Intravascular ultrasound guided percutaneous coronary intervention: a practical approach

Percutaneous coronary intervention (PCI) with stent implantation has become the predominant revascularization therapy for coronary artery disease. However, stent thrombosis and instent restenosis remain 2 major complications. Limitations of stand-alone angiographic guidance play a significant role in the pathogenesis of these complications. Intravascular ultrasound (IVUS) guidance intuitively offers the best chance of optimizing the acute procedural outcomes, which translates to lower incidences of thrombosis and restenosis. This article aims to provide a practical approach on preintervention and postintervention lesion assessment by IVUS. Emphases of this article are on correct interpretation and application of the various vascular parameters obtained during IVUS imaging. Although consensus on some areas is lacking, the most commonly agreed IVUS concepts and criteria are presented. Limitations of the IVUS-guided PCI on routine clinical practice are also addressed. A summary of the randomized study comparing IVUS- versus angiographic-guided PCI, together with a critical appraisal of the data, are also presented. The roles of IVUS in PCI are likely to undergo revolutionary change in the era of plaque characterization and drug-eluting stents.