Angioplasty

Angioplasty
Balloon angioplasty.
ICD-9-CM	00.6, 36.0 39.50
MeSH	D017130

Angioplasty is the technique of mechanically widening a narrowed or obstructed blood vessel, the latter typically being a result of atherosclerosis. An empty and collapsed balloon on a guide wire, known as a balloon catheter, is passed into the narrowed locations and then inflated to a fixed size using water pressures some 75 to 500 times normal blood pressure (6 to 20 atmospheres). The balloon crushes the fatty deposits, opening up the blood vessel for improved flow, and the balloon is then deflated and withdrawn.

The word is composed of the medical combining forms of the Greek words αγγειος angeus meaning "vessel" and πλαστός plastus meaning "formed" or "moulded." Angioplasty has come to include all manner of vascular interventions that are typically performed in a minimally invasive or percutaneous method.

History

Diagram of a balloon catheter.

Angioplasty was initially described by the US interventional radiologist Charles Dotter in 1964. Dr. Dotter pioneered modern medicine with the invention of angioplasty and the catheter-delivered stent, which were first used to treat peripheral arterial disease. On January 16, 1964, Dotter percutaneously dilated a tight, localized stenosis of the superficial femoral artery (SFA) in an 82-year-old woman with painful leg ischemia and gangrene who refused leg amputation. After successful dilation of the stenosis with a guide wire and coaxial Teflon catheters, the circulation returned to her leg. The dilated artery stayed open until her death from pneumonia two and a half years later. Charles Dotter is commonly known as the "Father of Interventional Radiology" and was nominated for the Nobel Prize in medicine in 1978.

The first coronary angioplasty on a waking patient was performed by German cardiologist Andreas Gruentzig in September 1977.

Causes of Coronary Artery Disease

Blockages in the arteries may be caused by hypertension, diabetes, sedentary lifestyle, smoking, high cholesterol levels, diets high in saturated fats, and cardiovascular disease. Removing blockages is done with angioplasty.

Angioplasties are safer than bypass surgery; less than 1% of people die from complications after this procedure. Complications that may occur after or during an angioplasty:

• Tearing of the artery, resulting in total blockage and possible myocardial infarction; this can usually be repaired with a stent
• dislodging of a clot, which may cause a stroke in some circumstances (in less than 1% of patients who undergo angioplasties)
• Bleeding or bruising where the catheters were inserted
• Kidney problems, especially in people with underlying kidney disease and diabetes. This is caused by the iodine contrast dye used for the X-ray; intravenous fluids and medications can be given before and after the procedure to reduce this risk.
• Arrhythmia (irregular heartbeat);
• Allergic reaction to the dye given during the angioplasty
• Myocardial infarction, which occurs in 3 to 5% the cases
• The artery closing down instead of opening up. This may necessitate emergency coronary artery bypass grafting during the procedure (2-4 percent of people).
• Restenosis—one of the most common complications of angioplasties, which consists in the gradual re-narrowing of the blood vessels within several weeks or months after the procedure. Some conditions increase the risk of developing this complication, e.g., hypertension, diabetes, angina or kidney disease.
• Blood clots (in-stent thrombosis) forming within stents hours or months after the procedure. These may cause myocardial infarction.

The risks associated with angioplasty are greater in

• patients older than 75 years,
• patients who suffer from diabetes or kidney disease,
• those who have extensive heart disease or blood clots in the heart arteries
• people with poor pumping function in their hearts
• women

Complications such as myocardial infarction, stroke or kidney problems are, however, among the rarest. The death rate among patients who have angioplasty is very small, about 0.1% (compared to 1% to 2% for routine bypass surgery).

In most cases, when the potential benefits and the expected risks are taken into account the choice to perform angioplasty is the right one. (risk-benefit ratio).

Limited value in stable patients

The value of angioplasty in rescuing someone having a heart attack (by immediately alleviating an obstruction) is clearly defined in multiple studies, but studies have failed to find reduction in hard endpoints for angioplasty vs. medical therapy in stable angina patients. The artery-opening procedure can temporarily alleviate chest pain, but does not contribute to longevity. The "vast majority of heart attacks do not originate with obstructions that narrow arteries".

