The cardiovascular disease - congenital heart disease and hypertension Flashcards
Describe the foetal circulation
Oxygenated blood is carried from the placenta to the right side of the heart via the following route: placenta –> umbilical vein –> ductus venous –> inferior vena cava –> right atrium
From the right atrium, the oxygenated blood can take three different routes:
1. Via the foramen oval: This makes up the majority of blood flow. Blood travels from right atrium –> foramen oval –> left atrium –> left ventricle –> aorta
- Via the ductus arteriosus: this makes up the majority of blood flow. Blood travels from right atrium –> right ventricle –> pulmonary artery –> ductus arteriosus –> aorta. Blood flows through the ductus arteriosus instead of the lungs because the systemic vascular resistance (SVR) has a lower resistance than the pulmonary vascular resistance (PVR)
- Via the foetal lungs: only a tiny amount of blood is left to circulate through the immature lungs
Describe the changes in circulation at birth
After birth, the placenta no longer supplies blood to the baby. As the baby takes its first breath, the pulmonary vascular resistance (PVR) drops significantly lower than the SVR, then progressively over 4-6 weeks. Blood now experiences minimal resistance from the pulmonary vasculature, and this starts flowing through the lungs
The ductus arteriosus will close and form the remnant ligament arteriosum
The oval foramen flap closes with increased atrial pressure (the entry of blood into the left atrium through the pulmonary veins will also push the floppy septum premium up against the septum secundum, thereby closing the foremen over). This then forms the fossa ovalis
In utero, left and right chamber pressure are equal. After birth, right-sided pressure gradually falls over several weeks due to the the fall in PVR
What are the five general clinical features of congenital heart disease
mnemonic ‘CHAMP
- Cyanosis
- Heart failure
- Arrhythmia
- Murmur
- Pulmonary hypertension
Women with complex CHD who are planning on getting pregnant are, despite treatment are at higher risk of complications during pregnancy.
Describe how these patients should be managed
- They should undergo specialist assessment to plan their care
- Early conversations
- Young women: contraception, pregnancy risks, risks of assisted reproductive therapy
- Foetal risks: loss, pre-term
- Risks for child: loss of parent in child hood - In severe individuals with severe CHDs, it may be advisable to avoid pregnancy altogether e.g., contraception
- Foetal echocardiography should be performed in the 26th week of pregnancy to exclude foetal abnormality
Give 4 overall simple predictions of maternal risk
- Prior cardiac event (TIA, stroke, arrhythmia, heart failure)
- NYHA > grade II pre-pregnancy
- Left heart obstruction - mitral or aortic stenosis, CoA
- LVEF < 40%
Give 3 risk scores used in pregnancy
- WHO
- RPAC
- CARPREG 2
Describe the psychosocial issues involved in congenital heart disease
- Ill health and poor schooling - employment difficulties
- Difficulty with insurance
- Self-image: scar on chest
- Housing, prescription charges, driving
- Lifelong follow up, tests, spectre of intervenetion
- Reduced QoL
What is atrial septal defect (ASD)?
ASD refers to communication between the left and right atria
Describe the epidemiology of ASDs
ASDs are mostly sporadic, with certain risk factors (e.g., maternal alcohol a abuse)
A small percentage is familial
Describe the pathophysiology of atrial septal defect
Most commonly arises because of the failure of the foramen ovale to close, secondary to a defect in the osmium secundum
As blood comes into the left atrium there will be a low resistance in the left ventricle –> a proportion goes back into the right atrium via shunt (but depends on size of shunt and pressure gradient) –> leads to right atrial dilatation, right ventricle dilation and pulmonary artery dilation –> increased pulmonary blood flow
AKA pre-tricuspid shunt (occurs before tricuspid valve)
Clinical features of atrial septal defect
a) Symptoms
b) Signs
a)
- Usually asymptomatic
- Palpitations in AF
- Signs of heart failure: fatigue, breathlessness, peripheral oedema, hepatomegaly
b)
- Prominent RV impulse
- Murmur: a soft ejection systolic murmur best heard at the upper left sternal edge –> due to increase blood flow past the pulmonary valved
- Fixed (in all stages of respiration) widely split soft S2
- Late features: arrhythmia (AF), heart failure (due to right heart dilatation)
Describe the presentation and symptoms of small ASD in
a) Neonate
b) Young child
c) Adult
a) Nothing
b) Incidental murmur
c) Paradoxical embolus, stroke
Describe the presentation and symptoms of medium ASD in
a) Neonate
b) Young child
c) Adult
a) Nothing
b) Recurrent pneumonia, poor growth, incidental murmur
