This is a prospective single center clinical study designed to evaluate the long term struts coverage and vessel wall response (abnormal intraluminal defects, strut malapposition, vessel espansions) to the PROMUS™ Everolimus Eluting Stent compared to PROMUS ELEMENT ™ Everolimus Eluting Stent implanted for the treatment of stenosis in native coronaries. The difference between the two stents is in the stent platform made of a novel alloy of chromium-platinum with low strut thickness and stent crossing profile (0.042" \[1.062 mm\]) for PROMUS ELEMENT ™ Everolimus Eluting Stent. To investigate the completeness of struts coverage as well as the proportion of malapposed struts and the neointima characteristics, high resolution (\~ 10 µ axial) intracoronary Optical Coherence Tomography (OCT) and intravascular coronary ultrasound (IVUS) will be used. The study will be carried out at Ospedali Riuniti di Bergamo, Italy with a target enrollment of consecutive 21 patients for each group receiving one or two Everolimus Eluting stents. All patients enrolled in the study will be followed to 12 months post stent placement.

PLATFORM TO BE USED PROMUS™ everolimus eluting stent. Stent sizes: 2.5 to 3.5 mm, 12 - 15 - 20 - 23 - 28 mm in lengths (according to product specifications).

PROMUS ELEMENT ™ Everolimus Eluting Stent. Stent sizes: 2.5 to 3.5 mm, 12 - 15 -20 - 23 - 28 mm in lengths (according to product specifications).

Patients presenting with a coronary artery lesion who are considered candidates for percutaneous coronary intervention and stent placement are eligible for the OCTEVEREST (Optical Coherence Tomography for EVERolimus Eluting STent)trial. Patients may have a second study lesion that can be treated with a second PROMUS™ Stent or PROMUS ELEMENT ™ Everolimus Eluting Stent.

Patients who do not meet all inclusion/exclusion criteria will not be enrolled or followed in the study. All patients who are candidates for the OCTEVEREST trial and undergo placement of the device must be consented prior to any data collection by a member of the institution's research team. All patients enrolled will be evaluated according to this protocol, regardless of sequence of treatment that ensues. More than one study lesion in different epicardial vessels may be treated in the same stage procedure. Actual study enrollment occurs following successful pre-dilatation of the study vessel, when the study device is introduced into the body. The target lesion must be able to be covered with a single stent. For diffuse lesions the total lesion length will be measured from the proximal shoulder of the most proximal lesion to the distal shoulder of the most distal lesion and should not exceed 24 mm. At 6 month follow-up, the entire stented region will be used to determine the mean lumen diameter and the percent diameter stenosis.

Optical coherence tomography (OCT) will be performed baseline and at 6 month follow up. Study site is requested to use the same OCT equipment for both procedures. The OCT procedure will be conducted according to Optical Coherence Tomography as specified by the Protocol. Optical Coherence Tomography images will be acquired at 15-30 frames per second (500 angular pixels x 250 radial pixels), from a 0.006" micro-optic core, 0.014" image wire, displayed with an inverse gray-scale lookup table, and digitally archived. The optical source used in this study has a center wavelength of 1310 nm and a bandwidth of 70 nm, providing an axial resolution of (10-12 μm in tissue with a tissue penetration of 2 mm). The transverse resolution, determined by the spot size of the sample arm beam, is 25 μm. OCT images will be analyzed by an independent Corelab (Cardialysis, Cleveland) expert in high resolution OCT analysis. An automatic analysis with novel dedicated software will be used for quantitative assessment. Interactive revision of contour appropriateness will be performed by experienced readers. In a blind fashion 10% of all sections will be re-evaluated to estimate the measurement variability (k value). The existence of malapposition will be assessed.

Angiography Angiography will be performed at baseline prior to stent placement, after stent placement, and at 6 month follow up. The Angiography procedure will be conducted according to Angiographic Core Laboratory procedure .A baseline angiography of the involved vessel will be performed in at least two near orthogonal views. Visual angiographic assessment will be used to determine if the lesion meets angiographic entry criteria. The study lesion must be free of foreshortening or vessel overlap. If angiography demonstrates that the target lesion meets study eligibility criteria, then the patient may be enrolled in the study.

Intravascular Ultrasound IVUS will be performed at the time of index procedure and at 6 month follow up. IVUS will initially be performed after successful, uncomplicated stent implantation (diameter stenosis \<10%, TIMI-3 flow). Study site IS requested to use the same IVUS equipment for both procedures. IVUS will be performed on all patients according to IVUS Core. Laboratory Acquisition Protocol. Imaging will be performed with a 40 MHz Atlantis catheter (Boston Scientific), after 50- 200 mcg of intracoronary nitroglycerin. Automated motorized pullback at 0.5 mm/sec will utilized during all IVUS runs (Hi-Lab Boston Scientific). Imaging will include the edges at least 5 mm proximal and distal to the stent. The transducer will be advanced at least 10 mm distal to the distal edge of the stent(s), and a continuous, uninterrupted imaging run performed to a point at least 10mm proximal to the proximal edge of the stent(s). All IVUS studies will be archived for subsequent CoreLab analysis in DICOM format. IVUS analysis will include measurements of external elastic membrane (EEM), stent, and lumen cross-sectional areas and volumes according to the Standards for the Acquisition, Measurement, and Reporting of Intravascular Ultrasound Studies. In addition, qualitative analysis (incomplete apposition, dissections) will also be performed according to the same standards document.