Ventricular septal defect Flashcards
What is VSD?
A congenital heart defect characterized by an abnormal opening in the ventricular septum that separates the L / R ventricles
What shunt occurs in VSD?
Left-to-Right shunt
VSD pathophysiology
- L-R shunt: LV pressure higher than RV –> increased blood flow into RV –> PA
- Vol. overload: RV dilatation and increased pressure –> pulmonary overcirculation –> pulmonary HTN
- Pulmonary HTN –> Eisenmenger syndrome
VSD cyanotic or acyanotic
Acyanotic congenital heart defect
Why is VSD acyanotic?
L to R shunt: blood is still being pumped through the pulmonary valve into the lungs for oxygenation
what is Eisenmenger syndrome
when the left-to-right shunt eventually reverses to a right-to-left shunt due to pulmonary HTN, leading to cyanosis (deoxygenated blood enters systemic circulation) and other complications associated with chronic hypoxia
What murmurs are in VSD
Pan-systolic murmur (occurs throughout the entire duration of systole) at the left lower sternal border (due to turbulent flow from the left to the right ventricle)
VSD risk factors
- FMHx of congenital heart disease
- Down’s syndrome (trisomy 21)
VSD key diagnostic factors
- Presence of risk factors
- Faltering growth
- SOB
- Systolic murmur left parasternal region
small VSD CXR findings
chest x-ray may be normal
Significant VSD CXR findings
- cardiomegaly and increased vascular markings
Eisenmenger’s syndrome CXR findings
prominent pulmonary conus with peripheral pruning of the pulmonary vascular markings
VSD Dx Ix
Transthoracic echo
VSD clinical presentations
Poor feeding
Dyspnoea
Tachypnoea
Failure to thrive
Palpation findings on VSD
Palpable systolic thrill left sternal border
How does VSD increase the risk of infective endocarditis?
Arise from the turbulent blood flow, endothelial damage, and the formation of thrombi, which provide a site for bacterial colonization
Small/Asymptomatic VSD Mx
- Observation: may close on its own
- Monitoring: Regular echo to monitor the size of the defect, the function of the heart, and the presence of any change
- Follow up Assess for signs of HF, failure to thrive or pulmonary HTN
Medical
Symptomatic VSD Medical Mx
- Diurectics: fluid overload / Sx of HX
- ACE-i: reduce the afterload
- Beta-blocker: control HR + reduce workload
- Abx prophylaxis: To prevent infective endocarditis
How to identify the VSD is small on auscultation?
a loud pan-systolic murmur
smaller the defect = louder murmur
Eisenmenger syndrome presentations
- Cyanosis: R-L shunt –> deoxygenated blood entering systemic circulation
- Dyspnoea
- Fatigue
- CP
- Syncope
Large VSD Mx
- Percutaneous transvenous catheter closure (via the femoral vein)
- Open-heart surgery
