Neonatal heart diseases

Neonatal heart diseases

DRISYA.V.R.2nd year MSc Nursing

CONGENITAL HEART DISEASES

IncidenceCongenital heart defects are serious and common conditions that have significant impact on morbidity, mortality, and healthcare costs in children and adults.The most commonly reported incidence of congenital heart defects in the United States is between 4 and 10 per 1,000, clustering around 8 per 1,000 live births.

Continental variations in birth prevalence have been reported, from 6.9 per 1000 births in Europe to 9.3 per 1000 in Asia.An estimated minimum of 32,000 infants are expected to be affected each year in the United States. Of these, an approximate 25%, or 2.4 per 1,000 live births, require invasive treatment in the first year of life.

PrevalenceIt is estimated that the total number of adults living with congenital heart disease in the United States in 2000 was 800,000.In the United States, 1 in 150 adults are expected to have some form of congenital heart disease.The most common types of defects in children are (at a minimum) ventricular septal defects,620,000 people; ASD, 235,000 people; valvular pulmonary stenosis, 185,000 people; and patent ductus arteriosus, 173,000 people. The most common lesions seen in adults are ASD and TOF.

Mortality

Mortality related to congenital cardiovascular defects in 2011 was 3,189. Any-mention mortality related to congenital cardiovascular defects in 2009 was 5,051.In 2011, congenital cardiovascular defects were the most common cause of infant death resulting from birth defects; 26.6% of infants who died of a birth defect had a heart defect.The mortality rate attributable to congenital heart defects in the United States has continued to decline from 1979 to 1997 and from 1999 to 2006.

The 2011 death rate attributable to congenital cardiovascular defects was 1.0. Death rates were 1.1 for white males, 1.4 for black males, 0.9 for white females, and 1.2 for black females. Infant mortality rates ( 2:1 is a well-established indication, though many authors advocate 1.7:1 or even 1.5:1.AHA recommends a threshold Qp/Qs 1.5:1, but these guidelines exclude patients > 21 years of age.Canadian Cardiac Society recommends Qp/Qs >2:1, or >1.5:1 in the presence of reversible pulmonary hypertension.

ContraindicationAmerican and European practice guidelines: PVR> 8 Woods units precludes closure and Eisenmenger syndromePop-off valve: COPD with cor pulmonale Balloon occlusion :rise in PAP

Timing of surgeryIdeally: 3-5 yearsUsually before 25 yearsElderly: Improves morbidity and mortality

Median sternotomy with direct closure of small to moderate defect - Larger defects closed with autologous pericardium or syntethic patches like polyester polymer ( Dacron )or polytetrafluoroethylene ( PTFE )

Minimally invasive techniques with hemisternotomy and limited thoracotomy is to improve cosmetic outcome

Percutaneous Transcatheter Closure - via femoral vein - success is as good as 96% in good hands

Percutaneous ClosureAmplatzer Occlusion DeviceConsists of two round disks made of Nitinol (nickel + titanium) wire mesh linked together by a short connecting waist.

VENTRICULAR SEPTAL DEFECT

A ventricular septal defect (VSD) is a communication (or multiple communications) between the right and left ventricles.

Types

Based on anatomic types:Perimembraneous Sub pulmonary Muscular Atrioventricular canal

Based on Lesion SizeRestrictive VSD< 0.5 cm2 (Smaller than Ao valve orifice area)Small Left to Right shuntNormal RV output75% spontaneously close < 2yrsNon-restrictive VSD> 1.0 cm2 (Equal to or greater than to Ao valve orifice area)Equal RV and LV pressuresLarge hemodynamically significant L to R shuntRarely close spontaneously

Based on sizeLarge Moderate Small

CHEST X-RAYCardiomegaly : proportional to the volume overload.Mainly LV, LA and RV enlargement.Increased pulmonary blood flow, PAH.

Unless LA is significantly enlarged its difficult to differentiate from ASD.

RV may not be as enlarged as anticipated as it receives the shunt into its outflow tract.

Management Observation & follow up Small VSDsMedical management Medium sized VSD CCF- treat with diuretics & digitalis, ACEI failure precipitated by LRTI- Treat both 2-3 months follow up RV & PA pressures assessed Failure to thriveSurgical Large VSD

drugs digoxin 10-20mcg/kg per day furosemide 13mg/kg per day captopril 0.52mg/kg per day enalapril 0.1mg/kg per day

Indications of surgical intervention

Large VSD with pulmonary hypertension VSD with aortic regurgitation VSD with associated defects Failure of congestive cardiac failure to respond to medications

AORTO PULMONARY WINDOW

Aorto-Pulmonary window is an opening between the ascending aorta and the main pulmonary artery. There must be two distinct and separate semilunar valves before this diagnosis can be made.

