Congenital Heart Defects By Kimberly Napper Congenital Heart
Congenital Heart Defects By Kimberly Napper
Congenital Heart Disease occurs when the heart or blood vessels near the heart do not develop properly before birth.
Congenital Heart Defects may include structural defects, congenital arrhythmias, and cardiomyopathies • are present in about 1% of live births • are the most common congenital malformations in newborns •
Definitions of terms: n Atresia- congenital absence or closure of a normal body opening or tubular structure n Prostaglandins- hormones important in the mediation of inflammation, platelet aggregation, vasodilation, pain reception, & maintenance of patent ductus arteriosus n Prostaglandin inhibitors- nonsteroidal & steroid anti-inflammatory agents
Definitions of terms: n Stenosis- constriction or narrowing of a passage or orifice n Subacute Bacterial Endocarditis (SBE) - heart valve infection not evident for weeks or months; usually streptococcal; often develops on abnormal heart valve n SBE prophylaxis- to prevent SBE
With Normal Heart Anatomy, oxygen-depleted blood is pumped from the right side of the heart, through the pulmonary artery, to the lungs where it is oxygenated. http: //en. wikipedia. org/wiki/Congenital_heart_defects
With Normal Heart Anatomy, the oxygen-rich blood then returns to the left heart, via the pulmonary veins, and is pumped through the aorta to the rest of the body. http: //en. wikipedia. org/wiki/Congenital_heart_defects
Normal Blood Flow http: //www. wellesley. edu/Biology/Courses/111/Adult. Heart. gif
Fetal Circulation (see Wong p. 823) n Umbilical vein supplies oxygen & nutrients from the placenta n Right side of heart has higher pressures than left side n Foramen ovale allows blood to cross from right to left atrium n Ductus arteriosus allows most of blood from pulmonary artery to enter the aorta
Foramen Ovale
Transition from Fetal Circulation n Clamping of umbilical cord increases systemic pressure n Expansion of lungs with air n Increased oxygen – decreases pulmonary pressure (vasodilation) – promotes closure of ductus arteriosus n Closure of foramen ovale as left atrial pressure > right atrial pressure
Types of Congenital Heart Defects (Classifications) Wong p. 824 Acyanotic- left to right shunting of blood (↑pulmonary blood flow) Cyanotic- right to left shunting of blood (↓pulmonary blood flow)
Acyanotic Defects (based on blood flow patterns within heart) obstruction to blood ↑pulmonary flow out of the heart • ventricular septal n pulmonary stenosis defect n aortic stenosis • atrial septal defect n coarctation of the aorta • patent ductus arteriosus
Cyanotic Defects (based on blood flow patterns within heart) ↓pulmonary flow n Tetralogy of Fallot n Tricuspid Atresia Mixed blood flow • Transposition of the Great Arteries • Truncus Arteriosus
Acyanotic Defects Blood Flow Patterns with left to right shunting: (↑pulmonary blood flow) ventricular septal defect (VSD) (30% of all congenital heart defects) • atrial septal defect (ASD) • patent ductus arteriosus (PDA) •
Acyanotic Defects Blood Flow Patterns without shunting: n pulmonary stenosis (PS) n aortic stenosis (AS) n coarctation of the aorta (coarc)
Acyanotic Defects Blood Flow Patterns • Increased Pulmonary Flow • ASD, VSD, PDA • Obstructed blood flow out of the heart • PS, AS, Coarc
Congenital Heart Defects Blood Flow Patterns Obstructed blood flow out of heart n Coarctation of aorta n Aortic stenosis n Pulmonic stenosis Mixed blood flow n Transportation of the great vessels n Truncus arteriosus
Congenital Heart Defects Blood Flow Patterns Increased pulmonary blood flow n Atrial and ventricular septal defects n Patent ductus arteriosis Decreased pulmonary blood flow n Tetralogy of Fallot n Tricuspid atresia
Atrial Septal Defect (ASD) n Abnormal opening between the atria n Allows blood from higher-pressure left atrium to flow into lower-pressure right atrium (left to right shunt) n ↑pulmonary blood flow n right heart dilation and pulmonary overcirculation
