Heart disease is the leading cause of death in the U.S., killing one in four Americans every year, and researchers at the Stony Brook Heart Institute are now working at the forefront of the treatment of this disease.

Headed by Dr. Luis Gruberg, a professor in the Department of Medicine and co-director of the SBU Heart Institute, a clinical trial is currently being conducted to study the dynamics of a potential new type of cardiovascular stent.

When blood vessels in the heart become clogged, greatly increasing the risk of heart attack and death, there are two main types of treatment available.  Angioplasty is the practice of inflating a small balloon within the clogged vessel, expanding it and increasing blood flow.  However, in many cases, these blood vessels contract again, necessitating further treatment.

When the clog is severe or when angioplasty has failed, the second treatment option is a cardiovascular stent.  A stent is a small, metal mesh tube that is put in place to more permanently expand a narrowed vessel.  This treatment comes with its own set of complications, however.

Over time, cells in the blood vessel can grow over the stent, and in some cases, the blood vessel can become clogged all over again.

This issue led to the development of another form of stent currently being used by physicians.

Drug-eluting stents are coated in chemicals that prevent the growth of new cells.  These have solved the cell growth problem, drastically reducing the percentage of vessels that become reclogged after stent placement.

However, because no cells are growing around the stent, the bare metal leads to a greater incidence of blood clots forming.  Taking blood thinners, like aspirin, can help reduce the risk of blood clots, but if they do form, like clogged vessels, they can lead to heart attacks and death.

The next step in cardiovascular stent technology may be dissolvable stents.  Dissolvable stents are put into place, like their non-dissolvable counterparts, and remain in place for approximately two years.  However, over time, these stents dissolve, theoretically addressing both the cell growth and blood clot problems.

Created by Abbott, a pharmaceutical and health care product company, this new phase in the treatment of heart disease is currently undergoing phase three clinical trials.  These trials will be performed on 2500 patients across the United States and Dr. Gruberg expects to test the device on 30-40 patients here at Stony Brook.

Phase three is the final stage of clinical trials before the Food and Drug Administration decides whether the device is fit for public use.  Not all medical devices require FDA approval before they are marketed.  Stents, however, are classified as a class three device, the class representing the highest potential risk, which do require FDA approval.

The success rates for FDA approval of new drugs going through clinical trials are notoriously low with only about 9 percent of drugs in phase one trials making it all the way through phase three and FDA approval.  Out of the drugs reaching phase three trials, only 55 percent go on to receive approval.

Medical devices, like cardiovascular stents, have better odds, with slightly less than 50 percent of devices in phase one eventually achieving approval while 20 percent of those reaching phase three fail to gain FDA approval.

The fact that dissolvable stents have made it to phase three trials is a promising development for these devices, though their approval for public use is certainly not guaranteed.  Dr. Gruberg and his colleagues across the country will evaluate the safety and efficacy of dissolvable stents as well as the health of the vessels they are meant to repair.

It is important to note that angioplasty and stents alike treat symptoms of larger problems.  Dissolvable stents will not cure heart disease.  Lifestyle changes must follow stent placement or the vessels supported by the stent will likely become reclogged after it dissolves.  Both traditional and dissolvable stents help buy time for a patient to make the necessary changes that will lead to more sustainable health improvements.

If successful, dissolvable stents will greatly reduce the major health risks that come with current stent treatments.