Congenital Heart Disease (CHD)

1. Congenital Heart Disease (CHD) By Alireza Pourtalebi

2. Blood circulation after birth: The transformation from fetal to neonatal circulation involves two major changes: 1. A marked increase in systemic resistance. caused by loss of the low-resistance placenta. 2. A marked decrease in pulmonary resistance. caused by pulmonary artery dilation with the neonate’s first breaths.

3. Fetal Circulation 8 Hours old 24-72 hrs

4. Blood circulation after birth: • With the first breaths of air the baby takes at birth, the fetal circulation changes. A larger amount of blood is sent to the lungs to pick up oxygen. • Because the ductus arteriosus(the normal connection between the aorta and the pulmonary valve) is no longer needed, it begins to wither and close off. (72 hrs.) • The circulation in the lungs increases and more blood flows into the left atrium of the heart  pressure causes the foramen ovale to close and blood circulates normally

5. Epidemiology of CHD Incidence - 8/1000 live births - 3-4/100 still born - 2/100 premature infants excluding PDA -10-25/100 abortuses Most congenital defects are well tolerated during fetal life. Etiology - Unknown in most cases - Genetic factors - single gene defect - Chromosomal abnormality - Environmental factors - Gender differences in type of CHD - occur during the 1st 8 wks. of fetal development

6. Factors Contributing to CHD 85 to 90 % of cases, there is no identifiable cause for the heart defect  generally considered to be caused by multifactorial inheritance. factors are usually both genetic and environmental, where a combination of genes from both parents, in addition to unknown environmental factors, produce the trait or condition. Maternal Factors: seizure disorders w/ intake of anti-seizure medications intake of lithium for depression uncontrolled IDDM lupus german measles (rubella) – 1st trimester of pregnancy

7. Factors Contributing to CHD Family History: risk increases when either parent has CHD, or when another sibling was born w/ CHD If you have had one child with CHD, the chance that another child will be born with CHD ranges from 1.5 to 5 %, depending on the type of CHD in the first child. If you have had two children with CHD, then the risk  to 5 to 10 %, to have another child with CHD. If the mother has CHD, the risk for a child to be born with CHD ranges from 2.5 to 18 percent, with an average risk of 6.7 percent. Chromosome abnormalities: 5 to 8 % of all babies with CHD have a chromosome abnormality includes Down syndrome, trisomy 18 and trisomy 13, Turner’s syndrome, Cri-du-chat syndrome

8. Relative Frequency of Congenital Heart Lesions

9. Relative Frequency

10. Clues for Evaluation of an Infant with suspected CHD 1. On History and Physical Examination color) Acyanotic Cyanotic 2. Chest roentgenogram Normal Increased/Plethora pulmonary blood flow Decreased/Oligemia 3. Electrocardiogram - Right - Left hypertrophy - Biventricular Final diagnosis - Precordial examinant - Echocardiography

11. Acyanotic Congenital Heart Diseases 1. Left to Right Shunt Lesions Pink Baby (L  R shunt) L  R shunts cause CHF and pulmonary hypertension. This leads to RV enlargement, RV failure These babies present with CHF and respiratory distress. 1.1. Atrial Septal Defect  Defect occur in any portion of the atrium - Ostiumsecundum (at fossa ovalis) - Ostiumprimum (ECD) (lower atrial septum) - Sinus venosus (upper atrial septum) Pathophysiology  Left to right shunt - Transatrial in OS & SV - Transatrial & transventricular in OP

13. Acyanotic CHD Clinical Manifestations  Most are asymptomatic  Right ventricular lift  Wide & fixed split of 2nd heart sound  Systolic ejection murmur  Mid-diastolic murmur at tricuspid area  Holosystolic murmur at mitral area in OP

14. Acyanotic CHD Diagnosis  Clinical  CXR - Right. V & A enlargement - Large pulm. artery - ↑edpulm. vascularity  ECG - volume overload, - right axis deviation - minor right ventricular conduction delay  Echocardiography  Catheterization Prognosis - Well tolerated Complications - pulm. Hypertension, Eismenger syndrome Treatment  Surgery - For all symptomatic ASD - Asymptomatic patients with shunt ratio>2:1

