Cardiology Flashcards
(121 cards)
1
Q
What is the purpose of the fetal shunts/why do fetus’ require fetal shunts?
A
Lungs are not fully developed or functional (fetus is not breathing) therefore there is no point in blood passing through the pulmonary circulation and secondly large volumes of blood passing through lungs could cause damage
2
Q
For each of the 3 fetal shunts, state:
- The name of the shunt
- Where it shunts blood from and to
- What the shunt is trying to bypass
A
- Ductus venosus: umbilical vein to IVC to allowing blood to bypass liver
- Foramen ovale: right atrium to left atrium allowing blood to bypass right ventricle & the pulmonary circulation
- Ductus arteriosus: pulmonary artery to the aorta allowing blood to bypass the pulmonary circulation
3
Q
Describe what happens to the fetal shunts at birth when baby takes it’s first breath
A
Foramen ovale
- When baby takes it’s first breath it expands the alveoli
- Causing decrease in pulmonary vascular resistance
- Causing fall in pressure in RA
- LA pressure > RA pressure
- Septum primum forced against septum secundum causing functional closure of foramen ovale (gets sealed shut few weeks later and becomes fossa ovalis)
Ductus Arteriosus
- Prostaglandins are required to keep it open
- Increased blood oxygenation causes decrease in circulating prostaglandins
- Therefore ductus arteriosus closes within 1-3 days after birth (in full term babies) and becomes ligamentum arteriosum
Ductus venosus
- Umbilical cord is clamped immediately after birth therefore there is no flow through umbilical veins hence ductus venosus stops functioning
- Closes a few days later to become ligamentum venosum
4
Q
State some potential risk factors for congenital heart disease
A
While some things are known to increase the risk of congenital heart disease, no obvious cause is identified in most cases:
- Rubella infection in first 8-10 weeks pregnancy
- Influenza infection in first trimester
- Alcohol use during pregnancy (may lead to fetal alcohol syndrome which is associated with congenital heart disease)
- If mother has T1DM or T2DM (not gestational diabetes)
- Genetic conditions e.g. Down’s syndrome, Noonan syndrome, Turner syndrome
5
Q
State the 8 cyanotic congenital heart conditions
*HINT: 5 T’s and 3 others
A
- Transposition of great arteries
- Tricuspid atresia
- Tetralogy of fallot
- Truncus arteriosus
- Total anomalous pulmonary venous return (TAPVR)
- Hypoplastic left heart syndrome
- Pulmonary atresia
- Ebstein’s anomaly
6
Q
State the 7 types of acyanotic congenital heart disease
A
- ASD
- VSD
- Atrioventricular septal defect
- PDA
- Congenital aortic stenosis
- Coarctation of the aorta
- Pulmonary valve stenosis
7
Q
Innocent/flow murmurs are very common in children; what are innocent flow murmurs caused by?
A
Fast blood flow through various areas of heart during systole
8
Q
State 5 characteristic features of innocent/flow murmurs
A
- Soft
- Short
- Systolic
- Symptomless
- Situation dependent (e.g. gets quieter with standing, only appears when child is unwell or feverish)
9
Q
Innocent/flow murmurs with no concerning features may not require further investigations; state some features that would prompt further investigation & referral to paediatric cardiologist
A
- Murmur louder than 2/6
- Diastolic murmurs
- Louder on standing
- Other symptoms e.g. failure to thrive, feeding difficulty, cyanosis, SOB
10
Q
If a murmur in a child required further investigations, what investigations would you do? (3)
A
- ECG
- CXR
- Echocardiography
11
Q
Where would you best hear a pan-systolic murmur due to a ventricular septal defect?
A
Left lower sternal border
12
Q
What is an ASD?
State the 4 different types of ASD- put in order of most common
A
ASD is a hole in the septum between the two atria causing blood to flow from L to R
Types:
- Ostium secondum (septum secondum fails to fully close/ostium secondum fails to close. At level of fossa ovalis. 70%)
- Ostium primum (septum primum fails to fully close/fuse with endocardial cushions. Can be partial with intact ventricular septum and AV valves or complete with associated ventricular septal and AV valve defects)
- Sinus venosus: located near top of atrial septum and frequently associated with abnormal connection of pulmonary vein(s) to the RA instead of the LA
- Unroofed coronary sinus: atrial septal defect characterized by a deficiency in the tissue separating the coronary sinus from the left atrium (LA). This results in partial or complete unroofing of the coronary sinus leading to a predominantly left-to-right shunt through the coronary sinus
*remember septum secundum is on the right
13
Q
What would you hear on auscultation of heart in pt with ASD? Include:
- What murmur you hear
- Where it’s heard loudest
A
- Mid-systolic, crescendo-decrescendo murmur with a fixed split second heart sound
- Heard best at upper left sternal border (pulmonary valve area)
14
Q
Explain the pathophysiology of fixed split heart sound
A
- Fixed split heart sound= does not change with inspiration or expiration
- Occurs in ASD because blood is flowing from LA to RA increasing the volume of blood in RA and therefore the RV. This increases the volume of blood the RV has to empty before the pulmonary valve can close hence the pulmonary valve closes after the aortic vavle
15
Q
Explain the pathophysiology behind splitting of the second heart sound in relation to inspiration
A
- During inspiration the chest wall moves outwards and upwards and diaphragm moves down causing a decrease in thoracic pressure (known as negative intra-thoracic pressure) to increase volume of lungs. This also increases volume of heart.