c) Exercise intolerance, recurrent pneumonia, atrial arrhythmia
Describe the presentation and symptoms of large ASD in
a) Neonate
b) Young child
c) Adult
a) Nothing
b) Exercise intolerance, fatigue, poor growth
c) Atrial arrhythmia, tricuspid regurgitation, heart failure, pulmonary hypertension
Describe the 1st line and 2nd line investigations of ASD
1st line
- Echocardiography
2nd line
- ECG
Describe the ECG changes in ASD
Not diagnostic, but can show tall P waves (P-pulmonale) representing right atrial enlargement of partial RBBB
Describe the CXR signs in an older child or adult
- Cardiomegaly
- Dilation of the right atrium
- Dilation of the right ventricle
- Prominent main pulmonary artery
- Increased pulmonary vascular markings
Describe the management of ASD
Management depends on the extent of the shunt
- Observation: no surgical intervention is necessary if there is a small ASD as the majority close spontaneously by 2 years. Intervention is indicated if the condition worsens
- Transcatheter closure: most defects can be closed by percutaneous transcatheter closure but very large ASDs or premium ASDs require surgical closure
Give 3 indications for closure in ASDs
- Large ASD
- Primum ASD
- Heart failure
- Symptomatic
- RA and RV enlargement
- Net L to R shunt Qp:Qs > 1.5
- No cyanosis at rest or exercise
- Systolic PA pressure <50% systemic pressure
- PVR < 1/3 SVR
What is a ventricular septal defect?
A ventricular septal defect (VSD) refers to communication between the left and right ventricle
Describe the pathophysiology of a ventricular septal defect
When the left ventricle contracts, blood goes through aortic valve –> the shunt causes a lower pressure in right ventricle than aorta –> blood flow goes from left to right ventricle via shunt and into pulmonary artery –> the extra blood flow goes into the lungs, back into the left atrium and then left ventricle –> some will go back again through the pulmonary artery –> high pulmonary flow leads to pulmonary artery dilation –> resistance in lungs (pulmonary vascular resistance) stays low so increasing loading of left atria and ventricle chamber –> left heart (atrial and ventricular) dilatation
Describe the presentation and symptoms of small VSD in
a) Young child
b) Adult
a) Incidental murmur
b) Incidental murmur endocarditis
Describe the presentation and symptoms of medium VSD in
a) Neonate
b) Young child
c) Adult
a) > 4 weeks incidental murmur, sweatiness with feeds
b) Poor growth, murmur, frequent chest infections
c) Incidental murmur, endocarditis
Describe the presentation and symptoms of large VSD in
a) Neonate
b) Young child
c) Adult
a) > 4 weeks tachypnoea, poor feeding, failure to thrive
b) Frequent chest infections, exercise intolerance, fatigue, poor growth
c) Breathlessness, fatigue, HF, Pulmonary hypertension
What are the key features of VSD’s?
A small VSD will cause no symptoms
Key features
- Shortness of breath
- Sweating and poor feeding in children
What are the examination findings of a VSD?
Murmur: a pansystolic murmur best heard at the left sternal border. A small VSD produces a louder murmur than large VSDs - this loud murmur is given the name ‘Maladie de Roger’. A thrill is palpable sometimes
Displaced, hyper dynamic apex
Hepatosplenomegaly
Describe the 1st line and 2nd line investigations for VSD
1st line
- Echocardiography
2nd line
- CXR: for moderate to large VSDs
Describe the management of VSDs
Small VSD
- Because small VSDs are haemodynamically insignificant and tend to close spontaneously, conservative management is appropriate for small defects. Echo can be used to assess the likelihood of spontaneous closure
Significant VSDs
- Any complication is an indication for intervention by surgical correction - by either sealing the VSD with a patch or with a percutaneous device
Give 3 indication for VSD closure
- Symptomatic
- LA and LV enlargement
- Net L to R shunt Qp:Qs > 1.5
- No cyanosis at rest or exercise
- Systolic PA pressure <50% systemic pressure
- PVR < 1/3 SVR
What is the main complication from small VSD?
Infective endocarditis (vegetations may appear at the tricuspid valve, opposite or around the defect or on the aortic valve)
Irreversible pulmonary hypertension can develop from 12 months of age and if progressive, may lead to Eisenmenger’s syndrome. Describe Eisenmenger’s syndrome
- Pulmonary blood flow that occurs because of left-to-right shunt can progressively lead to increased pulmonary artery pressures due to increased resistance of blood flow in the lungs, resulting in pulmonary hypertension
- The pulmonary artery pressure and its corresponding right ventricular muscle mass may then eventually become greater than the left-sided pressure, causing a several of the shunt from right to left
-
What are the complications of Eisenmenger’s syndrome?
