The Sanger Clinic is one of the largest academically and research affiliated heart centers in the country, and provides the latest interventional technology for treatment of heart disease in the Southeast. Utilizing long, flexible, hollow tubes, called catheters, Sanger cardiologists deliver specialized tools and medicines to diagnose and treat heart disease non-surgically.

The first step is a diagnostic picture of the arteries, called a coronary arteriogram or catheterization. The physician then threads a catheter through the entry site and follows the main artery in the body, called the aorta, up and around into the opening of the left, or right, coronary artery. Through this hollow catheter, the physician injects a small amount of special dye, called contrast, which, when viewed in motion under X-rays, reveals any obstructions or plaques located within the coronary vessels.

Depending on the number, severity and location of these obstructions, the physician may refer the patient for medical therapy, bypass surgery, or, if appropriate, may treat the patient directly, using catheter-based techniques. These options are discussed with the patient after the diagnostic catheterization. Upon occasion, the cardiologist may suggest transforming the diagnostic test on the spot into a therapeutic procedure.

The cardiologist places a more versatile catheter into the opening of the coronary artery. A thin wire is threaded through this catheter and well past the narrowing, or stenosis, in the artery. A number of therapeutic devices can be passed safely over the wire and positioned precisely at the obstruction.

Balloons comprise the majority of interventional procedures. These devices are inflated to compress the plaque against the artery wall in a procedure known as "angioplasty", sometimes called "balloon dilatation", sometimes "PTCA" (percutaneous transluminal coronary angioplasty).

Angioplasty balloon catheters come in a wide range of lengths and diameters, and are made from a variety of materials, but the major shared characteristic is that the balloon can inflate to a certain diameter and not beyond, thus allowing a predictable opening. The positioning of the balloon at the stenosis, its inflation and the resulting increased flow post-angioplasty are all carefully viewed under fluoroscopy by the interventionist. Several inflations are usually made before the procedure is considered finished.

In more than 70% of interventions today, a stent (a tiny metal structure which comes in a variety of sizes and designs) is also used, usually following a balloon angioplasty. Sometimes the stent is used as the initial therapy, called "direct stenting." There are currently clinical trials being conducted to determine the benefits of direct stenting over balloon-plus-stent.

A new type of stent, the drug-eluting stent or DES, has become the standard interventional therapy. The drug-eluting stent is a bare metal stent that is coated with a slow-to-moderate-release drug formulation, sometimes embedded in a polymer. When the stent is placed, the drug is released over time directly to the area most likely to reblock. This new stent is now reducing reblockage to under 5% and reducing bypass surgery by 20-30%.

Some catheter-based devices actually remove the plaque itself, a process known as atherectomy, or ablation. There are a number of different types. One works like a shaver, cutting the soft plaque from the obstruction site and depositing it in a capsule which is then withdrawn. Another model cuts the plaque and suctions it away.

If the plaque has hardened, and become calcified, the interventional cardiologist can use a device, called a rotational atherectomy catheter: an olive-shaped diamond burr which rotates at extremely high speed and works like a sander to pulverize the obstruction into harmless microscopic particles that are washed away by the blood.

The emergency treatment of heart attack, or acute myocardial infarction, has been dramatically affected by these interventional devices. The combined use of balloons, stents, and a variety of new drugs literally can stop a heart attack in its tracks by quickly dissolving the clot, or thrombus, opening up the obstruction, and restoring normal blood flow - minimizing damage to the heart muscle itself.