- This decrease in pressure causes blood to flow faster into RA from the venous system
- The increased volume in the RV means it takes longer for the RV to empty during systole
- This causes a delay in the pulmonary valve closing
- Pulmonary valve closes slightly later than aortic valve causing split second heart sound
16
Q
ASDs are often picked up through antenatal scans or new-born examinations. May be symptomatic or asymptomatic in childhood. Asymptomatic children may become symptomatic as an adult. Discuss how an adult with an ASD may present
A
- Dyspnoea
- Heart failure (right sided)
- DVT leading to stroke (DVT embolises to RA, flow via ASD into LA, into LV, into aorta, up to brain causing stroke. If didn’t have ASD would have embolised in lungs causing PE. COMMON EXAM Q)
17
Q
ASDs are often picked up through antenatal scans or new-born examinations; may be asymptomatic or symptomatic in childhood. State some potential symptoms of ASD in childhood
A
- SOB
- Difficulty feeding
- Poor weight gain
- Frequent LRTI
18
Q
ASDs do not lead to cyanosis as blood continues to flow through pulmonary arteries to lungs to get oxygenated; however, it can have consequences for the right side of the heart. Discuss these consequences
A
- Blood flows LA to RA
- Increased flow of blood to right side of heart and through pulmonary arteries
- This can lead to hypertrophy and enlargement of pulmonary trunk
- Leading to pulmonary hypertension
- This can lead to RV hypertrophy and right sided heart failure
**Eventually if pulmonary hypertension increases so that pulmonary pressure > systemic pressure shunt may reverse- flowing R to L- and pt would become cyanotic (Eisenmenger syndrome)
19
Q
What might you find on ECG of child with ostium secondum ASD?
What might you find on ECG of child with ostium primum ASD?
A
- Ostium secondum: RBBB with RAD
- Ostium primum: RBBB with LAD, prolonged PR interval
May have tall P wave (P pulmonale) in both due to right atrial enlargement
20
Q
Is a patent foramen ovale a true ASD?
A
No!
21
Q
There is a possible link between migraine with aura and PFO; true or false?
A
True
22
Q
Discuss the management of ASDs
A
- Refer to paediatric cardiologist for ongoing management
- If small (<5mm) & asymptomatic can watch and wait
- Surgery if larger (>1cm) and/or symptomatic:
- Transvenous catheter closure
- Open heart surgery
- Diuretics if heart failure
- Anticoagulants (aspirin, warfarin & DOACs) used to reduce risk of clots & strokes in adults
23
Q
State some potential complications of ASDs
A
- Stroke (DVT embolising)
- Atrial fibrillation
- Atrial flutter
- Pulmonary hypertension
- ^^ and right sided heart failure
- Eisenmenger syndrome
24
Q
Remind yourself of the 5 steps of formation of the interatrial septum
A
- Endocardial cushions develop in atrioventricular region; growing from the dorsal and ventral surfaces then fusing in the midline
- Septum primum grows downwards towards (cranial to caudal) towards fused endocardial cushions. Before it fuses it forms a hole called the ostium primum.
- A second hole then forms in the septum primum, the ostium secondum before the ostium primum closes
- Ostium primum closes
- A second septum, septum secondum, then forms to the right of the septum primum; as it forms it creates a hole called the foramen ovale
25
What is a PDA?
What is the direction of blood flow through a PDA?
* Patent ductus arteriosus (fails to close in first 1-3 days)
* Aorta to pulmonary artery (down pressure gradient)
26
State some potential risk factors for PDA
* Prematurity
* Maternal infections e.g. rubella
* FH of congenital heart conditions
* Genetic conditions e.g. Down's syndrome
* Born at high altitude
27
A PDA can be detected during newborn examination if a murmur is heard; what murmur is heard when there is a PDA and where is it heard best?
* **Continuous crescendo-decrescendo ‘machinery’ murmur** which may continue into 2nd heart sound making it difficult to hear. First heart sound is normal.
* **2nd ICS left** *(pulmonic area)*
*\*\*\***A* *patent ductus arteriosus* *causes a* *continuous murmur* *since there is a* *constant* *pressure gradient in both systole and diastole forcing blood from the aorta into the pulmonary artery*
28
Alongside a continuous crescendo-decrescendo machinery murmur what else may you find on examination of pt with PDA?
