Can a minimally invasive approach and a quicker patient recovery time following transmyocardial revascularization (TMR) via robotic assistance override some surgeons’ ambivalence about the procedure?

That ambivalence is the hump that small med-tech company CardioGenesis (Irvine, California) is attempting to cross, with upcoming roll-out of its PEARL (Port Enabled Angina Relief using Laser) 5.0 Robotic Delivery System.

“PEARL is the first minimally invasive TMR that uses robotic assistance,” Richard Lanigan, president of CardioGenesis told Medical Device Daily.

The company completed a 40-patient IED study for PEARL in February, and it received premarket application approval for the device earlier this month. It intends launch of the device during the annual meeting of the Society of Thoracic Surgeons (Chicago) in January.

Typically TMR procedures are used for patients suffering from angina or chest pains, but the history of TMR has been dogged by suspicions that it is no better than placebo and requires too much effort for debatable results.

CardioGenesis has continued to promote the procedure as worthwhile and now, with robotic aid, says it will be even more beneficial.

In TMR, a surgeon makes an incision on the left breast to expose the heart. Then, using a laser, a series of holes are punched into the heart’s pumping chamber to provide more channels for perfusion of blood.

From 20 to 40 one-mm laser channels are placed during the procedure. Bleeding from the laser channels on the outside of the heart stops after a few minutes of pressure from the surgeon’s finger.

This is how PEARL works:

The PEARL Robotic delivery system consists of the CrystalFlex fiber optic within a hand piece with an extended-length flexible shaft enabling it to be introduced through small incisions in the chest wall through a 5 mm port. The end of the flexible shaft is designed to enable the grasping and manipulation of the tip by surgical robotic tools within the chest cavity for placement on the surface of the targeted area of the heart muscle. The CrystalFlex fiber optic is then advanced through the flexible shaft into the heart muscle using the hand piece control to create a series of laser channels.

The system is designed for operation through a 5.0 mm port by the da Vinci surgical robotic system from Intuitive Surgical (Sunnyvale, California).

“The Cardiogenesis TMR system uses laser energy delivered through a small optical fiber to create channels in heart muscle that doesn’t have enough blood supply, thus helping patients with disabling chest pain or angina,” said Louis Brunsting III, MD, of the Centennial Medical Center, (Nashville, Tennessee), principal investigator for the PEARL investigational device exemption (IDE) clinical study.

“The PEARL 5.0 device now allows this form of treatment to be performed entirely endoscopically, with only a few port incisions. This new minimally invasive approach, utilizing a surgical robotic system, can markedly reduce hospitalization and recovery time for patients, facilitating their return to an active lifestyle.”

That recovery time is four days compared to the six to eight days it would take for a thoractomy incision to be made.

But will surgeons flock to PEARL?

“There are different challenges for robotic systems,” Lanigen said. “One of the issues is ahesions that remain from patients who have already had bypass surgery.”

The Cleveland Clinic has gone on the record and said that it didn’t use robotic assisted surgeries for TMR cases because scar tissue from previous surgeries often makes that option unfeasible, according to an article on www.partyhealth.net.

The Clinic, however, use robotic assistance for some other heart surgeries, according to the article.

So Lanigan makes no bones about the device facing some roadblocks, but he says that ultimately it will fill an important technology niche.

“FDA approval of the PEARL 5.0 is a significant achievement for Cardiogenesis and an important advancement for patients suffering from heart disease who are not candidates for coronary stents or bypass surgery,” Lanigan said. “Physicians can now offer the proven clinical benefits of TMR utilizing the less invasive approach via robotic surgical systems. We believe the PEARL 5.0 Robotic delivery system approval increases the number of patients who can be effectively treated with TMR.”

TMR procedures have become more frequent in the last two years thanks in part to hospital reimbursement rates for it by the Centers for Medicare & Medicaid Services (CMS; Baltimore) increasing by more than 14% (Medical Device Daily, Sept. 26, 2005).

TMR is used to treat advanced coronary artery disease in patients whose chronic angina symptoms are not relieved by medication and have an area of the heart that cannot be treated by percutaneous intervention or bypass surgery. The company cites studies in which three out of four patients who received TMR have shown a significant reduction in their angina pain. Additionally, patient benefits have been shown to endure beyond five years, and TMR has been shown to help patients live longer, according to CardioGenesis.

The procedure also has shown positive clinical benefits for patients who may require one or two bypass grafts, yet also have other areas of the heart that are not able to be bypassed by direct bypass-surgery. This is often seen in patients with diabetes.

TMR is not suitable for patients whose heart muscle is severely damaged due to heart attacks; the heart muscle is dead or scarred rather than affected by inadequate blood supply (ischemic) Heart muscle has no areas of ischemia (inadequate blood supply).