Lec. 1 - Congenital heart diseases (Part 1).pdf

Lec.39 Pediatrics Dr. Muneera Congenital heart diseases I Lec. 1 3rd April. 2017 Done by: Zainab Abdul Ghany. 2016-2017 ‫مكت...

Lec.39 Pediatrics Dr. Muneera Congenital heart diseases I Lec. 1 3rd April. 2017 Done by: Zainab Abdul Ghany. 2016-2017 ‫مكتب آشور لالستنساخ‬ 0 Congenital heart diseases These are abnormalities in the cardiocirculatory structures or function that are present at birth, even if it is discovered later. Incidence 0.8% in normal population. 2-6% in 2nd pregnancy after birth of 1st child with CHD. 20-30% if 2 other siblings have CHD. Etiology Multifactorial : genetic , environmental Genetic: 1. Chromosomal anomalies (Turner, Trisomies 18, 21). 2. Supracristal VSD in Asian. 3. Increase incidence if 1st degree relative affected. 4. Chromosomal deletion (chr. 22q11….. DiGeorge syndrome). 5. Cardiomyopathy. 6. Heritable arrhythmias Enviromental: Maternal DM Phenylketonuria Congenital rubella SLE Drugs (Lithium, ethanol, warfarin, thalidomide, antimetabolites, anticonvulsants) Classification Acyanotic CHD: a. Ventricular septal defects (VSD) 25% b. Atrial septal defects (ASD) 10% volume c. Patent ductus arteriosus (PDA) 10% load Lf d. Pulmonary stenosis 10% e. Coarctation of the aorta 8% pressure f. Aortal stenosis 6% load 1 Cyanotic heart disease: With Low pulmonary blood flow With High pulmonary blood flow 1. TOF 1. TGA 2. P. ATRESIA +/- VSD 2. Total anomalous pulmonary venous return 3. TRICUSPID ATRESIA 3. Truncus arteriosus 4. DORV+ PS 4. Single ventricle 5. Hypoplastic Lt. heart syndrome 5. EBSTEIN ANOMALY OF TV VENTRICULAR SEPTAL DEFECT (VSD) The most common CHD Anatomically classified into: 1-membranous VSD 80% 2-Muscular VSD 5% 3-Inlet VSD 5% Hemodynamically (functionally): classified into: 1- Small VSD (small Lt.-Rt. Shunt) 2-Moderate VSD 3-Large VSD Pathophysiology Lt  to  Rt shunt depend on: 1- Size (restrictive & large non-restrictive) 2- qp: qs ratio :(pulmonary to systmic blood flow) Small < 1.75:1 Large > 2:1 'When a small communication is present (usually 1.0 cm2), right and left ventricular pressure is equalized. 2 The functional disturbance caused by VSD magnitude of the L-R shunt depends on: size of VSD & degree of pulmonary vascular resistance not on the site of VSD. In large VSD There is no resistance to the flow, so there is large shunt and there will be progressive increase in right ventricular (RV) & pulmonary artery pressure, as a result of increase of the pulmonary vascular resistance which causes reverse shunt Rt-Lt. (Eisenmenger syndrome) which is irreversible…  In small VSD There is high resistance to the flow through the VSD so there is small Lt.-Rt Shunt and the pressure is normal in RV and pulmonary artery (PA). Clinical features Small VSD 1- Most common. 2- Asymptomatic. 3- Dx during routine examination. 4- Harsh, blowing holosystolic murmur. 5- Immediately in neonatal period Lt to Rt shunt minimal lead to that the murmur may not be heard. 6- In premature the murmur heard earlier. Large VSD Dyspnea, feeding difficulty, poor growth, profuse sweeting recurrent pulmonary infection. Cyanosis usually absent, but duskiness especially during infection. O/E: 1- Palpable parasternal lift. 2- Lateral displaced impulse. 3- Systolic thrill. 4- Holosystolic murmur less harsh. 5- Pulmonary component of 2nd heart sounds increased. 6- Mid diastolic rumbling murmur increased at apex = qp;qs ratio 2:1. 