WHAT IS AORTIC VALVE?
Heart has four valves named as Aortic valve,Mitral valve,Tricuspid vale and Pulmonary valve. Aortic valve is the one situated betveen left ventricle and Aorta. Left ventricle is one of the four chambers of the heart and Aorta is the major blood vessel arising from the left ventricle distributing oxygenated blood to entire parts of our body. Function of any valve is to allow flow of blood to only one direction.
WHAT IS AORTA?
Aorta is the major blood vessel arising from the left ventricular side of heart and carries oxygenated blood to entire parts of the body. In an adult it is about 2.5 cm in diameter ,in children it will be correspondingly less. In adult if it increases beyond one and half times of its diameter it is called aortic aneurysm.
WHAT ARE THE DISEASES OF AORTIC VALVE?
As any other valves, aortic valve can be functionally either narrowed or leaky . This narrowing or leaking can be due to a variety of reason starting from, BIRTH DEFECTS, RHEUMATIC AFFLICTIONS, BACTEREAL INFECTIONS, CALCIFIC DEGENERATION OF ADVANCED AGE,TRAUMA ,etc
When the aortic valve is narrowed it is called Aortic stenosis and when it is leaky, it is called Aortic regugitation.
WHAT IS CONGENITAL AORTIC STENOSIS?
Certain unfortunate babies are born with narrowed aortic valve, cause of which canot be assessed clearly and if it is severe ,might really struggle to live. Some of these children can be saved by timely operation while others canot be.
WHAT IS BICUSPID AORTIC VALVE?
Bicuspid aortic valve is a normal anatomic variation of Aortic valve where only two leaflets are present instead of three. Though people born with this condition wont be suffering in in childhood or adult hood ,likely to develop degenerative calcification
WHAT IS CALCIFIC AORTIC STENOSIS?
Usually in middle aged or aged population, especially if they have bicuspid aortic valve,small wear and tears on the aortic valve due to high velocity flow lead to slow calcium deposition and eventually become severe enough to cause narrowing.
WHAT IS RHEUMATIC AORTIC VALVE DISEASE?
Rheumatic fever is an immunological reaction affecting the heart tissues in response to a strptococcal bactereal infection anywhere else in the body like throat. In the acute phase of this disease ,joints get swollen due to arthritis and then myocardial tissues and endocardium get inflamed,sometimes leading to acute failure. More often this pathology lead to a chronic inflamation of valve tissues leading to either a narrowing or leak.
WHAT IS INFECTIVE ENDOCARDITIS?
Many bacterea or fungi or virus get access to the blood stream which either get lodged somewhere and start an infective pathology or get destroyed by the body's immunological system. If the aortic valve is already got afflicted by a rheumatic pathology or congenital pathology or underwent an operation like valve repair or replacement, these organisms are likely to get stuck there more often to start a infective pathology. This process is called infective endocarditis and can lead to either a stenosis or regurgitation.
WHAT IS ANNULO-AORTIC ECTASIA?
In certain pathologies, the collagen tissues which is the basic framework protein of aorta, aortic annulus and leaflets are inherently damaged due to defect in metabolism. This lead to weakening of these tissues and the annulus and aorta tend to enlarge which is called annulo-aortic ectasia. This usually lead to leakage of the aortic valve and sometimes to the ballooning of aorta which is called aortic root enlargement or aortic root aneurysm.
HOW AORTIC STENOSIS AFFECT THE HEART?
Aortic stenosis impedes the forward flow of blood flow from the left ventricle to aorta. The left ventricle being a muscular chamber capable of hypertophy of its muscle wall, LVH or left ventricular hypertophy setsin, which in its later stages impairs its pumping or ejecting function as well as accomodating or diastolic function. This causes a forward pump failure or otherwise a heart failure. Result in reduced blood flow to vital organs, symptoms like weakness,tiredness,easy fatigability,etc
HOW AORTIC REGURGITATION AFFECTS HEART?
Function of any valve is to allow flow to only one direction. Aortic regurgitation ia a leak which means a failure of the valve. The immediate affect on the heart is dilatation of the muscular left ventricle and heart as a whole impeding its effective out flow leading to heart failure. In the later stages heart can be so impaired so that its effective ejection function come down from normal 80% to as low as 20% or less. In late stages pressures inside the let atrium and lungs also can go up.
WHAT ARE THE SYMPTOMS OF AORTIC STENOSIS?
Initially little breathlessnes,suffocation especially after some physical actvities, later get progressed to more severe grades. In the later stages there may be little chest pain also mimicking coronary artery diseases. Elderly with moderate to severe aortic stenosis can go into severe heart failure state when they are affected by co-existing pathologies like pneumonia, viral infections or acute coronary syndromes.
WHAT ARE THE SYMPTOMS OF AORTIC REGURGITATION?
Symptoms may be same as aortic regurgitation but with a lower severety. Heart gets enlaged slowly without much symptoms only to get diagnosed in very stages when the ejection fraction has gone down to as low as 20 percent.
HOW AORTIC DISEASE ARE DIAGNOSED?
A suitable analysis of symptoms and physical examination will point towards an aortic valve disease, but an imaging with Echocardiogram is confirmatory ,sometimes combined with CT scan is confirmatory. If the aortic root is found diseased ,the entire aorta has to be visualised by CT aortogram or conventional angiogram.
WHAT IS AN ECHOCARDIOGRAM?
Echocardiogram is a harmless imaging test much like ultrasonogram in which sound waves are are used to visualise the inside of heart, functions of the heart as well as the conditions of valves.
IS THERE ANY MEDICINES FOR AORTIC VALVE DISEASES?
As such aortic valve being a structural pathology, there is no medicine which will reverse the pathology. Medicines prescribed are usuall to counter the after effects of pathology. Valves with minor patology are prone to get infected, so they have to be covered with antibiotics while any bactereal or fungal infection affect the body, or undergoing any procedures like dental treatment when there is huge possibility of bactereal organisms flooding the circulation. Diuretic medicines which help to pass excess water in the body are used to ameliorate the symptoms of heart failure and angiotensin enzyme blockers like Ramipril are used to prevent deterioration of left ventricular dysfunction.
WHAT ARE THE TREATMENT OPTIONS FOR AORTIC VALVE DISEASES?
Aortic Valve Replacement
WHEN SHOULD ONE LOOK FOR SURGICAL TREATMENT IN AORTIC VALVE DISEASES?
1.If the symptoms have progressed to such a level that daily life comforts are compromised.
2.If the heart size is increasing grossly as per chest xray and echocardiogram
3.If heart function is detereorating
4.If the gradient across the aortic valve is very high.