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RNC cardiac reviewElizabeth Rex, MS, NNP-BC
NCC Cardiac Content
♥ Transition to extrauterine life
♥ PDA
♥ CV AssessmentBPCVPEKGMonitoring Lines
♥ Cyanosis Central / PeripheralCardiac / Pulmonary
♥ Arrhythmias
♥ Congestive Heart Failure
♥ Hypertension
♥ Shock
♥ Cardiac Tamponade
♥ Anomalies (Cyanotic / Acyanotic)AV CanalCoarctation of aortaHLHSPulmonary stenosis/atresiaTOFTGA TAPVR
Fetal Circulation
3 fetal shuntsDuctus venosus Foreman ovaleDuctus 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 cardiac output♥ Left ventricle must remodel and hypertrophy
Respiratory Assessment
♥ Normal Rate: 30-60, easy effort
♥ Increased WOB: tachypnea, GFR, gasping
♥ Saturations: Pre and post
Heart Rate Assessment
♥ Normal rate 120-160 (may range 80-200)
♥ Normal sinus rhythm
Bradycardia
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
Tachycardia
♥ Abnormal tachycardia sustained HR>180- Assess for shock, CHF- Evaluate resp status, perfusion, pulses, BP
♥ Most common:Sinus tachycardia sustained HR 180-220Sympathetic stimulationFever
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
- Cardioversion- 0.5 joules/kg
Heart Auscultation
♥ First heart sound – S1Closure of mitral and tricuspid valvesEnd of atrial systoleHeard best 5th intercostal space @ left midclavicular line or LLSB
♥ Second heart sound – S2Closure of aortic and pulmonic valvesEnd of ventricular systoleHeard best ULSB, called pulmonic valve area
Heart Murmur
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� Location� Transmission� Intensity� Timing� Quality� Grading I - VI
Heart Murmur Intensity
Grade I - barely audibleGrade II - soft but audibleGrade III - moderately loud, no thrillGrade IV - loud, assoc. with thrillGrade V - audible with stethoscope barely
touching chestGrade VI - audible with stethoscope not
touching chest
Heart Murmur Timing
♥ Systolic� Heard between S1 and S2 of same beatS1 (murmur) S2 S1 (murmur) S2
♥ Diastolic� Heard between S2 and S1 of next beatS1, S2 (murmur) S1, S2 (murmur)
♥ Continuous� Starts in systole and extends into diastole
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 1st week of life as PVR decreases and PDA closes
♥ Flow murmurGrade I-III/VI associated with anemia
Pathologic Heart Murmur♥ > Grade 3 murmur within hours of birth
♥ Pan systolic murmurMitral or tricuspid regurgitationSevere pulmonary diseaseAsphyxial injury of tricuspid valve
♥ Diastolic murmurAortic or pulmonic valve regurgitation
♥ Continuous murmurPDA, AVM, aortopulmonary window
Pathologic Heart Murmur
♥ Central cyanosis♥ Respiratory distress♥ Abnormal heart silhouette♥ ↑ or ↓ pulmonary vascularity on CXR ♥ Gallop
� CHF
Assessment - Palpation
♥ Skin: color, temperature, diaphoresis, edema
♥ Precordium: quiet, visible, heave, thrill PMI - LLSB 5th intercostal space
PMI shifted to the right:DextrocardiaTension pneumothoraxDiaphragmatic hernia
PMI shifted to the leftTension right pneumothorax
Assessment - Palpation
♥ Pulses: compare upper to lower extremities and side to side
� Brachial and femoral equal in strength� Pedal pulses palpable� 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
� Closure of the tricuspid and mitral
� End of atrial systole
� Heard best at the 5th intercostal space at the left midclavicular line or LLSB
Assessment Auscultation
♥ Second heart sound – S2� Closure of aortic and pulmonic valves
� End of ventricular systole
� Heard best • ULSB• Pulmonic valve area
Assessment Auscultation
Single S2 - Normal in first few days of life with ↑ pulmonary vascular resistance
♥ Splitting of S2 difficult to hear with tachycardia
♥ Absence of either aortic or pulmonic S2:� Severe aortic stenosis or atresia� Severe pulmonary stenosis or atresia� Truncus arteriosus� PPHN� Transposition of the great arteries� Tetralogy of Fallot
Cyanosis - Peripheral
♥ Acrocyanosis� Bluish discoloration hands and feet� No mucous membrane involvement� Often resolves by 48 hours of age� Rule out hypothermia
Cyanosis - Peripheral
♥ Circumoral cyanosis� Bluish discoloration around the mouth� Often associated with feeding� 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 tachypneaRespiratory acidosis Metabolic acidosis
Mixed resp/metabolic if pulmonarydisease
CXR Asymmetric pattern of Increased or decreasedinfiltrates 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 artery
♥ PAL Radial
♥ PAL Posterior tibialis
Hypertension
♥ Systolic or mean arterial BP > 95th percentile for birth weight, gest age, and post-natal age
95th percentile for systolic BP = 65 mmHg at 24 wks.