3 DIAGNOSIS: 1. ECG: a. small VSD - normal ECG b. large VSD - biventricular hypertrophy 2. CxR.: a. small VSD - normal b. large VSD - cardiomegaly, dilated pulmonary vessels (plethoric lung) 3. Echo: Two-dimensional and Doppler echo must be done in all patients to determine the following: a. Size b. Anatomical location c. Size & direction of intracardiac shunt d. The degree of pulmonary hypertension e. Present of associated lesion (as TOF) 4- Catheterization & angiography: A small number of patients with VSD requires cath. (because echo is more sensitive & more specific). a. Provide a clear anatomical picture of the location and no. of VSD in patients when surgery is required b. Estimation of magnitude of the shunt & pulmonary vascular resistance (to know if the patient is still operable or not). c. Close some muscular VSDs with catheter derived devices. Prognosis and natural history Course depends on the size:  Small VSD ( 30-50%) close spontaneously frequently during 1st 2 years of life o Muscular 80%. o Membranous 35%  Small  asymptomatic  if unoperated  long term sequalies (arrhythmia, sub-aortic stenosis , exercise intolerance ).  Large VSD less likely to close spontaneously. 8% may close completely. repeated infection , repeated HF,FTT. 4  Large VSD: most patients need surgical repair, in the 1st year of life,  Without surgical repair, most patients will develop pulmonary hypertension and some reach to Eisenmenger syndrome (10%), but 5% wall develop infundibular & pulmonary stenosis.  Those with supracristal VSD at risk for aortic regurgitation.  Small % acquired infundibular pulmonary stenosis  protect pulmonary circulation from over circulation.  There is risk of infective endocarditis irrespective of defect size. Treatment Small VSD 1- Reassured the parents. 2- Encouraged patient to have normal life, no restriction of physical activity. 3- Surgical repair not encouraged. 4- Protect against IE with AB. 5- Can monitor the patient with: a. Clinical examination b. ECG for evidence of PH c. Echo Large VSD Medical Rx: To control HF and prevent development of PH and tx of resp. infection nutritional support prophylaxis SBE Surgical repair: Either pulmonary arty banding or total surgical repaire Indications 1- Any age with large defects in whom clinical features and failure to thrive can’t be controlled medically 2- Infants between 6-12 months with large defects associated with PH even if symptoms controlled by medical Rx. 3- More than 24 months old age and qp:qs > 2:1. 4- Patient with supracristal VSD of any size because of risk of development of aortic regurgitation. Catheterization based tx; most muscular VSD and some membranous can closed by devices place during cath. 5 ATRIAL SEPTAL DEFECT (ASD) An opening in the intra-atrial septum other than patent foramen ovale more common in females; F:M ratio is 3:1. It has 3 types: 1-Primum ASD (in lower part) 10% 2-Secondum ASD (in the middle) 80% 3-Sinus venosus (in the upper part) 10% HEMODYNAMIC EFFECT: There will be chronic Lt-Rt. Shunt which causes volume overload on the Rt. Sided cardiac structures & result in their dilatation & increase of pulmonary blood flow. Clinical features Most often asymptomatic. In younger children may cause subtle FTT. In older children lead to exercise intolerance. O/E: Mild Lt precordial bulge. Loud 1st heart sound. 2nd heart sound split widely and fixedly. Systolic ejection murmur. Short rumbling mid – diastolic murmur with the bell of the stethoscope =qp:qs at least 2:1. DX: A. CXR Cardiomegaly of RV configuration Round apex peak Increase pulmonary marking B. ECG: Right axis deviation (RAD) Incomplete RBBB Peaked P-wave (RA enlargement) C- Echo: Trans-thoracic & trans-esophageal echocardiography is essential for Dx. D. Cardiac Catheterization: Not essential for Dx, indicated in: Therapeutic aim & 'Exclude associated cardiac anomaly. 