* left subclavicular thrill
* large volume, bounding, collapsing pulse *(due to low diastolic pressure as blood moves from aorta to pulmonary arteries)*
* wide pulse pressure
* heaving apex beat
29
If the pda is small, the neonate/infant/child is often asymptomatic. However, if the PDA is larger then they may be symptomatic; state some potential symptoms of PDA
* SOB
* Difficulty feeding
* Poor weight gain/failure to thrive
* Frequent lower respiratory tract infections
30
A large PDA can cause signs of ____ soon after birth
**Heart failure**
*\*Smaller PDAs could also go undetected until adulthood in which they may still be asymptomatic or may present with signs of heart failure*
31
Discuss potential consequences of a PDA (in regards to how it can impact the heart)
* Blood flows from aorta to pulmonary arteries
* Increased blood flowing through pulmonary arteries
* Increases pressure in pulmonary vessels causing **pulmonary hypertension**
* Leads to right heart strain and **right ventricular hypertrophy**
* Increased blood flowing through pulmonary vessels means there is in**creased blood returning to left side** of heart leading to **left ventricular hypertrophy**
* Can therefore lead to heart failure
32
How is a PDA diagnosed?
* Echocardiogram to confirm diagnosis:
* Use of doppler flow studies can assess size & characteristics of L to R shunt
* Also useful for assessing impact of PDA on the heart
33
Discuss the management of a PDA
* **Indomethacin or ibuprofen** can be given to neonate to inhibit prostaglandin synthesis and promote closure
* **Typically monitored until 1yr of age** using echocardiograms; after 1yr highly unlikely it will close spontaneously so **trans-catheter or surgical closure** is done
* If s**ymptomatic or evidence of heart failure**, surgical correction is done **earlier**
* If associated with a**nother congenital heart condition** you may r**equire the PDA to remain open** therefore may give **prostaglandin E1** until surgical repair of other abnormalities is appropriate
34
What is a VSD?
How common are they?
Ventricular septal defects are congenital **holes in the septum between the two ventricles**; size can vary from a tiny whole to the absence of an entire septum (meaning there is one large ventricle).
**Most common type of congenital heart defect**
35
VSDs may be detected in antenatal scans or if a murmur is heard during newborn examination; however, it may also present later in infancy/childhood. State some symptoms of VSD in neonates/infancy/childhood
The larger the VSD, the sooner the symptoms are noted. Moderate size usually obvious by 2-3 months as pulmonary vascular resistance increases due to shunting.
* Poor feeding
* Failure to thrive
* Sweating *(due to increase sympathetic activity as compensation for decreased CO)*
* Heart failure *(tachypnoea, tachycardia, pallor, hepatomegaly)*
* Frequent chest infections
36
Congenital VSDs can occur in isolation but are often associated with genetic conditions/syndromes; state some examples
* Genetic conditions/synrdromes:
* Down's syndrome
* Turner syndrome
* Edward syndrome
* Patau syndrome
* cri-du-chat syndrome
* Holt-Oram syndrome
* Maternal diabetes mellitus *(not gestational diabetes)*
* Maternal rubella infection
* Fetal alcohol syndrome
* Family history
*\*Acquired causes include post-MI*
37
The VSD murmur is ________ in smaller defects
VSD murmur is **LOUDER** in smaller defects
38
What murmur is heard when there is a VSD and where is it heard best?
What else may you find on examination?
* **Pan-systolic (holosystolic) murmur**
* **Left lower sternal border (3rd and 4th ICS)**
* May also find systolic thrill on palpation at lower left sternal border
*\*NOTE: if a neonate has large VSD*
39
VSDs can occur in two parts of the ventricular septum; describe these
* Peri-membranous defects: *occur in upper, membranous part near the valves (70%)*
* Muscular defects: *occur in lower, muscular section (20%)*
40
State some differentials (other than VSD) for a pan-systolic murmur
* Mitral regurgitation
* Tricuspid regurgitation
41
Discuss the management of VSDs
* Referral to **paediatric cardiologist** *(management is highly specialised)*
* **Small VSDs** with n**o evidence of pulmonary hypertension or heart failure** can be **monitored** as they 50% of VSDs close spontaneously
* **Moderate to large VSDs** usually result in a **degree of heart failure** in first few months hence require:
* **Nutritional support** *(e.g. NG feeds)*
* **Medication for heart failure** *(e.g. diuretics, ACE inhibitors, digoxin)*
* **Surgery** *(transcatheter closure or open heart surgery)*
42
Discuss potential consequences of a VSD (in regards to how it can impact the heart
* Blood flows left to right through VSD
* Leads to increased blood volume in right side of heart and in the pulmonary vessels
* Increases blood volume in RV causes RV strain and hypertrophy which may lead to right sided heart failure
* Increased blood volume in pulmonary vessels can lead to pulmonary vessel hypertrophy and consequently pulmonary hypertension- this will increase RV strain
* Eisenmenger sydnrome may occur
43
State some potential consequences of VSDs
* Infective endocarditis *(often given prophylactic abx before procedures)*
* Eisenmenger syndrome
* Right sided heart failure
* Pulmonary hypertension
* Aortic regurgitation *(due to prolapse of valve leaflet through defect)*
*\*SIDE NOTE: pregnancy is contraindicated in pulmonary hypertension as it has 30-50% risk mortality*
44
What is coarctation of the aorta?
Narrowing of the aortic arch, usually around the ductus arteriosus region. Severity can vary from mild to severe.
