10 - Cardiology Flashcards
What are some cyanotic and cyanotic congenital heart defects?
- Cyanotic when they have a R to L shunt. Think of the 4 T’s plus Jamie
- Always need shunt and a hole for cyanotic
What investigations should you do if you suspect congenital heart disease?
What is the most common congenital heart defect?
VSD
Shortly followed by ASD
Where are the 3 shunts in the CVS in fetal life?
Done to bypass the pulmonary circulation
Ductus venosus: connects the umbilical vein to the inferior vena cava and allows blood to bypass the liver
Foramen ovale: connects the right atrium with the left atrium and allows blood to bypass the right ventricle and pulmonary circulation
Ductus arteriosus: connects the pulmonary artery with the aorta and allows blood to bypass the pulmonary circulation.
How do the shunts in the CVS close after birth?
The first breaths expands the alveoli, decreasing pulmonary vascular resistance which causes a fall in pressure in the right atrium.
At this point the left atrial pressure is greater than the right atrial pressure, which squashes the atrial septum to cause functional closure of the foramen ovale. Becomes fossa ovalis after a few weeks
Increased blood oxygenation causes a drop in circulating prostaglandins. This causes closure of the ductus arteriosus, which becomes the ligamentum arteriosum.
Immediately after birth the ductus venosus stops functioning because the umbilical cord is clamped and there is no flow in the umbilical veins. The ductus venosus structurally closes a few days later and becomes the ligamentum venosum
What are innocent murmurs in children?
Flow murmurs that occur during systole in children
- Soft
- Short
- Systolic
- Symptomless
- Situation dependent, particularly if the murmur gets quieter with standing or only appears when the child is unwell or feverish
Where is Still’s murmur best heard?
When is a murmur not innocent in a child and what investigations should you do for this?
- Murmur louder than 2/6
- Diastolic murmurs
- Louder on standing
- Other symptoms such as failure to thrive, feeding difficulty, cyanosis or shortness of breath
Send for ECG, CXR, Echocardiogrm
How do you grade the loudness of a murmur?
What are some causes of pan systolic murmurs in children?
- Mitral regurgitation : fifth intercostal space, mid-clavicular line
- Tricuspid regurgitation: (fifth intercostal space, left sternal border)
- Ventricular septal defect: left lower sternal border
- Coarctation of the aorta
What are some causes of ejection systolic murmurs in children?
- Aortic stenosis: second intercostal space, right sternal border
- Pulmonary stenosis: second intercostal space, left sternal border
- Hypertrophic obstructive cardiomyopathy: fourth intercostal space on the left sternal border
- Tetralogy of Fallot
What is a split heart sound, why does it occur and where is it best heard?
- Occurs during deep inspiration
- Negative intrathoracic pressure causes increased venous return to right side of heart so takes longer to empty in systole so pulmonary valve closes slightly after aortic valve
- Best heard in pulmonary area
Where are the following murmurs best heard?
- ASD
- VSD
- PDA
What type of murmur do the following CHD cause?
- ASD
- Tet of Fallot
- PDA
- ASD: mid-systolic, crescendo-decrescendo murmur loudest at the upper left sternal border, with a fixed split second heart sound
- Tet of Fallot: Ejection systolic due to pulmonary stenosis
- PDA: continuous murmur
What acyanotic heart disease can turn cyanotic?
ASD, VSD and PDA if pulmonary pressure increases to greater than left side of heart
Eisenmenger Syndrome
How can you accentuate and diminish certain heart murmurs?
Inspiration: Can hear PS and TR best
Expiration: Augments VSD, MR, AS
Standing: Decreases innocent murmurs
What is a cause of PDA and how may it present? (what murmur)
- Idiopathic or Rubella infection
- Prematurity is risk factor
Why may a PDA not present until adulthood?
May have no murmur
Presents as heart failure
How is PDA diagnosed with investigations and managed?
Investigations
- Echocardiogram with doppler flow to view shunt
- Can also assess LV and RV hypertrophy with this
Management
- Monitor with echos until aged 1 as may close spontaneously
- Give NSAIDs
- If over 1 do trans-catheter or surgical closure
What are some risk factors for atrial septal defects?
