Cyanotic Heart Lesions Flashcards
What is the definition of cyanosis?
- it is defined as blue discoloration of the skin and mucous membranes associated with poor oxygenation
- mostly when >5g/dL of deoxygenated hameoglobin
What are the characteristics of peripheral cyanosis?
- Pink tongue
- Normal PaO2
- Capillary refill is >2 seconds
What are the characteristics of central cyanosis?
- Discoloration of skin and mucous membranes
- Decreased PaO2 and SPO2
- Capillary refill<2 seconds
What is differential cyanosis?
When the SATS of the lower limb are lower than the SATS of the upper limb
What is reversed differential cyanosis?
When the SATS of the upper limb are lower than the SATS of the lower limb
If a baby is born and has SATS of <90%, what should we start to consider in that patient?
Cardiac disease may be possible and baby must be sent for an echocardiogram
If that same baby has SATS of 90-94% what is your next decision?
- Cardiac disease is unlikely but we need to recheck saturation after 1 hour
- If after that hour it is above >95% it is not cyanotic heart disease
- If it is <95% then cyanotic heart disease is suspected and we need to do a echocardiogram
If that same baby is >95% what is the next step?
-We would recheck 12 hours later and see that cyanotic heart disease is excluded
If a neonate presents with sudden onset of cyanosis or shock what should we consider?
- That it is a duct dependent lesion until proven otherwise
- And we treat this with prostaglandins
What is tetralogy of fallot?
-It is a congenital condition comprising of 4 heart abnormalities
- Stenosis of the right ventricular outflow tract
- Right ventricular hypertrophy
- Ventricular septal defect
- Aorta overrides the ventricular septal defect
How does tetralogy of fallot present?
- cyanosis especially of the lips and fingertips
- clubbing of fingers and toes
- any decrease in oxygen which leads to a range of symptoms such as feeding difficulty, failure to thrive
What is the management of tetralogy of fallot(tet spell)?
- Start by giving oxygen
- Give fluid boluses
- Give them morphine to relax+ Sodium bicarbonate for metabolic acidosis
- Give beta-blockers(IV preferred)-propanolol
- Then give vasoconstrictors(phenylephrine, ketamine, noradrenaline)
What would we expect on ECG for babies with tricuspid artresia?
-left axis deviation (positive deflection in LEAD 1 and negative deflection in AVF
What two groups is cyanotic heart defects broken up into?
- Cyanotic with decreased pulmonary flow
2. Cyanotic with increased pulmonary flow
What is the main problem leading to tetralogy of fallot?
Pulmonary stenosis and subsequent right ventricular hypertrophy
Which ages does it occur in mostly?
6 months to 5 years
What murmur is usually associated with tetralogy of fallot?
Ejection systolic murmur in the pulmonary area and radiating to the left clavicle
What happens as a result of the presence of a VSD and the pulmonary stenosis?
There is overriding of the aorta and the desaturated blood flows from the right ventricle into the aorta
What are the 4 defects associated with tetralogy of fallot?
- Pulmonary stenosis
- Right ventricle hypertrophy
- VSD
- Overriding aorta
What syndrome is tetralogy common in?
DiGeorge syndrome
What is a tet spell?
It is a hyper cyanotic spell where the child is overusing oxygen causing more desaturation. From then on the baby usually squats to try and increase SVR and cause shunting back into the right ventricle and blood flow into the pulmonary artery
What are the clinical features of tetralogy of fallot?
- Cyanosis-fingers and lips
- Clubbing
- Poor feeding and growth
- Ejection systolic murmur
How do we diagnose tetralogy of fallot
?
We usually do a echocardiogram
How do we manage tetralogy of fallot?
Surgery usually in the first year
What is tricuspid valve atresia?
The absence of a tricuspid valve and so blood cannot go into the right ventricle
-usually presents with ASD and VSD and hypoplastic right ventricle
What do we use to diagnose tricuspid atresia?
