Congenital Heart Disease

1. Congenital Heart Disease J.B. Handler, M.D. Physician Assistant Program University of New England

2. ASD- atrial septal defect VSD- ventricular septal defect PDA- patent ductus arteriosus PS- pulmonic stenosis HF- heart failure; aka CHF- congestive heart failure SAP- systolic arterial pressure RV- right ventricle LV- left ventricle PA- pulmonary artery PAH- pulmonary arterial hypertension LVSP- left ventricular systolic pressure PFO- patent foramen ovale LAE- left atrial enlargement PVOD- pulmonary vascular obstructive/occlusive disease PuVR- pulmonary vascular resistance SVR- systemic vascular resistance (same as TPR, PVR) CO- cardiac output PAPVC- partial anomolous pulmonary venous connection Sx- symptoms Qp/Qs- pulmonary blood flow/systemic blood flow LLSB- lower left sternal border RVSP- right ventricular systolic pressure PFO- patent foramen ovale MCA- middle cerebral artery Abbreviations

3. Incidence and Etiology • 8 per thousand births- one third with critical disease. • Majority (>80% survive to adulthood)

4. Incidence -Specific Defects • VSD - 28% • Pulmonic Stenosis - 9.5% • Tetralogy of Fallot- 8-10% (complex ConHD) • PDA - 8.7% • ASD - 6.7% • Coarctation of the Aorta - 4.4% • Aortic Stenosis - 4.4% • Congenital Coronary Anomalies - 1.2%

5. Complications-CHD • HF (aka CHF): May be early in life depending on the defect and it’s severity. HF as adult with milder forms of congenital heart disease if not corrected. • Cyanosis: Common with defects that result in RL shunting of blood. Also occurs in presence of severe hypoxemia from other causes (e.g severe HF). • Clubbing of fingers occurs when cyanosis is long standing. • Hypoxemia from HF responds to O2; hypoxemia from RL shunting does not.

6. Clubbing of Fingers Images.google.com

7. Complications of CHD • Polycythemia: Hct >60 common with RL shunting and associated chronic hypoxemia. • Paradoxical Emboli: Venous thrombus ends up in systemic circulation. See below. • Stroke: • Polycythemia from R-L shunting can lead to direct intracranial thrombosis. • Paradoxical embolus as noted. • Retardation of growth

8. Additional Complications-CHD • Pulmonary Arterial Hypertension (PAH)-Direct transmission of SAP to RV or PA via a large communication (e.g. VSD, PDA). • Pulmonary Vascular Obstructive Disease (PVOD)-Destruction of pulmonary vascular (arteriolar) bed in presence of continuous pressureoverload (muchless common with volume overload alone); results in marked increase in PuVR and furtherelevation of PAP.

9. Ventricular Septal Defect • An opening in that part of the ventricular septum that separates the two ventricles. • 80% involve the thin membranous septum. • 20% involve the muscular septum. • Isolated vs complex lesions • Assoc. conditions: Coarct. of the Aorta, ASD, PDA, sub-aortic stenosis

10. VSD Images.google.com

11. Abnormal Physiology (VSD) • Small “restrictive” VSD: large resistance to flow through small hole; normal RVP and PAP; small L to R shunt; well tolerated. • Mod/large VSD’s allow varying transmission of LVP into the RVPA. PAH common and PVOD develops over time. Large defects result in LV dilation and failure.

12. Clinical Manifestations (VSD) • History: Varies depending on size of defect. • Small VSD- no symptoms; murmur appears within 36 hrs of birth; intensity may change with age. • Larger defects- HF early in life; surgical repair indicated. • Small defect- Possible systolic thrill at LLSB; nl S2; harsh holosystolic murmur along LSB. • Large defect: signs and symptoms of heart failure.

13. Investigative Findings (VSD) • CxR: variable findings reflect severity of shunting. When severe, cardiomegaly, enlarged PA, HF. • ECG: variable findings depending on severity and duration. • Echo-Doppler - diagnostic; identifies the size and location of the defect and presence of shunting; RV and PA pressures can be estimated .

