Purpose: A heart valve replacement surgery is required in the following conditions:

1. Stenosis: The narrowing of the blood vessels, leading to a lesser amount of blood flowing to the heart is known as stenosis. The muscles need to work harder in such cases.
2. Regurgitation: Leaky valves cause the valve to remain open slightly, instead of closing tightly. This leads to the backward flow of blood. This condition is known as regurgitation.

Causes: The various causes of heart valvular diseases, which may require a heart valve replacement surgery include:

• Congenital condition (present during birth)
• Increase in age
• Prolapse (floppy flaps of the valves)
• Presence of holes in the flaps
• Endocarditis (valve infection)
• Rheumatic fever (a type of bacterial throat infection)
• Hypertension (high blood pressure)
• Aortic aneurysm (dilation of the aorta, which is the main blood vessel of the heart)
• Tumors
• Use of some types of medications
• Radiation therapy (a form of cancer treatment)
• Chronic or long-term inflammatory conditions

Symptoms: The following symptoms indicate a heart valve disease, which may require a heart valve replacement surgery:

• Shortness of breath
• Weakness
• Lightheadedness
• Dizziness
• Chest pain
• Retention of fluid, especially in the lower limbs

1. Physical examination: The doctor will note down your symptoms and medical history, and evaluate you physically.

2. Blood tests and urine tests: These tests help in checking for any underlying medical condition or infections that may be present. 

3. Imaging tests: Imaging tests like chest x-ray, CT scan, and MRI scan help in obtaining clear images of the heart.

4. Echocardiogram: Sound waves are used for creating images of the heart in motion. This helps the doctor in checking the blood flow through the heart and heart valves.

5. Electrocardiogram (ECG or EKG): This test helps in the measurement of the heart’s electrical activity. It helps diagnose heart problems.

6. Stress test: The symptoms of the patient are noted during some physical activity or by the use of some medications.

7. Cardiac catheterization: A thin tube, called a catheter, is inserted through a blood vessel in the groin or arm region, and then guided to an artery in the heart. A dye is injected by the surgeon through the catheter to make the artery more visible on an x-ray. This helps the doctor to obtain a clear image of the arteries in the heart, and how well the heart functions. It also helps in the measurement of the pressure inside the chambers of the heart.

A heart valve replacement surgery can be done in the following ways:

1. Open heart surgery:

• This procedure is usually performed under general anesthesia (the patient is asleep during the surgery).
• The surgeon makes a six-to-eight-inch opening in the chest region.
• The surgeon will split open the breastbone.
• The heart stops functioning and a heart-lung bypass machine now takes over the function of pumping blood.
• The damaged valve is removed by the surgeon. It is replaced by a mechanical or biological valve.
• The heart is now restarted.
• The chest incision is closed up using sutures (stitches).
• The procedure is completed in two to four hours.

2. Minimally invasive procedure:

• The surgeon makes small incisions (cuts) of about 2 to 4 inches.
• The procedure is done without opening the chest.
• The incisions are normally made in a J-shaped pattern.
• The damaged heart valve is removed and replaced.
• A minimally-invasive surgery causes less trauma, bleeding, and pain compared to open surgery. It also has a quicker recovery.

The complications of a heart valve replacement surgery could include:

• Infection
• Bleeding
• Heart attack
• Stroke (stopping of blood supply to the brain)
• Arrhythmias (the irregular rhythm of the heart)
• Valve dysfunction of the replaced valves
• Lung problems
• Pneumonia
• Death

• The patient is kept in the ICU for a couple of days after the procedure, where the vital parameters of the patient are monitored.
• The patient is then moved to a regular hospital room, once intensive care monitoring is not needed.
• The patient usually goes home three to ten days after the procedure.
• It is normal to have some pain, bleeding, and swelling after the procedure.
• The doctor will prescribe pain-relieving medications to relieve your pain after the surgery.
• Follow-up appointments with your doctor will include check-ups and lab tests like x-rays, echocardiogram, and ECG, to check the healing.
• If the doctor has placed a mechanical valve, you will need to take blood-thinning medications for the rest of your life. 
• The breastbone will take about 6 to 8 weeks to heal.
• Complete recovery may take about 3 months.
• The doctor may suggest mild to moderate exercises to help you recover fast.
• Avoid heavy lifting and strenuous physical activities for some weeks after the procedure.
• If you have a desk job, you can return to work within 6 to 8 weeks of the procedure. In case of a job requiring more physical work, you may only return to work three months after the procedure.