- Family history
- Maternal smoking in 1st trimester
- Maternal diabetes
- Maternal rubella
- Maternal drug use e.g. cocaine & alcohol
What are the types of ASD from most to least common?
- Patent foramen ovale
- Ostium secundum defect
- Ostium primum defect
- Sinus venosus defect
- Coronary sinus defect
What are some complications with ASD’s?
- Stroke in the context of DVT
- Arrhythmias
- Atrial fibrillation or atrial flutter
- Pulmonary hypertension and right sided heart failure
- Eisenmenger syndrome
How may an ASD present?
Childhood
- On antenatal scan
- Asymptomatic
- Mid-systolic,crescendo-decrescendomurmur loudest at the upper left sternal border with afixed split second heart sound
- SOB
- Difficulty feeding
- Poor weight gain
- LRTI
Adulthood
- Stroke
- Heart failure
- Dyspnea
Why does ASD have a fixed split heat sound?
Blood is always flowing from left to right atrium so right ventricle always has more blood to pump out than left before pulmonary valve can close
Normal to have a split in inspiration but ASD have split in expiration and inspiration
How is ASD diagnosed?
Diagnosis
- Transthoracic Echocardiogram: gold standard
- ECG: normal in child but may have AF or atrial flutter in adults
- Cardiac MRI
- CXR: look for cardiomegaly
How is ASD managed?
Conservative
- If ASD < 5mm, spontaneous closure should occur within 12 months of birth
- In adults, no signs of right heart failure and a small defect, then monitor every 2 – 3 years with echocardiogram
Definitive management
- Refer to paediatric cardiologist
- Surgical closure if ASD > 1 cm: transcatheter via femoral vein or open chest
- If arrhythmia in adult give anticoagulation whilst awaiting surgery
What are some complications of percutaneous closure of ASD?
- Arrhythmias
- VTE
- AV block
When would you chose open surgical closure for ASD repair over percutaneous?
- TIA / stroke
- Ostium primum defects
- Sinus venous defects
- Coronary sinus defects
What is the most common type of VSD?
Perimembranous
Small ones are found in muscle and often close by age 10
What are some risk factors for VSD?
- Uncontrolled maternal Diabetes Mellitus
- Maternal Rubella infection
- Foetal alcohol syndrome
- Uncontrolled maternal phenylketonuria (PKU)
- A family history of VSD
- Down’s Syndrome (trisomy 21)
- Trisomy 18 syndrome
- Trisomy 13 syndrome
- Holt-Oram Syndrome
How may a VSD present?
- Asymptomatic
- Pan systolic murmur at left lower sternal border
- Poor feeding
- Dyspnoea (sign of congestive heart failure)
- Tachypnoea
- Failure to thrive
- Cyanotic
- Sweating
- Clubbing of fingers
What is the first sign of left sided heart failure in children with a VSD?
Tachypnea
What are some differential diagnoses for a VSD?
- MR
- TR
- ASD
- PDA
What investigations should be done if VSD is suspected?
- Transthoracic Echocardiogram: gold standard
- ECG: may show LV hypetrophy
- CXR: may show cardiomegaly, pulmonary oedema, pleural effusion
- Cardiac CT angiography with ECG-gating
- Genetic testing: especially if dysmorphic
- U+Es: before starting diuretics and ACEi
How should a child with a VSD be managed?
- Good oral hygiene as risk of infective endocarditis
- Monitor if small
- If CHF: Furosemide diuretics, ACEi, increased calorific feeds
- If large: Surgery. In adults do if Qp/Qs (pulmonary-to-systemic blood flow ratio) of 2.0 or more
What are the different surgical procedures used for closure of VSD?
- Transcatheter
- Open heart
What are some complications of VSDs?
Need monitoring for life even if had a repair
- Congestive heart failure
- Growth failure
- Aortic valve regurgitation due to prolapse of a valve leaflet through the defect
- Eisenmenger’s Syndrome
- Frequent chest infections
- Infective Endocarditis
- Arrhythmias
What are AVSDs, who are they common in and how are they treated?
- Down’s syndrome
- Failure of endocardial cushions to fuse correctly
- Need corrective surgery at around 3-6 months of age to prevent pulmonary vascular obstructive disease
How long does Eisenmenger syndrome take to develop?
