common cardiac emergencies agustin e. rubio, md sibley heart center cardiology children’s...
TRANSCRIPT
Common Cardiac Emergencies
Agustin E. Rubio, MDSibley Heart Center CardiologyChildren’s Healthcare of Atlanta
Emory School of Medicine
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Topics
• Cyanosis & Ductal Dependence• Emergency Room Diagnoses:
Tetralogy of FallotHypoplastic Left Heart SyndromeCoarctation of AortaSVT
• Shunt Dependent vs Non-shunt Dependent
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Epidemiology
Cardiac malformations • 10% of infant mortality
Incidence:• 4-6/1000 live births
Most common lethal diagnosis:• Left ventricular outflow tract obstruction
Hypoplastic left heart syndrome Coarctation of aorta Aortic stenosis
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Circulatory Transitions
Conversion from right sided (placental oxygenation) to left sided circulation (pulmonary oxygenation)
Progression is secondary:• Decreasing PVR• Closure of ductal shunts
Clinical presentations:• Cyanosis• Respiratory failure• Shock
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Cyanosis
Typically, 2 g/dL of reduced hemoglobin• 5g/dL of reduced Hb clinical cyanosis
The higher the Hb the less likely to have severe cyanosis
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Ductal Dependent Lesions
Cyanosis CHF/Shock
Rt to Lt shunting:
Tricuspid atresia
TOF/ Pulm atresia
Ebstein’s anomaly
Lt Ventricular Outflow Tract Obstruction:
HLHS
Coarctation of Aorta/ AS
Truncus arteriosus
TGA with VSD
TAPVR
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Left Ventricular Outflow Tract Obstruction
Major source of neonatal M&M from CHD • Accounts for ~ 12% of congenital cardiac
disease in infancy• ~ 75% discharged from hospital w/o
diagnosis• ~ 65% - normal newborn screen
examination• 6% died before diagnosis• 96% symptoms by 3 wks of life
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Symptoms in Real-Time
Timeline of Clinical Diagnosis
Week #1 HLHS
Coarctation of aorta
TAPVR - obstucted
Week #2-6 Transposition of Great Arteries
Total Anomalous Venous Return
Truncus arteriosus
Tetralogy of Fallot
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Tetralogy of Fallot
Prevalence: - 10% of CHD
Most common cyanotic heart defect beyond infancy
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Tetralogy of Fallot
+/- Cyanosis
Small to Nl cardiac silhouette
pulmonary vasculature
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Tetralogy of Fallot
“Tet spell”• Hyperpnea• Worsening
cyanosis• Disappearance of
murmur• RBBB pattern on
ECG
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Tetralogy of Fallot
“Tet spell”• Treatment objectives:
Reverse the right-to-left shunt systemic vascular resistance (SVR) Correct potential acidosis with NaHCO3 &
volume Consider peripheral vasoconstriction
(phenylephrine – 0.02 mg/kg IV) Ketamine
– increase SVR and sedates 2 mg/kg over 1 min Morphine sulphate Oxygen
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Tetralogy of FallotSurgical Options
Trans-annular patch
VSD closure
Blalock-Taussig shunt
Delayed repair
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Tetralogy of FallotPost-operative Concerns
• Post-pericardiotomy syndrome ~ 4 weeks post-op (25-30% of open heart pts) Fever, elevated ESR and CRP Increased work of breathing (? pericardial
effusion) Cardiomegaly, pleural effusions ECG – persistent ST segment elevation with
flat or inverted T waves in limb & left lateral limb leads
Pericardiocentesis – performed when tamponade physiology present
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Tetralogy of FallotPost-operative Concerns
• Endocarditis Dx after >2 BCx or echo evidence
• Residual VSD• Arrhythmias
AV block, ventricular arrhythmias
• Remember: Any incision in the ventricle produces a
RBBB pattern (rSR’ in V1; wide complex QRS)
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Tetralogy of FallotPost-operative Concerns
Arrhythmias• TOF - 40% increased
incidence of lethal arrhythmias
• Syncopal events- lethal ventricular arrhythmias ??
Hypoplastic Left Heart Syndrome
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HLHS
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HLHS
Uncommon form of cyanotic heart disease
Most common cause of death in the first month of life
Critically ill infant within the first 7 days with low O2 saturations
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HLHS
Clinically:• Progressive cyanosis and hypoxemia• Hx of poor feeding, tachypnea and poor
weight gain• Cardiovascular shock• Severe acidosis• Congestive heart failure
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Consequences and Complications
Polycythemia (erythrocytosis) Clubbing (>6 mos of age) Hypoxic spells CNS
• Cyanotic heart disease accounts for 5-10% of brain abscesses
• Cerebral venous thrombosis - <2 yrs, cyanotic and microcytic anemia
Dyscrasias
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HLHSPre-operative Resuscitation
Medical management:• Intubation• Ventilate and oxygen• Intravenous access
Central/ umbilical/ intra-osseos• Glucose• Na HCO3
• PGE1 (get that PDA open!!)
