RNC cardiac review

Elizabeth Rex, MS, NNP-BC NCC Cardiac Content

♥ Congestive Failure ♥ Transition to extrauterine life ♥ Hypertension ♥ PDA ♥ ♥ CV Assessment BP CVP ♥ EKG Monitoring ♥ Anomalies (Cyanotic / Acyanotic) Lines AV Canal ♥ Cyanosis Coarctation of aorta Central / Peripheral HLHS Cardiac / Pulmonary Pulmonary stenosis/atresia TOF ♥ Arrhythmias TGA TAPVR Fetal Circulation

3 fetal shunts Ductus venosus Foreman ovale Ductus arteriosus Cardiovascular Transition

♥ 10 min = PaO2 50 mm hg ♥ 1 hr = PaO2 62 mm hg ♥ 2 days PaO2 75-85 mm hg

24 hours after birth: ♥ Oxygen consumption triples ♥ Significant increase in ♥ Left must remodel and hypertrophy Respiratory Assessment

♥ Normal Rate: 30-60, easy effort

♥ Increased WOB: tachypnea, GFR, gasping

♥ Saturations: Pre and post Assessment

♥ Normal rate 120-160 (may range 80-200)

♥ Normal sinus rhythm

Underlying causes ♥ ↑ Vagal tone ♥ Apnea ♥ Hypoxemia ♥ Asphyxia ♥ Hypotension ♥ Acidosis ♥ Digoxin toxicity ♥ Central line in right atrium

Evaluate for shock ♥ HR < 70 is usually pathologic ♥ Differentiate Sinus bradycardia - QRS complex follows each p wave ♥ Complete heart block Complete Heart Block

♥ Ventricular rate 45-89 beats/min

♥ P wave unrelated to QRS

♥ Increased incidence with maternal lupus erythematosus

♥ If hydroptic at birth, will be critically ill

♥ Abnormal tachycardia sustained HR>180 - Assess for shock, CHF - Evaluate resp status, , , BP

♥ Most common: sustained HR 180-220 Sympathetic stimulation Fever SVT Supraventricular Tachycardia

Sustained HR > 220 ♥ Usually well tolerated initially unless associated with:

Structural CHD

Hydrops SVT

- 15 lead EKG - Run while doing tx - Vagal maneuvers - Stimulate a gag - Suction nasopharynx - Ice to nose and forehead - Adenosine - Initial dose 100 mcg/kg - Rapid IV push over 1-2 seconds followed by flush - No response in 2 minutes increase dose 50-100 mcg/kg - Cardiover sion - 0.5 joules/kg Heart

♥ First heart sound – S1 Closure of mitral and tricuspid valves End of atrial Heard best 5 th intercostal space @ left midclavicular line or LLSB

♥ Second heart sound – S2 Closure of aortic and pulmonic valves End of ventricular systole Heard best ULSB, called pulmonic valve area

Sound caused by turbulent blood flow

♥ Blood forced through narrowed areas

♥ Regurgitation through incompetent or abnormal valves

♥ Increased flow across normal structures Heart Auscultation

Murmurs ò Location ò Transmission ò Intensity ò Timing ò Quality ò Grading I - VI Heart Murmur Intensity

Grade I - barely audible Grade II - soft but audible Grade III - moderately loud, no thrill Grade IV - loud, assoc. with thrill Grade V - audible with stethoscope barely touching chest Grade VI - audible with stethoscope not touching chest Heart Murmur Timing

♥ Systolic ò Heard between S1 and S2 of same beat S1 (murmur) S2 S1 (murmur) S2

♥ Diastolic ò Heard between S2 and S1 of next beat S1, S2 (murmur) S1, S2 (murmur)

♥ Continuous ò Starts in systole and extends into Normal Murmurs

♥ Peripheral pulmonic stenosis PPS Grade I-II/VI upper left sternal border, radiates to axilla and back

♥ Systolic ejection/ continuous Grade I-II/VI may be heard 1 st week of life as PVR decreases and PDA closes

