Approach to Common Cardiac Emergencies

1. Approach to Common Cardiac Emergencies Agustin E. Rubio, MD Sibley Heart Center Cardiology Children’s Healthcare of Atlanta Emory School of Medicine

2. Topics Cyanosis & Ductal Dependent Emergency Room Diagnoses: Tetralogy of Fallot Hypoplastic Left Heart Syndrome Coarctation of Aorta SVT Shunt Dependent vs Non-shunt Dependent

3. 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

4. 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

5. Cyanosis Typically, 2 g/dL of reduced hemoglobin 5g/dL of reduced Hb ? clinical cyanosis Hb 15 ? cyanosis at 75-80% Hb 20 ? cyanosis at 80-85% Hb 6 ? cyanosis at 45-50%

7. 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

8. Symptoms

9. Tetralogy of Fallot

10. Tetralogy of Fallot

11. Tetralogy of Fallot +/- Cyanosis Small to Nl cardiac silhouette pulmonary vasculature

12. Tetralogy of Fallot “Tet spell” Hyperpnea Worsening cyanosis Disappearance of murmur RBBB pattern on ECG

13. 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

14. Tetralogy of FallotSurgical Options

15. 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

16. 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)

17. Tetralogy of FallotPost-operative Concerns Arrhythmias TOF - 40% increased incidence of lethal arrhythmias Syncopal events- lethal ventricular arrhythmias ??

18. Hypoplastic Left Heart Syndrome

19. HLHS

20. 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

21. HLHS Clinically: Progressive cyanosis and hypoxemia Hx of poor feeding, tachypnea and poor weight gain Cardiovascular shock Severe acidosis Congestive heart failure

22. 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

23. 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

24. 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

25. HLHSNorwood/ Sano shunt Post-operative changes Direct PA communication with RV Uncontrolled PBF Neo-aortic reconstruction Higher diastolic pressures Better coronary perfusion

26. 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

27. Coarctation of Aorta

28. 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

29. Coarctation of Aorta Associations: HLHS Aortic stenosis TOF Truncus arteriosus VSD DORV Turner’s syndrome

30. 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

31. 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

32. Coarctation of Aorta Laboratory Evaluation: CBC & ABG/VBG CMP, Magnesium & Phos Lactate BNP level CXR & 12 lead ECG Blood cultures NIRS probe

33. Coarctation of Aorta Neonatal Coarctation rSR’ in the right precordial leads (V1 & V2) Deep S waves in the lateral leads RAD

34. Coarctation of Aorta Infant Coarctation LVH apparent (left lateral leads) Deep S waves in the right chest Large R waves in lateral leads

35. Coarctation of AortaSurgical repairs

36. 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

37. Tachyarrhythmia:Sinus Tach vs. SVT

38. Clinical Signs of Tachyarrhythmia

39. 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

40. ECG Findings

41. Rhythms

42. Sinus Tachycardia vs. SVT

43. SVT – Hemodynamically Stable

44. SVT – Hemodynamically Unstable

45. Medications for SVT

46. Laboratory Evaluation Electrolytes Calcium, Magnesium & Phosphorus CBC with diff CXR & 12 lead EKG looking for pre-excitation – WPW

47. Shunt Dependent vs. Non-dependent What’s the big deal !!!

48. The Difference Shunt Dependent The only source of PBF = SHUNT Non-Dependent Two sources of PBF = Shunt + some antegrade flow through diminuitive PV

49. 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

50. 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

51. 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

52. 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

53. Miscellaneous What information do we require? 4 extremity BP’s, weight %iles H&P Murmurs Organomegaly Pulses ECG Labs, CXR findings, saturations

54. 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