45
State some risk factors for coarctation of the aorta
Male
* Genetic conditions:
* Turner's syndrome
* DiGeorge syndrome
* Hypoplastic left heart syn
46
Describe the effect of coarctation of the aorta on the blood pressure both distal and proximal to the narrowing
* Distal: pressure decreases
* Proximal: pressure increases
47
State some symptoms of coarctation of the aorta
State some signs of coarctation of the aorta
Often only indication of coarctation in neonate are:
* **Weak femoral pulses**
* **High blood pressure** in limbs supplied from arteries **before** narrowing, l**ower blood pressure** in limbs supplied from arteries **after**
* May be a **systolic murmur in left infraclavicular area and below left scapula**
May have symptoms and signs such as:
* **Poor feeding**
* **Grey & floppy baby**
* **Tachypnoea & increased work of breathing**
Over time may develop….
* **Left ventricular heave** *(due to left ventricular hypertrophy)*
* **Underdeveloped left arm** if there is reduced flow to the left subclavian artery
* **Underdevelopment of legs**
48
What investigations are required for coarctation of aorta?
* ECG
* CXR
* Echocardiogram
49
When deciding how to manage coarctation of the aorta, we talk about mild-moderate/non-critical and severe/critical coarctation; what is meant by each?
_Mild-moderate/non-critical_
* May be asymptomatic or present with hypertension
* Collateral vessels often enlarge & allow blood to bypass narrowed segment
_Severe/critical_
* Shortly after birth neonate presents with low cardiac output (heart failure) and potentially shock once ductus arteriosus closes
50
Discuss the management for coarctation of aorta
* If **mild, pts can live symptom free until adulthood without requiring surgical input**
* In critical coarctation, will require **emergency surgery** shortly after birth and **prostaglandin E** can be given to **keep ductus arteriosus open** while waiting for surgery
*\*keeping ductus arteriosus open allows some blood to flow through the duct into the systemic circulation distal to the coarcation*
51
State some potential complications of coarctation of the aorta
* Heart failure
* Systemic hypertension
* Aortic aneurysm
* Coronary artery disease *(more likely if delayed repair due to systemic hypertension)*
52
What is congenital aortic valve stenosis?
**Born with a** **narrow aortic valve**; severity of stenosis varies and the severity determines the symptoms. Their aortic valve may have **one, two, three or four leaflets**. It tends to be a **progressive condition that worsens over time.**
53
Mild congenital aortic stenosis can be be completely asymptomatic; however, more severe stenosis can cause symptoms. State some potential symptoms
If **severe, may present with heart failure in first few months** of life.
If less severe may present later in childhood with:
* **Fatigue**
* **Shortness of breath**
* **Dizziness**
* **Fainting**
* **Symptoms worse on exertion**
54
What murmur would you hear in congenital aortic stenosis?
Where would you hear it loudest?
* Ejection systolic crescendo-decrescendo murmur that radiates to the carotids
* Loudest at aortic area (2nd ICS, right sternal border)
55
Alongside the characteristic murmur of aortic stenosis, what other signs may you find on examination of pt with aortic stenosis?
* Ejection click just before murmur
* Palpable thrill during systole
* Slow rising pulse
* Narrow pulse pressure
56
What is the gold standard investigation to diagnose congenital aortic stensosis?
Echocardiogram
57
Congenital aortic stenosis tends to be a progressive condition that worsens over time hence pts need regular follow up under paediatric cardiologist. What investigations will be used to monitor the condition?
* ECGs
* Echocardiograms
* Exercise testing
58
Discuss the management of congenital aortic stensosis
* Referral & follow up by **paediatric cardiologist**
* If **significant stenosis, may need to restrict activities**
* Surgical options:
* **Percutaneous balloon aortic valvuloplasty** *(go in via femoral artery and use balloon to dilate)*
* **Surgical aortic valvotomy**
* **Valve replacement**
59
State some potential complications of congenital aortic stenosis
* Left ventricular outflow obstruction
* Heart failure
* Ventricular arrhythmia
* Bacterial endocarditis
* Sudden death, often on exertion
60
What is congenital pulmonary valve stenosis?
**Born with narrow pulmonary valve**; may be due to leaflets becoming **thickened or fused.**
61
Congenital pulmonary valve stenosis can occur without any associations; however, it can be associated with some other conditions. State some examples
* Tetralogy of Fallot
* William syndrome
* Noonan syndrome
* Congenital rubella syndrome
62
Congenital pulmonary stenosis is often asymptomatic and discovered incidentally during examination; however, more severe congenital pulmonary stenosis can cause symptoms. State some potential symptoms
* Fatigue on exertion
* Shortness of breath
* Dizziness
* Fainting
63
What murmur would you hear in congenital pulmonary stenosis?
Where would you hear it best?
* Ejection systolic murmur
* Pulmonary area (2nd ICS, left sternal border)
64
Alongside characteristic murmur, what other signs may you find in congenital pulmonary stenosis?
* Palpable thrill in pulmonary area
* Right ventricular heave *(due to RV hypertrophy)*
* Raised JVP with giant a waves
65
What is the gold standard investigation for diagnosing congenital pulmonary stenosis?