ASD n May have no symptoms until later in life n May have a soft systolic murmur n Repair can prevent serious problems later in life. (May lead to…) – Heart Failure (HF) – Atrial dysrhythmias – Pulmonary vascular obstructive disease – Emboli formation
Bubble Study to Confirm ASD n http: //www. youtube. com/watch? v=3 dssb Deow 50 n http: //youtu. be/3 dssb. Deow 50
ASD http: //www. americanheart. org/images/Image. Picker/12998 -inter-full. jpg
Left to Right Shunt (Wong 9 th ed. p. 825) The blood from the left side is spilling back to the right side, which may “flood” the lungs! http: //en. wikipedia. org/wiki/File: Atrial_septal_defect-en. png
Transcatheter Closure of ASD http: //www. rjmatthewsmd. com/Definitions/atrial_septal_defect. htm
Transcatheter Closure of ASD http: //www. rjmatthewsmd. com/Definitions/atrial_septal_defect. htm
Ventricular Septal Defect (VSD) n Abnormal opening between the ventricles n Size & location of defect may vary n Allows blood from higher-pressure left ventricle to flow into lower-pressure right ventricle (left to right shunt) ↑pulmonary blood flow n Wong 9 th ed. p. 825, 826, 834 n
VSD http: //www. americanheart. org/images/Image. Picker/13026 -inter-full. jpg
VSD § HF is common § due to flooding of the lungs & right ventricle ↑ load Heart may enlarge from the added work § Murmur (sound of turbulent blood flow) §
Respiratory distress “head bobbing” & retractions n http: //www. youtube. com/watch? v=q 0 b. Hw. M ay. CJY n http: //www. youtube. com/watch? v=NBA 9 iigi Dgk These are signs of respiratory distress! n If R/T CHF, what medication should you give? n
VSD Wong 9 th ed. p. 825, 826, 834 § Increased pulmonary blood flow will cause prominent pulmonary vasculature (seen on CXR). n High blood pressure may occur in the lungs' blood vessels (because more blood is there) n Over time, increased pulmonary hypertension may permanently damage the blood vessel walls
VSD may exhibit increased pulmonary vasculature. http: //www. crkirk. com/thumbnail/common/vsd. htm
VSD on Echocardiogram http: //www. crkirk. com/thumbnail/common/vsd. htm
VSD n Small defects may close without surgery. n Small defects may be repaired surgically with a purse -string approach. n Large defects may be repaired using a Dacron patch. n Cardiopulmonary bypass is required for surgical repair. n Requires SBE prophylaxis until repaired.
Ventricular Septal Defect http: //www. medmovie. com/cardiac 1/pages/0130 i. VSD. htm
After Heart Surgery
Growing up pretty!!
Growing strong!
Patent Ductus Arteriosus n The 6 th most common congenital heart defect (5 to 10% of all children with congenital heart disease) n Occurs twice as often in girls as in boys n Depending on the size of the PDA and the condition of the lungs, there may be no symptoms or severe heart failure. http: //www. congenitalheartdefects. com/typesof. CHD. html#PDA
Patent Ductus Arteriosus (PDA) n In utero, the ductus is a normal connection between the aorta and the pulmonary artery n At birth, hormonal changes normally cause its closure n Failure to close may cause excessive blood flow to the lungs
Patent Ductus Arteriosus http: //en. wikipedia. org/wiki/Image: Patent_ductus_arteriosus. jpg
Patent Ductus Arteriosus (PDA) n The pressure in the aorta is higher than that of the pulmonary artery during both systole and diastole. n PDA blood shunting will occur from left to right during both systole and diastole. n The pulmonary arteries will dilate due to the increased pulmonary blood flow
Blood Flow through Ductus in Fetal Circulation http: //www. wellesley. edu/Biology/Courses/111/Duct. Art. gif
Patent Ductus Arteriosus (PDA) Wong 9 th ed. p. 827 S/S, if hemodynamically significant n CHF/respiratory distress – congestion in the lungs – prominent pulmonary vascular markings seen on CXR n Machinery-like murmur n Widened pulse pressure n Bounding pulses n Pedal & periorbital edema
Pedal Edema in Infant http: //newborns. stanford. edu/Photo. Gallery/Foot. Edema 1. html