In ASD, VSD and PDA
1-2 years if large, until adulthood if small
Always monitor pregnant women with hole in the heart as can develop this!
What will you find on examination of someone with Eisenmenger syndrome and why?
Pulmonary hypertension:
- Right ventricular heave: RV contracts against increased pressure in lungs
- Loud P2: loud second heart sound due to forceful shutting of the pulmonary valve
- Raised JVP
- Peripheral oedema
Underlying septal defect:
- ASD: mid-systolic, crescendo-decrescendo murmur loudest at the upper left sternal border
- VSD: pan-systolic murmur loudest at the left lower sternal border
- PDA: continuous crescendo-decrescendo “machinery” murmur
Right to left shunt and chronic hypoxia:
- Cyanosis
- Clubbing
- Dyspnoea
- Plethoric complexion (a red complexion related to polycythaemia)
What is the prognosis with Eisenmenger syndrome?
- Reduces life expectancy by 20 years
- Risks of infection
- Heart failure
- VTE
- Haemorraghe
How is Eisenmenger Syndrome managed?
Should catch defect and surgically correct it before this happens!!
Definitive management: Heart-Lung Transplant
What is coarctation of the aorta and how may it present?
Narrowing of the aortic arch at the ductus arteriosus associated with Turner’s syndrome. Leads to high pressure proximal to the narrowing and low pressure distal to it
- High blood pressure in upper right limb
- Systolic murmur below left scapula and left clavicle
- Weak femoral pulses
- Tachypnoea and increased work of breathing
- Poor feeding
- Grey and floppy baby
Additional signs may develop over time:
- Left ventricular heave due to left ventricular hypertrophy
- Underdeveloped left arm
- Underdevelopment of the legs
How is coarctation of the aorta managed?
- May just monitor
- In cases of critical coarctation where there is a risk of heart failure and death shortly after birth Prostaglandin E is used keep the ductus arteriosus open while waiting for surgery. This allows some blood flow flow through the ductus arteriosus into the systemic circulation distal to the coarctation. Surgery is then performed to correct the coarctation and to ligate the ductus arteriosus.
What is Tetralogy of Fallot?
- VSD
- Overriding aorta
- Pulmonary valve stenosis
- Right ventricular hypertrophy
RESULTS IN A RIGHT TO LEFT SHUNT SO CYANOTIC
What are some risk factors for Tetralogy of Fallot?
- Rubella infection
- Increased age of the mother (over 40 years)
- Alcohol consumption in pregnancy
- Diabetic mother
- Family history
- CHARGE syndrome
- DiGeorge syndrome
- VACTERL
What are the different severities of TOF?
Severity depends on how bad PS is
Mild (‘Pink’ TOF)
Usually asymptomatic but by age 1-3 years they will develop cyanosis
Moderate-Severe (Cyanotic TOF)
May present in the first few weeks of life with cyanosis and respiratory distress. These infants may be prone to develop recurrent chest infections or fail to thrive.
Extreme
TOF with pulmonary atresia (10% of TOF patients) or absent pulmonary valves (6%).
These are true ‘duct dependent lesions’ as the only way deoxygenated blood can flow into the lungs is through a patent ductus arteriosus (PDA). These infants are often detected on antenatal scans. However, if undetected in pregnancy they will present within the first few hours of life with marked respiratory distress and cyanosis.
What will you find on examination of a child with TOF?
- Central cyanosis
- Ejection systolic murmur due to pulmonary stenosis (VSD too loud to cause a murmur)
- Right heave or thrill
- Clubbing
What will you find on examination of a child with TOF?
- Central cyanosis
- Ejection systolic murmur due to pulmonary stenosis (VSD too loud to cause a murmur)
- Right heave or thrill
- Clubbing
- Poor feeding and weight gain
- Signs of congestive heart failure: sweating, pallor, tachycardia, hepatosplenomegaly, generalised oedema, bilateral basal crackles
When does TOF tend to present?
- Antenatal scans
- Newborn baby checks
- Signs of heart failure in early infant life
What are some differentials for TOF?
Other cyanotic CHD:
- Critical PS
- Transposition of the Great Arteries (TGA)
- Totally anomalous pulmonary venous drainage (TAPVD)
- Hypoplastic left heart syndrome (HLHS)
Isolated VSD: commonest CHD (15-20%). Does not cause cyanosis as the shunt is left-to-right unless Eisemenger syndrome develops
Sepsis: should be suspected in any infant with respiratory distress and hypoxia.
