Medical Device Daily Executive Editor
WASHINGTON — Sunday's activities of the annual meeting of the American Association for Thoracic Surgery (Beverly, Massachusetts) offered attendees a look at the world of surgery for coronary arteries as seen through the eyes of an advocate of the hybrid approach to this area of repair, saying that the current divide between two camps is somewhat like living on a sinking ship.
John Byrne, MD, chair of the cardiac surgery department at Vanderbilt University Hospital (Nashville, Tennessee), discussed hybrid procedures, that is, those procedures that marry the minimal invasiveness of percutaneous coronary interventions (PCI) with the surgical invasiveness afforded by conventional coronary artery bypass grafts (CABG).
Byrne said that the hybrid paradigm is "not a new procedure or technique . . . but is a different way of thinking."
He said that the hybrid approach — around for awhile but not commonplace — requires close collaboration between interventionalist and the cardiac surgeon, working together in the operating room (OR).
Hybrid surgery was first tried out in the mid-1990s, when minimally invasive direct coronary artery bypass (MIDCAB) was first explored, he said. At that time, mammary artery bypass grafts were available for operations on vessels toward the front of the heart, and catheter-based procedures were coming into play to treat vessels other than the left anterior descending artery.
According to CTS.net, "the first coronary hybrid procedures were reported by Angelini and coworkers in the Lancet" in 1996, but the approach fell out of favor in part because of the technical demands of MIDCAB.
The article also states that very few institutions "installed operating rooms with coronary angiography systems that allowed simultaneous operations, even though it was envisioned that such cath-lab operating rooms would be one solution to the problem" of bringing this approach further along.
Byrne addressed this dilemma simply, saying that "[w]e need to either bring the cath lab into the operating room or vice versa," and he said he preferred the latter because it would more readily allow for routine intra-operative imaging.
"Angiography is the gold standard in coronary evaluation," he said, but conventional ORs do not typically have the capacity to perform angiograms in the hybrid lab. However, in a hybrid OR, the surgeon "can obtain imaging every time."
Byrne said that the typical heart surgeon performs about 200 surgeries each year, with an average of three grafts apiece. Each graft requires about 50 "critical maneuvers," or up to 30,000 of such maneuvers a year, adding that no surgeon gets it right 100% of the time.
"Surgeons are like professional golfers: most are superb surgeons . . . but every once in a while, even Tiger Woods misses the fairway," he said.
Byrne cited a randomized, double-blind study published in the Journal of the American Medical Association in 2005, estimating that 30% of CABG patients who received saphenous vein grafts experienced a failure of the graft in the first year. The problems don't stop there.
"One thing is for sure," Byrne said, "patients that come to cardiac surgery are higher risk and more complex than ever, and it's going to get worse." As a result, post-surgical complications won't become less frequent or easy to deal with, either.
Byrne said that most such defects are in the conduit of the graft, to the tune of 61%, and some patients experience post-operative mitral regurgitation.
In April 2005, Byrne's institution opened its hybrid OR/cath lab where surgeons will be able to perform conventional CABG procedures as well as PCIs and angioplasties, and he posed the question of why it took so long for medical science to take more seriously this marriage of techniques and technologies.
"Someone could have done this 20 years ago," he said. All that is required is "the ability to think differently, to consider interventional cardiologists" as colleagues.
"It's not the technique, it's not the space or the money," he said.
In order to change, one must simply realize that "you are on a burning platform, and then form a sufficiently powerful guiding coalition, and communicate the vision thousands of times," Byrne said, adding that "at least some aspects of our specialty, we are like PT 109," the patrol torpedo boat commanded by John F. Kennedy during his tour of duty in World War II.
PT 109 was literally cut in half by the passing of a destroyer of Japan's Imperial Navy. And Byrne likened the split between interventionists and cardiologists to the plight of the survivors of PT 109, who had to abandon the boat.
Byrne rhetorically posed the question of whether the hybrid approach constitutes a disruptive technology.
But he then went on to answer the question: "Its hard to say—only time will tell."
Byrne also said that he would not try to predict what coronary artery surgery will look like in 30 years, but offered one way to see into the future.
"The best way to predict the future is to invent it," he said.