18. 1.2 Ventricular Septal Defect An opening in the ventricular septum allows oxygenated blood to pass from the left ventricle, through the opening in the septum, and then mix with unoxygenated blood in the right ventricle. VSDs are the most commonly occurring type of congenital heart defect, occurring in 14-17 % of babies born each year. occur when the partitioning process does not occur completely, leaving an opening in the ventricular septum.  The most common cardiac malformation  Defect occur in any portion of the septum - Majority membranous - Muscular – Single or Swiss-cheese defect Pathophysiology Lt to Rt shunt  Restrictive if defect is small (0.5cm2)  Non-restrictive - large defect (> 1cm2) - Right and left vent. Pressure equalized EFFECTS: When blood passes through the VSD from the left ventricle to the right ventricle  a larger volume of blood than normal must be handled by the right side of the heart  extra blood then passes through the pulmonary artery into the lungs  pulmonary hypertension and pulmonary congestion  pulmonary arteries become thickened and obstructeddue to increased pressure If VSD is not repaired, and lung disease begins to occur  pressure in the right side of the heart will eventually exceed pressure in the left  R to L shunt  cyanosis Due to high pressure --- tissue damage may eventually occur in the right ventricle  bacteria in the bloodstream can easily infect this injured area  bacterial endocarditis.

20. Signs and Symptoms • fatigue • sweating • tachypnea • murmur • heavy breathing • congested breathing • disinterest in feeding, or tiring while feeding • poor weight gain • The larger the opening, the greater the amount of blood that passes through and overloads the right ventricle and lungs. Diagnosis - Clinical - CXR - Cardiomegaly - Plethoric lung - ECG - Echocardiography Prognosis - 30-50% small defects close by 2 yr of age - Rarely moderate to large defects close

21. Treatment Medical management - digoxin - diuretics Adequate nutrition - high-calorie formula or breast milk - supplemental tube feedings Prophylactic antibiotics to prevent bacterial endocarditis Surgical repair – VSD will be closed w/ stitches or special patch Interventional cardiac catheterization – Septal occluder Complications - Infective endocarditis - Recurrent lung infection - Heart failure - Pulmonary HTN - Acquired pulmonary stenosis -- aortic valve regurgitation

23. Patent Ductus Arteriosus (PDA) • In many children, there is no known reason for the ductusarteriosus remaining open. However, PDA is seen more often in the following: • premature infants • infants born to a mother who had rubella during the first trimester of pregnancy EFFECTS: PDA  oxygenated blood passes from the aorta to the pulmonary artery & mixes w/ the unoxygenated blood w/c goes to the lungs   blood volume to the lungs  pulmonary hypertension & congestion Further, because blood is pumped at high pressure through the PDA, the lining of the pulmonary artery will become irritated and inflamed. Bacteria in the bloodstream can easily infect this injured area  bacterial endocarditis.  Functional closure soon after birth  Aortic end of the ductus distal to the origin of left subclavian artery and the other end at bifurcation of pulmonary artery. • Male to female ratio 1:2 Pathology Deficiency of mucoid endothelial layer & muscular media in term infant. Lt to Rt shunt - size- ratio of pulm. to systemic resistance Reversal of shunt

24. Signs and Symptoms • fatigue • sweating • tachypnea • shortness of breath • congested breathing • disinterest in feeding, or tiring while feeding • poor weight gain • murmur • increase systolic BP • bounding pulse Diagnosis - Clinical - Chest X-ray - ECG - Echocardiography Prognosis - Small PDA - normal life - Large PDA - CHF Complications - Infective Endocarditis/Endarteritis - CHF - Embolization - Pulmonary HTN Treatment - Medical - Surgical closure

25. Medical Management Indomethacin IV (prostaglandin inhibitor) may help close a PDA. - works by stimulating the muscles inside the PDA to constrict, thereby closing the connection Digoxin Diuretics adequate nutrition (premature infants or those infants with a large PDA may become tired when feeding, and are not able to eat enough to gain weight) high-calorie formula or breast milkSpecial nutritional supplements may be added to formula or pumped breast milk that increase the number of calories in each ounce, thereby allowing your baby to drink less and still consume enough calories to grow properly. • supplemental tube feedings- infants who can drink part of their bottle, but not all, may be fed the remainder through the feeding tube • - infants who are too tired to bottle-feed may receive their formula or breast milk through the feeding tube alone. • PDA surgical repair or closure- Repair is usually indicated in infants younger than 6 months of age who have large defects that are causing symptoms, such as poor weight gain and rapid breathing- Transcatheter coil closure of the PDA- PDA ligation • - involves closing the open PDA with stitches or the vessel connecting the aorta and pulmonary artery may be cut and cauterized

