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Alterations of Cardiovascular Function in Children. Chapter 24. Congenital Heart Defects. Major cause of death in the first year of life other than prematurity Prenatal, environmental, and genetic risk factors Maternal rubella, type 1 diabetes, alcoholism, PKU, and hypercalcemia Drugs
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Alterations of Cardiovascular Function in Children Chapter 24
Congenital Heart Defects • Major cause of death in the first year of life other than prematurity • Prenatal, environmental, and genetic risk factors • Maternal rubella, type 1 diabetes, alcoholism, PKU, and hypercalcemia • Drugs • Chromosome aberrations
Congenital Heart Disease • Heart defects • Hemodynamic alterations • Right-to-left shunt, left-to-right shunt • Status of tissue oxygenation • Cyanotic defects • Acyanotic defects
Obstructive Defects • Coarctation of the aorta • Narrowing of the lumen of the aorta that impedes blood flow • Coarctation of the aorta is almost always in a juxtaductal position, but it can occur anywhere between the origin of the aortic arch and the bifurcation of the aorta in the lower abdomen
Obstructive Defects • Aortic stenosis • Narrowing of the aortic outflow tract • Caused by malformation or fusion of the cusps • Causes an increased workload on the left ventricle
Obstructive Defects • Valvular aortic stenosis • Malformed or fused cusps • Progressive obstruction with episodes of ischemia • Strenuous activity limited • Subvalvular aortic stenosis • Stricture caused by a fibrous ring below a valve • Konno procedure used to correct
Obstructive Defects • Pulmonic stenosis • Narrowing of the pulmonary outflow tract • Abnormal thickening of the valve leaflets • Narrowing of the valve • Pulmonary semilunar valve atresia
Defects Increasing Pulmonary Blood Flow • Patent ductus arteriosus (PDA) • Failure of the ductus arteriosus to close • PDA allows blood to shunt from the pulmonary artery to the aorta
Defects Increasing Pulmonary Blood Flow • Atrial septal defect • Abnormal opening between the atria • Three major types • Ostium primum defect • Ostium secundum defect • Sinus venosus defect
Defects Increasing Pulmonary Blood Flow • Ventricular septal defect (VSD) • Abnormal communication between the ventricles • Most common type of congenital heart lesion • Types • Perimembranous VSD • Muscular VSD • Eisenmenger syndrome
Defects Increasing Pulmonary Blood Flow • Atrioventricular canal defect (AVC) • Results from nonfusion of the endocardial cushions • Demonstrates abnormalities in the atrial and ventricular septa and atrioventricular valves • Complete, partial, and transitional AVCs
Defects Decreasing Pulmonary Blood Flow • Tetralogy of Fallot • Syndrome represented by four defects • Ventricular septal defect (VSD) • Overriding aorta • Pulmonary valve stenosis • Right ventricle hypertrophy
Defects Decreasing Pulmonary Blood Flow • Tricuspid atresia • Imperforate tricuspid valve • Lack of communication between the right atrium and right ventricle • Additional defects • Septal defect • Hypoplastic or absent right ventricle • Enlarged mitral valve and left ventricle • Pulmonic stenosis
Mixed Defects • Transposition of the great arteries • Aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle
Mixed Defects • Transposition of the great arteries • Results in two separate, parallel circuits • Unoxygenated blood circulates continuously through the systemic circulation • Oxygenated blood circulates continuously through the pulmonary circulation • Extrauterine survival requires communication between the two circuits
Mixed Defects • Total anomalous pulmonary venous connection (TAPVC) • Pulmonary veins connect to the right side of the heart, directly or indirectly through one or more systemic veins that drain into the right atrium • Classified by point of attachment • Supracardiac • Cardiac • Infracardiac
Mixed Defects • Truncus arteriosus • Failure of the embryonic artery and the truncus arteriosus to divide into the pulmonary artery and the aorta • The trunk straddles an always present VSD • Types I, II, and III
Obstructive Defects • Hypoplastic left heart syndrome • Abnormal development of the left-sided cardiac structures • Obstruction to blood flow from the left ventricular outflow tract • Under development of the left ventricle, aorta and aortic arch, and mitral atresia or stenosis
Congestive Heart Failure • Heart is not able to maintain cardiac output at level that meets demands of body • Result from poor ventricular function
Acquired Cardiovascular Disorders • Kawasaki disease • Also known as mucocutaneous lymph node syndrome • Acute, self-limiting systemic vasculitis that may result in cardiac sequelae
Kawasaki Disease • Stages • Acute: capillaries, venules, arterioles, and the heart become inflamed • Subacute: inflammation of larger vessels; coronary aneurysms appear • Convalescent: medium-sized arteries begin granulation process; small vessel inflammation decreases
Kawasaki Disease • Stages • Post convalescent: scarring of vessels, thickening of tunica intima, calcification, coronary artery stenosis
Kawasaki Disease • Diagnosis (5 of 6 major findings) • Fever for 5 or more days (unresponsive to antibiotics) • Bilateral conjunctivitis without exudation • Erythema of oral mucosa (strawberry tongue)
Kawasaki Disease • Diagnosis (5 of 6 major findings) • Changes in the extremities, such as peripheral edema and erythema with desquamation of palms and soles • Polymorphous rash • Cervical lymphadenopathy
Acquired Cardiovascular Disorders • Systemic hypertension • Hypertension in children differs from adult hypertension • Often have an underlying disease • Renal disease or coarctation of the aorta • A cause of the hypertension in children is almost always found • Children with hypertension are commonly asymptomatic
Acquired Cardiovascular Disorders • Childhood obesity • Multivariable and multidimensional • Risk factors • Obesity, insulin resistance, diabetes, cardiovascular disease • Childhood nutrition, level of physical activity, and engagement of sedentary activities (TV, computer use, etc.) • Association with parental obesity