♥ Flow murmur Grade I-III/VI associated with anemia Pathologic Heart Murmur ♥ > Grade 3 murmur within hours of birth

♥ Pan systolic murmur Mitral or tricuspid regurgitation Severe pulmonary disease Asphyxial injury of tricuspid valve

♥ Diastolic murmur Aortic or pulmonic valve regurgitation

♥ Continuous murmur PDA, AVM, aortopulmonary window Pathologic Heart Murmur

♥ Central cyanosis ♥ Respiratory distress ♥ Abnormal heart silhouette ♥ ↑ or ↓ pulmonary vascularity on CXR ♥ Gallop ò CHF Assessment - Palpation

♥ Skin: color, temperature, diaphoresis, edema

♥ Precordium: quiet, visible, heave, thrill PMI - LLSB 5 th intercostal space PMI shifted to the right: Dextrocardia Tension pneumothorax Diaphragmatic hernia

PMI shifted to the left Tension right pneumothorax Assessment - Palpation

♥ Pulses: compare upper to lower extremities and side to side ò Brachial and femoral equal in strength ò Pedal pulses palpable ò Concern if weak, thready, bounding

♥ CFT: press for 5 seconds, release < 3 seconds normal

♥ Liver: below right costal margin < 2 cm preterm < 3 cm term Assessment Auscultation

Bruits ♥ Liver ♥ Anterior fontanelle ♥ May indicate AVM arteriovenous malformation Assessment Auscultation

♥ First heart sound – S1

ò Closure of the tricuspid and mitral

ò End of atrial systole

ò Heard best at the 5 th intercostal space at the left midclavicular line or LLSB Assessment Auscultation

♥ Second heart sound – S2 ò Closure of aortic and pulmonic valves

ò End of ventricular systole

ò Heard best • ULSB • Pulmonic valve area Assessment Auscultation

Single S2 - Normal in first few days of life with ↑ pulmonary

♥ Splitting of S2 difficult to hear with tachycardia

♥ Absence of either aortic or pulmonic S2: ò Severe aortic stenosis or atresia ò Severe pulmonary stenosis or atresia ò Truncus arteriosus ò PPHN ò Transposition of the great ò Tetralogy of Fallot Cyanosis - Peripheral

♥ Acrocyanosis ò Bluish discoloration hands and feet ò No mucous membrane involvement ò Often resolves by 48 hours of age ò Rule out hypothermia Cyanosis - Peripheral

♥ Circumoral cyanosis ò Bluish discoloration around the mouth ò Often associated with feeding ò R/O central cyanosis Cyanosis - Central

♥ Bluish discoloration of tongue and mucous membranes

♥ Caused by desaturation of arterial blood Hemoglobin carrying no O2 appears purple = reduced hemoglobin

♥ Cyanosis may be visible with 3-5 grams of reduced hemoglobin

♥ Indicates cardiac or respiratory dysfunction Cyanosis - Pulmonary / Cardiac

Pulmonary Cardiac Cyanosis Yes Yes Respiratory Rate Increased Increased – often tachypneic no GFR Infant looks comfortable if no CHF Work of breathing Increased Easy effort unless CHF – then GFR Acid/Base Balance Increased PCO2 Decreased PCO2 with tachypnea Respiratory acidosis Metabolic acidosis Mixed resp/metabolic if pulmonary disease CXR Asymmetric pattern of Increased or decreased infiltrates or other pulmonary vasculature pulmonary disease Heart silhouette normal abnormal Size/shape/location O2 Challenge test PO2> 150 PO2 < 150 for cyanotic CHD Blood pressure

Methods for measuring

Arterial:

♥ Umbilical

♥ PAL Radial

♥ PAL Posterior tibialis Hypertension

♥ Systolic or mean arterial BP > 95 th percentile for birth weight, gest age, and post-natal age

95 th percentile for systolic BP = 65 mmHg at 24 wks.