27. 2. Obstructive Lesions 2.1. Pulmonic Stenosis - 4 types - Valvular - Infundibular - Supra valvular - Peripheral Pathophysiology - Rt outlet obstruction → Pressure work ↓ Rt vent. hyperthropy Clinical Manifestation - Mild to moderate - asymptomatic - Critical stenosis - Systolic ejection murmur - Heart failure in neonates & infants - Rarely cyanosis Diagnosis - Clinical - CXR - Rt vent. hypertrophy - reduced pulm. blood flow - ECG - Echocardiography Prognosis- good in mild to moderate Complications- CHF in severe Ps - rarely IE Treatment- vavular PS - ballon valvoplasty - surgery

29. 2.2 Aortic Stenosis -Valvular - the commonest -Supra valvular -Subvalvular (subaortic) Clinical Manifestation  Mild stenosis - Normal pulse & apical impulse - Systolic ejection M - Normal to enlarged heart size  Critical stenosis - Left ventricular failure - pulm. edema, cardiomegaly - Weak peripheral pulses - Weak systolic M - Paradoxical split 2nd heart sound Diagnosis - Clinical - CXR - ECG - Echocardiography - Graded exercise testing Prognosisis good for mild to moderate Treatment - Balloon valvoplasty - Surgical

33. Coarctation of the Aorta • Narrowing of the aorta • can occur anywhere, but is most likely to happen in the segment just after the aortic arch. This narrowing restricts the amount of blood to the lower part of the body • occurs in about 8-11 % of all children with CHD EFFECTS: • The left ventricle has to work harder to try to move blood through the narrowing in the aorta  left-sided heart failure • BP is higher above the narrowing, and lower below the narrowing. Older children may have headaches from too much pressure in the vessels in the head, or cramps in the legs or abdomen from too little blood flow in that region. • The walls of the arteries may become weakened by high pressure  spontaneous tears  cause a stroke or uncontrollable bleeding. •  risk for bacterial endocarditis. • -Occur at any site from the arch of aorta to iliac bifurcation • -98% juxta ductal Pathogenesis • In utero arch hypoplasia Rt heart output passes through the ductus

36. Signs and Symptoms • irritability • pale skin • sweating • heavy and/or rapid breathing • poor feeding • poor weight gain • cold feet and/or legs • diminished or absent pulses in the feet • BP in the arms significantly greater than the BP in the legs • Mild narrowing may not cause symptoms at all. Often, a school-aged child or adolescent is simply noted to have high BP or a heart murmur on a physical examination. Some may complain of headaches or cramps in the lower sections of the body. Clinical Manifestation  Hypertension → mechanical obstruction→ renal  Differential cyanosis → pink upper extr. → cyanosed lower extr.  Classic signs - Disparity in pulse & BP - Radio-femoral delay - Systolic M at LMSB & inter-scapular area

37. Diagnosis - Clinical - CXR - cardiomegaly & pulm. congestion - Notching of ribs - ECG - Echocardiography Prognosis– Untreated cases succumb by 20-40 years Complications - CVA - I/E - Aneurysms Treatment - Medical - IV PGE1 in neonatal age - Surgery • interventional cardiac catheterization- During the procedure, the child is sedated and a small, thin, flexible tube (catheter) is inserted into a blood vessel in the groin and guided to the inside of the heart • - once the catheter is in the heart, the cardiologist will pass an inflated balloon through the narrowed section of the aorta to stretch the area open. • - A small device, called a stent, may also be placed in the narrowed area after the balloon dilation to keep the aorta open. • surgical repairYour child's coarctation of the aorta may be repaired surgically in an operating room. The surgical repair is performed under GA. The narrowed area is either surgically removed, or made larger with the help of surrounding structures or a patch.