14. Natural History (VSD) • Majority of VSDs are small; 24% close spontaneously by 18 mos, 50% by 4 yrs, more by 10 yrs. Larger defects may become smaller but do not close. • HF occurs in 80% of infants with large VSD. Risk of PVOD is high in moderate to large defects. • Risk of endocarditis if defect remains open (regardless of size). But…. endocarditis prophylaxis with antibiotics no longer indicated; risk of antibiotics outweighs benefits.

15. Management (VSD) • Medical: with small VSD need regular follow up; periodic echo-doppler study will confirm closure. • Moderate and large VSD: treat HF as in adults; surgical repair once HF improved. • Timing of surgery dependent on severity of shunt, LV function and PAP; closure in early childhood years when PAP remains elevated. • With most VSD’s primary closure or a patch can be placed surgically with <1% mortality; normal life expectancy if done early in life, before developing PVOD. Catheter based techniques for closure are evolvingpromising.

16. VSD: Long Term Complications • If PAH continues over time  progressive, irreversible PVOD develops and surgery carries high mortality, with little if any benefit. • In presence of significant PVOD: PuVR and PAP rise dramatically. This can lead to shunt reversalR to L shunting hypoxemia and Rt sided heart failure (Eisenmenger’s physiology/complex).

17. Case 1 • A 31 y/o professional football player returns from Hawaii (long plane flight) following the Pro Bowl (2004). On returning home he has sudden onset of numbness and weakness in his left arm (LA) and leg (LL) along with a small visual field defect. • PE: Healthy man, anxious. Neuro: sensation and strength in LA>LL; reflexes on left side. Legs: bruising of rt calf and thigh. • MRI: rt hemispheric stroke (MCA territory) • Venous ultrasound: Inconclusive; ? thrombus in RLE • What is going on here?

18. Atrial Septal Defect • A through and through communication between the atria at the septal level. • Pathology: Large enough defect to allow free communication between the atria. • Most common form (previously undetected) of CHD in adults; female to male ratio is 2:1. • Atrial septum formed by fusion* of 2 overlapping planes of tissue during fetal development. Most ASD’s occur in mid septum due to lack of tissue for overlap. *Lack of fusion occurs in up to 25% of adults leaving a “patent foramen ovale”, a potential space/opening between the two atria.

19. Patent Foramen Ovale

20. ASD Images.google.com

21. Anatomic Types of ASD • Ostium secundum -defect in mid septum at the fossa ovalis (80%) from incomplete development. • Associated partial anomalous pulmonary venous connection is not uncommon; MVP present in some. • Ostium primum- defect in lower atrial septum; usually associated with additional defects. • Sinus venosus defect (6%) - defect high in the atrial septum.

22. Conditions Common to all ASDs • RA, RV and PA enlarge - volume overload • Pulmonary HTN usually occurs late (3rd or 4th decade) if lesion goes undetected up to that time in life; result of chronic volume overload x years. • PVOD uncommon • Why left to right shunting?

23. Abnormal Physiology (ASD) • L to R shunting at atrial level due to: Rt atrium more distensible than left RV more compliant than LV PuVR <SVR • Hemodynamic burden: RV volume overload and increased pulmonary blood flow; well tolerated for many years.

24. Clinical Presentation (ASD) • Majority of children are asymptomatic • Symptoms when present include fatigue, dyspnea, decreased stamina and usually begin in early 20’s. • Most adults become increasingly symptomatic by 3rd or 4th decade: fatigue, dyspnea and atrial arrhythmia’s (Afib). • “Paradoxical emboli” can result in stroke: Tedi Bruschi, NE Patriots. Venous embolusRA through PFO* LALVRt carotidMCA. *Patent foramen ovale: incomplete fusion of atrial septum (tiny defect) allows clot to pass from RA to LA

25. Physical Exam (ASD) • Hyperdynamic RV (lift): RV volume increase leads to contraction via Starling mechanism. • S1 accentuated at LLSB • S2 widely split through inspiration/expiration: RV ejection is delayed from volume overload. • Grade II-III midsystolic creshendo-decreshendo mumur, at upper LSB reflects increased blood flow across pulmonic valve. Present during childhood.