95 th percentile for systolic BP = 90 mmHg at 40 wks post conception. Hypertension Treatment

♥ Varies with cause of hypertension

♥ Tx etiology if possible

♥ Anti-hypertensive only if hypertension immediately life threatening CVP

♥ In most cases the trend in CVP is more helpful than absolute value

♥ CVP may be difficult to interpret because it is affected by several factors: ò hypervolemia ò myocardial failure ò excessive ventilatory pressures ò grunting respirations ò tension pneumothorax ò pleural effusion ò UVC tip in portal system Systole & Diastole

Adult

Systole is contraction of the ventricles

Diastole is the relaxation and filling of the ventricles followed by a small atrial contraction Cardiac Cycle

average neonate’s cardiac cycle is ≈ 0.4 secs, based on a HR of 150

Supraventricular tachycardia HR 230 60 ÷ 230 = 0.26 secs HR 300 60 ÷ 300 = 0.2 secs Cardiac Output The volume of blood pumped by the left ventricle in 1 min 120 -200 ml/kg/min

CO = x HR Cardiac Output

Influenced by changes in HR, pulmonary vascular resistance, and systemic vascular resistance to flow

Also influenced by the amount of blood returning to the heart Stroke Volume Relatively fixed at 1.5 ml/kg

Factors that affect SV

♥

♥

♥ Contractility Preload

The volume of blood in the ventricle before contraction

Dependent upon venous return to the heart

An ↑↓ in preload can significantly affect CO in the neonate’s non compliant heart

Clinically, a measure of pressure rather than volume Preload Changes

↓ ♥ Intrapartum blood loss ♥ ♥ Peripheral pooling secondary to bacterial sepsis

↑ ♥ Fluid overload ♥ Left to right shunt thru PDA, VSD, PFO Contractility

Speed of ventricular contraction - Intrinsic pumping ability

Neonate’s heart has a limited capacity to increase contractility

Cannot be clinically measured Contractility

Decreased by: Acidosis Hypoxia Hypocalcemia Hypoglycemia Hypercarbia Myocarditis Resistance to blood leaving the ventricles

Dependent on the systemic vascular resistance and pulmonary vascular resistance

After-load can be reduced by IV infusions of vasodilators Cardiovascular function is modulated by the autonomic nervous system Baroreceptors

Baroreceptors and chemoreceptors in the aorta and carotid sinuses provide feedback to the autonomic nervous system The parasympathetic or sympathetic nervous systems are then stimulated Sympathetic stimulation through the ganglionic chain releases norepinephrine and epinephrine which act on the SA node, the AV node, the atria and the ventricles. Alpha- and beta-adrenergic receptor stimulation alpha - ↑ contractility and ↑ rate beta – vasodilatation, bronchodilation, and smooth muscle relaxation Congestive

♥ Myocardial dysfunction in which the heart is unable to pump enough blood to meet its needs, to dispose of venous return adequately, or a combination of the two

♥ May result from CHD or acquired heart diseases with volume or pressure overload or from myocardial insufficiency Potential Causes

♥ Structural cardiac defects ♥ Hypoglycemia ♥ Cardiomyopathy ♥ Hypocalcemia ♥ Cardiac arrhythmias ♥ Severe anemia ♥ AV malformations ♥ Polycythemia ♥ Multiple hemangiomas ♥ Fluid overload ♥ Asphyxia ♥ Renal Failure ♥ Bronchopulmonary dysplasia ♥ Adrenal insufficiency ♥ CHF - fetal causes

♥ SVT Presentation: ♥ Severe bradycardia d/t Hydrops complete heart block ♥ Anemia Treatment: ♥ Ebstein’s anomaly Digoxin ♥ Myocarditis CHF - occurring the first day of life

♥ Asphyxia

♥ Hypoglycemia

♥ Hypocalcemia

♥ Sepsis CHF - occurring the first week of life

♥ PDA

♥ Adrenal Insufficiency

♥ Closure of PDA with ductal dependent lesion: Coarctation of the aorta Hypoplastic left heart syndrome Interrupted aortic arch CHF - occurring beyond the second week of life