- Polycythaemia
- Iron deficiency
- Acne, gout, hypertrophic polyarthropathy
- Paradoxical embolus at iv sites
- Individual medial management of vasodilator therapy
- Arrhythmia risks
Describe the prognosis of VSD and Eisenmenger’s syndrome
Prognosis of VSD is very good if treatment is successful. However, if Eisenmenger’s syndrome occurs, most patients will not live past 50 years
Describe the management of Eisenmenger’s syndrome
Supportive treatment e.g., pulmonary vasodilators and prophylactic antibiotics
Heart lung transplant: rarely does due to poor prognosis and organ donation priorities
What is coarctation of aorta (CoA)
A congenital narrowing of the aorta
Describe the pathophysiology of coarctation of the aorta
Unknown mechanism and aetiology
Coarctation represents an increase in after load of left ventricle and poor cardiac output
Name 3 key associations of CoA
- Bicuspid aortic valve
- VSD’s
- Cerebral ‘berry’ aneurysm
- Turner’s syndrome
CoA
a) Symptoms
b) Examination findings
a) Symptoms of heart failure e.g., breathlessness, fatigue, raised JVP, peripheral oedema, ascites, hepatomegaly
b) Radio-femoral or radio-radial delay in adults; reduced or absent femoral pulse in children
Systolic murmur: best heard at the left sternal border but may only be heard upon auscultation of the back
Pressure differences: BP in the upper limb higher than the lower limbs
Saturation difference: higher pre-ductal (circulation supplied before the aortic isthmus e.g., upper limb circulation) than post-ductal (after the aortic isthmus e.g., lower limb circulation) oxygen saturations in neonates
Describe the 1st line and 2nd line investigations for CoA
1st line
- B Arm BP vs leg BP (must measure both arms as L arm usually has a higher BP and will five false reassurance)
- Echocardiograpy
- ECG
- CXR
2nd line
- MRI: suitable in adults or patients with lower thoracic coarctation
ECG findings of CoA
Left ventricular hypertrophy
Complications of CoA?
- Aortic dissection
- Left ventricular failure
- Persistent/recurrent hypertension
Describe the management of CoA
Surgical repair should be performed in early childhood
what is tetralogy of fallot?
Tetralogy of fallot is the combination of the following four defects (PROVe mnemonic)
P - pulmonary stenosis
R - right ventricular hypertrophy
O - overriding aorta
Ve - ventricular septal defect
Describe the pathophysiology of tetralogy od defect
- Believed to occur because of a defect in the bulbar uptime development. All four defects seen in the tetralogy arise as a consequence of an early development fault
- Aetiology is unknown
Describe the clinical features of tetralogy of fallot
Cyanosis
Hypercyanotic spells phenomenon:
- ‘tet spells’ –> describes the phenomenon in which the infant presents increasingly cyanotic , typically crying (this is life threatening and requires immediate intervention)
- Older children may display ‘Fallot sign’ - this describes the phenomenon of a cild squatting down during hypercyantoic spell, because squatting increases systemic resistance and thus eases the effect of the shunt
Ejection systolic murmur (quieter during tet spells)
Describe the investigations for tetralogy of fallot
- Echocardiography
- CXR
What is the definite management of tetralogy of fallot and what age is the preferred to occur at?
Complete surgical repair, preferably before the patient turns 5 years old
What interventions could be done before surgical repair of tetralogy of fallot?