26. Investigative Findings • ECG: rsR’ pattern in Rt precordial leads with mildly widened QRS (incomplete RBBB); arrhythmias common in adults-Afib, Aflutter. • Echo-Doppler: RV volume overload; enlarged RV, RA; 2D echo and doppler identify the defect and semi quantitate the shunt. • Cardiac cath: Measurement of RV/PA pressures; quantification of shunting; identification of anomalous pulmonary veins if present. Closure of ASD often performed percutaneously using catheters/devices.

27. Natural History and Prognosis • Defect often missed in childhoodlisten for murmurs. • A systolic ejection murmur is the usual reason for further evaluation (echocardiogram or consult). • Sx often begin in late teens and 20’s if large ASD • PA pressures start to rise in early 20’s • Incidence of Atrial Fibrillation and Flutter increases each decade. • Heart failure (Rt sided) and premature death occur in adults without surgery.

28. Management (ASD) • Once Sx present (includes paradoxical emboli)  surgical/catheter closure. • If no Sx surgical/catheter closure recommended if *Qp:Qs is > 1.5:1, or if PAH present. • Transcatheter closure devices (double umbrella) applicable to patients with smaller defect. *Qp:Qs- pulmonary to systemic blood flow

29. Surgical Management (ASD) • Direct suture closure or pericardial patch. • If present, partial anomalous pulmonary veins are re-routed to the left atrium. • Surgical risk is very low (<1% mortality). Closure is highly recommended in pre-school or pre-adolescent years.

30. Pulmonic Stenosis • Pathology: “Dome shaped” stenosis of the PV most common form. RV develops concentric hypertrophy and reflects degree of obstruction at the valvular level. • Can be associated with other congenital defects such as VSD (see Tetralogy of Fallot, below).

31. Pulmonic Stenosis Images.google.com

32. Abnormal Physiology (PS) • PV area must be reduced by 60% or more to be hemodynamically significant. • Peak systolic gradient > 40mmHg - moderate PS • Peak systolic gradient > 75mmHg -severe PS • Major hemodynamic burden is Rt ventricular pressure overload. Expected ECG finding? • RV failure occurs with severe obstruction, resulting in decreased CO and related Sx and signs.

33. Clinical Manifestations (PS) • Occurs 10% all congenital lesions; most infants and children asymptomatic unless obstruction is severe- DOE, fatigue. • Physical exam: • Systolic thrill-suprasternal notch; prominent RV impulse upper LSB. • Early systolic clickupper LSB. • Murmur is loud (Gr 3-4), harsh, crescendo-decrescendo at upper LSB radiating towards clavical and louder with inspiration. Duration of murmur correlates with severity of obstruction.

34. Investigative Findings (PS) • CxR-usually normal • ECG- Mild - normal; severe- RVH • Echo/Doppler - Identifies obstruction; estimates severity of PS. • Cath- usually not needed to make diagnosis but performed for treatment purposes: • Baloon valvuloplasty opens stenotic valve.

35. Natural History/Prognosis • Mild to moderate stenosis - well tolerated; frequent follow up and echo/doppler necessary as progressive PS may develop over time. • Severe stenosis - poor prognosis without intervention; RV failure develops with premature death in adults.

36. Management of PS • Infants with severe PS - valvuloplasty. • In children and adults timing of valvuloplasty dependent on gradient:No intervention for gradient < 25mm.Valvuloplasty always indicated for gradient >75mm. • Ballon valvuloplasty has replaced surgery as a first approach.

