ACYANOTIC DISEASE- Non cyanotic heart diseases
- 1. PRESENTER: MISHECK NKOWANI 7TH YEAR MODERATOR : DR FISEKO ACYANOTIC DISEASE CONGENITAL HEART DISEASE
- 2. CHD occur during the 1st 8 wks. of fetal development Most congenital defects are well tolerated during fetal life. Incidence • 8/1000 live births • 3-4/100 still born • 2/100 premature infants excluding PDA These are the most common birth defects ETIOLOGY Generally considered to be caused by factors that 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. Such as maternal risk factors • seizure disorders or intake of anti-seizure medications • intake of lithium for depression • Lupus
- 3. 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 Family History: • risk increases when either parent has CHD, or when another sibling was born with 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 increase 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.
- 5. VENTRICULAR SEPTAL DEFECT Etiology and Epidemiology The ventricular septum is a complex structure that can be divided into four components. The largest component is the muscular septum. The inlet or posterior septum comprises endocardial cushion tissue. The subarterial or supracristal septum comprises conotruncal tissue. The membranous septum is below the aortic valve and is relatively small. VSDs occur when any of these components fails to develop normally VSD, the most common congenital heart defect, accounts for 25% of all congenital heart disease. Perimembranous VSDs are the most common of all VSDs (67%). Although the location of the VSD is important prognostically and in approach to repair, the amount of flow crossing a VSD depends on the size of the defect and the pulmonary vascular resistance. Large VSDs are not symptomatic at birth because the pulmonary vascular resistance is normally elevated at this time. As the pulmonary vascular resistance decreases over the first 6 to 8 weeks of life, the amount of shunt increases, and symptoms may develop. Clinical Manifestations Small VSDs with little shunt are often asymptomatic but have a loud murmur. Moderate to large VSDs result in pulmonary
- 7. overcirculation and heart failure. The typical physical finding with a VSD is a pansystolic murmur, usually heard best at the lower left sternal border. There may be a thrill. Large shunts increase flow across the mitral valve causing a mid-diastolic murmur at the apex. The splitting of S2 and intensity of P2 depend on the pulmonary artery pressure . Imaging Studies Electrocardiogram (ECG) and chest x-ray findings depend on the size of the VSD. Small VSDs usually have normal studies. Larger VSDs cause volume overload to the left side of the heart, resulting in ECG findings of left atrial and ventricular enlargement and hypertrophy. A chest x-ray may reveal cardiomegaly, enlargement of the left ventricle, an increase in the pulmonary artery silhouette, and increased pulmonary blood flow. Pulmonary hypertension due to either increased flow or increased pulmonary vascular resistance may lead to right ventricular enlargement and hypertrophy. Treatment Approximately one third of all VSDs close spontaneously. Small VSDs usually close spontaneously and, if they do not require surgery • Prophylactic antibiotics to prevent bacterial endocarditis • Surgical repair – VSD will be closed with stitches or special patch
- 8. ATRIAL SEPTAL DEFECT Etiology and Epidemiology During the embryologic development of the heart, a septum grows toward the endocardial cushions to divide the atria. Failure of septal growth or excessive reabsorption of tissue leads to ASDs. ASDs represent approximately 10% of all congenital heart defects. A secundum defect, with the hole in the region of the foramen ovale, is the most common ASD. A primum ASD, located near the endocardial cushions, may be part of a complete atrioventricular canal defect or may be present with an intact ventricular septum. The least common ASD is the sinus venosus defect, which may be associated with anomalous pulmonary venous return. Clinical Manifestations The pathophysiology and amount of shunting depend on the size of the defect and the relative compliance of the both ventricles. Even with large ASDs and significant shunts, infants and children are rarely symptomatic. A prominent right ventricular impulse at the left lower sternal border (LLSB) often can be palpated. A soft (grade I or II) systolic ejection murmur in the region of the right ventricular outflow tract and a fixed split S2 (due to overload of the right ventricle with prolonged ejection into the pulmonary circuit) are often audible. A larger shunt may result in a mid- diastolic murmur at the LLSB as a result of the increased volume passing across the tricuspid valve.
- 10. SIGNS AND SYMPTOMS • infant tires easily when feeding • fatigue • sweating • tachypnea, tachycardia • shortness of breath, crackles • poor growth • murmur
- 11. Imaging Studies ECG and chest x-ray findings reflect the increased blood flow through the right atrium, right ventricle, pulmonary arteries, and lungs. The ECG may show right axis deviation and right ventricular enlargement. A chest radiograph may show cardiomegaly, right atrial enlargement, and a prominent pulmonary artery. Treatment Medical management is rarely indicated. If a significant shunt is still present at around 3 years of age, closure is usually recommended. Many secundum ASDs can be closed with an ASD closure device in the catheterization laboratory. Primum and sinus venosus defects require surgical closure
- 12. PATENT DUCTUS ARTERIOSUS Etiology and Epidemiology The ductus arteriosus allows blood to flow from the pulmonary artery to the aorta during fetal life. Failure of the normal closure of this vessel results in a PDA With a falling pulmonary vascular resistance after birth, left-to-right shunting of blood and increased pulmonary blood flow occur. Excluding premature infants, PDAs represent approximately 5% to 10% of congenital heart disease. Clinical Manifestations Symptoms depend on the amount of pulmonary blood flow. The magnitude of the shunt depends on the size of the PDA (diameter, length, and tortuosity) and the pulmonary vascular resistance. Small PDAs are asymptomatic; moderate to large shunts can produce the symptoms of heart failure as the pulmonary vascular resistance decreases. The physical examination findings depend on the size of the shunt. A widened pulse pressure is often present as a result of the runoff of blood into the pulmonary circulation during diastole. A continuous, machine-like murmur can be heard at the left infraclavicular area, radiating along the pulmonary arteries and often well heard over the left side of the back. Larger shunts with increased flow across the mitral valve mayresult in a mid-diastolic murmur at the apex and a hyperdynamic precordium. Splitting of S2 and intensity of P2 depend on the pulmonary artery pressure A thrill may be palpable.
