Editorial Comment Interventional Cardiology The Decade Ahead

B alloon angioplasty, arguably cardiology's most important advance of the decade past, now suffers from what we will call the 5-45-50 problem: 5 % acute closure, ' 45 % restenosis,2,3 and 50 % unsuitable coronary anatomy. We are now be-ginning to see the first publications describing multi-center experiences with three types of devices-atherectomy, lasers, and stents-originally designed to reduce the 45 % restenosis rate. None have thus far clearly demonstrated an effect on either this problem or the acute complication rate, but the wonderful irony is that they apparently will have an important impact on the 50 % problem. Thus, while none of the devices may replace balloon angioplasty, it now seems likely that several will occupy specific niches in interventional cardiology. As reported in this issue of Circulation, Ellis et al relate procedural success with directional atherectomy to stenosis location and mor-phology,4 thus establishing the first clear niche for one of the devices. See p 644 Only in the last year has the concept of niches emerged. In retrospect, the landmark article for this idea may well become the report of the Multivessel Angioplasty Prognosis Study Group, which estab-lished that stenosis morphology has a major impact on both short- and long-term outcomes after balloon angioplasty.5 Using the American College of Cardi-ology/American Heart Association Task Force clas-sification criteria,6 they reported a 92 % success rate and a 2 % complication rate for type A (noncomplex, short) stenoses. In contrast, type C (complex, long) lesions had only a 61 % success rate and 21 % of patients had major complications. Some of these more difficult lesions, which clearly present a poten-tial contraindication to balloon angioplasty, seem particularly well suited for therapy with the new devices. The opinions expressed in this editorial comment are not neces-sarily those of the editors or of the American Heart Association