Ventricular Septal Defect
An abnormality in the septum between the left and right ventricles. This is the commonest congenital heart defect, but VSD’s can also be acquired.
- Congenital: Isolated VSD or part of Tetralogy of Fallot.
- Acquired: Most commonly post MI around 24-72hrs causing sudden haemodynamic collapse.
- Pansystolic murmur with ejection character (heard best between the pulmonary and tricuspid areas.
- Murmur characteristic is dependent on the size of the defect. Larger defects create quieter murmurs as the flow passes easier between the ventricles causing less turbulent flow.
- A very loud pansystolic murmur of a small VSD is also known as the ‘Maladie de roger’.
- Signs of right heart failure (peripheral oedema, raised JVP)
- Eisenmengers syndrome: The left to right shunt that occurs with the VSD eventually causes worsening pulmonary hypertension until eventually the pressure in the right ventricle is greater than that of the left. As such a right to left shunt occurs causing cyanotic heart disease. The main signs are that of an audible murmur, cyanosis and clubbing if the cyanosis is longstanding.
- Raised JVP often occurs. The JVP can be fixed raised with the rare Gerbode effect. This is when the VSD is between the left ventricle and right atrium, not the right ventricle.
Associations: Patent ductus arteriosus (10%), Aortic regurgitation (5%), Endocarditis.
Complications: Asymptomatic in small VSDs but heart failure and endocarditis in large VSDs.
- If congenital 30-50% of these close spontaneously. Surgical closure should e considered if there is a significant left to right shunt or increasing right heart pressure.
- Acquired VSD are normally accompanied by haemodynamic instability and require surgical repair early otherwise there is a poor prognosis.
Atrial Septal Defects
Defect in the septum between the left and right atria. There are 3 main types:
- 15% of cases
- The most inferior defect occurring just above the AV valves and also known as the atrioventricular septation defect.
- Occurs due to abnormal development of the endocardial cushions
- Associated with VSDs
- ECG findings: RBBB with left axis deviation
- commonest type = 70% of cases.
- Due to defect in central fossa ovalis
- ECG findings: RBBB with right axis deviation
Sinus Venosus ASD:
- 15% of cases
- Defect in folding of the atrial wall near the SVC, causes an SVC with communication with both atria.
- Soft ejection systolic murmur loudest at the pulmonary area due to increased flow across the pulmonary valve. So the murmur is similar to that of pulmonary stenosis but not as harsh.
- Fixed splitting of S2 (P2 is delayed due to the increased flow across the pulmonary valve causing the valve to close later)
- Can get functional TR
- Signs of pulmonary HTN (loud P2)
- Signs of right heart failure
Surgical closure is advised if:
- Symptomatic ASD (symptoms of RVF)
- Paradoxical embolism
- Asymptomatic patient with significant shunt
- Significant pulmonary HTN (>2/3 systemic pressure) that improves on vasodilation testing
Patent Ductus Arteriosus
Patent embryological connection between the pulmonary trunk and the descending thoracic aorta which normally closes at birth. Increased risk in premature babies, females, babies born at high altitudes and in neonatal rubella syndrome.
PDAs not noticed in childhood are often found incidentally in adulthood. Large PDA’s often present in childhood with signs of LVF and LA dilatation (AF/ palpitations). If untreated patients with large PDAs can develop Eisenmengers syndrome in childhood. Smaller PDAs often are found incidentally in adulthood but do pose a risk of endarteritis.
- Differential cyanosis and clubbing (in patients with eisenmengers syndrome)*
- Collapsing pulse
- Wide Pulse Pressure
- Displaced thrusting apex in large PDA
- Signs of pulmonary HTN (loud P2, left parasternal heave of RV pressure overload)
- Machinery murmur:
- continuous murmur; starting with crescendo systolic murmur which tapers down to a quieter machinery murmur in diastole.
- disappears if the shunt reverses in Eisenmengers syndrome.