- 13. . Imaging Studies ECG and chest x-ray findings are normal with small PDAs. Moderate to large shunts may result in a full pulmonary artery silhouette and increased pulmonary vascularity. ECG findings vary from normal to evidence of left ventricular hypertrophy. If pulmonary hypertension is present, there is also right ventricular hypertrophy. Treatment Spontaneous closure of a PDA after a few weeks of age is uncommon in full-term infants. Moderate and large PDAs may be managed initially with diuretics, but eventually require closure. Elective closure of small, hemodynamically insignificant PDAs is controversial. Most PDAs can be closed in the catheterization laboratory by either coil embolization or a PDA closure device
- 14. ENDOCARDIAL CUSHION DEFECT Etiology and Epidemiology Endocardial cushion defects, also referred to as atrioventricular canal defects, may be complete or partial Failure of the septum to fuse with the endocardial cushion results in abnormal atrioventricular valves as well. The complete defect results in a primum ASD, a posterior or inlet VSD, and clefts in the anterior leaflet of the mitral and septal leaflet of the tricuspid valves. In addition to left-to- right shunting at both levels, there may be atrioventricular valve insufficiency. Clinical Manifestations The symptoms of heart failure usually develop as the pulmonary vascular resistance decreases over the first 6 to 8 weeks of life. Symptoms may be earlier and more severe with significant
- 15. atrioventricular valve insufficiency. Pulmonary hypertension resulting from increased pulmonary circulation often develops early. The presence of murmurs varies depending on the amount of shunting at both atrial and ventricular levels. If there is a large VSD component, S2 will be single. Growth is usually poor. Complete endocardial cushion defects are most commonly seen in children with Down syndrome. Imaging Tests The diagnosis usually is made with echocardiography. A chest radiograph reveals cardiomegaly with enlargement of all chambers and the presence of increased vascularity. An ECG reveals left axis deviation and combined ventricular hypertrophy and may show combined atrial enlargement. Treatment Initial management includes diuretics such as and afterload reduction for treatment of heart failure. Surgical repair of the defect ultimately is required
- 16. PULMONARY STENOSIS Etiology Pulmonary stenosis accounts for approximately 10% of all congenital heart disease and can be valvular, subvalvular, or supravalvular in nature. Pulmonary stenosis results from the failure of the development, in early gestation, of the three leaflets of the valve, insufficient resorption of infundibular tissue, or insufficient canalization of the peripheral pulmonary arteries. Clinical Manifestations Symptoms depend on the degree of obstruction present. Mild pulmonary stenosis is asymptomatic. Moderate to severe stenosis results in exertional dyspnea and easy fatigability. Newborns with severe stenosis may be more symptomatic and even cyanotic because of right-to-left shunting at the atrial level. Pulmonary stenosis causes a systolic ejection murmur at the second left intercostal space which radiates to the back. A thrill may be present. S2 may be widely split with a quiet pulmonary component. With more severe pulmonary stenosis, an impulse at the lower left sternal border results from right ventricular hypertrophy. Valvular stenosis may result in a click that varies with respiration. Worsening stenosis causes an increase in the duration of the murmur and a higher frequency of the sound. The systolic ejection murmurs of peripheral pulmonary stenosis are heard distal to the site of obstruction in the pulmonary circulation, including radiation to the back
- 17. Imaging Tests ECG and chest x-ray findings are normal in mild stenosis. Moderate to severe stenosis results in right axis deviation and right ventricular hypertrophy. The heart size is usually normal on chest x-ray, although dilation of the main pulmonary artery may be seen. Echocardiography provides assessment of the site of stenosis, degree of hypertrophy, and valve morphology, as well as an estimate of the pressure gradient Treatment Valvular pulmonary stenosis usually does not progress, especially if it is mild. Balloon valvuloplasty is usually successful in reducing the gradient to acceptable levels for more significant or symptomatic stenosis. Surgical repair is required if balloon valvuloplasty is unsuccessful or when subvalvular (muscular) stenosis is present
- 18. 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 COARCTATION OF THE AORTA
- 19. Imaging Studies The ECG and chest x-ray show evidence of right ventricular enlargement and hypertrophy in infantile coarctation with marked cardiomegaly and pulmonary edema. Echocardiography shows the site of coarctation and associated lesions. In older children, the ECG and chest x-ray usually show left ventricular hypertrophy and a mildly enlarged heart. Rib notching may also be seen in older children (>8 years of age) with large collaterals. Echocardiography shows the site and degree of coarctation, presence of left ventricular hypertrophy, and aortic valve morphology and function. Treatment Management of an infant presenting with cardiac decompensation includes intravenous infusion of prostaglandin E1 (chemically opens the ductus arteriosus), • inotropic agents, • diuretics, • supportive care. Balloon angioplasty has been done, especially in critically ill infants, but surgical repair of the coarctation is most commonly performed. Ballooning and stenting of older patients with coarctation has become more accepted as primary therapy, but surgical repair remains a common form of management