A more permanent and successful way to prevent heart attacks in patients at high risk is to give up smoking, increase exercise/yoga and take "drugs to get blood pressure under control, drive cholesterol levels down and prevent blood clotting".

After the procedure

After angioplasty, most of the patients are monitored overnight in the hospital but if there are no complications, the next day, patients are sent home.

The catheter site is checked for bleeding and swelling and the heart rate and blood pressure are monitored. Usually, patients receive medication that will relax them to protect the arteries against spasms. Patients are typically able to walk within two to six hours following the procedure and return to their normal routine by the following week.

Angioplasty recovery consists in avoiding physical activity for several days after the procedure. Patients are advised to avoid any type of lifting, babysitting grandchildren or other strenuous physical activity for a week. Patients will need to avoid physical stress or prolonged sport activities for a maximum of two weeks after a delicate balloon angioplasty.

Patients with stents are usually prescribed an anticoagulant, clopidogrel, which is taken at the same time as acetylsalicylic acid (aspirin). These medicines are intended to prevent blood clots and they are usually taken for at least the first months after the procedure is performed. In most cases, patients are given these medicines for 1 year.

Patients who experience swelling, bleeding or pain at the insertion site, develop fever, feel faint or weak, notice a change in temperature or color in the arm or leg that was used or have shortness of breath or chest pain should immediately seek medical advice.

Peripheral angioplasty

Peripheral angioplasty refers to the use of a balloon to open a blood vessels outside the coronary arteries. It is commonly done to treat atherosclerotic narrowings of the abdomen, leg and renal arteries. PA can also be done to treat narrowings in veins, etc. Often, peripheral angioplasty is used in conjunction with peripheral stenting and atherectomy.

Coronary angioplasty

A coronary angiogram (an X-ray with radio-opaque contrast in the coronary arteries) that shows the left coronary circulation. The distal left main coronary artery (LMCA) is in the left upper quadrant of the image. Its main branches (also visible) are the left circumflex artery (LCX), which courses top-to-bottom initially and then toward the centre-bottom, and the left anterior descending (LAD) artery, which courses from left-to-right on the image and then courses down the middle of the image to project underneath the distal LCX. The LAD, as is usual, has two large diagonal branches, which arise at the centre-top of the image and course toward the centre-right of the image.

Main article: Percutaneous coronary intervention

Percutaneous coronary intervention (PCI), commonly known as coronary angioplasty is a therapeutic procedure to treat the stenotic (narrowed) coronary arteries of the heart found in coronary heart disease. These stenotic segments are due to the build up of cholesterol-laden plaques that form due to atherosclerosis. PCI is usually performed by an interventional cardiologist.

Treatment with PCI for patients with stable coronary artery disease reduces chest pain, but does not reduce the risk of death, myocardial infarction, or other major cardiovascular events when added to optimal medical therapy.

Renal artery angioplasty

Atherosclerotic obstruction of the renal artery can be treated with angioplasty of the renal artery (percutaneous transluminal renal angioplasty, PTRA). Renal artery stenosis can lead to hypertension and loss of renal function.

Carotid angioplasty

Carotid artery stenosis is treated with angioplasty and stenting for high-risk patients in many hospitals.

Cerebral arteries angioplasty

In 1983, the Russian neurosurgeon Zubkov and colleagues reported the first use of transluminal balloon angioplasty for vasospasm after aneurysmal SAH.

See also

• Angiogram
• Atherectomy
• Charles Dotter
• Interventional Radiology
• Vascular surgery
• Stent

External links

Angioplasty Procedure

• Angioplasty.Org, celebrating over a decade of independent cardiology news and education for patients and professionals.
• A BBC film showing angioplasty being used for primary percutaneous intervention.
• Angioplasty
• Cardiovillage, cardiovascular education online
• National Heart Lung and Blood Institute, Diseases and Conditions Index
• NYU Interventional Radiology Pictorial explanation of angioplasty and stenting