Echocardiogram
66
Discuss the management of congenital pulmonary stenosis
* If mild & asymptomatic, no intervention required just monitored by cardiologist
* If significant stenosis and/or symptomatic then **percutaneous** **balloon valvuloplasty** is first line
* If percutaneous balloon valvuloplasty not appropriate then **open heart surgery can be performed (valvotomy or replacement)**
67
What are the 4 abnormalities in Tetralogy of Fallot?
* Ventricular septal defect
* Overriding aorta *(aortic valve/entrance to aorta is placed further to the right than normal)*
* Pulmonary valve stenosis
* RV hypertrophy
68
State some risk factors for Tetralogy of Fallot
* Rubella infection
* Increased age of mother (\>40yrs)
* Alcohol consumption during pregnancy
* Warfarin use during pregnancy
* Diabetes mellitus in mother (not gestational diabetes)
* Male
* FH of congenital heart conditions
69
Tetralogy of Fallot can be acyanotic or cyanotic; the degree of _____ mostly determines whether it is cyanotic or not?
Explain how Tetralogy of Fallot can lead to cyanosis.
**Degree of pulmonary stenosis** mostly determines whether it's acyanotic or cyanotic. Greater degree of pulmonary stenosis, greater risk of cyanosis.
The aorta is overriding (placed further to right than normal) above the VSD; consequently, when the RV contracts and sends blood upwards the aorta is in the direction of travel of that blood (due to it being more to the right and VSD being present) hence some deoxygenated blood enters the aorta from the right side of the heart. The degree of pulmonary stenosis is what dictates how much deoxygenated blood goes into aorta as the greater the pulmonary stenosis, the greater the RV strain. RV strain causes RV hypertrophy which results in pressures in the right side of heart increasing and blood taking a ‘more left’ direction. More deoxygenated blood entering the aorta, greater the risk of cyanosis.
*\*Eventually Eisenmenger syndrome may occur*
70
When is Tetralogy of Fallot usually detected?
* During antenatal scans before baby is born
* When born, may hear the ejection systolic murmur of pulmonary stenosis
71
What is the gold standard investigation for diagnosing Tetralogy of Fallot?
What other investigations may you do?
Gold standard =Echocardiogram *(doppler helps assess severity of the abnormality & shunt)*
*Others:*
* *ECG*
* *CXR (may see ‘boot shaped’ heart due to RV thickening)*
72
What is gold standard investigation for diagnosing Tetralogy of Fallot?
* **Echocardiogram**
* Others include:*
* *ECG (may show right axis deviation & RV hypertrophy)*
* CXR *(boot shaped heart)*
73
There are 3 subcategories for Tetralogy of Fallot:
* Mild (pink) TOF
* Moderate-severe (cyanotic) TOF
* Extreme TOF
… describe each in regards to presentation
* **Mild (pink) TOF:** *mild PS and RVH and are usually asymptomatic at start. Disease progresses as child & heart grows so by age of 1-3yrs often develop cyanosis*
* **Moderate-severe (cyanotic) TOF:** *present with heart failure symptoms, cyanosis, respiratory distress etc… within first few weeks of life*
* **Extreme TOF:** *can be further divided into TOF with pulmonary atresia (10%) or absent pulmonary valves (6%). These are duct dependent as only way deoxygenated blood can flow to lungs is through PDA. If undetected in antenatal scans present within first few hours of life*
\*\*NOTE: typically presents around 1-2 months
74
Discuss how pts with Tetralogy of Fallot present; think about differences in presentation for mild and severe cases
**Severe cases will present with heart failure before 1yr of age**; signs & symptoms may include:
* **Cyanosis**
* **Clubbing**
* **Poor feeding**
* **Poor weight gain**
* **Ejection systolic murmur** heard loudest in pulmonary area
* **Tet spells**
**Milder cases** may present with **symptoms & signs of heart failure later in childhood**
75
What are ‘tet spells’?
* **Cyanotic episodes**
* Child will also become **irritable and hyperpnoea (increased resp rate & deeper breathing)**. May lead to **reduced consciousness, seizures or death in severe cases**
* Often precipitated by **waking** *(as often kick their legs)***, physical exertion, crying or pooing**
* Due to **intermittent worsening of R to L shunt**
* R to L shunt worsens when either p**ulmonary vascular resistance increases** or **systemic resistance decreases** as Blood always takes path of least resistance
*Example: when exercising a lot of CO2 is generated. CO2 is a vasodilator hence causes systemic vasodilation and decreases systemic vascular resistance. Increases R to L shunting of blood meaning more deoxygenated blood enters aorta and less deoxygenated blood enters pulmonary arteries to go to lungs*
76
Discuss the management of Tet spells; think about non-medical management (e.g. what parents/children can do at home) and medical management
_Non-medical management_
* **Positioning** to **increase systemic vascular resistance**:
* Older children should **squat**
* Younger children should be positioned with **knees to chest**
_Medical management_
* **Oxygen**
* **Beta blockers:** *relax RV and improve flow to pulmonary vessels*
* **IV fluids:** *increase pre-load to increase volume of blood flowing to pulmonary vessels*
* **Morphine:** *decrease respiratory drive to result in more effective breathing*
* **Sodium bicarbonate:** *buffer any metabolic acidosis that occurs*
* **Phenylephrine infusion:** *increase systemic vascular resistance*
77
Discuss the management of Tetralogy of Fallot
* In neonates with severe TOF **give prostaglandin E1 or E2 infusion** to keep ductus arteriosus open *(to allow some blood to flow from aorta to pulmonary arteries)*
* **Surgical repair via open heart surgery**
78
Discuss the prognosis of TOF
* Depends on severity
* Prognosis is poor without treatment
* 90% of pts who have corrective surgery live into adulthood. Require life-long follow up due to risk of long term complications
* Tet spells can be fatal
79
State some potential complications of corrective surgery for TOF
* Pulmonary regurgitation
* Arrhythmias
* Impaired exercise tolerance
* Sudden cardiac death
80
State some potential complications of TOF if left untreated
* Polycythaemia
* Congestive cardiac failure
* Infective endocarditis
* Stroke
* Death *(up to 25% in first year of life)*
81
Summary of TOF
82
What is transposition of the great arteries?
