Function of a heart valve
Valves enables the smooth blood flow of heart and prevent the retrograde flow (backward flow) of blood. Valves have flaps to close and open the valves. Tricuspid and bicuspid valve opens the blood from right and left atrium to right and left ventricles. When ventricles are filled with blood tricuspid and bicuspid valve closes to prevent the back flow of blood into atrium. when the ventricles are filled with blood pulmonary valves open the blood flow to lungs and aortic valve open blood flow to other parts of body. After emptying ventricle aortic valve and pulmonary valve closes to prevent the back flow of blood into ventricles.
HEART VALVE DISORDERS
The important problem in all kinds of heart valve disorders is that since the valves are unable to open properly there is insufficient blood flow through the valve.
- Valvular stenosis: When tissue flaps that open and close the valve become thick are stiff, valve cannot able to open completely. Resulting reduced blood flow through valve. All the four valves can be affected (Mitral stenosis, aortic stenosis, tricuspid stenosis, pulmonary stenosis)
- Valvular regurgitation: Valve cannot able to close completely causing black flow of blood. Also known as leaky valve or Valvular insufficiency. Heart must work hard to compensate for leaky valve. All the four valves can be affected. (Mitral regurgitation, pulmonary regurgitation, aortic regurgitation, tricuspid regurgitation)
- Valve atresia: Atresia commonly refers to absence or missing of structure. Valve atresia, lack of valve opening for blood to flow through.
Causes of Valvular disorders
- Congenital heart disease: The Person is born with a defective aorta. Instead of three tissue flaps patient will have only two flaps. The person might have defective valve in terms of shape, size and inability to function. Valves may be leaky or narrow down depending on the defect.
- Mitral valve prolapse: Mitral valve doesn’t close properly during heart functioning which causes reverse blood flow into left atrium.
- Rheumatic fever: It is an inflammatory disease caused by improperly treated strep throat. If left untreated causes permanent damage to heart valves. Commonly affects children.
- Endocarditis: Endocarditis is the swelling of inner lining of the heart chambers and valves. Caused by bacteria most commonly by streptococcus and staphylococcus.
Symptoms of heart valve disease
- Shortness of breath
- Chest pain
- Fainting episodes
- Swelling of feet, ankles and abdomen
Critical Objectives in managing a heart valve disease
- Preventing further damage of heart valve
- Improve the blood supply to the body
- Help the patient to cope up with their daily routine
- Repairing or complete replacement of damaged valve
Management of a patient with heart valve disease
- Antiarrhythmic medications
- Anticoagulants (Blood thinner’s)
- Anti-hypertensive drugs
Catheter (thin tube) with small deflated balloon is passed into the blood vessel and guided to stenosed valve and the balloon is inflated. Narrowed valve opens completely and allows more blood to flow through it.
Surgical procedure is done to open the narrow valves to improve the blood flow. The surgeon takes away calcium deposits and other scar tissue from the flaps.
If the calcium deposits prevent flap from closing properly, surgeon will remove calcium deposit to allow the leaflets to function normally.
If leaflet lost its shape or become floppy, part of it is cut and shaped to fit the valve correctly. So that the valve closes completely.
Surgical procedure to repair the prolapsed anterior leaflet of mitral valve. Normal chordae with a leaflet are moved from posterior leaflet to your anterior leaflet. The posterior leaflet is repaired and reshaped.
Annulus, the tissue that supports the valve open. Annulus may weaken due to age, or disease may lose its shape. To reshape annulus ring or band shaped Structure is sewn around it.
If valve leaflet has a hole or tear, it is repaired with tissue patches
Valve replacement surgery
During the surgery, the damaged valve is removed and replaced with mechanical valve or biological valve.
Ross Procedure for heart valve replacement
Surgeon removes diseased aortic valve and replaces it with your pulmonary valve. Pulmonary valve is replaced with a pulmonary valve from a donated human heart preserved in a sterile condition.
Heart Valve Replacement Surgery
Indications: When the valve damage is severe and it can’t be repaired, then total valve replacement is indicated.
Types of heart valves available for replacement surgery
- Mechanical valve: Mechanical valves are made of carbon and polyester that human body accepts well. Advantage of mechanical valves is that it lasts for many years. Only disadvantage is that the patient has to take anticoagulant medicines for rest of their life to prevent formation of blood clots.
- Biological valve: Biological valves are made of donated human heart or harvested from an animal (pig or cow). These valves degenerates over a period of time. The advantage of biological valve is the patients don’t need to take Anticoagulants.
SURGICAL PROCEDURE FOR HEART VALVE REPLACEMENT
Prior to surgery the doctor will perform a complete physical examination, Dental examination, blood test and other investigations to make sure the patient is medically fit for surgery. Just Minutes before the surgery general anesthesia is administered to the patient by anesthetist and the patient’s vitals are monitored continuously by the anesthetist till the surgery is complete.
Frequently surgeons prefer open heart surgery, in which heart is stopped during the procedure and heart-lung machine connected to the patient. Heart lung machine takeover breathing and blood circulation.
Incision is made on the Centre of chest (sternum) vertically and retracted. Sternum is cut and divided to expose the heart. Heart-lung machine is connected to aorta to pump the oxygenated blood to the whole body and receives deoxygenated blood through veins. Now the heart is stopped temporarily. Diseased valve is removed and replaced with mechanical valve or biological valve.
After surgery patient is transferred to intensive care unit to prevent infection and to monitor the vitals. Usually patient and remain in the hospital for five to seven days. Medical staff will offer pain medication as needed and continuously monitor your blood pressure, breathing, and heart function during the first few days after a heart valve replacement. Complete recovery may take six to eight months.
Patients can live a regular long life after valve replacement surgery. Life expectancy of around 20 years is expected among 60 years age groups undergoing surgery.