Transmyocardial revascularization (TMR): current status and future directions

Area of Science:

• Cardiovascular Surgery
• Interventional Cardiology
• Medical Technology

Background:

• Diffuse coronary artery disease (CAD) presents complex challenges for cardiac surgeons.
• Patients with refractory CAD often face limited treatment options and increased risks.

Purpose of the Study:

• To review the clinical science of transmyocardial revascularization (TMR).
• To emphasize results from randomized controlled trials (RCTs) evaluating TMR.
• To explore TMR's role in managing diffuse CAD.

Main Methods:

• Review of RCTs assessing TMR as sole therapy and in conjunction with coronary artery bypass grafting (CABG).
• Inclusion of basic science papers on TMR mechanisms.
• Consideration of future directions, including cell-based therapies.

Main Results:

• Two FDA-approved laser systems (Ho:YAG and CO2) deliver TMR to unrevascularizable left ventricular areas.
• TMR can be used as a standalone procedure or adjunct to incomplete CABG.
• Practice guidelines support TMR for diffuse CAD patients.

Conclusions:

• Incomplete revascularization in diffuse CAD increases operative and long-term cardiac risks.
• RCTs demonstrate operative and long-term benefits of sole and adjunctive TMR.
• TMR use is supported for this challenging patient population.