10 - Cardiology Flashcards
What are some cyanotic and acyanotic 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 heart 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