Stenosis

Unusual narrowing of the blood vessels or other tubular structures or organs is referred to as stenosis. In simple words stenosis means narrowing of the various body parts. The common causes for stenosis include birth defects, inflammation, neoplasm (abnormal proliferation of cells), ischemia (reduction of blood supply thus damaging tissues), infection, iatrogenic (complications arising from any treatment) and atherosclerosis.

Spinal stenosis: Specific causes include rheumatoid arthritis, osteoarthritis, aging, spinal injury or tumor and spondylosis. Symptoms include pain and weakness in the legs along with cramps, imbalance and loss of control over bladder and bowel movements.

Mitral valve stenosis: Specific causes include endocarditis, atrial myoxma, rheumatic fever and Lutembacher syndrome. Symptoms of mitral valve stenosis are fatigue, recurrent respiratory infections and swelling in the feet.

Aortic valve stenosis: This type of Stenosis may be caused by rheumatic fever, Williams syndrome, LDL receptor deficiency and senile or bicuspid aortic valves. The typical symptoms of aortic valve stenosis are chest pain and heart murmur, fatigue and shortness of breath and heart palpitations.

Pulmonary valve stenosis: Specific causes include deformity during fetal development, rheumatic fever and endocarditis. This type of stenosis has symptoms of cough and fatigue, fluid retention and shortness of breath.

Treatment differs according to the type of stenosis. While physical therapy, drugs like analgesics and lumbar brace are used to manage spinal stenosis, aortic valve stenosis and pulmonary valve stenosis are treated with valve replacement surgery.

Aortic Stenosis

Aortic Stenosis is a condition where the aortic valve of the heart becomes narrowed. This leads to obstructed blood flow to the aorta from the left ventricle. Aortic Stenosis is more common among men. Elderly persons are likely to face this heart valve disease. When the narrowing of the aortic valve is to a small extent, the patient does not feel any discomfort or other symptoms. But when there is significant reduction in the valve area, it leads to decrease in cardiac output and may result in heart failure. Aortic valve stenosis must not be ignored as it systematically weakens the heart. It forces the left ventricle to work harder.

Aortic Stenosis is often caused by rheumatic fever, calcification of the valve, coronary artery disease or heart murmur. Symptoms of aortic stenosis include chest pain (angina), shortness of breath and fainting spells. They occur due to the heart muscle's inability to cope up with the extreme pressure load laid by Aortic stenosis. Patients suffering from aortic stenosis are likely to feel palpitations, dizziness and chest pain on exertion.

Enlargement of the left ventricle or Aortic stenosis can be diagnosed with the aid of Doppler ultrasound, echocardiogram, chest x-ray and trans esophageal echocardiogram. The physician will be able to notice arrhythmia and enlargement of left ventricle. Diuretics are prescribed to reduce high lung pressure. Blood thinners are used to prevent blood clots from being formed on the surface of the heart valves. Replacement of aortic valves is done in severe cases of valvular failure. Balloon valvuloplasty is a surgical procedure similar to balloon Angiography where a balloon is placed in an artery and later inflated to relieve obstruction.

Restenosis

Restenosis refers to the re-narrowing of the coronary artery after an Angioplasty procedure. It literally means reoccurrence of the stenosis (narrowing of the blood vessel). Restenosis occurs within 3-6 moths in 40-50% of people who have undergone an Angioplasty.

During the procedure of angioplasty a balloon is inserted into the blocked artery and inflated so as to allow the blood to flow normally to all portions of the heart. During this procedure the surrounding tissues undergo trauma and become susceptible for damage. Restenosis may set in during thrombosis or due to fresh tissue growth at the site of the surgery. Restenosis does not indicate progression of the heart disease but may be an indication that the body's immune system is responding to the injury caused during angioplasty.

Modern medicine has seen the use of stents to keep the artery open. Usage of stents has brought down restenosis considerably. Usage of drug-eluting stent allows slow seepage of medication that reduces proliferation of cells thus reducing re-clogging.

Restenosis causes and treatment

Restenosis is mainly caused due to a surgery that unblocks or widens a blood vessel. Treatment depends on the clinical condition:

• If the original surgery had no stent, then a repeat surgery is performed and a stent is fixed.
  
• In case restenosis occurs even after stent has been placed during the first surgery then a repeat angioplasty is done.
  
• Many a times a second stent may also be placed.
  
• Bypass surgery wherein the affected portion of the artery is replaced with another artery from the patient's thigh.
  
• Brachytherapy; wherein radiation is used to remove the scar tissues from inside the artery.