Subject recruitment was slow, so enrollment has been closed.

The purpose of this study is to compare different methods of looking at atherosclerotic plaques in heart arteries. Identifying the characteristics of these plaques noninvasively would be very valuable. This study is looking at a new CT scanner (DSCT) to noninvasively image these plaques compared to invasive ultrasound (the current standard).

The primary objectives of this study are:

1. To compare with contrast angiography, the ability of DSCT to detect and quantify coronary artery stenoses.
2. To compare with gray-scale IVUS, the ability of DSCT to quantify plaque cross-sectional diameter & area measurements & plaque volume.
3. To evaluate the ability of DSCT to assess plaque morphology and quantify plaque components as compared to gray-scale and IB-IVUS.
4. To evaluate the ability of DSCT to identify & measure lesion remodeling compared to gray-scale IVUS.
5. To determine if pre-PCI evaluation of coronary plaque morphology by IB-IVUS can a) predict procedural success as assessed by adequate stent strut apposition and expansion and b) peri-procedural myocardial necrosis as measured by biomarker elevation.

Inclusion Criteria:

• Males or non-pregnant females
• > / = 18 years of age
• Scheduled for coronary angiography

Exclusion Criteria:

• Acute ST-elevation myocardial infarction within last 72 hours
• Current congestive heart failure
• Current cardiogenic shock
• Unstable clinical condition
• Known cardiomyopathy (EF < 30%)
• Creatinine >1.5 mg/dL
• Definite allergy to iodinated contrast media
• Current participation in an investigational drug or device research study
• HR > 65 and contraindications to the administration of beta blockers

Exclusion criteria assessed during catheterization procedure

• PCI of native coronary vessel not performed
• Left main stenosis > 50%
• Any vessel contraindicated for IVUS imaging
• Any lesion contraindicated for IVUS imaging
• Inability to pass IVUS catheter
• PCI of bifurcation lesion

Total number of subjects at risk=4 since 20 subjects were screen failures and did not have any study imaging.

Study terminated after imaging 4 subjects due to slow enrollment. Results will not be analyzed.