10. Congenital heart defects.pdf

11/10/2023 1 CONGENITAL HEART DEFECTS BLOCK ONE 2023 CLASS 11/10/2023 2 Objectives By the end of the lesson, the learner will be able to: Describe the congenital abnormalities and their manag...

11/10/2023 1 CONGENITAL HEART DEFECTS BLOCK ONE 2023 CLASS 11/10/2023 2 Objectives By the end of the lesson, the learner will be able to: Describe the congenital abnormalities and their management 11/10/2023 3 Definition Congenital heart defects (CHD) are as a result of malformations of the heart or its associated blood vessels which are present at birth 11/10/2023 4 Introduction The majority of congenital anomalies of the heart are present 6 weeks after conception & most anomalies compatible with 6 months of intrauterine life permit live offspring at term Number of children reaching adulthood with congenital heart disease has increased over the last 5 decades due to advances in diagnosis, medical, critical and surgical care  11/10/2023 5 NORMAL HEART  11/10/2023 6 Blood flow through the normal heart 11/10/2023 7 11/10/2023 8 Fetal circulation 11/10/2023 9 Circulation after birth  11/10/2023 10 Fetal Circulation There are 4 shunts in fetal circulation: Placenta- Oxygen and nutrients from the mother's blood are transferred across the placenta to the fetus Foramen ovale- bypass the lungs and moves blood from the right atrium to the left atrium Ductus arteriosus - moves blood from the pulmonary artery to the aorta Ductus venosus- passes highly oxygenated blood through the liver to the inferior vena cava and then to the right atrium of the heart.  11/10/2023 11 Fetal Circulation Oxygenated blood enters the fetus via the umbilical vein The blood bypasses the liver via the ductus venosus and mixes with deoxygented blood from the inferior and superior venacava The blood drains into right atrium Blood is shunted from the right to left atrium via the foramen ovale due to difference in pressure  11/10/2023 12 Fetal Circulation Most of the blood flows into the left atrium via the foramen ovale Blood in the left atrium flows to the left ventricle then to the aorta and the rest of the body Some blood flows from the right atrium to the right ventricle From right ventricle to the pulmonary artery where it is shunted away from the lungs by the ductus arteriosus into the aorta Deoxygenated blood flows back to the mother via the umbilical arteries 11/10/2023 13 CARDIOPULMONARY CHANGES AT BIRTH Cessation of blood flow in the umbilical vein results in closure of the ductus venosus and becomes ligamentum venosum Right Atrial Pressure (RAP) pressure falls as a result of closure of the ductus venosus Closure of the foramen ovale is as a result of ↑ Left Atrial Pressure (LAP) in excess of Right Atrial Pressure (RAP) and becomes fossa ovalis  11/10/2023 14 CARDIOPULMONARY CHANGES AT BIRTH Ductus arteriosus closure is due to ↑ arterial oxygen saturation which decreases prostaglandins circulation The ductus arteriosus becomes the ligamentum arteriosum  11/10/2023 15 Cardiac Defects  Patent Ductus Arteriosus  Atrial Septal Defect  Ventricular Septal Defect  Tetralogy of Fallot  Transposition of the Great Arteries  Coarctation of the Aorta  Anomalous Venous Return  Pulmonary stenosis  Aortic stenosis 11/10/2023 16 AETIOLOGY Genetic causes; interaction of several genes- Risk of recurrence if 1st degree relative is affected Chromosomal abnormalities e.g. Downs syndrome is associated with (AVSD) and Turners syndrome associated with coarctation of aorta Environmental factors or adverse maternal conditions e.g. Congenital rubella syndrome associated with PDA, drugs like lithium associated with pulmonary or aortic stenosis 11/10/2023 17 Presenting complaints/signs  Failure to thrive  Fast breathing  Exercise intolerance  Oedema  Easy fatigability  Hepatomegaly,  Chest in drawing  spleenomegaly  Sweating during feeding  Clubbing  Bluish spells/Cyanosis  Palpitation  Fever  Convulsions 11/10/2023 18 Classification of congenital heart disease  Congenital Heart diseases have 2 types:  Acyanotic congenital heart diseases (68%)  Cyanotic congenital heart diseases (22%)  11/10/2023 19 Acyanotic congenital heart diseases  Occurs when blood flows from the left side of the heart to the right side of the heart due to a structural defect (hole) in the interventricular septum  Patients retain normal levels of oxyhemoglobin saturation in systemic circulation hence acyanotic  Also referred to as left to right shunting  11/10/2023 20 Common Acyanotic lessions  Ventricular septal defects (VSD)  Atrial septal defects (ASD)  Atrio-ventricular septal