Endovascular Therapy (Catheterization Procedures)
Endovascular therapy—the treatment of vascular disease from inside the blood vessel—has changed the way heart attacks, stroke and other vascular conditions are being treated. Many vascular problems that once required invasive surgery can now be treated from inside the body. Because endovascular procedures are less invasive, patients spend less time in the hospital, less time recovering and often have less pain.
Endovascular therapy uses minimally invasive, catheter-based procedures and specialized equipment and techniques. These procedures require only a small incision, through which a thin catheter is inserted. Using advanced imaging technology, the catheter is guided through a blood vessel to remove blockages and open narrowed areas. Today, smaller, more flexible catheters and stents (small tubes) are being used to treat even the smallest blood vessels.
Opening Blocked Arteries
To open blocked coronary arteries, the following catheterization procedures may be performed.
Percutaneous transluminal coronary angioplasty (PTCA), also called balloon angioplasty, is one of the most common procedures for opening obstructed coronary arteries.
- Percutaneous refers to accessing the blood vessel through the skin.
- Transluminal means the procedure is performed through the blood vessel.
- Coronary refers to the coronary arteries, the vessels that supply the heart with blood.
- Angioplasty is the enlarging of a narrowed blood vessel.
PTCA is performed by advancing a slender, balloon-tipped catheter from an artery in the groin to an artery of the heart. The balloon at the tip of the catheter is then inflated, compressing the plaque in the coronary artery and widening the artery so that blood can flow more easily.
Stent placement for blocked arteries and aneurysms — during an angioplasty procedure, a metal stent is often placed in an artery after it is opened by the balloon; stents are flexible, wire mesh tubes that prop open arteries.
Carotid artery stenting, a new procedure that offers an alternative to patients considered high-risk for carotid artery surgery. The body’s two carotid arteries, located in the front of the neck, provide blood from the heart to the brain. When the carotid artery narrows due to a buildup of plaque, blood flow to the brain is reduced and a stroke can occur.
This procedure involves placing a stent in a blocked carotid artery to push plaque out of the way and restore blood flow. Stenting is meant to prevent stroke or recurrent stroke in patients with significant blockage in their carotid artery. To date, the FDA has approved two types of carotid stents, and both are available at Froedtert & the Medical College of Wisconsin.
A stent is a metallic mesh device that remains permanently in place to help keep the carotid artery open. Usually, a tiny catheter is inserted through the femoral artery at the top of the leg and threaded to the carotid artery. The catheter dilates the artery with a balloon and the stent is inserted. The stent is specifically designed for the carotid artery and includes filters that act as a “safety net” and prevent plaque from breaking off and going to the brain — and potentially causing a stroke — while the stent procedure is being performed.
For patients who are not candidates for the minimally invasive stenting procedure, carotid endarterectomy, an open surgical procedure, may be performed.
Renal artery angioplasty and stenting to relieve a blockage in the renal artery, the main blood vessel to the kidney, without surgery. A catheter inserted through a blockage in an artery, and a balloon on the catheter is inflated to open up the blockage and allow more blood to flow through it. Kidney arteries often require the insertion of a stent to keep the arteries open after the procedure. This procedure is performed by a vascular and interventional radiologist.
A procedure for opening an artery by removing the plaque produced by the build-up of cholesterol and other fatty substances inside an artery from atherosclerosis (“hardening of the arteries”). A catheter is inserted into the artery and, using special devices placed in a catheter, the physician is able to cut, grind, ablate or vaporize plaque from inside arteries or veins.
The catheter may have a laser that vaporizes the plaque, a rotating shaver on the end of the catheter, or a device that shaves off the plaque. Balloon angioplasty or stenting may then be done after the atherectomy. If atherectomy cannot be done as a catheterization procedure, a vessel can be opened as a surgical procedure in an operating room.
Thrombolysis is a catheter-based treatment that removes abnormal blood clots that restrict blood flow. Thrombolytic therapy dissolves blood clots using medication given directly into the clot through a catheter. Mechanical thrombolysis breaks up a blood clot using various mechanical devices. An interventional radiologist can use either of these methods to dissolve and remove blood clots.
Structural Problem Procedures
For structural problems of the heart, the following catheterization procedures may be used.
A procedure to widen a narrowed heart valve; a catheter is advanced through a blood vessel through the aorta and into the heart; the catheter is placed in the valve to be opened, and a large balloon at the tip of the catheter is inflated until the flaps of the valve open (performed by an interventional cardiologist).
PFO and ASD Closures
Patent foramen ovale (PFO) and atrial septal defect or (ASD) are holes or defects in the wall (septum) between the atria, the two upper chambers of the heart; to guide the closure of these defects with a special device, transesophageal echocardiography (TEE) is performed in the Cardiac Catheterization Laboratory.
Procedures extending or performed through or across the septum, the wall between the right and left sides of the heart.