Patent Ductus Arteriosus (PDA) n May be “ligated” in surgery n May be closed in cath lab by inserting specially designed coils, which block blood flow in the vessel n May be closed medically with Indomethicine (blocks Prostaglandins) – Ibuprofen as an alternative (piloted in 2003)
PDA & Indomethacin Ø Inhibition of prostaglandin synthesis permits constriction of the PDA Ø FDA-approved Indomethicine for use: – When S/S persist after 48 hours of conservative treatment: § fluid restriction, diuretics, and respiratory support. – In premature infants weighing 500 to 1750 grams
PDA & Indomethacin n Less effective after 7 days of age n Gastrointestinal problems – abdominal distention – bleeding – gastric perforation – transient ileus – vomiting n Renal function impairment n Bleeding problems n Hypoglycemia
Patent Ductus Arteriosus (PDA) n Shunting of blood can also be right to left, depending on the difference in pressures between systemic & pulmonary circulation n Blood flow will follow the path of least resistance n PDA may be life-saving in some cases n Prostaglandin (PGE 1) will be given IV to keep ductus from closing in these cases
Prostaglandin E 1 Studies performed prior to the initiation of prostaglandin therapy for central cyanosis: n Hyperoxic Challenge Test n Chest x-ray: Decreased pulmonary vascularity n Serum glucose n Hematocrit n Adequate ventilation n Arterial Blood Gases http: //www. uihealthcare. com/depts/med/pediatrics/iowaneonatologyhandbook/pharmacology/prostaglandine 1. html
Prostaglandin E 1 n Definitive echocardiography and cardiac catheterization will clearly identify infants with ductal dependent pulmonary blood flow n Prostaglandin E 1 is infused continuously by pump via a large peripheral vein or umbilical line. http: //www. uihealthcare. com/depts/med/pediatrics/iowaneonatologyhandbook/pharmacology/prostaglandine 1. html
Echocardiogram for Diagnosis
Prostaglandin E 1 n Monitor – respiratory rate – Temperature – blood pressure – arterial blood gases and p. H n Three common side effects – apnea (12%) – fever (14%) – flushing (10%)
Obstruction to Blood Flow out of Heart Obstruction defects n An obstruction is a narrowing that partly or completely blocks the flow of blood. n Obstructions called stenoses can occur in heart valves, arteries or veins. n The three most common forms are pulmonary stenosis, aortic stenosis and coarctation of the aorta.
Pulmonary Stenosis (PS) n n n The pulmonary or pulmonic valve is between the right ventricle and the pulmonary artery. It opens to allow blood to flow from the right ventricle to the lungs. A defective pulmonary valve that doesn't open properly is called stenotic. This forces the right ventricle to pump harder than normal to overcome the obstruction. If severe, may be a cyanotic defect.
Pulmonary Stenosis (PS) http: //www. americanheart. org/images/Image. Picker/13014 -inter-full. jpg
Pulmonary Stenosis (PS) n Treatment is needed when the pressure in the right ventricle is higher than normal. n In most children, the obstruction can be relieved by a procedure called balloon valvuloplasty. n Others may need open-heart surgery. n Requires SBE prophylaxis
Critical Pulmonary Stenosis/ Pulmonary atresia n No blood flow to lungs through pulmonic valve (total fusion of commissures) n Decreased pulmonary vasculature (seen on CXR) n Hypoplastic right ventricle may accompany n Cyanosis if PDA closes n PDA needed for survival until surgical repair n Prostaglandins to keep ductus open
Aortic Stenosis (AS) n A normal valve has three leaflets (cusps). n A stenotic valve may have only one cusp (unicuspid) or two cusps (bicuspid), which are thick and stiff. n The left ventricle will have difficulty in pumping blood to the body through this abnormal valve.
Aortic Stenosis n Symptoms may be severe in some infants n Most children have no symptoms n Some children may have chest pain, unusual tiring, dizziness or fainting n The need for surgery depends on how bad the stenosis is
Aortic Stenosis n Valve opening may be enlarged by balloon valvuloplasty or surgery. n The valve will remain deformed. n The valve may need to be replaced with an artificial one.