What is a Tet spell?
Intermittent symptomatic periods where the right to left shunt becomes temporarily worsened, precipitating a cyanotic episode
Precipitated by waking, physical exertion or crying
Symptoms: irritable, cyanotic, short of breath, reduced consciousness, seizures and potentially death.
What is the pathophysiology of a Tet spell?
- Increased pulmonary resistance
- Decreased systemic resistance (e.g exercise, more CO2 so vasodilation)
Blood will take path of least resistance so more blood shunted from right ventricle to aorta so bypasses the lungs
How can Tet spells be managed?
CAN BE LIFE THREATENING!
- Knee to chest position or Squat to increase systemic resistance
- Oxygen
- Beta blockers to relax right ventricle and improve flow to the pulmonary vessels
- IV fluids can increase pre-load
- Morphine can decrease respiratory drive, resulting in more effective breathing
- Sodium bicarbonate can buffer any metabolic acidosis that occurs
- Phenylephrine infusion can increase SVR by vasoconstriction
What investigations should be done if Tetralogy of Fallot is suspected and what will they show?
- ECHO: gold standard
- ECG: may show signs of right axis deviation and RVH
- Microarray: if genetic syndromes suspected (e.g. dysmorphic features)
- CXR: may show ‘boot’ shaped heart (RVH) and reduced pulmonary vascular marking (decrease pulmonary blood flow)
How is Tet of Fallot managed?
Medical
- Manage Tet spells with positioning, fluids, propanolol, morphine
- Prostaglandin infusion at birth to keep DA open to allow flow from aorta to pulmonary arteries
Surgery
- Definitive repair can only be done from 3 months-4years
- 5% mortality as open heart surgery
- Cardiopulmonary bypass via median sternotomy, this involves RVOT stenosis resection, RVOT/pulmonary artery augmentation and VSD patch closure
What surgery can be done for TOF to spare a child time until they are old enough to have definitive surgical repair?
- Transcatheter RVOT stent insertion: this is sometimes done in the neonatal period for infants with severe-extreme TOF to relieve RVOTO. This is done to buy time until the child is bigger whilst providing a patent passage for pulmonary blood flow
- Modified Blalock-Taussig (BT) shunt: This procedure aims to mimic a PDA and increase pulmonary blood flow before definitive repair. It can be done either by anastomosis of the subclavian artery to the pulmonary artery or by creating an artificial shunt using synthetic material (usually GoreTex). The latter is called a modified BT shunt.
What are the complications of TOF?
Untreated
- Polycythaemia
- Cerebral abscess
- Stroke
- Infective endocarditis
- Congestive cardiac failure
- Death (up to 25% in the 1st year of life
Treated
- Pulmonary regurgitation
- Arrhythmias
- Reduced exercise tolerance
- Sudden death
How do patients with TOF need to be followed up?
Lifelong follow up is essential
Regular ECG, echocardiography and in cases of exercise intolerance,cardiopulmonary exercise testing (CPET).
More than 85% children with surgically repaired TOF now survive to adulthood
What is Transposition of the Great Arteries and the pathophysiology of this?
Aorta arises from the right ventricle and Pulmonary Artery arises from left ventricle, leading to two separate systems
Survival depends on shunt (PDA, ASD, VSD)
Due to no rotation of aortopulmonary septum
What are some risk factors for TGA?
Most common cause of cyanosis in the new born!
How may TGA present?
- Often picked up on antenatal scan
- Cyanosis at birth or within a few hours
- PSA/ASD/VSD can support for a few weeks but after this will lead to respiratory distress, tachycardia, poor feeding, poor weight gain and sweating
What investigations can be done to diagnose TGA and what will they show?
- Echocardiogram: shows abnormal position of vessels, gold standard
- CXR: ‘egg on a string’ due to cardiomegaly and narrowed upper mediastinum
How is TGA managed?
