Validation of an Intracycle CT Motion CORrection Algorithm for Diagnostic AccuracY

Hypothesis: Coronary CT angiography (CCTA) employing a novel intracycle motion compensation
algorithm (SnapShot Freeze [SSF]) will be superior to CCTA without an intracycle motion
compensation algorithm ("conventional" CCTA) for diagnostic accuracy and image quality.

Scientific Basis: Preliminary study (Leipsic, Min, Journal of Cardiovascular Computed
Tomography [in press]) of coronary CT angiograms in individuals undergoing pre-procedural
assessment for transcatheter aortic valve replacement (n=36) demonstrate improved image
quality of CCTA using SSF compared to CCTA not using SSF. Importantly, individuals in this
study did not receive heart rate slowing agents (e.g., beta blockers), and diagnostic image
quality was substantially improved. While not statistically powered on a per-patient basis,
per-segment diagnostic accuracy of CCTA using SSF was superior to conventional CCTA. These
results are complementary to those derived from internal testing at GE Healthcare wherein
phantom work has demonstrated improved diagnostic performance using SSF compared to
conventional image acquisitions.

Long-term Goal/Purpose: To demonstrate the incremental utility of SSF for individuals
undergoing CCTA, with expected improvements in image quality and diagnostic accuracy. If
the aims of this study are achieved, the use of SSF for effective temporal resolution
improvement may obviate (or reduce) the need for CT hardware for improved temporal
resolution.

Inclusion Criteria:

1. Consenting adult patients ≥18 years of age;

2. Suspected but without known prior history of CAD

3. Not actively taking heart rate lowering agents at least 48 hours prior to study
(e.g., AV nodal blockers such as beta blockers, calcium channel blockers or digoxin)

4. Glomerular filtration rate >60 ml/min

5. CCTA and ICA within 1 week of each other with no interscan event (e.g., myocardial
infarction or coronary revascularization)

Exclusion Criteria:

1. Incomplete ICA or CCTA;

2. Known CAD (prior myocardial infarction, PCI, CABG)

3. Atrial Fibrillation

4. Abnormal Renal Function (GFR <60 ml/min)

5. Unwilling or unable to give consent

6. Non-cardiac illness with life expectancy <1 year

7. Concomitant participation in another clinical trial in which subject is subject to
investigational drug or device

8. Pregnant women

9. Allergy to iodinated contrast agent

10. Contraindications to nitroglycerin

11. Systolic blood pressure ≤90 mm Hg

12. Contraindications to β blockers or nitroglycerin