WEEK 3 Flashcards
What is congenital heart disease defined as?
Heart disease that pt is born with
What are the 6 causes of congenital heart disease?
- Genetic defects
- Chromosome abnormalities (Downs, turners etc.)
- Intrauterine infection (Rubella)
- Drugs (thalidomide)
- Maternal alcohol (FAS, especially septal defects)
- Maternal diabetes
What is the mneumonic for the 4th arch derivative?
FOUR rhymes with aOR
Remember “fouRS”
- Arch of Aorta
- Right Subclavian Artery
What are 5 things that can go wrong & as a result lead to congenital heart disease?
- Failure of septation
- VSD, ASD - Failure of development
- obstruction: tricuspid/pulmonary atresia, pulmonary stenosis, coarctation of the aorta
- hypoplasia: hypoplastic left heart (no formation of L heart) - Failure of or incorrect rotation
- TGA & congenitally corrected transposition of the great vessels, dextrocardia - Abnormalities of the great vessels
- wrong connections: transposition of the great vessels
- wrong embryology: trucus - Failure of closure
- PDA
What is the incidence of congenital heart disease in live births? What is the most common & least common type of congenital heart diseases?
About 1% of live births
Most common = VSD
Least common = aortic stenosis & Fallot’s Tetralogy
What are the issues & presentation of congenital heart disease? (HINT: there’s 4 points)
- INCIDENTAL
- murmur, echo finding - HEART FAILURE
- Qp(pulmonary flow)>Qs (systemic flow) (shunt ratio) - CENTRAL CYANOSIS
- >5g/dl deoxyhaemoglobin resulting from venous mixing with systemic blood - PULMONARY HYPERTENSION = >30mmHg systolic resulting from increased Qp
What are the 6 presenting problems if congenital heart disease?
- Heart failure
- difficulty feeding
- failure to thrive (don’t pass milestones)
- tachypnoea (rapid breathing)
- cyanosis - Cyanosis
- Clubbing
- Murmur
- Squatting (Fallot’s)
- Syncope
How is congenital heart disease prevented?
Foetal echocardiography
How is congenital heart disease managed palliatively? (relieving pain w/out dealing with the cause of the condition)
- To allow growth for definitive treatment:
- Maintain arterial duct (prostaglandins)
- PA banding
- Atrial septostomy (Rashkind) - As long-term treatment
- Creation of systemic to pulmonary shunt (Subclavian to PA (Blaylock) OR Central PA to Aorta (Waterstone)) - Definitive treatment:
- Radical correction of TGA, Fallots
- Percutanous closure devices - PDA, ASD, VSD - Transplantation
- Heart
- Heart-lung for conditions complicated by PHT
What are the 7 complications associated with congenital heart disease?
- Failure to thrive
- Paradoxical embolus (venous to arterial)
- Endocarditis
- Pulmonary hypertension
- Polycythaemia
- Haemoptysis
- Arrythmias - flutter, VT/VF
What is an atrial septal defect?
Blood flows between the atria. Normally, the atria are separated by the interatrial septum. If this septum is defective/absent, then oxygen-rich blood can flow directly from the left side of the heart to mix with deoxygenated blood in the R side of the heart, or vice versa. This can lead to lower-than-normal oxygen levels in the arterial blood that supplies the brain, organs, & tissues. NOTE: an ASD may not produce noticeable signs or symptoms, especially if the defect is small
What 2 ways is an atrial septal defect (ASD) managed? How is it decided which route to go down?
- Nothing
- Percutaneous closure
- it depends on the size of the shunt
What is the most common ventricular septal defect?
Perimembraneous
If a patent ductus arteriosus is larger what can happen? What does it cause if it is small?
It will present as heart failure with continuous murmur & wide pulse pressure
Can cause PAH (pulmonary arterial hypertension) but this will only show lower body cyanosis.
If small it causes a “continuous murmur” normal pulse pressure
What is coarctation of the aorta? Who is it common in? What can it cause? What 2 things can it be associated with?
A large range of narrowing from complete interruption to small low gradient stenosis
More common in males (if in females, think of Turners)
Causes systemic hypertension in adults
Associated with intercranial aneurysms & bicuspid aortic valve
What is TGA (transposition of the great arteries)?