Cyanosis at birth: prostaglandins
Progressive test spells: Propanol prescribed
Progressive cyanosis: a Blalock-Taussig (BT) shunt (is a small, soft tube that lets blood in the body be redirected) will be required before completing surgical repair, and this is normally performed at 6-9 months of age
Constant follow up
Describe the prognosis of Tetralogy of fallot
Prognosis is good after correction
Describe the epidemiology of hypertension
- Prevalence increases with age
What are the two broad aetiology of hypertension
- Primary (95%) - no identifiable cause
- Secondary (5%)
Describe 6 secondary causes of hypertension
Endocrine
- Primary aldosteronism
- Phaemocromocytoma
- Cushing’s disease
- Acromegaly
Renal
- Renovascular disease (e.g., athermatous, fibromuscular dysplasia)
- Intrinsic renal disease (e.g., CKD, AKI, glomerulonephritis)
Coarctation of the aorta
Pregnancy
Obstructive sleep apnoea
Home blood pressure monitors (automated)
a) Advantages
b) Disadvantages
a)
- Ease of use
- Cheap
- Accurate
- Portable
- Print outs
- Error indication
- Mercury free
b)
- Expensive
- Inaccurate
- Poor recordings in certain situations
- Cuff sizes limited
- Difficult to recheck accuracy
- Servicing running costs
- Arrhythmias
- Proteinuria
Clinical features of hypertension
a) Symptoms
b) Signs
a)
- Palpitations
- Angina
- Headaches
- Blurred vision
- New neurology (e.g., limb weakness, paraesthesia)
b)
- New neurology (e.g., limb weakness, paraesthesia)
- Retinopathy
- Cardiomegaly
- Cardiomyopathy
- Arrhythmias
- Proteinuria
Name 3 associated conditions of hypertension
- Cardiovascular disease (coronary, peripheral, cerebral)
- Renal impairment
- Diabetes
Describe the 4 grades of retinal changes pop hypertensive retinopathy classified by the Keith-Wagener Barker (KWB)
Grade 1 - Generalised arteriolar narrowing
Grade 2 - Focal narrowing and arteriovenous nipping (when artery and vein meet and pinch)
Grade 3 - Retinal (flame) haemorrhage, cotton wool spots
Grade 4 - Papilloedema (swelling of optic nerve)
Describe the investigations for hypertension
Bedside
- Observations
- Blood pressure
- Urinanalysis
- Urinary protein creatinine ratio (uPCR)
- ECG
- Direct ophthalmoscopy
Bloods
- FBC
- U&Es
- Fasting glucose
- Cholesterol (CVS risk)
- HbA1c
Special tests
- Ambulatory BP monitoring (ABPM or HBPM)
- Renal USS
- Endocrine tests (e.g., aldosterone: renin ratio, if indicated)
Hypertension definitions
a) Stage 1
b) Stage 2
c) Stage 3
a)
- Clinic blood pressure (BP) is 140/90 mmHg and
- ABPM or HBPM average 135/85 mmHg or higher
b)
- Clinic BP 160/100 mmHg is or higher and
- ABPM or HBPM daytime average is 150/95 mmHg or higher
c)
- Clinic BP is 180 mmHg or higher
- Clinic systolic diastolic BP is 120 mmHg or higher
What is the white-coat effect?
A discrepancy of more than 20/10 mmHg between clinic and average daytime ABPM or average HBPM blood pressure measurements at the time of diagnosis
Name 2 risk assessment scores for hypertension
Framingham risk score
Qrisk2
Describe the assessment of a hypertensive patient
Full history
- Past medical, social, risk factors
Careful examination
- Cardiovascular, peripheral pulses, retinal exam
Formal risk assessment
Key basic tests
- ECG, renal function (including eGFR possibly albumin/creatinine ratio), sodium, potassium, cholesterol, glucose/HbA1c, FBC, urinalysis for protein
- Ambulatory/home blood pressure
Specific tests
- CXR, Echo, renal ultrasound, tests for secondary hypertension, urine albumin/creatinine ratio
Describe lifestyle modification for hypertension
- Weight control
- Dietary salt
- Reduce alcohol
- Exercise
- Smoking cessation (however no clear association with BP)
- Anti-cholesterol
Who should you offer antihypertensive drug treatment to?
- People who have stage 1 hypertension and are aged under 80 and meed identified criteria (diabetes, CV or renal disease, target organ damage)
- Who have stage 2 hypertension at any age
- 10-year CV risk generally needs to be > 10%
If aged under 40 with stage 1 hypertension and without evidence of target organ damage, cardiovascular disease, renal disease, or diabetes. What should you consider?
- Specialist evaluation of secondary causes of hypertension
- Further assessment of potential target organ damage
- Starting at higher doses and using combination antihypertensive treatments
Describe the antihypertensive drug treatment pathway
Step 1: Aged under 55 years or diabetes any age - ACEi (ramipril) / ARBs (Candestartan, Iosartan)
aged over 55 years or people of African or Caribbean family origin of any age - CCB (amlodipine/long acting diltiazem)
Step 2: ACEi + CCB
Step 3: ACEi + CCB + Thiazide-like diuretic e.g., bendrofluazide, indapamide
Step 4: ACEi + CCB + Thiazide-like diuretic + consider further diuretic e.g., spironolactone, alpha or beta-blockers
Target blood pressure for patients:
a) < 80 years
b) ≥ 80 years
a) Clinic BP < 140/90 mmHg / ABPM < 135/85 mmHg
b) Clinic BP < 150/90 mmHg / ABPM < 145/85 mmHg
Malignant hypertension
a) Symptoms
b) Treatment aim
c) Treatment
a) Visual disturbance, headaches, breathlessness, hypertensive encephalopathy
b) IV Nitroprusside, labetalol and glyceryl trinitrate infusions are options
