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The Cardiovascular System

coronary angioplasty (PTCA), which was first performed in 1977. A wire is passed from the femoral
artery in the leg or the radial artery in the arm up to the diseased coronary artery, to beyond the area of
the coronary artery that is being worked upon. Over this wire, a balloon catheter is passed into the
segment that is to be opened up. The end of the catheter contains a small folded balloon. When the
balloon is hydraulically inflated, it compresses the atheromatous plaque and stretches the artery wall to
expand. At the same time, if an expandable wire mesh tube (stent) was on the balloon, then the stent
will be implanted (left behind) to support the new stretched open position of the artery from the inside.

Dilated and Inflamed Veins

Varicose Veins

Varicose veins are veins on the leg which are large, twisted, and ropelike, and can cause pain,
swelling, or itching. They are an extreme form of telangiectasia, or spider veins. Varicose veins result
due to insufficiency of the valves in the communicating veins. These are veins which link the
superficial and deep veins of the lower limb. Normally, blood flows from the superficial to the deep
veins, facilitating return of blood to the heart. However, when the valve becomes defective, blood is
forced into the superficial veins by the action of the muscle pump (which normally aids return of blood
to the heart by compressing the deep veins). People who have varicose veins are more at risk of getting
a Deep Vein Thrombosis (DVT) and pulmonary embolisms.

Phlebitis

Phlebitis is an inflammation of a vein, usually in the legs. This is usually the most serious if found
in a deep vein. However, most people with the condition, perhaps 80 to 90 percent, are women. The
disease may also have a genetic component, as it is known to run in families.

Congenital Heart Defects

Heart defects present at birth are called congenital heart defects. Slightly less than 1% of all
newborn infants have congenital heart disease. Eight defects are more common than all others and
make up 80% of all congenital heart diseases, whereas the remaining 20% consist of many
independently infrequent conditions or combinations of several defects.

Acyanotic Defects

Acyanotic heart defects are those in which there is a normal amount of oxygen in the bloodstream.
The most common congenital heart defect is a ventral septal defect, which occurs in about 20% of all
children with congenital heart disease. In VSD blood from the left ventricle is shunted to the right
ventricle, resulting in oxygenated blood returning into pulmonic circulation. One of the potential
problems of VSD is pulmonary hypertension.

Cyanotic Defects

Cyanotic heart defects refer to defects that result in decreased amounts of oxygen in the blood. In

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