Aortic Stenosis n Lifelong medical follow-up is required n AS may worsen over time, and surgical relief of a blockage is sometimes incomplete n Some exercise may be restricted (like heavy lifting) n SBE prophylaxis is required
The Aorta n The aorta is the body's main artery n It distributes oxygen-rich blood to all parts of the body except the lungs n The first branches of the aorta go to the upper body (arms and head) n After that, blood goes to the lower body (abdomen and legs)
Coarctation of the Aorta Wong 9 th ed. p. 827, 828 n n Is a narrowing of the aorta between the upper-body artery branches and the branches to the lower body May include aortic valve abnormalities May be associated with other cardiac defects SBE prophylaxis indicated http: //www. yourdictionary. com/images/ahd/ jpg/A 4 aorta. jpg
Coarctation of the Aorta http: //www. medmovie. com/cardiac 1/pages/0088 i. Coarct. Ao. htm
Coarctation of the Aorta n Increases blood pressure in the arms and head – Average B/P in a newborn is 64/41. – Average B/P in a child 1 month - 2 years is 95/58. n Reduces blood pressure in the legs n Diminished pulses in lower extremities n Seriously strains the heart n Leads to cardiomegaly n Leads to CHF (heart failure)
Severe Coarctation of Aorta n In severe cases, cyanosis if PDA closes n Patient needs PDA for survival until surgical repair n Prostaglandins (PGE 1) to keep ductus open
Coarctation of the Aorta
Coarctation of Aorta n Balloon repair – Risk of restenosis or aneurysm n Surgical repair – Preferred in infants < 7 months
…but only for 10 minutes
Cyanotic Defects (decreased pulmonary flow) n Tricuspid Atresia n Tetralogy of Fallot n Transposition of the Great Vessels n Truncus Arteriosus
Tricuspid Atresia n No tricuspid valve so no blood can flow from the right atrium to the right ventricle n Right ventricle is small and not fully developed n Survival depends on presence of ASD/VSD n At birth, the PFO and PDA provide mixing n Prostaglandin E 1 to prevent ductal closure prior to surgical repair
Tricuspid Atresia Blood Flow: n right atrium → ASD → left atrium → n Most of this blood flows left ventricle → aorta → body n The rest flows through the VSD → small right ventricle → pulmonary artery → lungs n Because of poor pulmonary circulation, the child looks blue.
Tricuspid Atresia http: //www. americanheart. org/images/Image. Picker/13022 -inter-full. jpg
Tricuspid Atresia repair requires multiple procedures n Atrial septostomy in cath lab n Pulmonary to systemic artery anastomosis (Blalock and Taussig (BT) shunt) n Bidirectional Glenn shunt at 6 -9 months (2 nd stage) n Modified Fontan procedure n Wong 9 th ed. p. 831
BT Shunt for Tricuspid Atresia http: //tarheelhemangiomas. tripod. com/sitebuildercontent/sitebuilderpictures/modifiedheart. jpg
Bidirectional Glenn Shunt for Tricuspid Atresia http: //www. severinbrenny. com/shunt. jpg
http: //www. severinbrenny. com/fontan_operation. html
Nursing Considerations re: Tricuspid Atresia repair n No blood pressures or venipunctures in left arm of patients who had Glenn procedure (left subclavian artery used) n Family support & teaching regarding multiple surgeries & mortality rate ~10%
Tetralogy of Fallot 4 Key Features: 1. Ventricular Septal Defect (a hole between the ventricles) 2. Pulmonary Stenosis (obstruction from the right ventricle to the lungs) 3. Overriding Aorta (the major artery from the heart to the body lies directly over the ventricular septal defect) 4. Right Ventricular Hypertrophy (thickened muscle develops)
Tetralogy of Fallot n Boot-shape on CXR n Often blue (cyanotic) since some oxygen-poor blood is pumped to the body n Blood from both ventricles (oxygen-rich and oxygenpoor) is pumped into the body since the aorta overrides the ventricular defect and there's pulmonary stenosis n May have pulmonary atresia (pulmonary valve completely obstructed)