Initial management:
- Emergency prostaglandin E1 infusion (alprostadil) to keep the DA patent as a temporary solution that allows mixing of blood
- Emergency atrial balloon septostomy to allow for mixing
Definitive and Long‐term management:
- Arterial switch operation [ASO] via open heart surgery with bypass performed before the age of 4 weeks
- Long term follow up and counselling in the future if female patients wish to get pregnant
What are some complications with TGA?
- Neopulmonary stenosis
- Neoaortic regurgitation
- Neoaortic root dilatation
- Coronary artery disease
- Obstructed coronary arteries
- Sudden cardiac death
- MI
- Neurodevelopmental abnormalities
What are some predictors of poor outcomes with TGA?
- Low gestational age
- High pre-operative lactate
Likely to have neurodevelopmental issues
What is Ebstein’s anomaly?
Low set tricuspid valve so smaller right ventricle so poor flow into pulmonary vessels
Often right to left shunt
Presentation
- Evidence of heart failure (e.g. oedema)
- Gallop rhythm heard on auscultation characterised by the addition of the third and fourth heart sounds
- Cyanosis
- Shortness of breath and tachypnoea
- Poor feeding
- Collapse or cardiac arrest
What is hypoplastic left heart syndrome?
LV is so underdeveloped that it cannot be the source of systemic circulation
Survival depends on a PDA and ASD
What is the cause of congenital aortic stenosis?
- Bicuspid valve
- Turner’s syndrome
- Rheumatic fever
What two cardiac defects is Turner’s syndrome associated with?
- Aortic stenosis
- Coarctation of aorta
How may aortic stenosis in a child present?
- Asymptomatic
- Ejection systolic murmur that radiates to carotids
- Fatigue
- Dizziness and SOB that is worse on exertion
- Ejection click just before the murmur
- Palpable thrill during systole
- Slow rising pulse and narrow pulse pressure
How is aortic stenosis diagnosed and managed in children?
Definitive test: Echocardiogram
Other Ix: ECG, exercise testing
Management: see image
What are some complications of aortic stenosis in children?
- Left ventricular outflow tract obstruction
- Heart failure
- Ventricular arrhythmia
- Bacterial endocarditis
- Sudden death, often on exertion
What conditions is congenital pulmonary stenosis associated with?
- Tetralogy of Fallot
- William syndrome
- Noonan syndrome
- Congenital rubella syndrome
How may pulmonary stenosis present in a child?
- Often asymptomatic and found incidentally by murmur
- If severe may have fatigue on exertion, shortness of breath, dizziness and fainting
How is pulmonary stenosis diagnosed and managed in children?
Diagnosis: Echocardiogram
Mx: If mild just watchful waiting under paediatric cardiologist. If severe can do balloon valvuloplasty through femoral vein to IVC with x-ray guidance. If still fails then open heart surgery
How is paediatric heart failure managed?
- Sit up- right
- Oxygen
- Calories via NG feed
- Diuretics (furosemide 1mg/kg/24hr infusion ± spironolactone)
- Duct dependent cyanotic conditions will need alprostadil (PgE1) to maintain patency
- Transfer to neonatal cardiac centre
Babies cannot describe symptoms so how can we tell they may have paediatric heart failure?
- SOB
- Exercise intolerance
- Growth failure
- Poor feeding
- Tachycardia
- Sweating
What is important about the volume of a murmur?
VSD: Larger the defect, quieter the noise
Outflow obstruction e.g AS: Worse defect, louder the noise
What rhythm suggests congestive cardiac failure?
Gallop rhythm
What are some signs that congenital heart disease has/is decompensating to heart failure?
- Poor feeding
- Dyspnoea
- Failure to thrive
- Tachycardia (bradycardia or inappropriately normal rate suggests imminent arrest)
- Hepatomegaly
- Cool peripheries
- Acidosis on ABG
- Cyanosis (TGA, tetralogy of Fallot, tricuspid or pulmonary atresia)
How is heart failure due to congenital heart disease investigated?
- FBC
- CXR
- PaO2 (air and 100% FiO2)
- ECG
- Echo, ± cardiac catheter/advanced imaging techniques
How is congenital heart failure managed?
- Sit upright
- Oxygen
- Calories via NG feed
- Diuretics (furosemide ± spironolactone)
- Fluid restrict to 130ml/kg/day
- Duct dependent cyanotic conditions will need alprostadil (PgE1)
- Transfer to neonatal cardiac centre