**Attachments of the aorta and pulmonary trunk to the heart are swapped/transposed**; RV pumps blood into aorta and LV pumps blood into pulmonary vessels.
83
State some other congenital heart defects transposition of the great arteries is associated with
* VSD
* Coarctation of arota
* Pulmonary stenosis
84
State some risk factors for transposition of the great arteries
* Increasing maternal age (\>40yrs)
* Rubella infection
* Maternal diabetes mellitus (not gestational diabetes)
* Alcohol consumption in pregnancy
85
Explain why transposition of the great arteries is not a problem in utero
* Gas and nutrient exchange happens at placenta hence not necessary for blood to flow to lungs
* Oxygenated lungs flows from placenta, umbilical vein, ductus venosus, IVC, RA. Most then flows through foramen ovale into LA, LV and pulmonary arteries. Some flows into RV and then into aorta. Ductus arteriosus shunts blunt from pulmonary arteries into aorta. Hence, enough oxygenated blood still entering aorta.
86
Explain why transposition of the great arteries as an **_isolated defect is not compatible with life_**
* Two separate parallel circulations
* Deoxygenated blood enters RA, goes into RV, then goes into aorta to be pumped around body then returns to RA
* Oxygenated blood enters LA, goes into LV, then goes into pulmonary arteries to lungs then back into LA via pulmonary veins
No way of getting oxygenated blood around body and getting deoxygenated blood to lungs to be oxygenated; therefore **not compatible with life.**
87
In order for transposition of the great arteries to be compatible with life a shunt between systemic and pulmonary circulation is necessary; state 3 shunts that would allow immediate survival
* Patent ductus arteriosus
* ASD
* VSD
88
When is transposition of the great arteries usually detected?
* **Usually detected during antenatal scans** *(can then closely monitor and ensure she gives birth in hospital capable of managing the condition after birth)*
* If not detected antenatally, it will present with cyanosis at birth or within a few days; a PDA or VSD can compensate initially by allowing mixing of blood
89
If TGA not detected antenatally, it will present with cyanosis at birth or within a few days; what other symptoms & signs may the neonate have?
Symptoms & signs of heart failure as pulmonary blood flow increases if large VSD present:
* Tachypnoea
* Tachycardia
* Poor feeding
* Poor weight gain
* Sweating
* Prominent RV heave
* Murmur (either of VSD or PDA)
* Loud single S2
90
Echocardiogram is gold standard for diagnosing TGA; state some other investigations you could do and what you may find
* ECG: ‘egg on a string’
* Capillary blood gas: metabolic acidosis with increased lactate due to anaerobic respiration due to lack of oxygen
* Low oxygen saturations on pulse oximetry *(may be discrepancies between upper & lower limbs)*
91
Discuss the management of TGA
_Emergency/immediate procedures to allow mixing of blood_
* Prostaglandin E1 infusion to keep ductus arteriosus patent
* Atrial balloon septostomy
_Definitive & long term management_
* Surgery: arterial switch operation (usually before 4 weeks of age) whilst on cardiopulmonary bypass
* Long term follow up
* Counselling if wish to get pregnant in future
92
State some potential consequences of TGA
* Neopulmonary stenosis
* 'Neoaortic regurgitation
* Neoaortic root dilation
* Coronary artery disease
* Obstructed coronary arteries *(most common cause of morbidity & mortality after arterial switch operation. Incidence of ischaemia, MI and death is highes in first 3/12 after ASO)*
* Neurodevelopmental abnormalities
93
Discuss the prognosis of TGA
* Prognosis depends on complexity of TGA and how it was repaired
* Psot-surgical correction 90% survival at 20yrs
* Low gestational age, high pre-op lactate are indicators of poor developmental outcome
94
What is tricuspid atresia?
**Absence of tricuspid valve associated with hypoplasia of RV.** Hypoplasia of RV occurs due to absence of inflow into RV due to absence of tricuspid valve.
95
What **other congenital cardiac abnormality must be present** in tricuspid atresia?
