Lecture about CHD beautiful and complete

Pediatric lecture

1. Pediatrics Congenital Heart Diseases 1 st part By: Dr.GOAT 🥇

2. Contents: -Classification -Pathophysiology -Signs & symptoms -Management CHDs

3. Major CHDs:- Ventricular Septal Defect: 30-35% * most common. Atrial Septal Defect Patent Ductus Ateriosus: It is not that common, but it is the most common in premature children. Coarctation of Aorta Tetralogy of Fallot: it's the most common c yanotic heart disease. Pulmonary valve stenosis: more common than aortic valve stenosis. Aortic valve stenosis D-Transposition of great arteries: most common cause of severe cyanosis in newborn (at birth). Introduction

4. Etiology: Mostly unknown Sometimes: associated with chromosomal abnormalities or other genetic disorders. 50% of Down syndrome have CHD. Trisomy 21: AVSD Trisomy 18: VSD Tris omy 13: PDA, VSD, ASD Turner syndrome: Coarctation of Aorta Cont…

5. Divided into 2 major groups: Cyanotic heart diseases. Acyanotic heart diseases, which is more common. The two main ones are left to right shunt (VSD, ASD, PDA, AVSD), and obstructive lesions (aortic stenosis, Coarctation of aorta) Diagnosis is confirmed by:- Echo in 95-98%, and in ≤ 5% require other modalities such as Cardiac CT/MRI or Cardiac Catheterization. Classification

6. Classification

7. Fetal Circulation

8. Acyanotic Heart Disease Left to Right Shunt lesions PDA AVSD VSD ASD Eisenmenger Syndrome

9. PDA is a common problem in premature infants. Pathology: There is a persistent patency of a normal fetal structure between the left PA and th e descending aorta , that is, about 5 to 10 m distal to the origin of the left subclavian artery.Patients are usually asymptomatic when the ductus is small. A large-shunt PDA may cause >> lower respiratory tract infection, Atelectasis, CHF (accompanied by tachypnea and poor weight gain). With pulmonary vascular obstructive disease ( Eisenmenger syndrome ), a right- to-left ductal shunt results in cyanosis only in the lower half of the body (i.e. differential cyanosis ). A grade 1-4/6 continuous ("machinery") murmur is best audible at the left infraclavicular area or upper left sternal border. Unlike PDA in premature infants, spontaneous closure of a PDA does NOT usually occur in full-term infants. This is because the PDA in term infants results from a structural abnormality of the ductal smooth muscle rather than a decreased responsiveness of the premature ductus to oxygen. PDA Indomethacin (NSAIDs) inhibits prostaglandin synthesis so it can be used for premature babies but not effective in term babies.

10. Most common form of CHD . Divided into:- Defect in membranous septum (70% of all VSDs)>>> Peri-membranous VSD-Defect in muscular septum (30% of all VSDs) Pathophysiology : L-R shunt (high pressure LV to low pressure RV) toward pulmonary circulation. Blood shunts during the whole of systole and not diastole. Small (restrictive) VSD: Asymptomatic but they have a high murmur. VSD

11. Holt-Oram Syndrome ASD secundom (M/C type). Clinical Features: Usually asymptomatic (even no murmur) because of low pressure difference between the two atria even if it was large. Symptoms if they present late as the RA enlarges when Afib occurs will occur 20-40years. Widely fixed splitted second heart sound normal physiology: During inspiration the intra-thoracic pressure is negative and this will suck the blood to the right ventricle increasing the venous return to the right side, therefore the right side cardiac output needs longer time to be pumped from the heart leading to a delay in the closure of the pulmonary valve and also because the right ventricular activity is weaker than that of the left which will further delay the closure of the pulmonary component of the second heart sound. This will make the splitting more evident during inspiration.- During expiration: the intra-thoracic pressure becomes positive and the lungs are compressed decreasing the right venous return and increasing the left venous return so the aortic valve closure will be nearer to that of the pulmonary valve, therefore splitting will be less evident. ASD

12. In ASD:There will be wide (because there is increased blood in the right side because of the shunt) and fixed i.e. in both inspiration and expiration(because during expiration there will be increase in the left venous return that will be shunted to the right side which will further delay the pulmonary closure) splitting. Prognosis: Complications might occur If left untreated to adult life. Heart conduction is in the right atrium; therefore, when it enlarges conduction is disrupted and forms: • Pulmonary vascular obstructive disease. • Atrial arrhythmias. • Paradoxical embolization (rare). ASD

13. Involves a defective closure of embryologic endocardial cushion tissue.AKA (Complete endocardial cushion defect – ECD) Of patients with complete ECD, 30% are children with Down syndrome. Of children with Down syndrome 40%have congenital heart defects, and 40% of the defects are ECD. • ECD is also a component of heart defects in asplenia or polysplenia syndrome. AVSD

14. If the defects are large enough to cause symptoms the presentation will start at the age of 6 to 9 wks why??? The pulmonary vascular resistance will be high so there is no big difference between the pulmonary vascular resistance and systemic resistance in the 1st few weeks of life so there will be less Lt to Rt shunting of blood so fewer symptoms but it will start to decrease until reach 1/3 only of the systemic resistance by the 6-9 wks so there’ll be huge shunt which will be manifested by: Recurrent chest infection + Sx of congestive heart failure. Lt to Rt Shunts ☆☆☆

15. Mx: Medical Mx: Usually, babies will present with HF Sx so we should treat them 1st in this way /
1)ABC 2)A D mit the Pt to the ICU initially. 3)Start Preload & Afterload reduction (⇣ preload by giving the pt diuretics -Lasix which is furosemide to reduce CO & ⇣ afterload which is systemic vascular resistance by giving the pt ACE inhibitors commonly Captopril so when the pressure in LV is low it will reduce the shunt. 4)Resp.Support (O2 or mechanical ventilation ) 5)Mx of infections if there is any. +prophylactic Abx until we do the operation. Then if The Pt's health improves we’ll continue on antifailure medications + NUTRITIONAL SUPPORT which is extremely important why? -Pt is having high metabolic rate and demand -also to reach the preferred weight for surgery which is not less than 5 Kg Lt to Rt Shunts ☆☆☆

16. Mx: Surgical Mx : The timing of surgery depends on : 1) I f the pt is controlled on med. O r no 2) G ood nutritional support 3) A symptomatic 4) S tart to gain weight So the usual age for doing the surgery if ↑↑↑ these 4 conditions are there is from 6-9Mo why??? To give time to the baby to gain wt to be large enough. Also, a lot of studies mentioned that by the age of 12 Mo the risk of Eisenmenger syndrome becomes very high. What are the benefits of surgery? P revents ⇣
1) HF 2)Repeated Chest infection 3)plum.HTN 4)FTT 5)IE Lt to Rt Shunts ☆☆☆

17. Lt to Rt Shunts ☆☆☆ Notes about ASD : Rarely present with symptoms because there is no big difference between Rt and Lt Atria (5 | 7 mmHg respectively) but when it is detected it should be closed and the typical age of closure is preschool-age So why do we do surgery for them? Because with time the increase in the flow to the RA can lead to dilatation of RA which is dangerous because RA contains most of the conduction system of the heart so we are afraid of arrhythmias.

Also no need for antifailure medications or prophylactic Abx because there is no big difference in pressure so there will be no lesions necessitate Abx .

18. Holt-Oram Syndrome ASD

19. Thank you! References: @ doclabsai -Medscape -Nelson Textbook