Types

Type I Type II Type III

PATENT DUCTUS ARTERIOSUS

The ductus arteriosus is a communication between the pulmonary artery and the aortic arch distal to the left subclavian artery. Patent ductus arteriosus (PDA) is the failure of the fetal ductus arteriosus to close after birth.In normal term infants it closes spontaneously at 3-5days.

COARCTATION OF AORTA

Coarctation of the aorta is a narrowing in the aortic arch.

A congenital narrowing of upper descending thoracic aorta adjacent to the site of attachment of ductus arteriosus

A congenital narrowing of upper descending thoracic aorta adjacent to the site of attachment of ductus arteriosus

CLINICAL FEATURESINFANTDepends on patency of PDAShock and HFMetabolic disturbancesHypothermiaHypoglycemiaHypo perfusionRenal failure

ChildUpper extremity HTN

Widened pulse pressure

Variability in right and left arm pressures

Murmurs

OthersIntermittent claudication (due to a temporary inadequate supply of oxygen to the muscles of the leg)

Pain and weakness of legs and

Dyspnea on running

INVESTIGATIONX RAY rib notching ,3 sign , cardiomegaly

ECHOHigh parasternal, suprasternal long axis

Shelf within lumen of thoracic aorta

Color and pulse wave doppler to locate area

Continuous wave doppler to detect maximum flow velocity

ECGMRIBARIUM SWALLOWCARDIAC CATHETERISATION

AORTIC STENOSIS

Aortic Stenosis (AS) is a narrowing that obstructs blood flow from the left ventricle, leading to left ventricular hypertrophy and/or aortic insufficiency.

Types

ValvarSubaorticSupravalvar

INTERRUPTED AORTIC ARCH

Interrupted Aortic Arch (IAA) refers to the congenital absence of a portion of the aortic arch. There are three types of IAA, and they are labeled according to the site of the interruption.

Types

Type AType BType C

MANAGEMENTProstaglandinSurgical repair

TETROLOGY OF FALLOT

Tetrology of Fallot (TOF) is a congenital heart defect characterized by the association of four cardiac abnormalities; VSD, pulmonary stenosis, overriding of aorta and right ventricular hypertrophy.

PULMONARY STENOSIS

Pulmonary stenosis (PS) is a narrowing that obstructs blood flow from the right ventricle. It may be subvalvular, valvular, supravalvular or in the pulmonary arteries

CLINICAL FEATURESUsually asymptomatic and in normal health.Heart murmurCyanosis In an older child, severe pulmonary valve stenosis may cause easy fatigue or shortness of breath with physical exertion. Severe pulmonary valve stenosis rarely results in right ventricular failure or sudden death.

DIAGNOSISPresence of heart murmur.The heart murmur of pulmonary stenosis is a turbulent noise caused by ejection of blood through the obstructed valve.There is often an associated click sound when the thickened valve snaps to its open position. These sounds can be detected through careful examination of the heart by a physician well-trained in cardiac diagnosis.Theelectrocardiogramis typically normal in the presence of mild pulmonary stenosis. Theechocardiogramis the most important non-invasive test to detect and evaluate pulmonary valve stenosis. Cardiac catheterizationis an invasive technique that enables physicians to accurately measure the degree of pulmonary stenosis

TREATMENTMILD PULMONARY STENOSIS: Requires no surgical intervention. These infants and children are examined by cardiologists at regular intervals for signs of progression of the stenosis.

MODERATE TO SEVERE PULMONARY STENOSISPulmonary Balloon ValvuloplastySurgical Valvotomy

PULMONARY ATRESIA

Pulmonary Atresia with an Intact Ventricular Septum (PA with IVS) includes a spectrum of defects that can include disorders of the tricuspid valve, right ventricle and coronary circulation. The term atresia indicates failure of the pulmonary valve or pulmonary trunk vessel to develop; therefore there is no connection between the right ventricle and pulmonary artery.

Management

Prostaglandin infusion Oxygenmaintenance of acid-base balance

Surgery

PalliativeCorrective

TRICUSPID ATRESIA

Tricuspid atresia is the failure of development of the tricuspid valve, resulting in a lack of direct communication between the right atrium and the right ventricle. Incidence : 0.06 per 1000 live births

TYPES

MUSCULARMEMBRANEOUSVALVAR

Surgery

PalliativeReconstructive

EBSTEINS ANOMALY

Ebsteins anomaly is a rare congenital defect of the tricuspid valve. The tricuspid valve leaflets do not attach normally to the tricuspid valve annulus. The leaflets are dysplastic and the septal and posterior leaflets are downwardly displaced, adhering to the right ventricular septum.

