Heart Surgery

The Southern Illinois University School of Medicine has been performing laser heart surgery since 1997. The school was one of a few centers throughout the United States which participated in the initial clinical investigation of this device. Transmyocardial laser revascularization was approved for clinical use by the FDA on August 20, 1998.

What is transmyocardial revascularization?

Transmyocardial revascularization (TMR) is a new surgical procedure. It employs a high-energy, computer-synchronized carbon dioxide (CO2) laser to place channels through oxygen deprived heart muscle (myocardium). Clinical studies have demonstrated that the creation of these channels provides oxygen-rich blood to the previously deprived areas of the heart. TMR is prescribed for patients for whom bypass surgery and angioplasty are no longer appropriate.

How does this procedure work?

TMR is performed on a beating heart, generally through a small left chest incision, called a left thoracotomy. The surgeon uses the one-pulse of the laser system to create between 20 and 40 one millimeter-wide channels into the left ventricle of the heart. The computer-controlled laser is synchronized with the heartbeat and is triggered to fire when the ventricle is filled with blood and the heart is relatively still and likely insensitive to stimuli.

What is the history of TMR?

Interestingly, the concept of creating channels for cardiac circulation is modeled after the reptile heart. Unlike the human heart, which is nourished by blood flowing in arteries located on the outside of the heart muscle, the reptile heart is primarily nourished by internal channels that supply blood from the heart chamber into the myocardium or heart muscle. In the 1960s, it was conceived that laser could be used to create similar channels in ailing human hearts. It is now general accepted that the laser channels do not stay open, but promote the growth of new blood vessels.

How does TMR, using the heart laser, differ from angioplasty and bypass surgery?

At this stage, TMR using a laser system is a treatment for patients for whom angioplasty and bypass are no longer alternatives, or it may be used in combination with coronary artery bypass surgery for areas of the heart that can not be treated with bypass. The procedure differs from both in a variety of ways. It appears to avoid the restenosis (re-narrowing of arteries) of angioplasty and bypass surgery, since it is believed to create new blood pathways with the heart muscle. It is also less invasive than traditional bypass surgery in that it generally involves a small left chest incision, typically does not necessitate a blood transfusion, and, because it is performed on a beating heart, does not require the use of a heart-lung machine, which bypass surgery usually necessitates. As a result, recovery is potentially quicker and less traumatic than in open-heart procedures. TMR may also be used with traditional bypass surgery if the person has areas of the heart that would benefit from both procedures.

Who is the patient for TMR?

Candidates for TMR are patients with severe coronary artery disease (CAD) that has not improved despite maximal drug therapy. These people have severe angina that is not treatable with angioplasty or bypass surgery. In fact, many of the candidates have already had bypass surgery and/or angioplasty procedures. Severe CAD patients typically experience excruciating chest pain and possibly shortness of breath and fatigue. They lead severely restricted lives and simple tasks, such as showering or walking a short distance, seem impossible.

Is this procedure covered by insurance?

Many, but not all insurance companies cover the procedure; however, the SIU staff can help patients obtain pre-admission authorization from their insurance carrier prior to the surgery just to be sure. Medicare recently classified TMR for angina as non-experimental and covers fees for this procedure.
Persons with questions may call the Cardiothoracic Surgery office at this number. 217-545-7422

On-Going Research

IMPROVED RADIAL ARTERY PRESERVATION FOR CORONARY ARTERY BYPASS
Evaluates the best method of preservation for this arterial conduit used in bypass surgery.

EFFICACY OF SUPPLEMENTAL MAGNESIUM
Studies the effects of magnesium given in and after surgery on the incidence of arrhythmias (irregular heart beats).

TRANSMYOCARDIAL LASER REVASCULARIZATION
Studies a new method using an Nd: YAG laser to create arterial channels in the heart to improve blood supply to ischemic areas of the muscle.

PREVENT IV
A multi-institutional study evaluating genetic modification of vein grafts for coronary artery bypass.

ANTICOAGULATION AT HOME
Evaluates the use of home monitoring of anticoagulation to see if it works and is safe.