95th 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:� hypervolemia� myocardial failure� excessive ventilatory pressures� grunting respirations� tension pneumothorax� pleural effusion� UVC tip in portal system
Cardiac CycleSystole & Diastole
Systole is contraction of the ventricles
Diastole is the relaxation and filling of the ventricles followed by a small atrial contraction
Adult
Cardiac Cycle
average neonate’s cardiac cycle is≈ 0.4 secs, based on a HR of 150
Supraventricular tachycardiaHR 230 60 ÷ 230 = 0.26 secsHR 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 = stroke volume 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
♥ Preload
♥ Afterload
♥ Contractility
Preload
The volume of blood in the ventricle beforecontraction
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
♥ Hypovolemia ♥ 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 limitedcapacity to increase contractility
Cannot be clinically measured
Contractility
Decreased by:AcidosisHypoxiaHypocalcemiaHypoglycemiaHypercarbiaMyocarditis
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 ↑ ratebeta – vasodilatation, bronchodilation, and smooth muscle relaxation
Congestive Heart Failure
♥ 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♥ Cardiomyopathy♥ Cardiac arrhythmias♥ AV malformations♥ Multiple hemangiomas♥ Asphyxia♥ Bronchopulmonary dysplasia
♥ Hypoglycemia♥ Hypocalcemia♥ Severe anemia♥ Polycythemia♥ Fluid overload♥ Renal Failure♥ Adrenal insufficiency♥ Hyperthyroidism
CHF - fetal causes
♥ SVT♥ Severe bradycardia d/t complete heart block♥ Anemia♥ Ebstein’s anomaly♥ Myocarditis
Presentation:Hydrops
Treatment:Digoxin
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 syndromeInterrupted 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 retractingHead 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:� fluid restriction� supportive care with supplemental FiO2� limiting PO feeding� increased calorie feedings� diuretics� inotropic/chronotropic agents� 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 vasoconstriction 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 severeanemia 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
PGE1isoproterenolmagnesium
Shock Presentation
Cardiovascular
� Systemic arterial hypotension
� Narrow pulse pressure
� Central venous hypotension, althoughCVP may be elevated with cardiomyopathy
� Tachycardia
Shock Presentation
Respiratory
� Tachypnea� Retractions� Grunting� Apnea
Other signs
� Prolonged capillary fill time
� Oliguria� Hypothermia� Metabolic
acidemia
Cardiac Tamponade –a medical emergency
♥ The hemodynamic result of fluid accumulation in the potential space surrounding the heart or pericardium.
♥ 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 heart sounds).
PICC
cardiactamponade
Congenital Heart Disease
Increased Pulmonary Flow:PDA - Patent Ductus Arteriosus
VSD – Ventricular septal defectAV Canal – Endocardial Cushion
partial or complete30% 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 AtresiaPS - Pulmonary StenosisTA - 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
EKGcardiac 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
♥ DiagnosticEvaluate hemodynamicsSelective angiography
♥ InterventionalBalloon 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 perfusionIf 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 21Rubella or other viral illness during early pregnancyAlcohol consumptionPoorly controlled diabetesSmokingParent 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� Large VSD� Right ventricular outflow tract obstruction� Overriding aorta� 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� Progressive hypoxia� Hyperpneic� Pale, flaccid� Immediate treatment needed� Organ damage if severe hypoxia and acidosis� Eventual loss of consciousness
TET Spell Management
Calm infantIncrease systemic vascular resistance to decrease the right to left shunt at the VSDKnees to chestMay need to be sedatedFiO2 but will only improve oxygenation once right to left shunt is decreasedMay 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 pulmonary artery 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 VSDand a PFO/ASD that is not restrictiveUse 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 vein (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 veins to the heart
CXR Cardiac or supracardiac
CXR Obstructed TAPVRCXR can be confused with RDS or PNA