Angioplasty

Encyclopedia of Medicine by Jeffrey Peter Larson

Angioplasty is a medical procedure used to widen the opening of a blocked artery by the insertion of a balloon-tipped catheter. Regions of the body treated include blocked arteries in the heart, and limbs or arteries supplying vital organs, such as the kidneys.

Angioplasty is a treatment used to improve the decreased blood flow resulting from blocked arteries, without removing blood vessels from another part of the body (which is often necessary in bypass surgery). Decrease in blood flow to the heart is termed coronary artery disease. Angioplasty is also used in a similar manner in blocked arteries in the limbs, especially the legs, which is the result of peripheral vascular disease. Once inserted into the desired artery, the balloon in the tip of the catheter is inflated to compress open the plaque, thus widening the diameter of the artery. This plaque buildup en route to the heart, the legs, or in arteries to vital organs, is usually the result of the accumulation of fatty deposits (atherosclerosis). The goal of angioplasty is to return adequate blood supply to the regions that are deprived.

Precautions of angioplasty include precautions similar to those taken for any other surgical or invasive medical procedure. Patients undergoing angioplasty may require special precautions if they are obese, smoke, have bleeding tendencies, or are over 60. As with other surgical interventions, precautions are taken for those patients who may have recently experienced an illness such as pneumonia or a heart attack. Patients on medications such as heart and blood pressure medicine, blood thinners, muscle relaxants, tranquilizers, insulin, or sedatives may require special lab tests prior to angioplasty and special monitoring during the procedure.

Coronary angioplasty is performed by a physician specializing in disorders of the heart (cardiologist). The procedure consists of the insertion of a balloon catheter into the blocked artery. This catheter is a very thin tube and is pushed through the inside of the blood vessel, bringing the tip of the catheter to the location of the blockage in the artery, which has been evaluated by angiography. At this point in the procedure, the balloon at the tip of the catheter is inflated, stretching the artery narrowed by the plaque. Sometimes a metallic stent is placed to help keep the artery open. The physician then removes the catheter and balloon, thus allowing blood to flow normally again.

Angioplasty of blocked arteries in the extremities or supplying organs, such as the kidneys is performed by a physician specializing in interventional radiologic procedures. The procedure is similar to coronary angioplasty.

The individual undergoing an angioplasty enters the hospital the morning of procedure. Instructions are given not to eat or drink anything after midnight on the night before the procedure. However, under some circumstances a clear liquid breakfast is allowed. Blood tests, an electrocardiogram (ECG), and a chest x ray may be performed prior to procedure. The patient is also instructed that emergency surgery may be necessary in the event of complications arising during the angioplasty.

The area where the catheter is inserted (arm or groin) is shaved and prepared with antibacterial soap to prevent infection. Electrode patches are placed on the individual's chest to monitor heart pattern, rate, and rhythm during the procedure. A local anesthetic is injected into the site where the catheter is inserted. As the x-ray dye is injected into the blood stream, the patient may feel a warm flush feeling. Medications may be given intravenously to decrease the patient's anxiety during the procedure.

After angioplasty, an observation period is required in a cardiac care unit or a hospital room for several hours up to two days. This recuperation period depends on the location of the blockage and the patient's overall medical condition. If the angioplasty catheter is inserted into the femoral artery in the groin, the individual is instructed to lie flat and keep the affected leg straight for at least six hours. The arm or groin puncture site is closely observed for bleeding or hematoma, and peripheral pulses of the affected extremity are frequently checked. A pressure dressing may be applied to the puncture site to prevent excess bleeding. A cardiac monitor is used to monitor the patient's heart pattern, rate, and rhythm after coronary angioplasty. Once the patient's condition is satisfactory, the individual is allowed to return home.

Individuals undergoing angioplasty have a remote risk of an allergic reaction to the local anesthetic or the x-ray dye, which can also be harmful to the kidneys. There is also a risk of excessive bleeding at the site of the catheter entry that may require additional medical attention. If there is damage to the artery, such as perforation during the procedure, an emergency situation could arise resulting in bypass surgery or surgery to repair of the perforation. Because of the nature of the procedure and cardiac involvement in coronary angioplasty, there is a risk of a disturbance of the heart's rhythm or, rarely, a heart attack or stroke.