WHAT ARE CONGENITAL HEART DISEASES ?
Congenital heart diseases a variety of birth conditions of heart starting from simple holes to very complex situatios which make the life imposible. Broadly congenital heart diseases are grouped in to two, cyanotic heart diseases and non-cyanotic heart diseases. Cyanotic heart diseases will have blue color of the skin, tongue and lips and is due to decreased level of oxygen in the blood.
WHAT ARE THE CAUSES OF CONGENITAL HEART DISEASES?
It is very difficult to pinpoint the exact reason of a congenital defect. What we know is that a variation happened in the embryonic formative phase of heart development. Various drugs,radiation,consanguinity,smoking,etc are supposed to cause these defects.
WHAT ARE THE COMMON CYANOTIC DISEASES?
WHAT ARE COMMON ACYANOTIC DISEASES?
WHAT ARE THE SYMPTOMS OF CONGENITAL HEART DISEASES?
Cyanotic heart diseases will have blue colour from birth or early child-hood either at rest or on activity accoding to severity. Cynosis means blue colour and is because of decreased oxygen in the blood. The cyanosis will increase on excercise and sometimes they can have life-threatening cynotic spells. They also feel breathless or tired even on slightest physical activity.
The non-cyanotic disease will have effort intolerace and frequent respiratory infections because of increased blood flow through the lungs.
HOW CONGENITAL HEART DISEASES ARE DIAGNOSED?
Usually symptoms like breathlessness,effort intolerance,blue color,failure of growth,etc from childhood point towards the possibility of a congenital disease. The physical examination, changes in nature of heart sounds,presence of some abnormal sounds and their position with reference to heart,all point to some some congenital heart condition which are many. However the diagnosis is mostly established by an echocardiographic analysis where the abnormality can be accurately imaged. Sometimes if still difficulty is encountering , cardiac catheterisation , CT pulmonary angiogram or cardiac MRI can be utilised.
WHAT IS ASD?
Atrial septal disease is the full form of ASD, and is one of the common congenital heart diseases. The pathology of this condition is that across the hole in the inter-atrial septum, blood gets shunted from left atrium to right atrium because pressures are high in the left atrium. This excess flow across the inter-atrial septum result in doubled flow to the pulmonary circulation,cause pathological changes in the internal lining of vessels leading to what is known as pulmonary artery diseases and pulmonary artereal hypertention. If the pulmonary artereal hypertention increases too much actually a shunt reversal happens which result the victim becoming blue. This particular situation is Eisenmenger syndrome.
WHEN AND WHY SHOULD AN ASD SHOULD BE CLOSED?
Any ASD with a shunt ratio of more than 1.2 is better to be closed best in the pre-school days before their pulmonary circulation becoming hypertensive.
ASD Atrial Septal Defect
WHAT ARE THE COMPLICATION IF ASD IS UNTREATED?
WHAT ARE THE TREATMENT OPTIONS FOR ASD?
Device closure of ASD, surgical closre of ASD either through full sternotomy or through keyhole on the side of chest.
WHAT IS DEVICE CLOSURE OF ASD?
Nearly 60% of ASDs can now be closed by witout cutting the body at all, by introducing a cath-lab guided device of many shapes which will fit in there and completely preventing the shunt across. This procedure can now be accomplished with minimum complications.
WHAT IS VSD(VENTRICULAR SEPTAL DEFECT)?
VSD or ventricular septal defect is a congenital or acquired defect in the anatomic division between right and left ventricles. Since the pressure inside the left ventricle is much higher,blood gets shunted from left to right. This shunting considerably increase the blood flow to the lungs much like the ASD, but with much severity. Depending on the quantity of shunting, pulmonary artery disease and pulmonary artereal hypertention develop and may go into reversal of shunting when it is called Eisenmenger syndrome.
Many VSDs if they are not large enough to cause problems in the childhood may close by itself eventually. However some may remain as such and continue to shunt blood eventually leading to pulmonary artery disease and pulmonary artereal hypertention.
VSD Ventricular Septal Defect
WHAT IS PULMONARY ARTEREAL HYPERTENTION?
