1. Bradley S. Marino, MD, MPP, MSCE
Critical Congenital Heart Disease in the Newborn: Anatomy, Physiology and Surgical Management
Bradley S. Marino, MD, MPP, MSCE
Associate Professor of Pediatrics Staff Cardiac Intensivist, Cardiac Intensive Care Unit The Divisions of Cardiology and Critical Care Medicine Cincinnati Children’s Hospital Medical Center University of Cincinnati College of Medicine

2. Background Congenital Heart Disease 8/1000 live births
“Critical” CHD 3/1000 live births
Death
- Cardiac catheterization
- Surgery

3. Scope of the Problem In the USA: ~ 32,000 children born/year with CHD
~ 11,000/year with “Critical” CHD
~ 150,000 children in US school system with “repaired” CHD

7. CHD Presenting in the Neonatal Period
0-6 days days days
(n=1603) (n=311) (n=306)
TGA (15%) Coarct (20%) VSD (18%)
HLHS (12%) VSD (14%) TOF (17%)
TOF (8%) HLHS (9%) Coarct (12%)
Coarct (7%) TGA (8%) TGA (10%)
VSD (6%) TOF (7%) PDA (5%)
Other (52%) Other (42%) Other (38%)

8. Clinical Presentation of CHD in the Neonate
Fetal Diagnosis
Cyanosis
CHF/Shock/Circulatory Collapse
Arrhythmia
Asymptomatic Heart Murmur

9. Clinical Presentation of CHD in the Neonate
Timing and Symptoms depend on
(1) anatomic defect
(2) in utero effects (if any)
(3) physiologic changes – transitional circulation
closure of the ductus arteriosus and
fall in pulmonary vascular resistance

10. Newborn Presentation of CHD
Cyanosis
- Usually minimal symptoms
- First hours of life
- Duct-dependent pulmonary blood flow
- Mixing lesion:
TGA, TAPVC, Truncus Arteriosus
CHF/Circulatory Collapse/Shock
- First 2 weeks of life
- Duct-dependent systemic blood flow
- Secondary end-organ dysfunction
Heart, Brain, Kidneys, GI

11. Evaluation of the Cyanotic Neonate
Cyanosis occurs if there is >3.0g/dL of deoxygenated hemoglobin:
ambient lighting
skin color
hemoglobin; for O2 saturation of 80%
if Hg is 20 gm/dl; 4 gm desaturated-visible cyanosis
if Hg is 10 gm/dl; 2 gm desaturated-not cyanotic
Hyperoxia Test to Determine Intrapulmonary vs. Intracardiac Shunt

12. Neonatal Presentation-Cyanosis Hyperoxia Test
Room air (if tolerated)
pO2 directly measured or TCOM
100% FIO2 - “blow-by”, mask, intubated
Repeat mesurement of pO2 right radial artery
Must note site of measurement
Pulse oximetry not acceptable

13. Hyperoxia Test - Interpretation
pO2 < 100; cyanotic CHD likely
pO ; cyanotic CHD possible
pO2 > 250; cyanotic CHD unlikely
A “failed” hyperoxia test is a neonatal emergency - urgent intervention.

14. CHD in the Neonate - Cyanosis
For PO2<50 there is a limited number of
diagnoses possible
Chest Xray VERY Helpful
Massive Cardiomegaly = Ebstein’s Anomaly
Pulmonary Edema = TAPVC
Increased PBF = d-TGA with IVS
Decreased PBF right sided obstructive
lesion with intracardiac R to L shunting

15. CHD in the Neonate - Cyanosis PO2<50 with Decreased PBF
ECG and Cardiac Exam
Tricuspid Atresia with PS vs
Tricuspid Atresia/Pulmonary Atresia
Tetralogy of Fallot vs
Tetralogy of Fallot/Pulmonary Atresia
Pulmonary Stenosis vs
Pulmonary Atresia with IVS

16. Cyanotic Congenital
Heart Disease
“Right Sided”
Early Presentation

17. VSD-PS;
if severe- may require
open PDA for PBF

18. Ebstein’s Anomaly In-utero TR hydrops SVT common Sub PS from TV tissue
iNO helpful to lower
PVR and encourage
antegrade PBF