♥ VSD most common reason

♥ Truncus arteriosus CHF –pulmonary presentation

♥ Poor weight gain ♥ Poor feeding of recent onset ♥ Feeding intolerance ♥ Tachypnea, dyspnea that worsens during feeding ♥ Increased WOB: Grunting, flaring, and retracting Head bobbing ♥ Rales, rhonchi, wheezing ♥ Irritability, lethargy ♥ Pulmonary infiltrates on CXR Pulmonary venous engorgement

Cause is blood backing up in the pulmonary system Leakage of fluid into the pulmonary interstitium

• Interferes with gas exchange

• LV dysfunction &/or overload may increase LV end diastolic pressure CHF – CV presentation ♥ Cold sweat on forehead - diaphoresis ♥ Puffy eyelids, dependent edema ♥ Pallor, mottling, cyanosis ♥ Increased precordial activity ♥ Peripheral pulses initially full but decrease in end stage, prolonged CFT ♥ Tachycardia, gallop rhythm, BP changes ♥ Decrease in urine output (<0.5 ml/kg/hr), increase in specific gravity ♥ Sudden weight gain in end stages ♥ Hepatomegaly ♥ Cardiomegaly on CXR Systemic venous engorgement

Blood backing up in the systemic system

Leakage of fluid into the periphery interstitium and liver

Hepatomegaly

RV dysfunction &/or overload my increase RV end diastolic pressure CHF – SNS compensatory mechanisms

↓ Systemic BP activates baroreceptors

↑ sympathetic stimulation

♥ ↑ HR

♥ ↑ cardiac contractility

♥ ↑ arterial BP CHF – SNS compensatory mechanisms Catecholamine release ↑ venous tone ↑ blood return to the heart

↓ circulation to skin, kidneys, extremities, & splanchnic bed

↓ Renal blood flow stimulates release of renin angiotensin, and aldosterone

which triggers retention of Na and fluid, resulting in increased circulating blood volume

↑ Blood volume puts additional work load on the heart CHF – mechanical compensatory mechanisms

Cardiac muscle thickens to ↑ myocardial pressure

Hypertrophy effective in early stages as muscle mass ↑ compliance ↓

↓ compliance requires ↑ filling pressure for CO CHF – mechanical compensatory mechanisms

Hypertrophied heart eventually becomes ischemic

Ventricular dilation occurs to accommodate volume

Initially the heart tries an increased force of contraction but soon fails CHF - management

♥ Elimination of underlying causes

♥ Elimination of precipitating causes

♥ Treatment: ò fluid restriction ò supportive care with supplemental FiO2 ò limiting PO feeding ò increased calorie feedings ò diuretics ò inotropic/ agents ò afterload-reducing agents Medications for CHF

Diuretics: Furosemide (Lasix) Spironolactone (Aldactone)

Digoxin: positive inotropic ↑ cardiac contractility negative chronotropic ↓ HR Shock

♥ An acute state in which circulatory function is inadequate to supply sufficient amounts of O2 and nutrients to meet metabolic demands

♥ In most cases, cardiac output is low

♥ In early shock, compensatory regional may temporarily maintain normal BP Hypotension

♥ Late sign - cardiac decompensation

♥ Treatment of shock based on more than BP: Evaluate history

Physical exam

Labs Shock

♥ As shock progresses, compensatory mechanisms fail and there is widespread cellular damage

♥ Insufficient delivery of O2 results in anaerobic metabolism and lactic acidosis. Shock

♥ If shock persists, irreversible injury to vital organs occurs, death ensues despite vigorous treatment that may temporarily return cardiovascular measurements to normal Shock Etiology

♥ Hypovolemia

♥ Asphyxia

♥ Cardiogenic causes

♥ Sepsis

♥ Drugs Hypovolemia

Blood loss

Inadequate placenta transfusion

Feto-maternal transfusion

Severe dehydration Asphyxia

Antepartum

Intrapartum

Respiratory failure

Impaired O2 transport due to severe anemia or hemoglobinopathy Cardiogenic Cardiomyopathy

