Ventricular Septal defect
Q: What is a VSD?
Ans: VSD is a abbreviation for the Ventricular Septal Defect. This is a hole in the thick interventricular septum, a muscular wall dividing right and left sided pumping chambers.
Q: What is the role of interventricular septum?
Ans: Inter-ventricular septum allows the two pumping chamber to pump at the drastically different pressures.
The heart is a four chamber structure. The upper two chambers are collecting chambers, known as atria. The right atrium collects oxygen deficient blood from the body and the left atrium collects oxygen rich blood from the lungs. Lower two thick muscular chambers are pumping chambers and known as ventricles. The right sided chamber is connected to lung artery and pumps impure or dark red blood to the lungs. This blood gets oxygen during the process of breathing and becomes bright red in colour. It reaches to left atrium and then to left ventricle. Left ventricle then pumps it out to the aorta. Aorta and its branches then carry this oxygen rich blood all over the body. Left ventricle has to work at 4-5 times higher pressure than the right ventricle.
Qns: Why a VSD is harmful to the baby?
Ans: A large VSD allows escape of blood into right ventricle and eventually to the lungs. Normally lungs and body accommodate almost equal amount of blood during each cardiac cycle.
Lungs get extra blood and body gets less than required amount of blood and baby suffers due to this imbalance.
The wet lungs are vulnerable for lung infections. Baby may get about the one episode of pneumonia in every one to two months, they can be life threatening. They also affect the growth of the baby which is maximum in the first 6 months of life.
Qns: We have seen babies who become alright with drugs , then why my doctor advised operation?
Ans: One must remember following points regarding the VSDs:
- Every VSD has a natural history. All VSDs can not close spontaneously.
- The location of VSD is very important in predicting their eventual outcome. A muscular VSD has the probability of spontaneous closure around 80% while a VSD in perimembranous area has 30-40 chance of closure. Even a smaller doubly committed VSD has to be closed as it can harm the aortic valve.
- No medical management can lead to closure of VSD. Moreover, Medical management is done to support the system till VSD is closing either spontaneously or by interventions.
- A VSD is a totally curable disease if intervention is done at the right time, with negligible residual effect.
- A close follow-up and right monitoring with pediatrician, pediatric cardiologist is required.
- One must not disobey the advice. Because once the flooded lung vessels are thickened , they can not reverse to normal even after the successful operation..
Qns: What are the optimum timing for VSD closure?
Ans: A VSD is significant if baby is not growing well , not gaining weight, having perspiration, not able to suck on breast and having high rate of respiration and heart beats and an enlarged heart on X-ray chest.
This baby if not improving on medical management must be operated around 3 months.
If there are features of decrease in lung pressure one can further wait. A murmur getting louder may be a good sign. But a loud murmur can also be due to some complication which your pediatric cardiologist only can tell you.
Qns: Can umbrella device can be used for VSD closures?
Ans: VSDs in muscular region are usually closed by devices. However A significant VSD needs to be closed between 3-6 months. So at this as entry through thigh vessel is difficult. Hence still surgical closure is the treatment of choice for the VSDs
Some times cardiac bypass can be avoided and VSD can be closed by a device by entering into a beating heart by right ventricular anterior wall. This hybrid procedure is done in operation theaters by pediatric cardiologists and pediatric cardiac surgeon. This shortens the hospital stay for the patients.
Qns: My doctor says that a small hole need not to be treated and only SBE prophylaxis to be done. What is the SBE prophylaxis?
Ans: A small hole which is not causing enlargement of heart or other symptoms is not a botheration as it can not affect the lungs.
SBE prophylaxis is not a kind of medication but it is the set of advices given to the patient. In the presence of hole in heart, the smoothness of inner surface of heart is not maintained . The rough area inside the heart can provide a hiding space for bacteria inside the heart. This is a very serious complication for an otherwise benign condition.
A simple way of getting bacteria in the blood is to keep a bad oro-dental hygiene . When we brush our teeth there may be bleeding and also the entrance of bacteria of oral cavity into the blood.
Following are the common precautions to be taken:
i) Brushing of teeth at morning and before going into bed.
ii) Use of mouth-wash particularly after eating candies.
iii) No regular antibiotics are recommended.
iv) Any procedure which can lead to entry of bacteria in blood stream must be precede by appropriate antibiotic administration.
v) No antibiotics must be consumed on self prescription.
vi) Antibiotics preferably must be given after the sepsis screening and blood cultures are done.
vii) Any fever persisting beyond 3-5 days without any obvious cause must be investigated with 3 blood cultures and echocardiography.
Compiled By Dr. Smita Mishra
Senior Consultant, Deptt. of PediatricCardiology
Escorts Heart Institute, New Delhi.
The commonest holes are VSD (Ventricular Septal defect), ASD (Atrial Septal Defect) and PDA (Patent Ductus Arteriosus). VSD is a hole in the interventricular septum or wall between two lower chambers (RV and LV). ASD is the name of the hole in interatrial septum and PDA is actually an extra pipe connecting Aorta and Pulmonary Artery.
Of these three, VSDs are the commonest lesion about 25-30% of all congenital heart defects whereas ASD and PDA are about 5-8% of them. Another point to remember is that all of us are born with small ASD and small PDA. However, VSD is never found in normal heart.