- As pulmonary hypertension develops the pressures between the aorta and pulmonary trunk become more equal so the machinery diastolic component stops as the majority of flow then only occurs in systole.
Surgical closure with percutaneous deployed duct closure device recommended if:
- Any PDA that develops endarteritis should be closed post treatment
- Tiny clinically undetectable ducts don’t require closure.
- All other ducts that are detectable should be closed unless significant unreversible pulmonary HTN has developed.
Coarctation of the Aorta
- Lower body underdeveloped in comparison to upper body
- Signs of surgical repair (left thoracotomy scar, can have raised left as a complication of surgery)
- Look for stigmata of endocarditis
- Radio-radial delay if coarctation proximal to left subclavian
- Radio-femoral delay and volume deficit
- Differing upper limb to lower limb BP (lower BP in femoral artery compared with brachial)
- Signs of co-existing syndromes: Turners
- Normal or loud S1, systolic murmur from coarctation loudest over thoracic spine, begins 1/3 into systole and the length corresponds to severity of coarctation (increasing length of murmur = more severe coarctation) with severe coarctation causing a murmur which continues into diastole.
- Can also get ESM of aortic stenosis from often associated stenosed bicuspid aortic valve.
- Uncontrolled HTN – often with symptoms including epistaxis and headaches
- Endarteritis: Infection of aorta (like endocarditis of aorta), often presenting as PUO.
Cardiac: Bicuspid AV, PDA, VSD, mitral valve disease & aortic dissection
Non-cardiac: Turners syndrome, Berry’s aneurysm, Neurofibromatosis 1, Marfans syndrome.
Surgical: Indicated repair if: symptomatic patient with peak pressure difference of >30mmHg or in asymptomatic patient with hypertension or LVH.
Tetralogy of Fallot
A congenital condition which includes four (hence tetralogy) cardiac defects:
Pulmonary Stenosis/ Right ventricular outflow tract obstruction
Right Ventricular Hypertrophy
Overriding Aorta: The aorta receives outflow from the right and left ventricles.
Often remembered by the anagram PROVERB: Pulmonary Stenosis/ Right ventricular outflow tract obstruction
Right Ventricular Hypertrophy, Overriding Aorta, VSD. The ERB stands for: Exercise induced syncope ( a main symptom), Right sided aortic arch ( a common association in 20%) & Blalock-Taussig shunt (a technique used to palliate patients, which is a direct shunt between the subclavian and ipsilateral pulmonary arteries.
To be an adult patient present in PACES the patient must have had their fallots tetralogy surgical repaired with or without a Blalock-Taussig shunt as a temporary measure. This is because without surgical repair fallots tetralogy has a poor prognosis with only ~5% of patients surviving to 4 years old with no treatment. As such the case involves looking for signs of repair, a previous shunt, complications of surgery and for associated conditions.
of Surgical repair: Sternotomy scar for total repair
of use of a Shunt:
- Left lateral thoracotomy scar,
- Radio-radial pulse deficit with a weaker pulse on the side of the shunt.
- The arm on the shunted side may be slightly underdeveloped.
- Patients can develop regurgitation of any of the four valves with all the accompanied signs.
- Patients can also develop RVOT obstruction due to re-stenosis of a pulmonary valve replacement.
- Permanent pacemaker may be in-situ for post op complete AV block or for refractory ventricular arrhythmias.
of Associated conditions:
- DiGeorge syndrome: abnormal facies (cleft palate/repaired, long face & low set ears)
- Polands Syndrome: Unilateral pectoral hypoplasia
Late complications: Pulmonary regurgitation (if had a transannular patch to repair RVOT), Residual VSD, Arrhythmias (Atrial flutter, ventricular arrhythmias -often from scarred RVOT). AR and aortic root dilatation.
Written by Dr Thomas Craven
Resources used to write this document are listed in the references section of this webpage