Dysrhythmias

Congenital malformation

Hypocalcemia

Severe hypoglycemia Sepsis

Especially early onset group B beta-hemolytic Streptococcal Drugs

Hypovolemic infants whose BP has been maintained by vasoconstriction and are given vasodilators

PGE1 isoproterenol magnesium Shock Presentation Cardiovascular

ò Systemic arterial hypotension

ò Narrow pressure

ò Central venous hypotension, although CVP may be elevated with cardiomyopathy

ò Tachycardia Shock Presentation

Respiratory Other signs

ò Tachypnea ò Prolonged ò Retractions capillary fill time ò Grunting ò Oliguria ò Apnea ò Hypothermia ò Metabolic acidemia Cardiac Tamponade – a medical emergency

♥ The hemodynamic result of fluid accumulation in the potential space surrounding the heart or .

♥ Excessive fluid accumulation results in ↑ pericardial pressure, causing ↓ ventricular filling, ↓ cardiac output and hypotension.

♥ The rapidity of fluid accumulation influences the hemodynamic effect.

♥ Beck’s triad (jugular venous distension, hypotension, and muffled ). PICC

cardiac tamponade Congenital Heart Disease

Increased Pulmonary Flow: PDA - Patent Ductus Arteriosus VSD – Ventricular septal defect AV Canal – Endocardial Cushion partial or complete 30% are infant’s with trisomy 21 ASD – Atrial Septal Defect Congenital Heart Disease

Ductal dependent lesions that decrease pulmonary blood flow:

TOF - Tetralogy of Fallot with severe PS or PA PA - Pulmonary Atresia PS - Pulmonary Stenosis TA - Tricuspid Atresia Congenital Heart Disease

Mixed lesions: TGA -Transposition of the great arteries

TAPVR - Total anomalous pulmonary venous return

HLHS - Hypoplastic left heart syndrome

TA -Truncus arteriosus Ductal Dependent Defects

♥ Need to have PDA open for systemic or pulmonary circulation

♥ PGE1 continuous infusion to open and maintain ductal patency EKG cardiac depolarization is the result of an electrical discharge across the myocardial cell cardiac depolarization is measured by the EKG reflects abnormal hemodynamic burdens placed on the heart right ventricular prominence normal after birth major tool to evaluate arrhythmias and the impact of electrical imbalances Echocardiogram

The Gold Standard

Provides rapid, non-invasive, and painless evaluation of the ♥ anatomy and flow by the use of ultrasonic waves Cardiac Catheterization

♥ Invasive procedure to obtain data for a definitive diagnosis, intervene, or to prepare for surgery

♥ Diagnostic Evaluate Selective angiography

♥ Interventional Balloon atrial septostomy (Rashkind) Balloon valvuloplasty Balloon angioplasty PDA

Shunts right to left flow in utero

Persistent PDA will shunt left to right as PVR decreases

Functional closure - constricted but can open again

Anatomic closure – permanently closed

PGE used to open PDA: If you need left to right flow for pulmonary perfusion If you need right to left flow for systemic perfusion erex Self Study the following Congenital Heart Defects AV Canal

♥ Endocardial Cushion Defect or Atrioventricular Septal Defect

♥ Partial involves the atria

♥ Complete involves atria and ventricles AV canal Risk Factors

Trisomy 21 Rubella or other viral illness during early pregnancy Alcohol consumption Poorly controlled diabetes Smoking Parent with a CHD AV canal complications

♥ Cardiomegaly

♥ Pulmonary Hypertension

♥ Respiratory Tract Infections

♥ Congestive Heart Failure Complications after correction of AV canal

♥ Regurgitant heart valves

♥ Stenosis of the heart valves

♥ Arrythmias

♥ PPHN

♥ Breathing difficulties associated with lung damage COA – Coarctation of the aorta

♥ Juxtaductal narrowing of aorta

♥ Frequently associated bicuspid aortic valve

♥ Often associated with hypoplastic transverse arch

♥ Mild left heart hypoplasia COA - Coarctation of the aorta

♥ As the ductus arteriosus closes the area of coarctation narrows

♥ The result is decreased systemic blood flow

♥ In severe cases, CHF results from decreased left ventricular function

With ducal closure shock and tissue hypoxia HLHS – hypoplastic left heart syndrome

