Near-infrared spectroscopy-intravascular ultrasound to improve assessment of coronary artery disease severity in patients referred for transcatheter aortic valve implantation (The IMPACTavi registry): Design and rationale.

Background: Transcatheter aortic valve implantation (TAVI) was established as a standard treatment for high-operative risk patients with severe aortic stenosis (AS). Although coronary artery disease (CAD) often coexists with AS, clinical and angiographic evaluations of stenosis severity are unreliable in this specific setting. To provide precise risk stratification of coronary lesions, combined near-infrared spectroscopy and intravascular ultrasound (NIRS-IVUS) was developed to integrate morphological and molecular information on plaque composition.