Coronary artery disease is the leading cause of death in America and affects more than 13 million of us. More commonly known simply as ‘heart disease’, coronary artery disease develops when fat and calcium deposits (known as plaque) build up within the walls of the arteries that supply blood to the heart muscle, which can restrict the flow of blood. Without proper blood flow, the heart cannot get the oxygen and nutrients it needs to function. Many patients with this disease suffer symptoms such as chest pressure or pain, shortness of breath, heart attack, or congestive heart failure, but some patients may have no symptoms at all despite having serious heart blockage.
Once an important heart artery becomes about 70 percent blocked we generally recommend treatment to restore blood flow to that portion of the heart, a procedure known as revascularization. Revascularization is accomplished by means of either open heart surgery (also known as bypass surgery) or by the insertion of stents, which do not require surgery. Stents are small, thin slotted tubes of metal that are placed within the blocked artery via a catheter inserted through a small incision in the groin or arm. The stent pushes the blockage aside and restores normal blood flow to the affected portion of the heart. Bypass surgery involves opening the chest and stitching in pieces of vein or artery to create a new channel for blood to flow around the blockage.
Until recently, stents were used only for simple blockages in easily accessible arteries, while more advanced cases of heart disease often required bypass surgery. Today, however, stent technology has come a long way. Improvements in stent and catheter technology have increased the effectiveness of stents for patients who would have previously only been candidates for open heart surgery.
The most significant innovation has been the development of drug-coated stents. These slowly release a medication into the artery wall to help reduce the chance of scar tissue formation within the stent. Historically, one of the downsides to stents has been the potential for scar tissue formation within the stent due to an exaggerated healing process that occurs within the arteries of some patients (known as restenosis). If a significant amount of scar tissue forms, the artery may again become substantially narrowed and a repeat angioplasty procedure may become necessary. The latest drug-coated stents have a dramatically decreased risk of scar tissue formation as compared to earlier generations of non-drug coated stents, and a number of recent studies have found that these stents work quite well even for more complex blockages in which surgery would have been the only considered option in the past.
Although some media reports have linked drug-coated stents to an increased risk of blood clot formation that can lead to heart attacks, much of this appears to be related to patients discontinuing their blood-thinning medications inappropriately. As long as patients take their blood-thinning medications as directed by their physician, the risk of blood clot formation within the stent is actually very low.
Another technological advancement has been in the construction of the stent itself. Early stents were often difficult to place into the arteries, which limited their use to the treatment of simple blockages. The newest generation of stents is constructed of a thinner, more flexible metal and can be delivered into arteries that are more tortuous or twisty. Since it is easier for us to get the stents delivered to the blockage, we are now able to do more complicated work.
Another major innovation has occurred in the development of guidewires and other technologies to facilitate the opening of totally blocked heart arteries.The presence of a totally blocked artery was previously one of the major reasons that a given patient would be sent for bypass surgery, however newer wires, catheters, and techniques have enabled even very complex procedures to be performed safely and effectively.
Because stenting is a minimally invasive treatment, patients generally spend just one night in the hospital for observation. Recovery is faster and less painful than with open heart surgery, and there is a lower risk of complications such as respiratory complications, stroke, and wound infections.
Of course, neither stenting nor open heart surgery is perfect and each has pros and cons. With both treatments, there is a chance that another revascularization procedure may be needed down the road, and the first procedure a patient has may influence the options the second time around. Data shows that five years after open heart surgery, about 50 percent of vein bypass grafts have become blocked. At this point, the patient can have another bypass surgery (which carries a higher risk the second time around) or can be treated with a stent. However, it can be more challenging to successfully place stents after open heart surgery. Statistically speaking, patients who have stents placed as their initial treatment have a higher chance of requiring another revascularization procedure than those who have bypass surgery, but each repeat stent procedure is less difficult on the patient, and the risk is far lower than the risk of open heart surgery.
Every patient is different and unique, and the best approach to management depends on your individual health profile. If you have heart disease, your physician will help determine the best treatment for you.
Curtiss Stinis, MD, is an interventional cardiologist with Scripps Memorial Hospital La Jolla. Join Dr. Stinis as he discusses the newest treatment and technology care for your heart at a free seminar on Thursday, January 28, 2010 at 6 p.m. at the Schaetzel Center on the Scripps La Jolla campus. Please register by calling 1-800-SCRIPPS (1-800-727-4777).
Media Contact: Lisa Ohmstede