♥ Hypoplasia of left ventricle

♥ Severe mitral valve stenosis or atresia or severe aortic valve stenosis or atresia

♥ Hypoplastic ascending aorta and transverse arch

♥ Coarctation is a frequent finding HLHS Ductal dependent blood flow right to left to perfuse all regions of the body Management: COA & HLHS

♥ To open PDA and to improve systemic perfusion

♥ Intubation and ventilation to reduce work of breathing and strain on the heart

♥ Avoid hyperoxia and hypocarbia (both will decrease PVR at the expense of systemic blood flow)

♥ Inotropic support may improve myocardial function

♥ Follow arm and leg BPs TOF – Tetralogy of Fallot

♥ 4 anomalies ò Large VSD ò Right ventricular outflow tract obstruction ò Overriding aorta ò Right ventricular hypertrophy

♥ Symptom severity depends on the degree of right ventricular outflow tract obstruction TOF TOF - Management

♥ Supplemental FiO2 to treat cyanosis

♥ The majority are not ductal dependent

♥ If saturation still below 75% on oxygen may have significant pulmonary stenosis or atresia and need PGE TET Spell Hypoxic Spell

♥ Cyanotic or hypercyanotic spell ò Progressive hypoxia ò Hyperpneic ò Pale, flaccid ò Immediate treatment needed ò Organ damage if severe hypoxia and acidosis ò Eventual loss of consciousness

TET Spell Management

Calm infant Increase systemic vascular resistance to decrease the right to left shunt at the VSD Knees to chest May need to be sedated FiO2 but will only improve oxygenation once right to left shunt is decreased May need intubation and correction of metabolic acidosis Pulmonary stenosis/atresia

♥ Stenosis is a narrowing

♥ Atresia means not formed, so absence PS Pulmonary Stenosis

♥ Varying degrees of pulmonary valve narrowing

♥ If critical PS the right ventricle cannot eject sufficient blood flow to the to maintain normal oxygen saturations.

♥ If critical PGE is required to allow blood to shunt left to right to perfuse the lungs

♥ A newborn with critical pulmonary stenosis and intact VSD presents an emergency situation that requires immediate treatment, either balloon dilation of the valve or surgery. PS Presents with varying degrees of cyanosis after birth PA Pulmonary Atresia with intact ventricular septum

♥ Atretic pulmonary valve ♥ Hypertrophied right ventricle ♥ Hypoplastic right ventricle

♥ Pulmonary blood flow is dependent on the PDA TGA – Transposition of the Great Arteries Great arteries are transposed relative to the ventricles TGA

♥ Circulation pattern is parallel ♥ The majority of the blood from each ventricle is circulated back to the same ventricle ♥ Mixing must occur: Best to have a VSD and a PFO/ASD that is not restrictive Use PGE to open the PDA ♥ If no VSD and a restrictive PFO/ASD a Rashkind/Balloon septostomy may be needed

There needs to be adequate mixing at 2 sites! TAPVR – Total Anomalous Pulmonary Venous Return TAPVR Types

♥ Supracardiac emptying into the left vertical (most common type 80-90%) which then drains into the SVC

♥ Cardiac emptying into the coronary sinus or right atrium

♥ Infradiaphragmatic emptying into the vertical vein that descends through the diaphragm into the portal vein or IVC Infracardiac Obstructed TAPVR

♥ Oxygenated pulmonary blood mixes with deoxygenated systemic blood and returns to the right atrium to shunt right to left across the PFO/ASD to get to the left atrium and eventually to the body

♥ Severe hypoxia and profoundly ill after birth Management Infracardiac Obstructed TAPVR

- Intubation 100% FiO2

- Treat acid /base disturbance

- Treat hypotension, hypothermia

- Emergency corrective surgery is required to anastomose the pulmonary to the heart CXR Cardiac or supracardiac CXR Obstructed TAPVR CXR can be confused with RDS or PNA