What other congenital cardiac abnormality is **present in the vast majority of cases?**
* **ASD must be present** to allow blood from **RA to flow into LA** *(allow systemic venous return out of heart)*
* **Vast majority have VSD**; size of VSD will affect size/development of RV
96
Tricuspid atresia is associated with transposition of great arteries; true or false?
True; 70% have normal great arteries and **30% have transposed great arteries**
97
Discuss how tricuspid atresia may present
* Poor feeding
* Progressive cyanosis
* Heart failure (rare unless late presentation or inter-atrial communication inadequete)
* Murmurs (due to VSD, PDA etc..)
98
Discuss the management of tricuspid atresia
_Initial treatments to allow adequate mixing of blood_
* IV prostaglandin E1 to keep ductus arteriosus patent
* Balloon atrial septostomy
_Definitive/long term_
* Variety of surgical procedures at different ages. The definitive procedure, Fontan procedure, at 3-4yrs of age
99
Explain why transposition of great arteries as an **_isolated defect_** is not viable with life
* If it is an isolated defect there are two separate circulations
* Deoxygenated blood enters RA, goes into RV, then goes into aorta hence deoxygenated blood is circulated around body
* Oxygenated blood enters LA, goes into LV, then goes into pulmonary circulation and comes back into LA
Cannot oxygenate blood and then send it around body so
100
What is hypoplastic left heart syndrome?
Underdevelopment of structures on left side of heart; it can affect a number of structures including:
* LV (underdeveloped and too small)
* Mitral valve (too small or not formed)
* Aortic valve (too small or not formed)
* Ascending aorta (underdeveloped or too small)
Often babies have ASD
101
What other congenital heart defects must be present for hypoplastic left heart syndrome to be viable?
* Patent foramen ovale or ASD: *allow oxygenated blood returning to LA to shunt into RA then to RV then to pulmonary arteries*
* Patent ductus arteriosus: *allow mixed blood in pulmonary arteries to shunt into aorta via PDA (pressure in R \> pressure in L due to hypoplastic heart and decreased volume???)*
102
Like many other congenital heart defects, hypoplastic left heart syndrome may be picked up during antenatal scans. If not detected, describe how they will present
* Might be okay for first few days whilst PDA and foramen ovale remain open
* Once they close they will develop signs & symptoms of heart failure (cyanotic, difficulty breathing, tachycardia). May hear murmur of ASD or PDA.
103
Discuss the management of hypoplastic left heart syndrome
_Immediate/emergency treatments to allow mixing of blood_
* IV prostaglandin E1 to keep ductus arteriosus patent
_Surgery a few days after birth_
* Norwood procedure *(or hybrid if not suitable)*
* \*Norwood procedure involves separating the main pulmonary artery from the R and L branches. Then join the main pulmonary artery to the aorta. RV now supplies the aorta with mixed blood (as the ASD remains). A shunt is placed between the aorta and branches of pulmonary artery to provide mixed blood to the lungs. Hybrid uses a stent to keep PDA open and places small bands around left and right pulmonary arteries to reduce blood flow to lungs.*
104
What is pulmonary atresia?
**Pulmonary valve has not formed therefore blood cannot flow from RV to the pulmonary artery.** Need either ASD or VSD and a PDA; to allow blood from right side to flow to left side and be pumped out of heart then need PDA to allow blood to go to pulmonary arteries
Two types:
* _Pulmonary atresia with intact ventricular septum:_ *very little blood flows into RV hence remains very small and underdeveloped*
* _Pulmonary atresia with VSD:_ *allows some blood to flow into RV from the LV so RV not as small or underdeveloped as with an intact ventricular septum*
\*image shows without VSD
105
When will neonates with pulmonary atresia show signs & symptoms?
At birth or very soon after!
106
Discuss the management of pulmonary atresia
* Immediate/emergency transfusion of prostaglandin E1 to keep ductus arteriosus open
* Surgery within first few days then numerous corrective surgeries afterwards
107
What does TAPVR stand for?
What is TAPVR?
* **Total anomalous pulmonary venous return**
* **Pulmonary veins don't connect to the LA like usual;** this can be partial/**PAPVR** (not all of veins have abnormal connection) or **TAPVR** (all veins have abnormal connection).
* Examples of abnormal connections:
* **Supracardiac:** *connected to the SVC*
* **Cardiac:** *connected to RA*
* **Infracardiac**: *connected to veins of liver & IVC*
* **_Have to have a patent foramen ovale or ASD_** to allow mixing of oxygenated and deoxygenated blood
108
Discuss the management of TAPVR
* Oxygen
* Prostaglandin E1 infusion used in some types of TAPVR
* Definitive treatment= surgical correction *(how soon depends on the defects/structural abnormalities and how sick the child is)*
109
What is truncus arteriosus?
What is the management?
* Blood vessel coming out of the heart in the developing baby fails to separate completely during development, leaving a c**onnection between the aorta and pulmonary arter**y. Instead of having both an aortic & pulmonary valve they have a **single truncal valve**. **Truncal valve is often thickened & narrowed** which can impair blood flow from heart as well as leaking blood back into heart (regurgitation). There is **usually a VSD** aswell.
