New acquisition method to exclusively enhance the left side of the heart by a small amount of contrast material achieved by multislice computed tomography with 64 data acquisition system

Purpose To exclusively enhance the left side of the heart by a small amount of contrast material (CM) using rapid acquisition of multislice computed tomography (MSCT) with a 64-data acquisition system (DAS). Materials and methods Forty consecutive subjects underwent MSCT (Light Speed VCT, GE) with 0.625 mm slice thickness to evaluate coronary arteries. We first measured transit time, using 8 ml of CM followed by 20 ml saline. Dependent upon transit time, total volume of CM was determined, ranging from 45 to 63 ml. After injection of CM at a rate of 4 ml/s, followed by 47 ml saline at 3.5 ml/s, ECG-gated MSCT scanning was performed. The mean and standard deviation (S.D.) of CT values of the right atrium (RA), right ventricle (RV), left atrium (LA), left ventricle (LV), ascending aorta (Ao) and each coronary artery were measured. Results The mean of the CT values of the RA, RV, LA, LV, Ao, right coronary artery, left main, left anterior descending branch, and left circumflex branch were 225 ± 76, 251 ± 72, 353 ± 55, 355 ± 51, 352 ± 34, 312 ± 65, 296 ± 57, 285 ± 55, and 267 ± 60 HU, respectively. The corresponding S.D.s of the CT values were 39 ± 22, 37 ± 16, 32 ± 7, 31 ± 8 HU, 25 ± 5, 36 ± 15, 31 ± 13, 36 ± 23, and 40 ± 18 HU, respectively. The mean of CT values of the RA and RV were significantly lower than those of the LA, LV, Ao, and each coronary artery (P < 0.01), with excellent S.D.s. We could easily obtain three-dimensional coronary arterial and LV images without artifact of the RA and RV. Conclusions Using 64-DAS MSCT, we successfully obtained exclusive enhancement of the left side of the heart using a small amount of CM.