38. 3. Pulmonary Vascular Disease (Eismenger syndrome) - Occur in shunt lesions VSD - mainly ASD PDA - Reversal of shunt due to pulm. HTN→ Cyanosis 4. Regurgitant Lessons - Pulmonary valvular insufficiency - Congenital mitral valve insufficiency - Mitral valve prolapse

39. Cyanotic Congenital Heart Disease 1. Cyanotic lesions with decreased pulmonary blood flow 1.1. Tetralogy of Fallot Consists: 1. Rt ventricular outflow obst. 2. Ventricular septal defect 3. Dextroposition of the aorta 4. Right ventricular hypertrophy EFFECTS: If the right ventricle obstruction is severe, or if the pressure in the lungs is high  a large amount of oxygen-poor (blue) blood passes through the VSD, mixes with the oxygen-rich (red) blood in the left ventricle, and is pumped to the body  cyanosis The more blood that goes through the VSD, the less blood that goes through the pulmonary artery to the lungs  oxygenated blood to the left side of the heart. Soon, nearly all the blood in the left ventricle is oxygen-poor (blue). This is an emergency situation, as the body will not have enough oxygen to meet its needs.

40. Signs and Symptoms • Cyanosis (blue color of the skin, lips, and nail beds) that occurs with such activity as crying or feeding • Some babies do not have noticeable cyanosis, but may instead be very irritable or lethargic due to a decreasing amount of oxygen available in the bloodstream. • Murmur • Tachycardia • Irritability • Syncope • Clubbing of fingers Pathophysiology - Outflow obstruction - Hypertrophy of subpulmonicmuslce - Normal or small pulmonary valve annulus - Rarely pulmonary atresia - VSD - Non-restrictive, located just below aortic valve - Aortic arch is right side in 20% - Right ventricular output shunts to the aorta

41. Clinical Manifestation - Rarely pink TOF - in the absence of obstruction - Cyanosis - Clubbing - Squatting position in walking children - Paroxysmal hypercyanotic attacks  occur during 1st 2 years - Systolic ejection M - Delayed growth & development - Single 2nd heart sound Diagnosis - CXR - Narrow base & uplifted apex - A boot or wooden shoe - decreased pulm. vascularity - Right side aortic arch in 20% - ECG - Echocardiography Complication - Cerebral thrombosis - in < 2 years - Brain abscess - Infective endocarditis - Polycythemia - CHF in pink TOF

43. Treatment Severe outflow obstruction - Medical Px - PGE1 infusion - Prevent dehydration - Partial exchange transfusion - Oral propranolol for tet spells - Surgery - Blalock Taussig - Total correction

46. 1.2. Pulmonary Atresia - With VSD - Extreme form of TOF - Without VSD - No egress of blood from Rt vent. - Shunt through foramen ovale to Lt atrium Left ventricle systemic circulation Aorta pulmonic circulation - Hypoplastic right ventricle (PDA) Clinical Manifestation - Cyanosis at birth - Respiratory distress - Single 2nd heart sound - No murmur Diagnosis - CXR - ECG - Echocardiography Treatment - PGE1 - Surgery

48. Tricuspid Atresia • In this condition, there is no tricuspid valve, therefore, no blood flows from the right atrium to the right ventricle. • Blood in right atrium  foramen ovale  left atrium and left ventricle  aorta • Tricuspid atresia defect is characterized by the following: • a small right ventricle • a large left ventricle • Small VSD and PDA • diminished pulmonary circulation • cyanosis - bluish color of the skin and mucous membranes caused from a lack of oxygen. • A surgical shunting procedure is often necessary to increase the blood flow to the lungs. Clinical Manifestation - Cyanosis at birth - Polycythemia - Easily fatiguability - Exertional dyspnea Diagnosis - EXR -Pulm. Under circulation - ECG -Lt axis deviation & Lt vent. hypertrophy - Echocardiography Treatment - PGE1 - Surgery - Aortico - pulmonary Shunt - Bidirectional Glenn shunt - Modified Fontan operation

50. 1.4. Ebstein Anomaly of the tricuspid valve - Down ward displacement of the tricuspid valve - Right ventricle with two parts - atrialized - normal ventricular myocardium - Abnormal tricuspid valve - Huge Rt atrium - Tricuspid regurgitation - Compromised Rt ventricular function Clinical Manifestations - Easly fatiguability - Cyanosis - Dysrhythmia - Rt to Lt shunt through formen ovale - Holosystolic M at tricuspid area - Heart failure Diagnosis - CXR - box shaped heart - ECG - Right BBB - Superior axis deviation Treatment - PGE1 - Surgery