BALLOON ANGIOPLASTY "SHOULD BE SELECTED FOR MOST CORONARY LESIONS"

BALLOON ANGIOPLASTY "SHOULD BE SELECTED FOR MOST CORONARY LESIONS" based on results of the Coronary Angioplasty versus Excisional Atherectomy Trial (CAVEAT) and the Canadian Coronary Atherectomy Trial (CCAT), John Bittl, MD, Brigham and Women's Hospital, Boston, concludes in an editorial published in the July 22 New England Journal of Medicine. Citing the results from the two studies published in the same NEJM issue, Bittl says that balloon angioplasty is preferable to atherectomy in most cases because it is "safer and more cost effective." Stenoses for which atherectomy may be preferable, however, include those "in saphenous-vein bypass grafts, which are difficult to treat with balloon angioplasty," and those in "the coronary ostia, which are difficult to dilate with balloon angioplasty," Bittl says. Atherectomy can also be used "as a salvage procedure" immediately after angioplasty "if incomplete dilation is achieved with balloon angioplasty in the absence of a large coronary artery dissection." Atherectomy may also be preferable in highly eccentric lesions, Bittl says. Preliminary results of both the CAVEAT trial, by Eric Topol, MD, Cleveland Clinic Foundation, et al., and the CCAT trial, by Allan Adelman, MD, Mount Sinai Hospital, Toronto, et al., were presented last November at the American Heart Association annual meeting in New Orleans ("The Gray Sheet" Nov. 23, 1992, p. 10). In the CAVEAT randomized clinical study, which included 1,012 patients at 35 sites in the U.S. and Europe, excisional coronary atherectomy was performed using the DCA (directional coronary atherectomy) device manufactured by Lilly's Devices for Vascular Intervention, Inc. subsidiary. Despite a higher procedural angiographic success rate for atherectomy compared to angioplasty (89% vs. 80%, p<0.001), a larger immediate increase in luminal diameter (1.05 vs. 0.86mm, p<0.001) and a "small reduction in angiographic restenosis" rate at six months (50% vs. 57%, p=0.06), the researchers found that atherectomy leads to "a higher rate of early complications, increased cost and no apparent clinical benefit after six months of follow-up." Atherectomy patients were more likely to have in-hospital abrupt vessel closure or myocardial infarction, or require an emergency coronary artery bypass graft (CABG). The overall early complication rate was 11% for atherectomy and 5% for angioplasty (p<0.001). Total in-hospital costs were also higher for atherectomy ($17,489 vs. $15,263). Within six months, "the probability of death or myocardial infarction" was 8.6% in the atherectomy group and 4.6% for the angioplasty group (p=0.007). The CAVEAT researchers concluded that balloon angioplasty is "the preferred approach overall unless and until techniques of atherectomy can be improved or until convincing, reproducible findings indicate that certain subgroups will benefit from atherectomy from a clinical as well as an angiographic standpoint." The CCAT study compared directional atherectomy with balloon angioplasty for lesions of the left anterior descending coronary artery. The 274-patient randomized trial found that "as compared with angioplasty, atherectomy did not result in better late angiographic or clinical outcomes in patients with lesions of the proximal left anterior descending coronary artery." Like the CAVEAT study, CCAT found a higher procedural success rate for atherectomy as compared to angioplasty (94% vs. 88%, p=0.061), although researchers found no significant difference in in-hospital complications (5% vs. 6%) and a higher rate of restenosis at followup (performed at a median of 5.9 months for most patients) for atherectomy procedures (46% vs. 43%, p=0.71). Higher initial gains in luminal diameter with atherectomy were offset by greater losses during the followup period, and "there was no significant difference between groups in the minimal luminal diameter at followup." Adelman et al. conclude that "the role of atherectomy in percutaneous coronary revascularization remains to be fully defined." In his editorial, Bittl praised both studies for their "careful analysis," adding that "the results provide a consistent message about the similar clinical outcomes after directional atherectomy and balloon angioplasty with the methods employed."