Implante de stent guiado por ultrassom intracoronariano: há mesmo benefício?

Abstract

Dear Editor,We would like to congratulate the authors of the study: "Intracoronary ultrasound-guided stenting improves outcomes: a meta-analysis of randomized trials" 1 and make the following comments:1. There is significant heterogeneity among the metaanalysis studies, which includes both studies with provisional stenting technique, now in disuse, as well as a study with drug-eluting stent. Three studies excluded patients with long lesions and one of them did not use IVUS for lesion analysis prior to stent implantation.2. Although there was no significant reduction in major cardiovascular events (MACE) and myocardial infarction, the number of deaths was higher in the intervention group guided by IVUS. Thus, there is an interpretation bias by the authors, who suggest that "with more studies and a larger number of patients, IVUS-guided stenting can significantly reduce MACE cases," when in fact the number of deaths could also increase.3. The authors conclude on the benefit of IVUS, based analysis of surrogate outcomes: angiographic restenosis and target vessel revascularization, for which blinding is difficult. Only 62% of the studies reported blinding of outcome examiners. The use of surrogate outcomes should be viewed with caution, as it does not always relate to the clinical events of interest 2 .We point out the existence of publication bias in this meta-analysis, a hypothesis reinforced by applying the test of Egger 3 to the data on restenosis (p = 0.037) and MACE (p = 0.023). Considering the figures presented by the authors, it is clear that the smaller studies had "more positive" results and the "trim and fill" 4 test was also positive in our analysis.Thus, we believe that the main conclusion of the study is the absence of evidence of clinical benefit from the use of IVUS to guide stent implantation.Conclusions based on meta-analyses of surrogate endpoints, especially when there is heterogeneity of the studies and suspected publication bias should be assessed with caution.