PGE1 0.05 mcg/kg/min
• Volume – NS/ 5% Albumin/ PRBC’s• NIRS probe
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HLHSNorwood/ Blalock-Taussig Shunt
Post-operative changes• Uncontrolled PBF
• Re-constructed aortic outflow tract
• Fluid balance sensitive
• Widened pulse pressures
• Tenuous coronary circulation
• Single ventricle for all circulation
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HLHSNorwood/ Sano shunt
Post-operative changes• Direct PA
communication with RV• Uncontrolled PBF• Neo-aortic
reconstruction• Higher diastolic
pressures• Better coronary
perfusion
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HLHSPost-Operative Resuscitation
Limit oxygen (remember: relative uncontrolled PBF) Hemoglobin Auscultate for murmur:
• Continuous murmur at RUSB (? BT shunt)• Systolic murmur at RLSB/ LUSB (Sano shunt)
Fluid balance:• Palpate liver • +/- rales and CXR to evaluate for CHF• Reverse dehydration
Reverse acidosis
Coarctation of Aorta
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Coarctation of Aorta
Common cause of left sided heart failure
95% located in juxtaductal region
Associated with other congenital anomalies
May be short segments or long segments
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Coarctation of Aorta
Associations:• HLHS
• Aortic stenosis
• TOF
• Truncus arteriosus
• VSD
• DORV
• Turner’s syndrome
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Coarctation of Aorta
Clinical• Poor feeding, dyspnea & poor weight gain• Upper arm vs lower extremity BP
discrepancy >10-20 mmHg systolic upper vs. lower 20-30% develop CHF by 2-3 months
• Hx of lower extremity weakness or pain after exercise
• 50% will have no murmur
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Coarctation of Aorta
Acute clinical presentation:• Cardiovascular shock
Somnolent & lethargic Poor po intake/ dehydrated, poor U/O Cold, clammy & diaphoretic Poor pulses +/- organomegaly Bradycardia/ tachycardia
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Coarctation of Aorta
Laboratory Evaluation:• CBC & ABG/VBG
• CMP, Magnesium & Phos
• Lactate
• BNP level
• CXR & 12 lead ECG
• Blood cultures
• NIRS probe
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Coarctation of Aorta
Neonatal Coarctation• rSR’ in the right precordial leads (V1 &
V2)• Deep S waves in the lateral leads• RAD
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Coarctation of Aorta
Infant Coarctation• LVH apparent (left lateral leads)• Deep S waves in the right chest• Large R waves in lateral leads
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Coarctation of AortaSurgical repairs
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Coarctation of AortaPost-operative State
Re-coarctation• Occurs most commonly within the first 12
months• Evaluated by 4 extremity BP’s• Physical examination of upper & lower
extremity pulses
Tachyarrhythmia:Sinus Tach vs. SVT
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Clinical Signs of Tachyarrhythmia
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Symptoms from History
Neonate: • Sudden onset of
irritability& sudden relief
• Poor po intake & somnolence
• Inconsolable• “Rapid heart
beat”– felt by parents
Older Child:• Stops activity
abruptly• “Palpitations”/
“feels funny”• Sudden relief with
vasovagal manuever
• Chest pain - rare
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ECG Findings
Sinus Tach
Sinus Tach
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Rhythms
SVT
Sinus Tach
Regular rhythm, narrow QRS, HR >200, p buried in T wave
Regular rhythm <200, distinct p waves, nl intervals
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Sinus Tachycardia vs. SVT
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SVT – Hemodynamically Stable
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SVT – Hemodynamically Unstable
** Cardioversion should be performed in a location which can provide for continuous monitoring and potential complications of sedation.
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Medications for SVT
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Laboratory Evaluation
Electrolytes• Calcium, Magnesium & Phosphorus
CBC with diff
CXR & 12 lead EKG
• looking for pre-excitation – WPW
Shunt Dependent vs. Non-dependent
What’s the big deal !!!
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The Difference
Shunt Dependent• The only source of PBF = SHUNT
Non-Dependent• Two sources of PBF = Shunt + some
antegrade flow through diminuitive PV
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Shunt Dependent
Oxygen therapy• Limit O2 therapy for cyanosis• Maintain sats 75-85%• Sats can drop significantly and quickly
• If sats >85%: PVR PBF Pulmonary edema
and circulatory shock
• Use blended O2 with range of up to FiO2 0.4
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Non-Dependent
Oxygen therapy• Two sources of PBF:
One with fixed obstruction and the other is uncontrolled
• If BT shunt present: Limit O2 O2 saturations should not drop as far nor as
quickly
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Summary
CHD &/or arrhythmias should be suspected neonates with cardiovascular shock
Evaluation should include:• CBC, cultures, electrolytes, lactate levels, Blood
gases• CXR, 12 Lead EKG
H&P provide 90% of diagnoses
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Medical Management
Airway, Breathing, Circulation
What disease and what was the repair?
Prostaglandins• 0.03 to 0.1 mcg/kg/min• Side effects:
Hyperpyrexia Apnea Flushing
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Miscellaneous
What information do we require?• 4 extremity BP’s, weight %iles
• H&P Murmurs Organomegaly Pulses ECG Labs, CXR findings, saturations
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Sources
Internet websites:• www.childrenshospital.org• www.cincinattichildrens.org• www.ucsfhealth.org/childrens/
Pediatric Cardiology for the Practioners. MK Park 4th ed.
Congenital Heart Disease - Moss and Adams