Atherosclerosis, a condition in which fatty deposits of plaque build up along the inner walls of arteries, is a condition that may increase the risk of having a heart attack. Previous studies have shown that the presence of a specific kind of plaque, known as vulnerable plaque, is often found in people who have had a heart attack. This study will use a new imaging technique called optical frequency domain imaging (OFDI) to examine the presence of vulnerable plaques in people with coronary artery disease.

Brief Title

Identifying Vulnerable Plaques in Blood Vessels of the Heart Using a New Imaging Technique

Official Title

Natural History of Vulnerable Coronary Plaques

Brief Summary

Atherosclerosis, a condition in which fatty deposits of plaque build up along the inner walls <br /> of arteries, is a condition that may increase the risk of having a heart attack. Previous <br /> studies have shown that the presence of a specific kind of plaque, known as vulnerable <br /> plaque, is often found in people who have had a heart attack. This study will use a new <br /> imaging technique called optical frequency domain imaging (OFDI) to examine the presence of <br /> vulnerable plaques in people with coronary artery disease.

Detailed Description

Atherosclerosis is a condition in which deposits of fat, cholesterol, and other substances
build up along the inner walls of arteries; these deposits are known as plaque. As plaque
builds up, it increases the risk of heart attack. Previous autopsy studies have shown that
vulnerable plaques, a type of atherosclerotic plaque, are commonly found in people who have
had a heart attack. Until recently it has been difficult to identify vulnerable plaques in
people prior to their death. Many people who have coronary artery disease and are at risk of
having a heart attack undergo angioplasty, a procedure that opens a narrowed or blocked blood
vessel. During angioplasty, imaging devices are often used to take pictures of the inside of
blood vessels. The most commonly used imaging device, an intravenous ultrasound (IVUS)
catheter, is threaded through the blood vessels and uses sound waves to take pictures. An
OFDI is a new type of catheter that takes more detailed pictures of blood vessel walls and
plaques. The additional detail provided by OFDI images may improve detection of vulnerable
plaques, which may help physicians identify people who are at high risk of having a heart
attack. This study will use standard IVUS imaging and OFDI to examine vulnerable plaques
within blood vessels of the heart and to evaluate any changes that occur over time in heart
blood vessels and plaque.

This study will enroll people with coronary artery disease who are undergoing angioplasty. At
a baseline study visit, participants will first undergo an angiography procedure, in which
x-ray pictures will be taken of the heart blood vessels. Participants will then be randomly
assigned to undergo either the IVUS procedure followed by the OFDI procedure or vice versa.
Repeat angiographies will occur after each imaging procedure. Next, participants will undergo
angioplasty and a stent will be placed at the area of the blood vessel that is narrowed or
blocked to keep the blood vessel open. Finally, participants will undergo repeat IVUS and
OFDI procedures. For some participants, the study physician may perform the IVUS and OFDI
procedures only after the angioplasty. Every six months and for a period of two years,
participants will complete questionnaires about medication history and heart problems that
may have occurred since the baseline visit.Blood collection will occur if this is done during
office visit.

Outcome Measures

Outcome measures are the tests that investigators perform to prove whether or not a treatment being tested in a clinical trial is having any effect.