Tetralogy of Fallot http: //www. americanheart. org/images/Image. Picker/13020 -inter-full. jpg
Tetralogy of Fallot boot-shape on CXR http: //pediatriccardiology. uchicago. edu/MP/Radiology/cxrtof. htm
Surgical Treatment of Tetralogy of Fallot n In small and very blue infants, a shunt operation may be done first to provide adequate blood flow to the lungs. n The shunt is built between the aorta and the pulmonary artery n The shunt is removed when a complete intracardiac repair is done later
http: //www. americanheart. org/presenter. jhtml? identifier=11071#
“Tet Spell” (hypercyanotic spell) n Wong 9 th ed. p. 841 http: //affinity-health. adam. com/graphics/images/en/18134. jpg
Tetralogy of Fallot Knee-Chest Positioning to relieve “Tet Spells” http: //www. bing. com/images/search? q=squatting+with+tetralogy+of+fallot&go=&qs=bs&form=QBIR&adlt=strict#view=detail&id=A 56 E 12 D 9 B 28879308 E 21 CF 630 E 9 D 1 FA 90638 B 697&selected. Index=6
Tetralogy of Fallot & Squatting Position http: //www. bing. com/images/search? q=squatting+with+tetralogy+of+fallot&go=&qs=bs&form=QBIR&adlt=strict#view=detail&id=3 D 6 3338 F 1039662 ADDA 61062 F 2 CD 9243 B 68 ECAF 3&selected. Index=233
Before First Surgery
Steri-Strips at Sternotomy Site
Years Later As she grew, her shunt was no longer big enough to provide sufficient blood flow to her lungs. It was time for her “big girl” surgery.
Mixed blood flow n Transportation of the Great Vessels n Truncus Arteriosus
Transposition of the " Great Vessels” Ø Vena cavae Ø Pulmonary artery Ø Pulmonary veins Ø Aorta http: //en. wikipedia. org/wiki/Great_vessels
Transposition of the Great Vessels or Great Arteries n “Egg on a String” on CXR n Aorta comes off RV (right ventricle) n Pulmonary Artery comes off LV n Cyanosis – Less severe if large ASD, VSD, or PDA – CHF if ASD, VSD, or PDA n Patent Foramen Ovale (PFO) commonly present
Transposition of Great Arteries with “egg on a string” CXR http: //pediatriccardiology. uchicago. edu/MP/Radiology/cxrtga. htm
Transposition of Great Arteries (TGA) n PDA, PFO, & septal defects allow mixing of blood (to get flow to the lungs) n Prostaglandins to keep ductus open, if no other means of mixing left & right circulation (Wong 9 th ed. p. 832) n Balloon Atrial Septostomy to establish mixing n Surgical switch of vessels
Transposition of Great Vessels http: //www. medmovie. com/cardiac 1/pages/0120 i. Rashkind. Baby. htm
Transposition of the Great Arteries http: //www. medmovie. com/cardiac 1/pages/0125 i. Trans. Art. Surg. htm
Truncus Arteriosus n Boot shape on CXR n Single vessel that overrides both ventricles – pulmonary artery & aorta share a trunk n Blood from left & right mix in single vessel n Hypoxemia n ↑ pulmonary flow (R/T pressures) n ↓ systemic blood flow (R/T pressures)
Truncus Arteriosus
Truncus Arteriosus n Surgical repair in first month of life – Closure of VSD – Grafts to connect pulmonary arteries to right ventricle
Truncus Arteriosus n Post repair complications – CHF common – Pulmonary hypertension – Dysrhythmias – Mortality >10% – Future surgeries required to replace conduits
Developmental Care of the Sick Infant http: //dev. snoedel. com/wpcontent/uploads/2012/12/snoedel_nicu. jpg http: //www. babyfirst. com/en/neonatal-care/developmental-care. php# Support infant’s limbs to promote flexion
Promote Bonding n n n n Wong 9 th ed. p 843 Allow parents to hold baby, if stable enough Encourage parents to touch & stroke their baby Point out nice features of baby Do not focus solely on child’s illness Allow parents to participate in care Listen to parents grieve & support them
Kangaroo Care holding a diaper-clad infant in skin-to-skin contact, prone and upright on the chest of the parent. • Infant enclosed in parent’s clothing to maintain temperature stability. Recommended for • Medically stable infants • Infants receiving palliative care • http: //www. adhb. govt. nz/newborn/Guidelines/Developmental/Kangaroo. Care. htm