PATHOPHYSIOLOGYATRESIA OF TRICUSPID VALVE

No communication between RA AND RV

RV id underdeveloped.Systemic venous blood received by RA

Enters LA through PFO or ASD

Mixing of systemic and pulmonary blood

Enters LV

Blood enters RV through VSD

From RV blood enters Pulm trunk

Blood enters pulm trunk via PDA

Increased pulmonary blood flow

LA and LV hypertrophy

CHF

CLINICAL FEATURESDECREASED PULM FLOW 90%severe cyanosis, hypoxemia, and acidosisLV apical impulseWaves in jugular venous pulsepulmonary oligemia may have central cyanosis, tachypnea or hyperpnea

INCREASED PULM FLOWmay not appear cyanotic but may present with signs of heart failure later in infancypulmonary plethora present with symptoms of dyspnea, fatigue, difficulty feeding, and perspiration, which are suggestive of congestive heart failure.Cyanosis is minimal

Other featuresholosystolic type of murmur at the lower sternal border, suggestive of VSD,Problems related to chronic cyanosis, such as clubbing, polycythemia, relative anemia, stroke, brain abscess, coagulation abnormalities,

INVESTIGATIONSHistory and PEPulse oximetryABGHb and hematocrit

MANAGEMENTan intravenous infusion of PGE1 0.03-0.1 mcg/kg/min to open the ductus arteriosusanticongestive therapy with digoxin, diuretics

Surgery

PalliativeTricuspid Valvuoplasty

TRANSPOSITION OF GREAT ARTERIES

Surgery

Rashkind Procedure (Palliative)Arterial Switch Procedure (Corrective)

DOUBLE OUTLET RIGHT VENTRICLE

Double Outlet Right Ventricle (DORV) spans a wide spectrum of physiology from Tetrology of Fallot to Transposition of the Great Arteries. DORV is a complex cardiac defect where both great vessels (aorta and pulmonary artery), either completely or nearly completely arise from the right ventricle

Types

a. DORV with subaortic VSD and without PS1. b. DORV with subaortic VSD and pulmonary stenosis2. DORV with subpulmonic VSD (Taussig-Bing anomaly)3. DORV with doubly committed VSD4. DORV with remote VSD

TREATMENT

TOTAL ANOMALOUS PULMONARY VENOUS RETURN

Total Anomalous Pulmonary Venous Return (T-APVR) results from the failure of the pulmonary veins to join normally to the left atrium during fetal cardiopulmonary development.

IncidenceTAPVC occurs in approximately 4-6 per 100,000 live births.This anomaly accounts for 1-3 percent of the cases of congenital heart disease

Types

SupracardiacCardiacInfradiaphramaticMixed

INVESTIGATIONSChest X-ray Figure of 8 or snow-man appearanceGround-glass appearance

ECGEchoCardiac catheterization

MANAGEMENTEmergency medical managementImmediate endotracheal intubation and hyperventilation with 100% oxygen to a PaCO2 of 30 mm Hg and correction of pH. Induced respiratory alkalosis decreases pulmonary vascular resistance and improves oxygenation.

Metabolic acidosis should be treated with NaHCO3 or Tromethamine (THAM) infusions.

Isoproterenol has special merit for inotropic support in obstructed TAPVC because it has pulmonary vasodilatory properties (0.1 microgm/kg/min for 24-48 hrs).

PGE1 infusion given to maintain patency of ductus venosus to decompress the pulmonary veins in obstructed TAPVC.

Surgery various approaches for surgery-Posterior approachRight atrial approach Superior approach

TRUNCUS ARTERIOSUS

Truncus arteriosus is a rare congenital heart defect in which a single great vessel arises from the heart, giving rise to the coronary, systemic and pulmonary arteries.

Types

Type IType IIType IIIType IV

HYPOLPLASTIC LEFT HEART SYNDROME

Hypoplastic Left Heart Syndrome (HLHS) is identified as a small, underdeveloped left ventricle usually with aortic and/or mitral valve atresia or stenosis and hypoplasia of the ascending aorta.

Surgery

Stage I NorwoodBi-directional GlennFontan

CONGESTIVE CARDIAC FAILURE

Congestive heart failure (CHF) is a term as the heart does not pump enough blood out to the rest of the body to meet the body's demand for energy.

