DALLAS — Newly updated joint national percutaneous coronary intervention guidelines have some cardiologists seeing red.
The major point of contention regarding the first update of the guidelines since 2001 concerns the use of PCI in centers without on-site surgical backup.
“Of all the areas we covered in the guidelines, this is the area that's going to raise the most controversy and interest,” William W. O'Neill, M.D., predicted at a press conference announcing release of the guidelines during the annual scientific sessions of the American Heart Association.
As in the 2001 guidelines, the new version nixes elective PCI at centers without on-site surgical backup. Primary PCI for patients with ST-segment elevation MI, when done in experienced centers lacking on-site surgical backup, gets a class IIb recommendation—the weakest possible endorsement—meaning there is divergent expert opinion and “less well established” supporting evidence.
Sidney C. Smith Jr., M.D., who headed the guideline writing committee, said the group was persuaded to retain the recommendation against elective PCI in the absence of on-site surgical backup chiefly by a large study of the Medicare database that showed worse outcomes in such settings.
“That carried the weight,” according to Dr. Smith, professor of medicine and director of the Center for Cardiovascular Science and Medicine at the University of North Carolina, Chapel Hill.
“There is no access-to-care issue in the U.S. about angioplasty. We have minimal waiting times,” added Dr. O'Neill, corporate chairman of cardiology for the William Beaumont Hospital System, Royal Oak, Mich. “There really is no proof that we could see right now that doing these procedures [without on-site backup] enhances the value to the patient or makes it safer—if anything, it could make it worse.”
But Thomas P. Wharton Jr., M.D., said in an interview that since the 2001 guidelines there have been 15 new studies of PCI at hospitals without on-site backup; the committee failed to cite or apparently consider 12 of them, all of which were positive, a deficiency he termed “not fathomable.” Collectively these large studies boost primary PCI without on-site backup into a legitimate class IIa procedure and make a strong case for elective PCI as a class IIb recommendation, he said.
Among these studies was one presented at the same AHA meeting that involved more than 660,000 consecutive PCIs included in the American College of Cardiology's rigorous prospective National Cardiovascular Data Registry. In-hospital mortality in the 6,530 patients who underwent primary or nonemergent PCI without on-site backup was comparable with that in patients who had PCI with on-site backup. The guidelines task force was provided with the results of this and the other studies, said Dr. Wharton of Exeter (N.H.) Hospital.
“PCI is underutilized in acute MI and other high-risk acute coronary syndromes, most of which present to hospitals without PCI—a definite access problem.” Providing PCI at such hospitals will improve access and thereby could lower mortality rates. This far outweighs the downside risk of 1–2 patients per 1,000 experiencing a PCI complication requiring emergency bypass surgery within 2 hours, which with good transfer planning in place can be accomplished off-site, he added.
“Performance of PCI at qualified hospitals with off-site surgical backup is a growing grassroots movement. It's being done in 36 states. More states are changing their regulations to allow it. The ACC should recognize and help guide this growing movement,” Dr. Wharton said.
Among the other key recommendations in the new guidelines:
▸ Volume requirements. As in 2001, the 2005 guidelines recommend that elective PCI be performed by physicians who do at least 75 PCI procedures per year, and in centers where more than 400 per year are done. But the institutional volume requirement may be headed for the scrap heap. In another report from the ACC National Cardiovascular Data Registry presented at the AHA meeting, William S. Weintraub, M.D., and his coinvestigators found no evidence of a relationship between institutional PCI volume and in-hospital mortality in a series of nearly 668,000 patients who underwent PCI in the contemporary era of improved stents and antiplatelet regimens.
“The task force is aware of our data,” Dr. Weintraub said in an interview. “I think before they change their recommendations, they're going to want to see our final results in print. The next version of the guidelines will probably get away from the institutional volume requirement,” predicted Dr. Weintraub, director of outcomes for the Christiana Care Health System, Newark, Del.
▸ Left main coronary artery disease—a new PCI target. Considered the exclusive domain of surgeons since the inception of bypass surgery, left main disease is for the first time deemed reasonably addressed via PCI provided the patient is a poor surgical candidate.