Ventricular septal defects (VSD) are congenital abnormalities characterized by a structural deficiency of the ventricular septum that separates lower chambers of the heart.
Due to the presence of a hole in the ventricular septum, blood from the left ventricle mixes with that in the right ventricle which increases the pressure and eventually weakens the pumping ability of the heart.
Types of VSD – Atrioventricular canal type, Muscular, Membranous, Conoventricular, Canal septal or right ventricular outlet.
80 % of VSD type is membranous type.
Small ventricular defects have no major problems and close by itself. Whereas, medium or large defects require surgery to prevent complications.
What are the symptoms of ventricular septal defect?
If the ventricular defect is small, symptoms may not appear until later stages of childhood. Whereas, for the greater defects following symptoms will be presented.
Rapid breathing or breathless
Decreased appetite – failure to thrive
Rapid or irregular heartbeat
What are the causes of ventricular septal defect?
Congenital heart diseases are due to problem in heart development
What are the risk factors of ventricular septal defect?
A genetic problem such as Down’s syndrome
What are the complications of ventricular septal defect?
Heart failure: This condition will develop in case of medium to large VSD because the heart needs to work harder to pump enough blood to the body.
Pulmonary hypertension: increased blood flow to the lungs due to VSD.
Other heart problems such as rhythm abnormalities, and valve problems
How are ventricular septal defects diagnosed?
Echocardiogram – identifies anatomy of the defect and shut size.
Cardiac catheterization: Examines the heart structures, blood pressure and blood oxygen levels in its chambers.
Why should we close VSD?
Most VSD may be closed in childhood
Large non-restrictive VSD present in infancy– need early surgery
Smaller restrictive defects can remain relatively asymptomatic but can result in long-term sequelae such as pulmonary hypertension, left heart dilation, arrhythmia, aortic regurgitation, double chamber right ventricle, or endocarditis
VSD persist beyond age 8 years – does not close
Hemodynamically insignificant VSDs can lead to the risk of developing endocarditis.
Which patients need closure?
Cardiomegaly or left heart dilation by echocardiogram
Qp: Qs greater than 1.5
Failure to thrive
Worsening New York Heart Association class symptoms
Recurrent respiratory infections
History of infective endocarditis
What are the contraindications of device closure?
Irreversible pulmonary vascular disease
Patients with antiplatelet therapy
Active infection or sepsis
Inadequate rim (<2mm) below the aortic valve in a membranous VSD
Aortic valve cusp prolapse
Why device closure and not surgery?
Avoids open heart, on bypass pump surgery
Short hospital stay (< 3 days)
Pain and delayed recovery with surgery
Cosmetic and stigma consequences of surgery
How is VSD treated?
Initially, the child is given anaesthesia for sedation.
Small incision or cut is made in the groin area and catheter will be inserted and directed towards the ventricular septum between the lower chambers of the heart.
Then, a device to occlude the defect is guided with catheter towards defect.
Amplatzer ventricular septal occluder is used in ventricular septal defect closure :
These are self-expandable, double-disc device
This is made from nitinol wire mesh
This can be ruptured and redeveloped for precision in placement
This device provides complete closure of the defect
Once the device is in the right position, it is deployed between the two discs to occlude the defect and catheter will be removed.
Vitals such as Blood pressure, heart rate, temperature, respiration rate, blood oxygen level will be monitored.
Blood tests, Chest X-ray and Electrocardiogram(ECG), Echocardiogram will be done
Infections and bleeding manifestations are checked at the insertion site
How to prevent VSD?
In most cases, you cannot prevent congenital abnormalities. However, the following precautions are taken.
Early prenatal checkup
Avoid alcohol, tobacco, and illegal drugs
Control sugar levels
What is the uniqueness of VSD closure by Dr C Raghu?
Dr Raghu team has performed date 100 VSD device closure procedure. One of the early adaptors to perform VSD device closure in India, Dr C Raghu, has organized the first-ever workshop on VSD device closure in 2011.