MCN

• Cardiovascular issues in children


  Complex, spanning the spectrum from congenital defects that may present at birth to acquired heart disease or late-onset inherited disorders
• Risk management for CONGENITAL HEART DISEASE

  • Cause is idiopathic, but associations of CHD are seen with familial patterns of inheritance
  • Pregnant/entering pregnancy need to be fully immunized to prevent infection during pregnancy
  • Parents with a personal or family history of CHD need to be aware that other children born to them need to be carefully screened prenatally and at birth for a similar disorder
• Risk management for ACQUIRED HEART DISEASE


  • Know the cause
  • Risk Factors: Rheumatic fever - an autoimmune response that follows a group A beta-hemolytic streptococcal infection
• Management of Rheumatic fever

  Ensure that all children who have a streptococcal infection such as streptococcal pharyngitis receive adequate antibiotic therapy to prevent rheumatic fever
• Hypertension


  Elevated blood pressure
• Risk factors for hypertension

  • Genetic predisposition
  • High intake of sodium
  • Lack of exercise
  • Obesity
• Increase the chances that a susceptible child will develop hypertension by late childhood (Flynn et al., 2017)
• Management of hypertension


  1. Reduce intake of processed foods and snacks

  2. Monitor food intake

  3. Advocate more nutritious menus at schools
• Hyperlipidemia


  High cholesterol or too many lipids in the blood
• Causes of hyperlipidemia


  • Inherited
  • Diet high in saturated fat (school age and over)
• Infants & toddlers - no restriction of fat intake since it's needed for brain development
• School-aged children & adolescents (also adults) - reduced to 30% of total calories
• Management of hyperlipidemia


  1. Diet modification to low/no saturated fats

  2. Participate in routine aerobic physical activity with daily limits on screen time, including television, phone, computer, social media and/or games
• FETAL CIRCULATION


  PLACENTA
• Fetal circulation shunts


  • Foramen ovale - bypasses the lungs, blood from the RA to the LA
  • Ductus arteriosus - moves blood from the pulmonary artery to the aorta
  • Ductus venosus - bypasses the liver, highly oxygenated blood bypass the liver to the inferior vena cava & then to the RA of the heart
• Fetal circulation


  Blood from the RA flows to the LV, then to the aorta, blood is sent to the heart muscle itself and to the brain & arms, blood returns to RA thru SVC, blood enters the umbilical arteries, flows into the placenta
• Normal heart circulation

  Blood from SVC & IVC enters RA, through tricuspid valve to RV, through pulmonary valve to PA, to lungs, oxygenated blood returns to LA through pulmonary veins, through mitral valve to LV, through aortic valve to aorta
• Diagnostic and laboratory tests

  • Fetal echocardiography
  • Chest X-ray
  • Chemistry & hematology tests (K, Ca, Na, Hgb & hct, coagulation studies, CK, CK-MB, troponin, CRP, ESR, BNP, arterial blood gas)
  • Electrocardiogram (ECG)
  • Holter/Event Monitor
  • Transthoracic Echocardiogram
  • Computed Tomography/Magnetic Resonance Imaging
  • Exercise Stress Testing (EST)
  • Cardiac catheterization
• How to check on general appearance

  1. Inspect distal extremities for color & measure capillary refill time

  2. Inspect mucous membranes of the mouth (buccal membranes & lips) to assess cyanosis
• Assignment


  • How to perform the physical examination to child/children in assessing their cardiovascular system?
  • What are the different sites for cardiac auscultation?
  • What are the four heart sounds?
  • What is a heart murmur and the Levine grading scale for systolic murmurs?
• Cardiac output


  The volume of blood pumped by the ventricles each minute
• Factors affecting stroke volume

  • Preload - the volume of blood in the ventricles at the point just before contraction
  • Contractility - ability to modulate the rate and force of fiber shortening
  • Afterload - the amount of resistance met by the ventricles upon ejection
• Heart failure