The blood pressure inside the systemic circulation and pulmonary circulation are very different.While it is aroud 120/80 in the systemic circulation, it is around 25-30 in the pulmonary circulation in the systolic phase and around 12 to 15 in the diastolic phase. Primary pulmonary hypertention is a situation where the pressure inside the lungs is elevated without any particular cause.
In the case of left to right shunt like cardiac conditions (ASD,VSD AND PDA), the pressure inside the lungs is increased due to pumonary artery disease.
WHAT ARE THE TYPES OF VSDs?
HOW VSDs ARE DIAGNOSED?
If the VSDs are too big at birth,it can cause difficulty in thriving,unable to suck milk,failure to gain weight necessitating urgent surgery. They can have very high pulmonary aretery pressure. On physical examination an abnormal sound called murmur often detected by physician give the suspicion of VSD, which later can be confirmed by Echocardiogram.
Sometimes catheterisation become necessary to assess the severity of pulmonary pressure to decide the operability.
WHEN SHOULD A VSD BE CLOSED?
If the VSD is large enough to cause failure to thrive in the young age, it might have to be closed at the earliest. However if it is less of a problem and small in size, and causing no problem,should be waited periodically walching for increase in pulmonary hypertention and development of complications like leaflet prolapse of aortic leaflets causing aortic regurgitation or development of infective endocarditis.
Any VSDs remainig beyond the age of eight years is unlikely to close and better be closed even if it is small for the fear of infective endocarditis.
WHAT ARE TREATMENT OPTIONS FOR VSD?
WHAT IS TETROLOGY OF FALLOT ?
Tetrology of Fallot is a cyanotic congenital heart disease characterised by blue color either from the birth or few months or years from birth. There are four components for this disease,a ventricular sept,pulmonary stenosis, over-riding of aorta and deviation of outlet septum.This disease is charecterised by blue color of skin,lips and toungue due to lower
content of oxygen in the blood. Blue color can occur either from birth or first few months of birth. As there is hindrance to the flow of blood from right ventricle because of pulmonary stenosis, blood get diverted from right ventricle to left ventricle,thereby bypassing the lungs and hence lower level of oxygenation.
WHAT ARE THE COMPLICATIONS OF TETROLOGY OF FALLOT?
WHAT ARE THE SURGICAL OPTIONS FOR TETROLOGY OF FALLOT ?
WHAT IS TRANSPOSITION OF GREAT VESSELS ?
This is a serious birth anomaly of the heart where Aorta arise from right ventricle instead of left ventricle and Pulmonary artery and pulmonary artery arises from the left ventricle instead of right ventricle. So in effect, instead of the blood circulation being serial,it is actually parallel so that oxygenated blood get circulated again and again in pulmonary circulation and deoxygenated blood get circulated in systemic circulation. Life is possible only if a connection is existing between these circulations in the form of ASD,VSD or PDA.
Depending upon the mixing allowed children can present with failure to thrive ,cyanosis or breathlessness immediately after birth or sometimes after the birth
WHAT IS THE TREATMENT FOR TRANSPOSITION OF GREAT VESSELS ?
At birth both ventricles have equal thickness and within next few weeks,the ventricle which supports pulmonary circulation regresses in muscle thickess because the pressures inside the pulmonary circulation is only a thrid of systemic circulation.
The anatomic correction in Transposition of great vessels is achieved by surgically correcting the great vessels to the normal position where they are supposed to be. This operation is called ARTEREAL SWITCH OPERATION.
WTHAT IS SINGLE VENTRICLE ?
Some babies are born with single ventricle instead of one. There will be a lot of associated anomalies as well. One ventricle will remain rudimentary in this situation. They can be made to live by applying the principe of reptiles living with only one ventricle. The surgical procedure used to rescue these babies are called Fontan operation ,the principle of which is that no ventricle is needed to spport the low pressure pulmonary circulation like in reptiles.
WHAT IS TRICUSPID ATRESIA?
Tricuspid valve is the valve between the right atrium and right ventricle. In Tricuspid Atresia, the Tricuspid valve is not formed ,so the deoxygenated blood reaching the right atrium gets shunted to left atrium and gets mixed with the well oxygenated blood. Patient can have cyanosis and limitation of activities. This condition also get corrected by applying the principle of reptilian heart.