Angioplasty

Angioplasty
Error creating thumbnail: sh: /usr/local/bin/rsvg-convert: not found Balloon angioplasty
Specialty	{{#statements:P1995}}
ICD-9-CM	00.6, 36.0 39.50
MeSH	D017130

Angioplasty (or Balloon angioplasty) is an endovascular procedure to widen narrowed or obstructed arteries or veins, typically to treat arterial atherosclerosis. An empty, collapsed balloon, known as a balloon catheter, is passed over a wire into the narrowed locations and then inflated to a fixed size. The balloon forces expansion of the stenosis (narrowing) within the vessel and the surrounding muscular wall, opening up the blood vessel for improved flow, and the balloon is then deflated and withdrawn. A stent may or may not be inserted at the time of ballooning to ensure the vessel remains open.

The word is composed of the combining forms of the Greek words ἀγγεῖον angīon ‘vessel’/‘cavity’ (of the human body) and πλάσσω plasso ‘form’/‘mould’. Angioplasty has come to include all manner of vascular interventions that are typically performed in a minimally-invasive or percutaneous method.

Uses

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 buildup 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.

Peripheral angioplasty

Peripheral angioplasty refers to the use of a balloon to open a blood vessel outside the coronary arteries. It is commonly done to treat atherosclerotic narrowings of the abdomen, leg and renal arteries caused by peripheral artery disease. Often, peripheral angioplasty is used in conjunction with peripheral stenting and a atherectomy.

Carotid angioplasty

Main article: Carotid artery stenting

Carotid artery stenosis is treated with angioplasty in a procedure called carotid stenting for patients at high-risk for carotid endarterectomy.

Renal artery angioplasty

Atherosclerotic obstruction of the renal artery can be treated with angioplasty with or without stenting of the renal artery. Renal artery stenosis can lead to hypertension and loss of renal function.

Venous angioplasty

Angioplasty is occasionally used to treat venous stenosis, such as stenosis of the subclavian vein caused by thoracic outlet syndrome.

Contraindications

Angioplasty requires an access vessel, typically the femoral or radial artery or femoral vein to permit access to the vascular system for the wires and catheters used. If no access vessel of sufficient size and quality is available, angioplasty is contraindicated. Small diameter, the presence of posterior calcification, occlusion, hematoma, or a bypass origin may all render a vessel inadequate to serve as an access point to the vascular system.

Technique

Access to the vascular system is typically gained percutaneously (through the skin, without a large surgical incision). An introducer sheath is inserted into blood vessel via the Seldinger technique. Fluoroscopic guidance and radiopaque contrast dye are used to guide angled wires and catheters to the region of the body to be treated. To treat a narrowing in a blood vessel, a wire is passed through the stenosis in the vessel and a balloon on a catheter is passed over the wire and into the desired position. The positioning is verified by fluoroscopy and the balloon is inflated using water mixed with contrast dye to 75 to 500 times normal blood pressure (6 to 20 atmospheres). A stent may or may not also be placed.

At the conclusion of the procedure, the balloons, wires and catheters are removed and the vessel puncture site is treated either with direct pressure or a vascular closure device.

Risks and complications

Relative to surgery, angioplasty is a lower-risk option for the treatment of the conditions for which it is used, but there are unique and potentially dangerous risks and complications associated with angioplasty:

• Embolization, or the launching of debris into the bloodstream
• Arterial rupture from over-inflation of a balloon catheter or the use of an inappropriately large or stiff balloon, or the presence of a calcified target vessel.
• Hematoma or pseudoaneurysm formation at the access site
• Radiation Injuries Radiation induced injuries (burns) from the X-Rays used

Angioplasty may also provide a less durable treatment for atherosclerosis, and be more prone to re-stenosis, relative to vascular bypass or coronary artery bypass grafting.

Recovery

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 is 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 of avoiding physical activity for several days after the procedure. Patients are advised to avoid any type of lifting, 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.

After the initial two week recovery phase, most angioplasty patients can begin to safely return to low-level exercise. A graduated exercise program is recommended whereby patients initially perform several short bouts of exercise each day, progressively increasing to one or two longer bouts of exercise. As a precaution, all structured exercise should be cleared by a cardiologist before commencing.

Patients with stents are usually prescribed an antiplatelet, 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 one 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.

History

Diagram of a balloon catheter.

Angioplasty was first 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 percutaneous coronary angioplasty on an awake patient was performed in Zurich by the German cardiologist Andreas Gruentzig on September 16, 1977.

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

Ingemar Henry Lundquist invented the over the wire balloon catheter that is used in the majority of angioplasty procedures in the world.

External links

• Angioplasty.Org, celebrating 17 years of independent cardiology news and education for patients and professionals.
• Video from Angioplasty.Org about the first coronary angioplasty, including interview with the patient - from the full-length documentary, "PTCA: A History"
• A BBC film showing angioplasty being used for primary percutaneous intervention.
• National Heart Lung and Blood Institute, Diseases and Conditions Index
• NYU Interventional Radiology Pictorial explanation of angioplasty and stenting
• Coronary Heart DIsease Info-drama with Angioplasty procedure information and illustrations