Transmyocardial laser revascularization (TMR) is a new surgical procedure used to treat inoperable heart disease in people with persistent angina which cannot be relieved by any other method like angioplasty, stenting, coronary bypass surgery and medications. It improves blood flow with a special carbon dioxide laser by creating small channels in the heart muscle.
A good candidate for TMR is a person who has:
- Severe angina
- A history of previous bypass surgery or angioplasty,
- Pre-operative test that shows decreased blood supply to the heart muscle (ischemia) or a person who has been told by a doctor that there is nothing that can be further done to help their symptoms.
The procedure is often combined with bypass grafts surgery because the surgeon can bypass the targeted blockages and use the laser on the heart muscle to achieve a complete blood flow to the heart.
TMR is not suitable for patients with severely damaged heart muscle due to heart attacks or heart muscle with no areas of ischemia.
Before surgery, preoperative evaluations will be done which include cardiac catheterization to visualize coronary arteries and possible blockages and other tests to determine blood flow to heart muscle and the pumping ability like cardiac MRI, echocardiogram, positron emission tomography and Dobutamine echocardiography.
TMR is performed through a small incision in the middle or either the left side of the chest which exposes the heart muscle. With a carbon dioxide laser, between 20 to 40 one millimeter wide channels are created in the left ventricle of the heart between heartbeats when the ventricle is filled with blood and the heart is relatively still so arrhythmias can be prevented.
A doctor will decide how many channels are necessary. Inside areas of the channels remains open inside the heart to improve blood flow and outer areas are closed.
The procedure usually takes one to two hours and it may last longer if it is combined with other heart procedures.
Patient must stay in hospital 4 to 7 days and the length depends on overall health and rate of recovery of the patient.
After surgery, a supervised cardiac rehabilitation program is recommended to help guide patient's recovery and progress activity level of the patient.
A study published in 1999 by The New England Journal of Medicine showed that 72% of patients who had TMR experienced an improvement in angina symptoms (relief of chest pain, improved blood flow to the heart, improved quality of life and decreased hospital admissions) after 12 months, compared to only 13% patients who were receiving medications for the treatment of their angina symptoms.
TMR is covered by most insurance companies.