* Surgery (usually in first few months of life but depends how unwell child is): *close VSD, use original single blood vessel to create a new aorta and use an artificial tube to connect RV to the pulmonary arteries*
110
What are atrioventricular septal defects?
There are **abnormal connections between left and right side of heart due to hole(s) in either the atrial septum, ventricular septum or both**. The **AV valves may also not be formed correctly.**
* _Complete AVSD_: *large hole in centre of heart allowing blood to flow between all 4 chambers of heart. One common AV valve (as opposed to two) and this common valve may not have formed correctly.*
* _Partial AVSD_: *a hole in either the atrial or ventricular septum near the centre of heart. Usually has both AV valves but one of them (usually the mitral) regurgitates.*
\*managed surgically
111
What is Ebstein's anomaly? Include:
* Defect
* How this defect affects flow
* What other abnormalities associated with
* **Tricuspid valve is set lower in right side of heart towards the apex** causing a **bigger RA and a smaller RV. Valve also leaks/regurgitates.**
* Leads to **poor flow from RA to RV** and **poor flow to pulmonary vessels**
* Often **associated with ASD** (with _right to lef_t shunt); blood then bypasses lungs leading to **cyanosis.** And associated with **Wolff-Parkinson-White syndrome.**
112
Use of which medication in pregnancy may cause Ebstein's anomaly?
Lithium
113
Why may pts with Ebstein's anomaly and an associated ASD present a few days after birth?
* If have ASD, there will be a R to L shunt
* Meaning deoxygenated blood bypasses lungs (where it would normally be oxygenated)
* In first few days of life, whilst ductus arteriosus is still open, this is not an issue as mixed blood in aorta can be shunted to the pulmonary vessels via the PDA to get oxygenated
* When ductus arteriosus closes, the deoxygenated blood is not getting oxygenated in lungs hence they become symptomatic
114
State some presenting features of Ebstein's anomaly
* Heart failure
* Oedema
* Gallop rhythm
* SOB
* Tachypnoea
* Cyanosis
* Sweating
* Poor feeding
* Collapse
* Cardiac arrest
115
Discuss the medical management of Ebstein's anomaly
* Medical management:
* Treating arrhythmias (e.g. beta blocker)
* Treating heart failure (e.g. diuretics)
* Prophylactic abx to prevent infective endocarditis
* Definitive management is surgical correction
116
For Eisenmenger syndrome, discuss:
* What it is
* Three underlying defects that can cause Eisenmenger syndrome
* How long it takes to develop
* Which population are at risk of quicker development of Eisenmenger syndrome
* **Reversal of a left-to-right shunt** in a congenital heart defect due to **pulmonary hypertension**
* Three defects: **ASD, VSD and PDA**
* If large shunt then can develop after 1-2yrs or may not develop until adulthood if smaller shunt
* **Can develop more quickly in pregnancy** hence women with hole in heart need an echo and close monitoring by cardiologist during pregnancy
117
Describe the pathophysiology of Eisenmenger syndrome
* Normally blood shunts L to R due to pressure on L being greater *(in this case blood still travels to lungs to get oxygenated so not cyanotic)*
* Increased blood flow to R side and pulmonary vasculature leads to remodelling of pulmonary vasculature and pulmonary hypertension
* When pulmonary pressure \> systemic pressure blood now shunts R to L
* Causes deoxygenated blood to bypass lungs and enter body causing cyanosis
118
Why do pts with Eisenmenger syndrome get polycythaemia?
What is a potential consequences of polycythaemia?
* Bone marrow's response to hypoxia is to increase RBC production to increase Hb in blood
* Increased blood viscosity therefore **increased risk of clots**
119
What might you find on examination of pt with Eisenmenger syndrome?
_Findings associated with pulmonary hypertension_
* RV heave *(RV hypertrophy due to increased pulmonary resistance)*
* Loud P2 *(due to forceful shutting of pulmonary valve)*
* Raised JVP
* Peripheral oedema
_Findings associated with underlying septal defect_
* Atrial septal defect: ***mid-systolic***, ***crescendo-decrescendo*** murmur loudest at the upper left sternal border
* Ventricular septal defect: ***pan-systolic murmur*** loudest at the left lower sternal border
* Patent ductus arteriosus: ***continuous crescendo-decrescendo*** “***machinery***” murmur
* Arrhythmias
_Findings related to R to L shunt & chronic hypoxia:_
* Cyanosis
* Clubbing
* Dyspnoea
* Plethoric complexion *(red complexion due to polycythaemia)*
120
Discuss the management of Eisenmenger syndrome
* Prevention: underlying defect should be managed optimally or surgically corrected to prevent development of Eisenmenger syndrome
* Once developed, only definitive treatment is heart-lung transplant
* Medical management:
* Oxygen
* Sildenafil for pulmonary hypertension
* Medications for arrhythmias
* Venesection to treat polycythaemia
* Anticoagulants to prevent and treat thrombosis
* Prophylactic abx to prevent infective endocarditis
121
Discuss the prognosis of Eisenmenger syndrome
* Reduces life expectancy by 20yrs
* Main causes of death:
* Heart failure
* Thromboembolism
* Haemorrhage
* Infection
* Mortality can be up to 50% in pregnancy
