Commonly Asked
Questions and Answers
About Transmyocardial
Laser Revascularization

Dr. Mahmood Mirhoseini, and his research associate, Mary Cayton, R.N., have developed a technique called Transmyocardial Laser Revascularization (TMLR). The following questions and answers will give you a better understanding of TMLR and how it works. Simply click on your desired question to view a complete answer.

1.) What is TMLR?

2.) How exactly does it work?

3.) How does TMLR compare with other procedures like coronary bypass surgery or balloon angioplasty?

4.) Is TMLR similar to laser angioplasty?

5.) Why would a patient need TMLR rather than coronary bypass surgery or balloon angioplasty?

6.) If a patient has already had coronary bypass surgery or balloon angioplasty, can he or she still be eligible for TMLR?

7.) What about recovery time?

8.) Will insurance cover TMLR?

9.) How did St. Luke's become involved in the TMLR Program?

10.) How does a patient qualify for TMLR?

11.) Where can I call to get more information on TMLR?


1.) What is TMLR?

    In this surgical procedure, a carbon dioxide laser is used to create tiny openings through the wall of the heart muscle. The openings, about the size of a pencil lead, allow blood to seep into the heart muscle from the inner chamber and function as new blood vessels.


2.) How exactly does it work?

    If a patient is a candidate for the procedure, Dr. Mirhoseini first determines through extensive preoperative studies what areas of the heart lack blood supply. He then makes an incision into the left side of the chest. Once the heart muscle is exposed, he fires a computer- controlled carbon dioxide laser between the patient's heartbeats. The laser fires when the left ventricle is full of blood. This prevents the laser beam from continuing through the heart since carbon dioxide laser energy is absorbed and dispersed by the liquid.
    Each laser burst creates a permanent opening or channel between the damaged area and the left ventricle. Dr. Mirhoseini creates between 15 to 30 channels through the wall of the heart leading into the left ventricle. These channels can be made quickly with little damage to the surrounding tissue. They become like new blood vessels, carrying oxygen-rich blood through the channels to the areas of need in the heart muscle.


3.) How does TMLR compare with other procedures like coronary bypass surgery or balloon angioplasty?

    With coronary bypass surgery, surgeons must cut through the sternum and open the rib cage while the patient is hooked up to a heart-lung bypass machine. This allows the surgeons to temporarily stop the flow of blood through the heart and lungs during surgery. The machine works like a heart and lungs, allowing oxygen to circulate, although the heart does not beat. The TMLR procedure is sometimes done in conjunction with bypass surgery. As a standalone procedure, TMLR requires making an incision on the side of the rib cage between the ribs rather than in the sternum, which can lead to a faster recovery.
    Balloon angioplasty requires making a small incision or needle puncture and inserting a tiny balloon catheter through an incision in the arm or groin area, which is then threaded into the coronary arteries and inflated to flatten plaque against the arterial walls.
    Investigational studies have shown that channels cut by lasers during TMLR have remained open and that these channels also protect the heart muscle.


4.) Is TMLR similar to laser angioplasty?

    Laser angioplasty is performed in conjunction with balloon angioplasty. When an artery is severely blocked, a laser catheter is used to dissolve plaque directly in the artery by using lasers prior to inserting the balloon.
    Laser angioplasty is separate from and unrelated to TMLR.


5.) Why would a patient need TMLR rather than coronary bypass surgery or balloon angioplasty?

    Some patients are at high risk or ineligible for coronary bypass surgery or balloon angioplasty. Patients who can benefit from TMLR include those who have diffuse disease (small vessel disease of many arteries), severe diabetics who are prone to small vessel disease, those who require bypass at a young age and patients who have failed to get relief from other methods of treatment.


6.) If a patient has already had coronary bypass surgery or balloon angioplasty, can he or she still be eligible for TMLR?

    Yes. TMLR can be performed on patients who have failed to get relief from coronary bypass surgery or balloon angioplasty.
    A patient who has only had TMLR performed can still undergo bypass surgery in the future.


7.) What about recovery time?

    Patients can expect to remain hospitalized for an average of five days following TMLR surgery. Follow-up visits are conducted at 3-month intervals the first year following surgery. These visits are important since they determine the results of the investigative procedure as well as help in treating other patients. Patients are expected to participate in all follow-ups.


8.) Will insurance cover TMLR?

    Insurance coverage is handled on an individual, case- by-case basis. Fees can include the medical center and surgery separately as well as the attending physicians, consulting physicians and other members of the medical staff.
    As TMLR is still considered an investigational procedure, some insurance companies agree to cover all areas, some only cover specific portions, while others provide no coverage at all. Certain costs, such as travel expenses, are the patient's full responsibility. Our staff makes every effort to work with and secure the cooperation of the insurance carrier.
    At St. Luke's, patients are treated regardless of their ability to pay.


9.) How did St. Luke's become involoved in the TMLR Program?

    Dr. Mirhoseini began exploring the use of lasers to increase blood flow to the heart in the late 1960s, prior to the widespread use of bypass surgery.
    Throughout the next 15 years, Dr. Mirhoseini and his research associate, Mary Cayton, conducted clinical studies to evaluate the safety and effectiveness of laser channels in the heart. Studies showed that the laser channels remained open, the surrounding tissues experienced little or no damage and the outer wall of the heart was protected from ischemia (lack of blood flow to the heart).
    In 1985, Dr. Mirhoseini performed TMLR in conjunction with bypass surgery at St. Luke's Medical Center. As a result of this TMLR work, 18 of the 20 patients with advanced heart disease who were treated remain alive today, an average of seven to eight years after surgery. Two of the patients subsequently died of unrelated causes. Autopsy results revealed the laser channels had remained open and formed vessel-like walls.
    To date, Dr. Mirhoseini has performed the vast majority of TMLR procedures worldwide.


10.) How does a patient qualify for TMLR?

    A potential candidate must first be diagnosed as high risk or ineligible for other methods of treatment, such as coronary bypass surgery or balloon angioplasty. In addition, candidates that have previously undergone other treatments and have seen no improvement are also considered.
    Prior to coming to St. Luke's Medical Center, a patient's medical records should be sent in advance and should include a history and physicals, angiograms, prior surgery and post-operative reports. Once a candidate comes to St. Luke's, he or she must still qualify for the TMLR procedure based on clinical evaluation and diagnostic testing. In some cases, other methods may still be recommended over TMLR.


11.) Where can I call to get more information on TMLR?

Heart and Lung Institute N124 W16862 Lovers Lane Germantown, WI 53022

heartlung@globaldialog.com



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