish IV access.
  • Prepare for endotracheal intubation.
  • High oxygen tensions promote ductal closure.
  • Place air filters on all IV lines to avoid paradoxical emboli through Rв†’L shunt.

Ed Treatment/Procedures

  • Administer prostaglandin E1 (PGE1) to dilate or reopen the ductus arteriosus:Continuous IV infusion 0.05-0.1 Ојg/kg/minComplications include apnea, bradycardia, hypotension, and seizures:Generally intubate prior to transportNot effective for obstructed TAPVR:May require ECMO awaiting surgeryOverall benefits far outweigh potential risks
  • Evaluate and treat alternate causes of cyanosis:Septic workup and empiric antibioticsFluid resuscitate (increments of 10 mL/kg)Maintain normoglycemia
  • Patients with Tet spells:Provide a calming environment.Place child in knee-chest position.Supplemental O2 if not agitating to patientIV or IM morphineFor severe cases not responding to above:IV bicarbonate to treat severe acidosisIV phenylephrine to ↑systemic vascular resistance and reduce Rв†’L shuntIV propranolol for β-adrenergic blockade
  • Cyanosis in the older patient with known CHD:10-20 mL/kg NS IV if dehydration likelySupplemental O2 if suspicious for pulmonary diseasesAntipyretics for feverAntibiotics for pneumonia/infectious process
  • Circulatory collapse from CHD:Fluid resuscitationInotropes: Dobutamine, dopamine, milrinoneAggressive treatment of acidosis

Medication

  • Acetaminophen: 15 mg/kg PO or PR
  • Ampicillin: 50 mg/kg IV
  • Dobutamine: 5-20 Ојg/kg/min IV
  • Dopamine: 5-20 Ојg/kg/min IV
  • Gentamicin: 4 mg/kg/d IV or 2.5 mg/kg/dose
  • Ibuprofen: 10 mg/kg PO (>6 mo)
  • Milrinone: 0.25-1 Ојg/kg/min
  • Morphine sulfate: 0.1 mg/kg SC, IM, or IV
  • Phenylephrine: 0.5-5 Ојg/kg/min IV
  • Propranolol: 0.1 mg/kg IV
  • PGE1: 0.05-0.1 Ојg/kg/min
  • Sodium bicarbonate: 1-2 mEq/kg IV

Follow-Up

Disposition

Admission Criteria

  • All newborns with suspected CHD:
  • CHD with acute worsening of cyanosis or CHF
  • CHD with symptomatic pneumonia or respiratory syncytial virus

Discharge Criteria

  • Determine in consult with cardiologist
  • Patients who respond to minimal intervention (i.e., TOF patients treated noninvasively)
  • Ensure close follow-up.

Issues for Referral

  • Primary care physician to coordinate care
  • Cardiologist for diagnosis, medical management, and ongoing monitoring
  • Cardiothoracic evaluation for surgery

Follow-Up Recommendations

  • Plan for follow-up should be determined in consult with the pediatric cardiologist.
  • Clear instructions for return visits, as any physiologic stress may worsen condition.

Pearls and Pitfalls

  • Visual appearance of cyanosis requires >3-5 mg/dL deoxygenated hemoglobin.
  • Duct-dependent lesions:Present at 2-3 wk of ageSudden cyanosis or cardiovascular collapseTreat with PGE1:Beware apnea and hypotension

Additional Reading

  • Apitz пїЅC, Webb пїЅGD, Redington пїЅAN. Tetralogy of Fallot. Lancet. 2009;374:1462-1471.
  • Bonow пїЅRO, Mann пїЅDL, Zipes пїЅDP, et al., eds. Congenital heart disease. Braunwalds Heart Disease. 98th ed. Philadelphia, PA: Saunders Elsevier; 2012:1411-1467.
  • Dolbec пїЅK, Mick пїЅN. Congenital heart disease. Emerg Med Clin North Am. 2011;29:811-827.
  • Fleisher пїЅGR, Ludwig пїЅS, Bachur пїЅRG, et al., eds. Cardiac emergencies. Textbook of Pediatric Emergency Medicine. 6th ed. Philadelphia, PA: Lippincott Williams, & Wilkins, 2010:690-701.
  • Yee пїЅL. Cardiac emergencies in the first year of life. Emerg Med Clin North Am. 2007;25:981-1008.

Codes

ICD9

  • 745.2 Tetralogy of fallot
  • 745.4 Ventricular septal defect
  • 746.89 Other specified congenital anomalies of heart
  • 747.21 Anomalies of aortic arch
  • 429.3 Cardiomegaly
  • 745.10 Complete transposition of great vessels

ICD10

  • Q21.0 Ventricular septal defect
  • Q21.3 Tetralogy of Fallot
  • Q24.8 Other specified congenital malformations of heart
  • Q25.4 Other congenital malformations of aorta
  • I51.7 Cardiomegaly
  • Q20.3 Discordant ventriculoarterial connection

SNOMED

  • 12770006 cyanotic congenital heart disease (disorder)
  • 86299006 Tetralogy of Fallot (disorder)
  • 30288003 Ventricular septal defect (disorder)
  • 253530007 right ventricular outflow tract obstruction (disorder)
  • 204296002 Discordant ventriculoarterial connection
  • 63934006 Overriding aorta (disorder)
  • 89792004 right ventricular hypertrophy (disorder)