37. PS: Balloon Valvuloplasty

38. Patent Ductus Arteriosus Images.google.com

39. Patent Ductus Arteriosus (PDA) • Persistent patency of the vessel that normally connects the pulmonary arterial system and the aorta in the fetus. • PDA normally closes within 2-3 days after birth. It runs from the origin of the LPA to the lower aortic arch just beyond the left subclavian artery. • Ductus often remains open in pre-term deliveries. • Important to differentiate from post-term PDA

40. Abnormal Physiology (PDA) • Small ductus- high resistance to flow; well tolerated; small left to right shunt. • Moderate ductus- elevated PAP, significant shunting. • Large ductus- Ao and PA in free communication; equal pressures with marked left to right shunting, pulmonary congestion, LV dysfunction and failure, and development of PVOD.

41. Clinical Manifestations (PDA) • History- maternal exposure to rubella; premature deliveries. • Symptoms –variable; with large shunt, HF develops in first weeks of life. • PE - Systolic thrill over PA in suprasternal notch and LSB; apical and RV impulse increased.Murmur is a continuous (through systole and diastole) “machinery murmur” Gr IV or louder at LSB (3rd and 4th ICS) and below clavicle-peaks near S2.

42. Additional Findings • Dependent on size of ductus/degree of shunting: • CxR- increased LA, LV, pulmonary vascularity (shunt vascularity). • ECG: LAE/LAA* and LVH. • Echo-doppler - LAE, LVE and LVH; shunt may be visualized by 2D echo/doppler. • Cardiac MRI and CT also useful in identifying PDA *LAA- left atrial abnormality

43. Natural History/Management • Complications include endocarditis, HF, PAH, PVOD, and sudden death. • Ultimate goal - closure of the ductus.In premature infants treatment with Indomethacin is 1st line therapyconstriction of ductus. • Surgical or catheter closure are safe and effective when ductus remains open.

44. Coarctation of the Aorta • 8-9 % of all infants presenting with CHD. • Discreet narrowing of the distal segment of the aortic arch, just distal to the origin of the subclavian artery. • Coarctation causes obstruction to outflow to the lower half of the body. Principle cardiovascular abnormalities: • LVH due to pressure overload • Arterial hypertension

45. Coarctation of the Aorta Allreferhealth.com Images.google.com

46. Abnormal Physiology (Coarct) • Systolic and diastolic pressures above the coarctation are elevated; below reduced. • A secondary form of HTN • Prominent collateral circulation to the lower body develops via the internal mammary and subcostal arteries (rib notching on CxR).

47. Clinical Manifestations • 50% present as infants with HF. Concomitant VSD often present. • In older children Sx include fatigue, dyspnea and claudication in legs while running. • Hypertension in childhood is a red flag for secondary hypertension. • Consider also: Renal artery stenosis

48. Clinical Manifestations • PE: In older children and adults- differential blood pressure between arms and legs; a measured difference > 10mmHg systolic is diagnostic. • Majority of patients will develop marked HTN to upper part of body -high renin HTN due to decreased perfusion of kidneys. • Upper body well developed; legs very thin.

49. Additional Findings • CxR: LV prominent; HF-infants; notching of inferior margins of ribs in adolesence. • ECG: LVH. • Echo-doppler: Suprasternal imaging may show the coarct; LVH, LV dysfunction. • Cardiac MRI and CT also useful for coarctation • Cardiac cath: Pressure differential across the coarct with angiographic visualization and any associated lesions defined.

50. Natural Hx and Progression • 50% of infants will present with HF and respond well to medical treatment. • Hypertension develops with age and often persists if surgical correction is performed after age 6. Significant coarcts, if uncorrected, result in premature death, often by age 50. • Surgery: Direct resection/repair if possible; adequate collaterals crucial for safe repair- if absent, lower body paralysis can occur due to interrupted blood flow to spinal cord during surgery. Stenting via catheters is being investigated/used as an option.