6 Natural history ASD is a benign lesion rarely causes heart failure or pulmonary hypertension in the 1 st decade of life Rarely complicated by infective endocarditis Rarely closed spontaneously after infancy Treatment If patient Symptomatic or has qp :qs ratio at least 2:1 Then the treatment is: o Surgery o Transcatheter device closure The surgery done after 1 yr. of age and before enterance to school. Prognosis May close spontaneously during infant. Mau be tolerated during childhood. Symptoms not appear until 3rd decade or later and late manifestations are: 1. PH 2. Atria dysarrhythmias 3. Mitral or tricuspid insufficiency 4. HF Infective endocarditis rare and need no prophylaxis with AB. 7 Atriovantricular septal defect (endocardial cushion defect)  It is a group of anomalies sharing a defect at the site atrioventricular septum and abnormality in the atrioventricular valve.  Common in downs syndrome, so all patients with downs syndrome should Have cardiac evaluation if symptomatic or before 6 months of age  Equal no. of male and females are affected CLASSIFICATION: 1- Partial: ASD primum, clefted mitral valve.intact VSD 2- Complete: ASD primum, large inlet VSD, common single atrioventricular valve. C/F: 1- Partial: either asymptomatic (mainly) or mild symptoms. O/E: ASD murmur of mitral regurgitation. 2. Complete: as the above with heart failure and/or pulmonary vascular disease. Pathophysiology OP: Lt  Rt. Shunt. Mitral insufficiency. PA pressure normal. C/F of ASD. AVSD : Lt  Rt shunt at atrial + ventricular level. Valvular insuffiency  volume load on one or both ventricles. Pulmonary vascular resistance  Rt  Lt shunt  cyanosis. Diagnosis 1. CXR : marked cardiac enlargement , pulmonary vascularity , PA enlargement. 2. ECG: Rt axis deviation of QRS, RBBB, RVH. 3. ECHO : RV enlargement , septal deficiency. 4. CATHE. 5. Selective LV ventriculography. Treatment OP : surgical correction. Complete AVSD : risk of PHPT during 1st 6-12 mo.  surgery in early infancy Sometimes do pulmonary banding if too small baby or associated with deformity that make surgery risky. 8 NATURAL HISTORY: It depends on the size of various atrial and ventricular defects and the amount of mitral regurgitation. The ostium primum ASD with no mitral regurgitation has the same benign natural history of simple secondum ASD, but with complete AV-canal defect, heart failure and/or pulmonary vascular disease may occur. PATENT DUCTUS ARTERIOSUS (PDA)  It is a channel that connect the pulmonary artery with the descending aorta (isthumus part). It results from the persistence of patency of the fetal ductus arteriosus after birth.  It is the most common lesion in infant of mothers with congenital rubella, PDA more common in females.  Normally functional closure of ductus arteriosus occurs at 10-15 hr after birth. If it persist opened after pulmonary vascular resistance falls leads to aortic blood shunts to pulmonary artery.  More common in female  Aortic side ( distal to the origin of lt subclavian art.)  Pulmonary side ( at the bifurication ) Why it is not closed? Premature ( normal structure ) due to hypoxia and immaturity. In term baby  have structural abnormality. In term baby if persist beyond 1st few weeks  means not closed spontaneously. Most of cases in premature  closed spontaneously. 10% associated with other CHD. Pathophysiology Lt  Rt shunt depends:  Size of defect  Ratio of pulmonary : systemic vascular resistance 9 Clinical features Small Asymptomatic. Heart size may be abnormal Large Hf , growth retardation Bounding peripheral pulse Wide pulse pressure Large heart Apical impulse prominent Thrill Machinery murmur Mid-diastolic murmur at apex DIAGNOSIS:  ECG: In small PDA, it is normal, but large PDA, there is normal axis deviation, left ventricular hypertrophy (LVH) or biventricular hypertrophy.  Chest X-ray: Cardiomegaly, plethoric lung, and prominent pulmonary conus. Treatment Closure irrespective of age. Endomethacin is often effective in closing the PDA in the premature neonate by decreasing PGE1 levels. Closure by : 1. Thoraco-scopic (lower postoperative discomfort and scarring). 2. Trans-catheter: o Small  coil. o Large  sac in which several coils released or umbrella –like device. THANK YOU Edited by: Zainab Abdul Ghany. 10