  The inability of the heart to supply adequate oxygenated blood to meet the metabolic demands of the body
• Types of heart failure

  • Right sided failure
  • Left sided failure
• Signs and symptoms of right-sided heart failure

  • Periorbital edema (infants)
  • Enlarged liver
  • Weight gain
  • Edema
• Signs and symptoms of left-sided heart failure

  • Tachycardia
  • Dyspnea & rales
  • Tachypnea
  • Fatigue
• Left sided HF can ultimately lead to right-sided failure, as excessive pressure in the pulmonary system prevents blood from leaving the right ventricle
• Therapeutic management of heart failure

  1. Symptomatically manage the patient

  2. Treat the underlying cause of HF

  3. Decrease fluid overload, enhance myocardial contractility, & decrease afterload

  4. If HF is due to congenital heart defect - short-term treatment to stabilize the infant's medical status until safe intervention of the CHD is performed

  5. Use digoxin as the drug of choice
• Classification of congenital heart defects

  • Embryologic formation
  • Structure
  • Physiology - "increasing pulmonary blood flow", "decreasing pulmonary blood flow", "obstruction to systemic blood flow", single ventricle defects (hypoplastic left heart syndrome)
• Cyanotic heart disease


  Venous blood from the right side of the heart mixes with blood on the left side, this is a "right-to-left" shunt that delivers deoxygenated blood to the body
• Acyanotic heart disease


  Blood shunts "left to right" then oxygenated blood from the left side mixes with blood in the right side of the heart and goes back to the lungs again
• Defects that "increase pulmonary blood flow"

  • Patent Ductus Arteriosus
  • Atrial Septal Defect
  • Ventricular Septal Defect
  • Atrioventricular Septal Defect
  • Transposition of the Great Arteries
  • Anomalous Pulmonary Venous Return and Truncus Arteriosus
• Patent Ductus Arteriosus


  Occurs when this fetal shunt fails to close after several days of life, allowing blood to flow from the aorta (area of high pressure) through the PDA & into the main pulmonary artery (area of low pressure)
• Management of Patent Ductus Arteriosus

  1. Use diuretics (furosemide) if blood flow is significant

  2. Increase caloric concentration of the infant's feed to gain weight if low weight

  3. With heart dilatation = PDA closure

  4. In premature infants with HF due to PDA = use indomethacin to facilitate closure

  5. In older children = can be closed in the cardiac catheterization lab with a device placed in the duct to occlude flow
• Atrial septal defect


  Occurs when a portion of the atrial septal tissue does not completely form
• Types of atrial septal defects

  • Secundum type - most common, located in the center of the atrial septum
  • Primum defect - located low in the atrial septum near the IVC
  • Sinus venosus defects - located high in the septum where the pulmonary veins enter the left atrium and allow communication of one or more of the pulmonary veins with the right atrium
• Management of atrial septal defect


  1. If incidentally noted, is small & is producing no clinical symptoms = it will not be closed

  2. For clinically significant defects = management will be based on the child's age & the size of the defect

  3. Defects that fail to close with persistent shunting after an observation period = refer for closure to prevent the incidence of supraventricular dysrhythmias & prevent pulmonary vascular disease

  4. If the defect is larger with evidence of pulmonary blood flow = refer for closure
• Ventricular septal defect


  Occurs when a portion of the ventricular septum does not completely close
• Management of ventricular septal defect

  1. Medically manage to allow for spontaneous closure of the defect as the child grows

  2. Use diuretics if child exhibit signs of pulmonary overload

  3. Increase caloric density of the child's formula or human milk if poor weight gain

  4. If small = no need to be closed

  5. If large = refer for closure

  6. Use digoxin to slow & strengthen the heartbeat, helping to prevent fluid from accumulating in the lungs
• Atrioventricular septal defect


  May comprise several defects, most common type of CHD in children with trisomy 21, varying degrees of abnormality occur with this lesion, from mild septal defects to a complete lack of central septa with incompetent valves on both sides