- Echocardiogram
- ECG
- X-ray(decreased pulmonary markings)
What happens if we do not do anything about tricuspid valve atresia?
75% will die early in childhood
What causes Ebstein’s anomaly?
Prenatal Lithium consumption by mom
What happens to the tricuspid valve during ebstein’s anomaly?
- there is atrialisation of the right ventricle into the right atrium
- there is right to left shunting of deoxygenated blood through the foramen ovale
What murmur can we expect in patients with ebstein’s anomaly?
Tricuspid regurgitation -wide split s2 with holosystolic murmur at left sternal border
What is eisenmenger’s syndrome?
It is a severe VSD caused by increased pulmonary hypertension
There is then a right to left shunt and this also presents with right ventricular hypertrophy
What else do patients with eisenmenger’s disease also present with?
Chest deformities like asymmetry, Harrison’s sulcus and pectus carinatum
What is transposition of the great arteries?
It is the swapping of the aorta and the pulmonary artery.
- The aorta is in the right ventricle and the pulmonary artery is in the left ventricle
- this leads to two separate circulations
What are the risk factors for developing transposition of the great arteries?
Born to diabetic mom’s
What are the clinical signs of transposition of the great arteries?
- cyanosis soon after birth
- tachypnea
- loud S2
- If VSD is present then systolic murmur at the left lower sternal border
What can we expect to find on X-ray for transposition of the great arteries?
Egg on a string appearance
How do we diagnose transposition of the great arteries?
- Echocardiogram
2. X-ray with egg on a string
What is the management of transposition of the great arteries?
- give prostaglandin to prevent closure of the PDA initially
- surgical management is necessary within 2 weeks of later
- if there is no treatment, 90% die within the first year of life
What is persistent truncus arteriosus?
This is the failure of the separation of the pulmonary artery and the aorta because of a VSD directly below these trunks
-blood from both ventricles flow into the arteries
What are the clinical signs of truncus arteriousus?
- Cyanosis
- Bounding or collapsing pulses
- Wide pulse pressure
- Harsh systolic murmur at the left lower and sternal border and loud S2
What special investigations would we do in these patients?
- Echocardiography
- ECG
- Chest X-ray
What is total anomolous pulmonary venous connection?
This when pulmonary veins(with oxygenated blood) connect to the right atrium instead of the left atrium
What are the 3 areas that the pulmonary veins connect to the right atrium in TAPVN?
- supracardiac-in SVC
- intra-cardiac in the right atrium
- infracardiac-in the IVC
What septal defect do these patients often have to survive?
ASD or foramen ovale
What murmurs can we expect in these patients?
Loud S2 with fixed splitting
-loud pulmonic ejection systolic because of the increased volume in the right atrium and ventricle
What special investigations can we do in total anomalous pulmonary venous connection?
Chest X-ray- figure 8 or snowman shape with plethoric lung fields
What drugs contribute to congenital heart defects?
Phenytoin
Lithium
Retinoic acid
What maternal condition can contribute to the child developing congenital cardiac lesions?
Diabetes mellitus
Systemic Lupus Erythematosus
What common syndromes present with cardiac anomalies?
- Down’s syndrome
- FAS
- Trisomy 13
- Trisomy 18
What is pectus carinatum associated with?
Marfans syndrome
What is Harrison’s sulcus caused by?
Increased plain experience of the chest
- rickets
- increased work of breathing
- left to right shunt lesions
What is corrigans sign?
Visible pulsation in the neck associated with aortic regurgitation
What does absent femoral pulses indicate?
Coarcation of the aorta
What could absent or pulses indicate?
Takayashus arteritis
What is a thrill in the right upper sternal border associated with?
Aortic stenosis
What is a thrill felt over the left upper sternal border associated with?
Right ventricular outflow obstruction
What is a thrill felt over the left lower sternal border associated with?
A ventricular septal defect