19. Pulmonary Atresia-Intact Ventricular Septum
Suprasystemic RV
pressure TR
CoronarySinusoids

20. RV-Coronary Connections
in PA-IVS

21. “Critical” Pulmonary Stenosis
-“Duct-Dependant” PBF
-Non-compliant RV
-RL atrial shunt through ASD or PFO

22. - Anterior Malalignment VSD - Aortic Override - Sub PS - RVH 25% 22q11
Microdeletion

23. Anterior Malalignment VSD
Tetralogy of Fallot-
Anterior Malalignment VSD

24. Severe Sub PS in TOF with Hypoplastic PAs

25. Truncus Arteriosus Conotruncal Defect VSD Abnormal Truncal Valve
Single Great Artery
Gives Rise to:
coronary arteries
pulmonary arteries
brachiocephalic arteries
35% 22q11 Microdeletion

26. Profound hypoxemia
Low pO2
High pCO2
-Shock in the first 48 hours
CXR-small heart, white lungs

27. Supracardiac TAPVR
Lateral Angiogram

28. Survival Dependant Upon Mixing Between Systemic and Pulmonary Circuits
(PFO, VSD, PDA)
- 40% with VSD
- PDA PGE1
Balloon Atrial
Septostomy in most
cases of TGA/IVS

29. Balloon Atrial Septostomy-Cath

31. Clinical Presentation of CHD in the Neonate
Cyanosis
Congestive Heart Failure
Asymptomatic Heart Murmur
Arrhythmia

32. Congestive Heart Failure
Clinical Syndrome marked by inability of the heart to meet the metabolic demands of the body
After the first hours of life, the neonate with CHF/shock has duct-dependent, left-sided heart disease until proven otherwise
Coarctation of the Aorta
Interrupted Aortic Arch
Critical Aortic Stenosis
Hypoplastic Left Heart Syndrome (HLHS)

33. Congestive Heart Failure
CHF may be the result of:
Increased demand
- volume or pressure overload
Normal demand but decreased
function
- Inflammatory or metabolic
disease

34. CHF/Shock in the Neonate
Evaluation for and treatment of
presumptive sepsis should be
undertaken simultaneously.

35. Upon Closure of PDA: - acute  LV afterload -  gut, renal perfusion
- CHF and acidosis

36. Posterior Malalignment VSD:
Sub-Aortic Stenosis
- 75% 22q11 Microdeletion

37. Interrupted Aortic Arch
AP View
Lateral View
Restrictive PDA

38. LV dysfunction in utero
Endocardial
Fibroelastosis (EFE)
PDA necessary for
systemic perfusion
PFO necessary for
PV return to reach
systemic circulation

39. 1/5000 Live Births
Lower Body, CNS and Coronaries Dependant Upon Patent Ductus

40. Profound CHF-Shock Upon Ductal Closure
NEC
Hypoxic-Ischemic
CNS Damage
Myocardial Failure

41. CHF/Shock--Metabolic Acidosis
Usually due to decreased tissue perfusion
rather than hypoxemia
Multifactorial - closing PDA, myocardial dysfunction, shunting of systemic circulation into lungs
Treatment:
NaHCO3/Inotropic Support/Sedation/Paralysis
PGE1

