Between one day and one week after the invasive catheterization patients will return for a research related non-invasive coronary Cat scan. A coronary Cat scan will be repeated at 24 months (2 years) to assess any of the blockages of indeterminate severity that were identified during your initial invasive cardiac catheterization. Upon arrival for Cat scan a nurse will ask the patient a few questions, insert a small tube in one of the patients arm veins. Blood will be drawn from the small tub and kidney function will be assessed. All Cat scans will be completed under Beaumont Hospital Institutional guidelines for coronary Cat scans. If significant blockages are identified, the patient may be notified to complete additional testing, which may include a stress test or a coronary angiogram. If other non-cardiac incidental findings are noted that require additional clinical or imaging follow up, the patient and the primary care physician will be notified.