Congenital Heart Defects Flashcards
Tetralogy of Fallot
Right Ventricular Hypertrophy
Ventricular Septal Defect
Right-sided Outflow Obstruction (Pulmonary Stenosis)
Over-riding Aorta
In which direction is blood generally shunted in a Ventricular Septal Defect?
Left to right
non-cyanotic
Where on the precordium are Ventricular Septal Defects usually best auscultated?
Lower left sternal edge
Accompanied by a parasternal thrill
What is Eisenmengers Syndrome?
With established Ventricular Septal Defects, increased pulmonary blood flow leads to increased pulmonary vascular resistance. This causes pulmonary hypertension and the VSD shunt becomes right to left and cyanotic
What is the treatment of choice for Ventricular Septal Defects before surgery is needed?
Furosemide with Spironolactone
What is the definition of congenital heart disease?
A gross structural abnormality of the heart or intrathoracic great vessels that is actually or potentially of functional significance
Present at birth
What is a “mild” defect?
Asymptomatic
May resolve spontaneously
May progress to moderate pr severe in adulthood in some specific conditions
What is a “moderate” defect?
Requires specialist intervention and monitoring in cardiac centre
What is a “severe” defect?
Present severely ill/die in newborn period or early infancy
What is a “major” congenital heart disease?
Requires surgery within the first year of life
How does an unwell baby with congenital heart disease present?
Cyanosis
Shock
Cardiac failure
Why is the outcome probably better for major disease if antenatally detected?
Avoid cardiovascular collapse/death if undiagnosed
Minimise hypoxia
Improve condition at time of going to surgery
How is a right to left shunt at ductus detected at newborn screening?
Measurement of pre and post ductal saturations
Pre = Right hand
Post = Left hand, feet
Difference of 3% or more suggests shunt
What kinds of heart defects causes cyanosis in a newborn baby?
Any condition causing deoxygenated blood to bypass the lungs and enter the systemic circulation
Any condition where mixed oxygenated and deoxygenated blood enters the systemic circulation from the heart
What is the differential diagnosis of cyanosis in a newborn, and what are the defining features of each?
Cardiac disease =
Babies tend to be blue
Little or no respiratory distress
Pre-post ductal difference
Respiratory disease =
Increased work of breathing
X-Ray changes
Persistent pulmonary hypertension of the newborn =
baby otherwise very unwell
Large pre-post ductal difference
What specific congenital heart defects can cause cyanosis?
Transposition of great arteries
Tetralogy of Fallot
Tricuspid atresia
Pulmonary atresia with intact ventricular septum
Total anomalous pulmonary venous connections
What has occurred in Transposition of the Great Arteries?
Aorta leaves from the right ventricle, and so deoxygenated blood is passed around the body without ever reaching the lungs
Pulmonary artery leaves the left ventricle, and so oxygenated blood is pumped round the lungs without ever reading the body
A patent foramen oval will allow for some mixing of blood, but this is not sufficient and treatment should be given ASAP
What are duct dependent lesions?
Any conditions in which the pulmonary or systemic circulation is dependent on the potency of the ductus arteriosus
If not detected beforehand, will present with circulatory collapse when the duct closes
What treatment can be given to maintain duct patency in duct dependent lesions?
ABC
Low dose prostaglandin E2
Watch for apnoea, but avoid ventilation and intubation if possible
Transfer to cardiac surgical centre for definitive management
What is the typical presentation of undiagnosed duct dependent lesions?
3-5 day old infant suddenly pale, tachypnoeic and distressed
Pallor, prolonger CRT, poor or absent pulses, hepatomegaly, crepitations, increased work of breathing
Profoundly acidotic
What is the differential diagnosis for an undiagnosed duct dependent lesion?
Sepsis
Metabolic conditions
What are some duct dependent systemic circulatory conditions?
Hydroplastic left heart
Critical aortic stenosis
Interrupted aortic arch
Critical coarctation of aorta
What are some cut dependent pulmonary circulatory conditions?
Tricuspid atresia
Pulmonary atresia
Why might a baby present with cardiac failure?
Large VSD
Moderate to large left to right shunt
Increased pulmonary flow, Increased ventricular load
What are the clinical signs of failure in babies?
Failure to thrive Slow/reduced breathing Breathlessness (especially when feeding) Sweatiness Hepatomegaly Crepitations