When the 2 main arteries going out of the heart—the PA and the Ao—are switched in position, or “transposed”.
How is TGA palliated? (means to relieve or lessen without curing) (HINT: there’s 4 things)
Pharmacologic maintenance of arterial duct
Atrial septostomy
Radical switch procedure
(Palliative surgery – Mustard procedure)
How does oxygenated blood from the umbilical vein bypass the lungs? Why does it bypass the lungs?
- Crossing the oval fossa (inter-atrial septum)
- Passing from PA to Ao through arterial duct (ductus arteriosus)
The lungs are not inflating, as resistance is very high so blood cannot get through
What diseases (i) with shunts (ii) without shunts will the pt present as cyanotic?
(i) All but with PHT (eisenmenger’s complex)
TGV
Fallot’s tetralogy
(ii) Hypoplastic left heart
V. severe pulmonary stenosis
Pulmonary/tricuspid atresia with OR without intact septum
What diseases (i) with shunts (ii) without shunts will the pt present as acyanotic?
(i) ASD, VSD, PDA
(ii) pulmonary stenosis
coarctation of the Ao
Aortic/L.heart obstruction
What is Eisenmenger’s complex/syndrome?
defined as the process in which a long-standing left-to-right cardiac shunt caused by a congenital heart defect causes pulmonary hypertension & eventual reversal of the shunt into a cyanotic right-to-left shunt.
What are the investigations done for congenital heart diseases?
- Echocardiography & doppler measurement
- Cardiac catheterisation
- used much less but still needed sometimes to measure PA pressure - Genetic
What is the difference in the primum & secundum ASD?
Primum = is often complicated by other lesions e.g. mitral valve clefts, anomalous venous drainage
Secundum usually uncomplicated.
Describe (i) Small VSDs (ii) Large VSDs.
(i) Safe, never cause PAH but have a loud murmur. No treatment necessary
(ii) have high Qp:Qs, present in early infancy. Palliated until definitive treatment. Have a loud holosystolic murmur
What are the 2 types of treatment for coarctation of the aorta?
Balloon dilatation
Sometimes surgery
What are the signs for coarctation of the Ao?
Absent/delayed femoral pulse
Lower BP in legs
Scapula collaterals
Rib notching on chest Xray
What is Tetralogy of Fallot?
involve four anatomical abnormalities of the heart (although only three of them are always present).
- Pulmonary stenosis
- VSD
- Over-riding aorta
- Right ventricular hypertrophy
Why is the Tetralogy of Fallot of particular interest? (There’s 2 reasons)
It is a definitive cause of cyanosis but one which is reversible as they never had PAH
Squatting is a common characteristic to raise systemic resistance (often after exercise)
How is the severity of Tetralogy of Fallot determined?
By degree of RV outflow obstruction
What are the fundamentals of a cardiovascular examination?
INTRO - hygiene of hands & stethoscope, introduce, name, DoB, discomfort, explain, permission, position at 45degrees with chest adequately exposed
INSPECTION
PALPATION
(PERCUSSION)
AUSCULATION
OTHER AREAS
CONCLUSION (thanks, wash hands, summarise & present findings orally)
What does the inspection of a CV examination consist of?
At end of bed: - look around pt (oxygen, cigarettes), look at pt (breathless, discomfort, pain), Inspect hands (warmth, capillary refill) - peripheral cyanosis - nail clubbing - tar staining - splinter haemorrhage - koilonchyia - oslers nodes - janeway lesions, Look at face eyes & mouth (pallor, sweating) - central cyanosis - malar flush - conjunctivae - xanthelasma - corneal arcus
What pulses are taken in a CV examination? (HINT: there’s 3)
RADIAL PULSES:
- palpate both
- rate
- rhythm (if irregular take pulse for one min)
- collapsing pulse (aortic regurgitation)
CAROTID PULSE:
- one at a time
- volume
- character
BLOOD PRESSURE:
can be done now with other two or at end of examination
What are the types of abnormal rate/rhythm of pulses that can be heard & what do they suggest?
