Cardiology Flashcards
Day 3
Define CHD ?
Anatomical malformation of the heart or great vessels occurring during fetal development
1/125 born with a congenital heart defect (1 in 100 in the UK)
Most common form of structural birth defect.
Define acquired disorders
Disease processes or abnormalities that occur after birth. They result from various causes such as infection, autoimmune diseases, environment factors.
Describe embryonic heart development
Cardio genesis begins at approximately 3 weeks of gestation. Most cardiovascular development occurs between weeks 4 and 8 when the formation of the atria and ventricles.
During prenatal development, the heart is already functioning and preparing to adapt to postnatal life.
Describe foetal circulation
Oxygenation of the blood is from the placenta rather than the lungs
Fetus has low levels of oxygen (60-70%)
To compensate the fetal cardiac output is high
Fetal cardiac shunts – Foramen ovale and ductus arteriosus
What are the 3 layers of an artery ?
Adventitia (protective outer layer)
Media (Smooth muscle layer)
Intima (non stick inner lining)
Examples of acyanotic CHD
Ventricular septal defect, atrio ventricular septal defect, patent ductus arteriosus, aortic valve stenosis, pulmonary valve stenosis, coarctation of aorta
How is CHD classified ?
Cyanotic - Not enough oxygen to the body.
Acyanotic - blood is shunted from the left to the right side of the heart often due to a hole.
Examples of cyanotic CHD
Tetralogy of Fallot, tricuspid atresia, hypoplastic left heart syndrome, transportation of great arteries, total anomalous pulmonary vein return, truncus arteriosus, severe pulmonary stenosis
Causes and factors associated with CHD
Environmental factors include:
Infection – intrauterine, systemic viral (rubella, herpesvirus)
Metabolic disorders – Diabetes, hypercalcemia, phenylketonuria (PKU)
Drugs – Alcohol, warfarin, phenytoin, thalidomide, lithium
Peripheral conditions – antenatal age, antepartum bleeding, prematurity, high altitude
A number of chromosomal anomalies and congenital lesions associated with increased risk of CHDs
What is VSD ?
A ventricular septal defect (hole) of the interventricular septum, the wall separating the right and left ventricles
The high pressure in left ventricle causes left-to-right shunt of blood into right ventricle
The increased blood flow to the lungs over time increases pulmonary vascular resistance
This causes the right ventricle to hypertrophy
How to diagnose CHD
Prenatal scans, structure of heart visualised at 20 weeks, if abnormal echocardiography undertaken before 24 weeks, murmur detected after birth
Symptoms of VSD in babies
Poor eating, failure to thrive
Fast breathing or breathlessness
Easy tiring
What is ASD ?
An atrial septal defect is a birth defect of the heart in which there is a hole in the wall (septum) that divides the upper chambers (atria) of the heart
The slightly higher pressure from left atrium causes oxygenated blood to flow from left atrium through the septal defect to right.
This additional blood flow to right side of heart can cause stretching and enlargement
What are the symptoms of ASD ?
Shortness of breath, especially when exercising
Fatigue
Swelling of legs, feet or abdomen
Heart palpitations or skipped beats
Stroke
Heart murmur
What is PDA ?
Patent ductus arteriosus (PDA) is a persistent opening between the aorta and the pulmonary artery
Higher pressure from aorta shunts blood into the pulmonary artery resulting in blood being pumped to lungs and back to left atrium
A small patent ductus arteriosus often doesn’t cause problems
A large patent ductus arteriosus allows poorly oxygenated blood to flow in the wrong direction, weakening the heart muscle and causing heart failure
What might a large PDA found during infancy cause ?
Poor eating, which leads to poor growth
Sweating with crying or eating
Persistent fast breathing or breathlessness
Easy tiring
Rapid heart rate
What is ACHD ?
Adult congenital heart disease, affects aged over 18 living with heart defect that occurred during foetal development.
What is acquired cardiac disease in CYP ?
Are those disease processes or abnormalities that occur after birth
Examples of acquired disorders are: Kawasaki disease, paediatric inflammatory multisystem syndrome, rheumatic heart disease, cardiomyopathy
Eating disorder and cardiovascular complications
What are the cardiovascular complications associated with ED ?
Most common are hypotension and bradycardia
Sinus bradycardia- compensate for starved body to conserveenergy and is mediated by increased vagal tone
Hypotension occurs secondary to increased vagal tone and may also result from poor fluidintake and dehydration, reduced elasticity in blood vessels, and dysregulation of circadianrhythm
What is Kawasaki disease ?
Acute vasculitis (inflammation of blood vessels)
Leading cause of acquired heart disease in children
Aetiology and pathogenesis – unknown (may be immune response)
What are the symptoms and treatment of Kawasaki disease ?
fever >39 for 5 days or longer, bilateral conjunctivitis, red cracked lips, strawberry tongue, oedematous hands and feet and peeling
Treatment: IV gamma globulin, Aspirin +/- Anticoagulation, corticosteroids
What is PIMS ?
Paediatric inflammatory multisystem syndrome, temporally associated with COVID. Similar coronary artery changes as Kawasaki disease.
What are the symptoms of PIMS ?
persistent fever, inflammation (neutrophilia, elevated CRP and lymphopaenia) and evidence of single or multi-organ dysfunction ( shock, cardiac, respiratory, renal, gastrointestinal or neurological disorder)
What is rheumatic fever ?
Immune-mediated multi-system inflammatory disease (heart, skin connective tissue)
Rheumatic heart disease is the cardiac aspect of RF (inflammation of pericardium, myocardium, endocardium, can cause cardiac dilation and heart failure)
