ABSTRACT
Significant problems were encountered with firstgeneration balloon-expandable stents, which tended to be bulky and difficult to deliver, and either had to be hand crimped onto a balloon or were unreliably adherent to their delivery catheters. In these circumstances, balloon predilatation was considered necessary and important to permit easy, safe passage of the stent delivery system across the stenosis. With secondgeneration stents, many of these problems have been overcome through improvements in crossing profile and stent bonding.3,4 The crossing profile of the current-generation stents, at less than 1.25 mm, is significantly lower than that of the first-generation Palmaz-Schatz delivery system (1.65 mm). Interventional cardiologists have since striven to identify ways of reducing both the complexity and costs to the patients, and healthcare providers, of coronary interventions.5,6 In addition, particularly with complex cases, there has been a need to reduce exposure time to radiation and the amount of contrast agent used. One such approach to enable this is direct stenting, which refers to the technique of coronary stent implantation without initial balloon predilatation of the coronary lesion.7,8
Direct stenting has been shown in some studies to have an improved or equivalent clini-
cal outcome compared to the pre-dilatation strategy, often with reduced procedural costs.4,9
In part, this may be due to the observation that aggressive pre-dilatation is more commonly associated with extensive dissection which is reduced by directly sealing off any dissection plane, and reducing the associated exposure of platelet-activating and cell proliferative substances. Other potential advantages of direct stenting are reductions in ischemia, equipment cost, radiation dose, procedural time, and radiographic contrast use. Preliminary observations suggest that the strategy of direct stenting is applicable with modern stents in up to about 40-60% of all coronary interventions.10,11 With increasing safety and economic data being gathered by randomized trials and prospective registries, this may become the method of choice in eligible lesions.
