 2. Rest coronary arterial imaging Rest perfusion and coronary arterial imaging will be performed during a 4-5 mlsec intravenous iodinated contrast ISOVUE-370 infusion. The rest CTA-dynamic CTP images will be started using a test bolus acquisition and accurate quantification of optimum timing for dynamic CTP and boost CTA acquisition and will continue for 20-30 sec using a ECG triggering method to allow acquiring the images only within 70-80 of the R-R interval, but not continuously. The parameters for the dynamic CTP image acquisition are the followings: For the heart rate of 60 bpm the tube voltage will be 80 kV and the tube current will be 100mA. Other parameters are: gantry rotation0.275, range120mm. The CTA and static CTP imaging will be performed as a boost scan during the dynamic CTP with the same tube voltage 80kV but the tube current of 600mA within 70-80 of R-R interval. The boost timing will be quantified from test bolus acquisition. The average radiation dose for rest CTA and rest dynamic and static CTP acquisition is 3.69mSv. 