Intravascular Ultrasound–Guided Percutaneous Coronary Interventions

Abstract

Coronary angiography falls short in accurately delineating the anatomy of epicardial vessels because it provides only a 2-dimensional visualization of the lumen.1 Moreover, angiographic lesion assessment is impeded in cases of diffuse disease of reference vessels, lesion foreshortening, and eccentricity, and the overlap of several arterial branches, as well. Conversely, intravascular ultrasound—a sound wave–based technology—provides superior spatial resolution of 80 to 150 μm and extends diagnostic information, enabling more precise assessment of lumen and vessel wall dimensions including atheroma burden and vessel remodeling. Article see p 463 Intravascular ultrasound (IVUS) has been proposed for the assessment of lesion severity in cases of intermediate left main and non–left main lesions. In addition, IVUS has been used to guide percutaneous coronary interventions (PCI) by informing the operator of reference vessel dimensions, lesion length, and extent of calcification to plan the procedure. Finally, IVUS has been implemented to optimize stent deployment, and criteria have been developed such as the Multicenter Ultrasound Guided Stent Implantation (MUSIC)2 and Angiography versus IVUS Optimization (AVIO)3 criteria to this effect. During the bare metal stent era, IVUS guidance was reported to reduce the risk of restenosis and repeat revascularization.4 In contrast, the use of IVUS after drug-eluting stent (DES) implantation failed to improve clinical efficacy with IVUS guidance despite larger stent dimensions at the end of the procedure. Notwithstanding, some studies suggested a lower risk of stent thrombosis with IVUS-guided DES implantation owing to the detection of mechanical factors associated with stent thrombosis, including edge dissections, stent malapposition, and stent underexpansion.5 More recently, the propensity score–matched comparison of IVUS guided with angiography-guided PCI of unprotected left main lesions (MAIN-COMPARE)6 reported lower mortality, with IVUS guidance potentially related to a lower risk of sudden death and stent thrombosis. Current American College of Cardiology …