42. Physiology of HLHS Qs Qp SVC IVC atrial septum RA SINGLE VENT LA LV pv
Let me take you through the physiology of HLHS.
Systemic venous return enters the RA. In the absence of a patent mitral valve, or if the LV or aorta cannot allow for normal egress of blood, pulmonary venous return will obligatorily exit the LA via the atrial septal communication. Systemic venous blood and pulmonary venous blood then mix in the RA. Further mixing occurs as the 2 flows enter the single vent (RV). With contraction of the RV, blood enters the MPA and may take one of 2 routes: it may descend the ductus arteriosus and perfuse the body, or it may go to the lungs via the branch pulmonary arteries. Obviously both systemic flow to the body and pulmonary flow to the lungs are necessary for survival, however any one blood cell that goes to the lung is one that does not perfuse the body and vice-versa. Hence the key management of this physiology is creating an appropriate balance and distribution of blood flow bbetween the 2 parallel circuits .
What are the Factors influencing the distribution of blood flow?
One may think of this set-up in terms of a pump and 2 resistors. There are variable resistors and fixed resistor in this set-up.
Variable resistors: 1) Ductus Arterious, constriction, 2) SVR (sepsis lowers svr, unnecessary pressors increase SVR, as does oxygen)
3) PVR : with PVR continues to drop and is progressively lowewr than SVR, hence pulm overcirculation is the rule (lung function, atelectasis, pneumonia, RDS, prematurity, oxygen)
Fixed Resistors: anatomic
4) pulmonary venous connection and atrial septal morphology
Discuss arterial blood gases and mixed venous saturations, Barnea paper
SVC
IVC
atrial
septum RA
SINGLE VENT LA LV pv Qp
LUNGS
(PVR) PA
PDA-Ao
BODY
(SVR) Qs

43. Critical CHD Is Suspected
Hyperoxia Test indicates Cyanotic CHD (Ductal Dependent PBF) or Shock >48 hours of age (Ductal Dependent SBF) – Heart Disease Likely
- PGE mcg/kg/min
- Observe minutes
- Repeat ABG and Vital Signs
- Umbilical lines

44. Side Effects of PGE-1 By Birth Weight
<2 >2
KG KG
______________________________________
CV 37% 17%
CNS
Respiratory
Metabolic 5 2
Infectious GI
Hematologic 5 2
Renal 0 2

45. Prostaglandin E1 Apnea Vasodilation/Hypotension Fever Seizures (rare)
May “unmask” CHD with obstruction to PV return
TGA with intact atrial septum
TAPVR
Mitral atresia with small PFO (DORV/MA, HLHS)

47. Supplemental O2 in Critical CHD
Oxygen is a potent pulmonary vasodilator
In lesions with duct-dependant systemic or
pulmonary blood flow (~80% of critical CHD)
Lowering PVR “steals” systemic cardiac
output through PDA
PBF increases at the expense of SBF
As systemic oxygen saturation increases,
systemic oxygen delivery decreases

48. Supplemental O2 in Critical CHD
If systemic cardiac output is normal
If hemoglobin and O2 consumption are normal
An oxygen saturation of ~75-85% provides
adequate oxygen delivery to prevent metabolic
acidosis
Titrate supplemental O2 to saturation ~ 80%

49. Perioperative Management
Initial Stabilization
Airway management
Vascular Access
Newborns-maintenance of PDA
Echocardiographic Diagnosis
Evaluation and Treatment of Secondary Organ Dysfunction
Cardiac Catheterization, if necessary
Surgical Management

50. The Neonate with Critical CHD Echocardiography
Anatomic and Physiologic Assessment
Serial Changes
Not “Non-Invasive”
- Temperature Instability
- Subcostal View
- Suprasternal Notch View - ? Airway Compromise
- Time Consuming

51. Echo is not
“non-invasive” in
the sick neonate

52. Evaluation of Other Organ Systems
Genetics
dysmorphism
multiple congenital anomalies (25% of CHD)
conotruncal malformations
A-V canal malformations (T21)
diffuse arteriopathies (Williams)

53. Evaluation of Other Organ Systems
Central Nervous System
Hypoxia-ischemia at Presentation
Multiple Congenital Anomalies
Seizures
Prematurity

54. Evaluation of Other Organ Systems
Renal (3-6% CHD)
Two Vessel Cord
VACTERL association
Gastrointestinal (1-3% CHD)
Necrotizing enterocolitis
Malrotation (heterotaxy)
Functional Asplenia (heterotaxy)
Duodenal Atresia (Trisomy 21)
Esophageal Atresia (VACTERL)

55. Conclusion Critical CHD 1/300 live births
Cyanosis Right-sided lesions or Mixing Lesions
CHF/Shock  Left-sided lesions
The term neonate who presents with
CHF/shock after the first hours of life has duct-dependant CHD until proven otherwise
PGE1 necessary in ~80% of critical CHD
Titrate supplemental O2 to saturation ~ 80%