Cơ bắp kém phát triển LV XẢY RA trong 1,3-3,8% của trẻ sơ sinh với bệnh tim bẩm sinh tím tái nhẹ khi sinh; tối thiểu auscultatory phát hiện, nhanh chóng khởi đầu của suy tim đã để lại sâu sắc còn ống động mạch đóng cửa ở 3-5 ngày tuổi-bất thường Associated hẹp hai lá, hẹp động mạch chủ | Chapter 2 Cardiovascular Disorders 31 Hypoplastic Left Heart Syndrome Essentials of Diagnosis Underdeveloped LV musculature occurs in of infants with congenital heart disease Mild cyanosis at birth minimal auscultatory findings rapid onset of profound left heart failure as ductus arteriosus closes at 3-5 days of age Associated abnormalities mitral atresia aortic atresia Uniformly fatal without treatment Diagnosis often made prenatally by ultrasonography at 18-20 weeks. Diagnosis confirmed by echocardiogram. ECG shows right axis deviation and paucity of LV forces 2 Differential Diagnosis Other causes of heart failure in the first month coarctation cardiomyopathy Severe acute pulmonary disease Multiorgan failure from septicemia Treatment Continuous IV prostaglandin E1 maintains patency of ductus arteriosus Nitrogen added to inhaled air lowers inspired O2 to 21 increases pulmonary vascular tone and improves systemic perfusion Surgical palliation Norwood operation uses the RV as the systemic ventricle with an aortopulmonary shunt for pulmonary blood flow Cardiac transplantation is a second surgical option Prophylaxis for endocarditis required after the Norwood operation Pearl Only 50 of children with hypoplastic left heart in the United States are diagnosedprenatally by in utero ultrasound. 32 Current Essentials Pediatrics 2 Tetralogy of Fallot T of F Essentials of Diagnosis Most common cyanotic cardiac lesion. 10 of all congenital heart disease Constellation of defects large membranous VSD with overriding aorta obstructed right ventricular outflow tract pulmonary valve and infundibular hypoplasia right ventricular hypertrophy Cyanosis due to right-to-left shunting through the VSD appears by age 4 months. May be mild if right ventricular outflow obstruction is mild Systolic ejection murmur at upper left sternal border Hypoxemic spells Tet spells start during infancy sudden deep cyanosis dyspnea alteration in consciousness syncope decrease in murmur .