- Fast & regular
e. g. exercise, anxiety, pain, fever, medication, hyperthyroidism - Regularly irregular
e. g. ectopic beat - Irregularly irregular
e. g. atrial fibrillation (fast if uncontrolled) - risk factor for stroke - Slow & regular (bradycardia)
e. g. athletic training, hypothyroidism, medication (beta blockers) - Slow & irregular
e. g. Sick sinus syndrome, second degree heart block, complete heart block
What are the types of abnormal volume/character of pulses that can be heard & what do they suggest? (In the carotid pulse)
- Low volume
e. g. hypovolaemia, left ventricular failure - Increased volume
e. g. anaemia, fever, thyrotoxicosis - Character
- Slow rising pulse = aortic stenosis
- Collapsing pulse = aortic regurgitation
Ausculation is one of the steps in a CV exam, describe the stages of this step.
- Palpate the carotid pulse initially
- distinguish the 1st & 2nd heart sounds - Listen for:
- heart sounds
- added sounds
- murmurs (turbulent blood flow) - Use bell & diaphragm & listen in all 4 key areas (aortic, pulmonary, tricuspid, mitral)
- Manoeuvres to accentuate murmurs & remember carotids
What are the 4 movements done to accentuate murmurs?
- At apex in left lateral position
- Bell at apex
- In expiration
- Accentuation of mitral stenosis - At left axilla
- With diaphragm
- Radiation of systolic murmur of mitral regurgitation - At lower left sternal edge with patient sat forwards
- With diaphragm
- In expiration
- Accentuation of atrial regurgitation - Over carotids
- With diaphragm
- In held inspiration
- For aortic radiation/carotid bruits
What is the JVP? Where is it located? What is it measured as? What tests are done to ensure it is the JVP you are palpating & not the carotid
Jugular venous pulse
Between clavicular & sternal heads of sternoceidomastoid
- measured as the vertical height of the highest point of pulsation above the sternal angle (should be less than 4cm)
Tests: Double wave form of venous pulsation, it can be obliterated by gently occluding vein, abdominojugular reflex
What steps are done when looking at the praecordium?
- LOOK
- shape, RR, scars, visible apex beat, pacemaker - APEX BEAT
- find it first then check its position (“normal” = 5th IC space mid-clavicular line) - HEAVES
- left sternal edge, RV enlargement - THRILLS
- palpable murmur (apex, upper praecordium, sternal notch)
What are the 4 sites for auscultation?
5th IC space mid clavicular line = mitral
4th IC space L sternal edge = tricuspid
2nd IC space L sternal edge = pulmonary
2nd IC space R sternal edge = aortic
How are murmurs graded?
1/6 = very quiet ABSENT 2/6 = Quiet ABSENT 3/6 = Easily audible ABSENT 4/6 = Loud PRESENT 5/6 = V.loud PRESENT 6/6 = Audible w/out stethoscope PRESENT
What is a “thrill”?
A palpable murmur that you can hear with your hands
What other areas are needed to be examined to complete a CV examination?
- Ausculate lung bases
- Sacral oedema
- Offfer abdominal examination
- Peripheral vascular examination (femoral, popliteal, dorsalis pedis & post tibial, oedema)
- Ankle oedema
- BP
- Fundoscopy
- Urinalysis
- Observation chart
What is the difference between between locus heterogeneity and allelic heterogeneity?
LOCUS HETEROGENEITY = defects in more than one gene can cause the same phenotype
ALLELIC HETEROGENEITY = different mutations in the same gene can cause the same disease
What is genetic penetrance?
The proportion of individuals carrying a particular variant of a gene (allele or genotype) that also expresses an associated trait (phenotype).
In medical genetics, the penetrance of a disease-causing mutation is the proportion of individuals with the mutation who exhibit clinical symptoms
What are 4 common CV defects in down syndrome?
Atrial septal defect
Ventricular septal defect
AV septal defect
Patent ductus arteriosus
If someone has 22q11.2 deletion syndrome (DiGeorge Syndrome) their signs/symptoms are remembered by CATCH-22, what does this stand for?
Cardiac abnormalities Abnormal facies Thymic aplasia Cleft palate Hypothyroidism
What are the cardiac abnormalities involved in 22q11.2 deletion syndrome (DiGeorge Syndrome)?
- Interruption of aortic arch
- Tetralogy of Fallot
- Ventricular septal defect
DiGeorge Syndrome can arise without deletion, explain how this is the case.
Mutation(s) in TBX 1
What happens if you lose 1 copy of the TBX1 gene?
Loss of 4th pharyngeal arch arteries