Complications of Congenital Heart Defects n Bacterial Endocarditis n Pulmonary Hypertension n Congestive Heart Failure n Arrythmias n Emboli
Bacterial Endocarditis. n When blood is pumped at high pressure through defects, the lining of the heart tissue will become irritated and inflamed n Bacteria in the bloodstream can easily infect this injured area, causing a serious illness known as bacterial endocarditis
“SBE Prophylaxis” (Subacute Bacterial Endocarditis) http: //www. americanheart. org/presenter. jhtml? identifier=11086
“SBE Prophylaxis” indicated for: n All cyanotic heart lesions, especially those with systemicto-pulmonary shunts in place n All post-operative coarctation patients, whether surgically repaired or after balloon dilation n All those with valvar abnormalities, whether congenital, rheumatic, or with prosthetic valve in place n VSD patients: the more smaller the VSD, the higher the chance of SBE http: //nips. med-web. com/Handouts/Individual%20 Pages/Jenny's%20 Handouts/j-sbe. htm
Pulmonary Hypertension n Large volumes of blood pumped to the lungs → high pressure n Blood vessels in the lungs become damaged by the extra pressure n Pressure builds up in the lungs → ↓ blood flow from the left heart to the right heart (preserves lung function) n Blood flow in the heart goes from areas of high pressure to areas of lower pressure
Pulmonary Hypertension and “Shunting” right to left n If defects causing high blood flow to lungs persist, lung disease will develop n Pressure in the right heart will become higher than in the left heart n Oxygen-poor blood will flow from the right side of the heart (via ASD/VSD/PDA) into the left side (and out to the body)
Pulmonary Hypertension and “Shunting” right to left When there is an opening or passage between the atria, ventricles, and/or great vessels … and … Right heart pressure is higher than left heart pressure
Congestive Heart Failure n Right-sided failure if difficult to pump blood to pulmonary artery Ø↑pressure develops in right atrium & systemic venous circulation Ø→ hepatosplenomegaly & edema
Congestive Heart Failure n Caused by conditions that require the heart muscle to work hard n Failure of one side of heart leads to failure of the other side due to reciprocal changes n Presenting symptoms may vary ØImpaired myocardial function ØPulmonary congestion ØSystemic venous congestion
Congestive Heart Failure n Tachypnea n Tachycardia (at rest) n Dyspnea n Retractions n Activity Intolerance (poor feeding) n Enlarged liver n Enlarged heart on CXR (& on EKG) n ↑pulmonary blood flow on CXR
Congestive Heart Failure Treatment Goals (Wong 9 th ed. p 836) n ↓ afterload by vasodilation (ACE inhibitors) n ↑ cardiac contractility (glycoside: Lanoxin) n ↓ preload by removing excess fluid & sodium (diuretics: Lasix & thiazides) n ↓ cardiac demands (rest & homeostasis) n Improve tissue oxygenation & ↓ oxygen consumption (O 2 administration)
Heart Failure & Failure to Thrive n Poor weight gain n Expends too much energy & calories trying to breathe & eat n Feedings should be appropriate to child’s developmental stage n Wong 9 th ed. p 391 n Wong 9 th ed. p 840
Oral medication administration
How to Give Oral Medication to an Infant Aim the medicine toward the back near the gums or cheeks, but not at the back of the tongue. Squirt medicine into the mouth in small amounts. or Place a clean nipple into the baby's mouth and then put the medicine into the nipple and let the baby suck the medicine through the nipple. http: //www. ehow. com/how_2068060_give-baby-medicine. html Also, look in Wong p. 718 -719 re: oral medication administration for infants.
Break Time!!
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