TreatmentA diuretic likefurosemide(Lasix), which helps the kidneys to eliminate extra fluid in the lungs, is often the first medicine given both in babies and older children.Sometimes medicines to lower the blood pressure like an ACE inhibitor (Captopril), or more recently, beta blockers (Propranolol) are used. Theoretically, lowering the blood pressure will decrease the workload of the heart by decreasing the amount of pressure against which it has to pump.Sometimes a medication calledDigoxinis used to help make the heart squeeze better, and help pump blood more efficiently. Since weight gain is a major challenge for infants with congestive heart failure, giving babies high calorie formula or fortified breast milk can help give the extra nutrition they require.Sometimes babies will need to have extra nutrition given to them via a tube that goes directly from

The nose to the stomach, anasogastric feeding tube. This is good for babies who work hard or get very tired from feeding in order to prevent them from using up all the extra calories needed for growth. Older children with significant heart failure can also benefit from nasogastric feeding to give them more calories and energy to do their usual activities.Oxygen can worsen blood flow to the lungs in babies with large ventricular septal defects but may be helpful as a buffer to children with weak hearts.Some kids with cardiomyopathy may also need restriction of certain kinds of exercise and competitive sports, although they may benefit from light activity like swimming.

PERSISTENT PULMONARY HYPERTENSION

Persistent pulmonary hypertension (PPHN) has also been referred to as persistent fetal circulation, persistent pulmonary vascular obstruction, pulmonary vasospasm, neonatal pulmonary ischemia and persistent transitional circulation.

TypesPersistent pulmonary hypertension associated with pulmonary parenchymal diseasePersistent pulmonary hypertension with radiographically normal lungsPersistent pulmonary hypertension associated with hypoplasia of the lungs

CausesRepeated intrauterine closure of the ductus with redirection of blood flow into the high-resistance fetal pulmonary circulation. High dose aspirin ingestion by the mother and the administration of prostaglandin inhibitors have been cited by research to cause persistent pulmonary hypertension. Abnormal responsiveness of the pulmonary vasculature to hypoxia with an inability to relax after the stimulus for vasoconstriction is removed as in birth asphyxia. Repeated intrauterine hypoxia, which causes hypertrophy of pulmonary arteriole smooth muscle, which enables these vessels to extremely constrict for a long period of time.

Regional alveolar hypoxia due to poor ventilation that cannot be detected with a chest radiograph. In cases such as congenital diaphragmatic hernia or other causes of pulmonary hypoplasia, undergrowth of the pulmonary vascular structures. Alteration in vasoactive mediator levels may cause pulmonary vasoconstriction. These include nitric oxide, eicosanoids, endothelin, leukotrienes, platelet activating factor and tumor necrosis factor. Micro thrombi and released mediators have been reported in infants with persistent pulmonary hypertension.

Clinical conditions frequently associated with persistent pulmonary hypertension of the newborn

Meconium Aspiration Syndrome (MAS) Asphyxia Sepsis/infection Pneumonia (bacterial) Congenial Diaphragmatic Hernia (pulmonary hypoplasia) Transient Tachypnea of the Newborn (TTNB) Respiratory Distress Syndrome (RDS/HMD)

Polycythemia/ hyper viscosity Metabolic disturbances (hypoglycemia, hypocalcemia, hypomagnesemia) Hypothermia Systemic hypotension Prenatal fetal hypertension Congenital heart disease Hypoventilation resulting from asphyxia or other neurological conditions

Clinical picture May be entirely normal Term or post term infant (because the pulmonary arterial musculature does not develop until late gestation) Dysmaturity may exist Meconium staining Cyanosis (if this is the main sign/symptom, the clinician should rule out congenital heart and severe pulmonary parenchymal disease) Respiratory distress with tachypnea, but minimal retractions on day one.Right-to-left shunting

Breath sounds may be normal (If pneumonia or meconium staining exists, crackles or wheezes may be present) Heart sounds may be normal or a murmur may be heard Systemic hypotension later in course following heart failure and persistent hypoxemia. Sensitivity to handling Hyperdynamic precordium

Diagnosis Chest X-ray CBCSerum electrolytes Blood gases

TREATMENTAdminister oxygen High frequency ventilation Surfactant administration Continuous monitoring of pre and post-ductal PaO2 Alkalinizing agents Dopamine and Dobutamine

Prostaglandin I2 Magnesium sulfate, perflourocarbon liquid ventilation and arginine infusionECMO

CONGENITAL COMPLETE HEART BLOCK

Congenital complete heart block is the most common cardiac cause of fetal and neonatal bradycardia. It is a disorder of conduction due to abnormality in the AV node with total dissociation between atrial and ventricular contractions.

ManagementIsoproterenol to increase ventricular rateTransventricular cardiac pacingCaesarean section if FHR < 50 bpm or hydrops fetalisClose monitoringDigitalisDiureticsIntraventricular pacing if HR