In selected patients, Coronary CT Angiography (CCTA) will be performed after the initial procedure to open the artery within 40 days. CCTA images will be evaluated for plaque characteristics, and correlated with the invasive findings.Fractional flow reserve via computed tomography (FFRCT), a non-invasive computed tomography method of measuring blood flow in the blocked arteries; will also be determined and correlated with invasive FFR.