defects (AVSD)  Patent ductus arteriosus (PDA)  Pulmonary stenosis (PS)  Aortic stenosis (AS)  Coarctation of aorta 11/10/2023 21 Common Cyanotic lessions  Tetralogy of fallot (TOF)  Tricuspid Atresia  Transposition of great vessels  Truncus arteriosus 11/10/2023 22 ACYANOTIC CONDITIONS 11/10/2023 23 Common Acyanotic lessions  Ventricular septal defects (VSD)  Atrial septal defects (ASD)  Atrio-ventricular septal defects (AVSD)  Patent ductus arteriosus (PDA)  Pulmonary stenosis (PS)  Aortic stenosis (AS)  Coarctation of aorta  11/10/2023 24 Ventricular Septal Defect  VSD – is an abnormal opening in the ventricular septum, which allows free communication between the Rt & Lt ventricles 11/10/2023 25 Atrial Septal Defect ASD is an opening in the atrial septum permitting free communication of blood between the atria.  11/10/2023 26 Atrioventricular Septal Defect  It results from incomplete fusion of the endocardial cushions, which help to form atrial septum, the ventricular septum and the septal leaflets of the tricuspid and mitral valves  Treatment is via surgery 11/10/2023 27 Complete Atrioventricular septal defect 11/10/2023 28 Patent Ductus Arteriosus  Occurs due to persistence of the ductus arteriosus  Normally closes in the 1st wk of life  As a result of higher aortic pressure, blood shunts L to R through the ductus from Aorta to PA (pulmonary artery) 11/10/2023 29 11/10/2023 30 PATENT DUCTUS ARTERIOSUS 11/10/2023 31 Pulmonary Stenosis  Pulmonary Valve Stenosis is a rare acyanotic congenital heart defect that involves a defect in the pulmonary valve  11/10/2023 32 Aortic Stenosis Aortic Stenosis is an obstruction to the outflow from the left ventricle at or near the aortic valve 11/10/2023 33 Coarctation of the Aorta Coarctation- refers to narrowing Coarctation of aorta is when a section of the aorta is narrowed to an abnormal width resulting in severely reduced blood flow 11/10/2023 34 CYANOTIC CONDITIONS  11/10/2023 35 Cyanotic congenital heart diseases  Occurs when a mixture of oxygenated and deoxygenated blood enters the systemic circulation  Common cyanotic conditions include:  Tetralogy of fallot (TOF)  Tricuspid Atresia  Transposition of great vessels  Truncus arteriosus  11/10/2023 36 Tetralogy of Fallot  TOF involves four heart malformations which present together:  Pulmonary stenosis  Overriding aorta (displacement of the aorta)  VSD (ventricular septal defect)  Right ventricular hypertrophy- The right ventricle is more muscular than normal to deal with the increased obstruction to the right outflow tract 11/10/2023 37 TETRALOGY OF FALLOT  11/10/2023 38 Transposition of the Great Arteries  Aorta arises from RV and Pulmonary Arteries from LV  Without an abnormality, life would not be possible  ASD  VSD  PDA 11/10/2023 39 11/10/2023 40 TOTAL ANOMALOUS PULMONARY VENOUS RETURN (TAPVR)  11/10/2023 41 Anomalous Venous Return  All four pulmonary veins drain to the right side.  Return of pulmonary venous blood to the right atrium instead of the left  ASD is present to sustain life  Surgical correction is via re-implantation of pulmonary veins 11/10/2023 42 Truncus arteriosus Truncus arteriosus, also known as common truncus, is a rare defect of the heart in which a single common blood vessel comes out of the heart, instead of the usual two vessels (the main pulmonary artery and aorta) Persistent truncus arteriosus (TA) is a rare, congenital, cyanotic heart defect characterized by a ventricular septal defect (VSD), a single truncal valve, and a common ventricular outflow tract (OT) 11/10/2023 43 TRUNCUS ARTERIOSUS 11/10/2023 44 Ct.. Systemic venous blood and pulmonary venous blood mixes at the VSD level, and the resulting desaturated blood is ejected into the single outflow tract or truncus Without surgical intervention, death in infancy is unavoidable 11/10/2023 45 Types of truncus arteriosus 11/10/2023 46 Types of truncus arteriosus 11/10/2023 47 Clinical manifestation (s/s) Cyanosis Poor feeding Pounding heart Irritability Excessive sleepiness Poor growth Dyspnea Tachypnea  11/10/2023 48 Tricuspid atresia Tricuspid atresia (pronounced try- is a birth defect of the heart where the valve that controls blood flow from the right upper chamber of the heart to the right lower chamber of the heart doesn't form at all 11/10/2023 49  11/10/2023 50 Summary  Described the congenital anomalies:  Patent Ductus Arteriosus  Atrial Septal Defect  Ventricular Septal Defect  Tetralogy of Fallot  Transposition of the Great Arteries  Coarctation of the Aorta  Anomalous Venous Return  Pulmonary stenosis  Aortic stenosis 11/10/2023 51