ECG-less Coronary Computed Tomography Angiography in the Management of Patients Presenting With High-troponin Chest Pain

Scanning with a Revolution Apex Elite system (GE Healthcare, WI, USA), using hyperdrive pulmonary CT angiography (523mm/s with 0.28s/rotation gantry speed). Images will be acquired using the ECG-less Cardiac software (GE Healthcare, WI, USA), without the need for patient-attached ECG leads. The system uses a wide detector coverage of 160mm to provide full heart coverage and a fast gantry speed of 0.23 seconds per rotation to perform imaging in a single cardiac cycle. An estimation of the heart rhythm must be provided, based on the heart rhythm the scanner simulates an ECG signal. This simulated ECG signal provides virtual gating of the scan. Advanced software tools including SmartPhase (automated phase selection) and SnapShot Freeze 2 (optimized volume registration) will be used. After a short delay of 5-12 sec, allowing contrast to pass from the pulmonary circulation into the aorta and coronary arteries, a coronary CT angiography will be performed using the same contrast bolus.