Lahey Clinic's Heart And Vascular Center, Burlington, Mass.

Hi, I'm Richard Nesto, Chair of Cardiovascular Medicine, Co-Principal Investigator of the INTENSIVE (Intensive Insulin Therapy and Size of Infarct as a Validated Endpoint by Cardiac MRI) trial and a principal investigator of the NIH-supported BARI-2D, the largest study ever conducted on heart disease and diabetes.

As part of an internationally renowned academic medical center affiliated with Tufts University School of Medicine, Lahey Clinic's Heart and Vascular Center offers patients state-of-the-art care in a setting of clinical scholarship and research. Our main focus is on trials that directly impact patient care and expose patients to the latest advances in treatment.

Heart Attacks and Glucose Levels

Lahey Clinic has a major role in a landmark study examining whether lowering elevated glucose levels in patients with heart attacks reduces the risk of death or other serious heart damage. The study is called the INTENSIVE (Intensive Insulin Therapy and Size of Infarct as a Validated Endpoint by Cardiac MRI) trial. Patients at 60 medical centers in North and South America will participate in the two-year study, set to begin this month. Lahey Clinic is a vanguard center, which means it has a key role in developing and refining the final protocol for the trial.

We already know that people with high blood sugar do less well than those with normal sugar levels during or following a heart attack. What we are trying to determine in the INTENSIVE trial is if we lower the sugar with intravenous insulin, does this remove or lower the risk to the patient, resulting in less heart damage or lower likelihood of death?

In order to answer this question, researchers will be administering insulin to patients with high glucose levels during or following a heart attack. The administration of insulin will follow two strategies: some patients will be given a dose of intensive, long-acting insulin, while others will be given a lower dose of insulin, predominantly subcutaneously. Researchers will examine if this difference has an effect on outcome.

At 60 days following the heart attack, patients will have an MRI to examine the structure of the heart. If we find that insulin reduces the amount of heart damage, this will become a new standard of care in treating heart attacks. In addition, researchers are studying whether insulin has added therapeutic benefit.

Lahey's Cardiovascular Medicine Department has a long track record of involvement in landmark clinical trials evaluating different treatments for patients with diabetes, including the NIH-supported BARI-2D, the largest study ever conducted on heart disease and diabetes.

Identifying Plaques that Cause Heart Attacks

Heart attacks occur when the blood supply to the heart muscle itself is severely reduced or stopped due to the formation of plaque -- deposits of fat-like substances -- in one or more of the coronary arteries.

By using a number of light-based, imaging technologies, Lahey cardiologists are participating in pioneering studies to identify the plaques that put patients at a higher risk of heart attack. One of these technologies is near-infrared spectroscopy.

"The idea behind spectroscopy is that different substances reflect and absorb light differently," explains Sergio Waxman, MD, director of interventional cardiology research at Lahey. "These patterns provide information about the chemical composition of matter. For instance, the probes that are sent to Mars to examine the composition of rocks use spectroscopy." Along with five other centers in the U.S. and Canada, Lahey Clinic recently completed the first study in the world to look at the ability of this technology to detect fatty plaques in patients who were scheduled for an angioplasty procedure.

Lahey physicians are also using a technology called angioscopy to distinguish the properties of different plaques. Angioscopy allows physicians to use a camera and put a tiny lens inside an artery to look at and measure the color of different plaques as a means of detecting their potential risk. "Lahey is currently one of few places working on this type of computerized color analysis," says Waxman. "We can quantify the color of a plaque that hopefully can identify which plaques are likely to be more dangerous than others."

Finally, in conjunction with Massachusetts General Hospital, Lahey researchers are exploring optical frequency domain imaging, or OFDI. By using a specialized catheter, physicians can obtain detailed information about the inside of an artery with a level of resolution similar to that of a microscope. The first few cases have been performed at Lahey as part of an ongoing multi-center study.

"Eventually, we'd like to use any of these technologies to screen patients at the time of an angiogram or angioplasty," says Waxman. "By identifying the composition of certain plaques, we could learn whether more aggressive and targeted treatments -- with medication or with stents -- would prevent heart attacks."