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In the field of cardiovascular surgery, cardiac computed tomography (CT) has served an important role in association with the improvement of the spatial and temporal resolution. Because CT angiography (CTA) provides more available information than plain CT, CTA has been increasingly used to access the coronary arteries and graft patency after coronary artery bypass grafting (CABG). Recently, minimally invasive cardiac surgeries, including CABG with left mini-thoracotomy and mitral valve surgery with right mini-thoracotomy, are revived, which requires preoperative CTA to make a strategy of incision placement on the basis of anatomical relationship between the target structure of the heart and the thorax. In Japan, transcatheter aortic valve implantation (TAVI) was approved in the late 2013, and is expected to be widely performed in the future. CTA is extremely useful for TAVI patients to determine the choice of the valve size and the surgical approach. CT provides many other valuable findings to us, but if we cannot fully leverage it in the daily cardiovascular surgery, its value is decreased. We have to acquire enough skill to maximize the performance of CT in the practical clinical setting.

Objective: The purpose of this study was to compare estimates of calcified plaque volume in the carotid arteries based on contrast-enhanced dual-energy CT angiograms with volume estimates based on native CT scans., Conclusion: Detection of hard plaque in the carotid arteries with dual-energy CT angiography was successful in all patients. Estimates of calcified plaque volume based on dual-energy CT angiograms correlated well with those based on native single-energy CT scans but at a lower attenuation threshold (130 HU as opposed to 180 HU) were underestimates compared with those on the native CT scans.

Rationale and Objectives: To establish the utility of multidetector computed tomography (CT) angiography using dual-head power injector in the diagnosis of aortic diseases., Methods: In a prospective study, 151 patients with aortic diseases were examined by four-detector CT. Scanning was performed using bolus tracking technique. In all patients nonionic contrast was injected at the rate of 1.5 mL/sec. One hundred one patients were examined with dual-head power injector using 0.6 mL/kg contrast flushed by 30 mL of saline solution (group D). Fifty patients were examined with single-head power injector using 1.0 mL/kg contrast only (group S). We evaluated CT values at descending aorta, upper abdominal aorta, abdominal aortic bifurcation, and bilateral common femoral arteries., Results: There were no statistically significant difference of CT values at descending aorta, upper abdominal aorta, abdominal aortic bifurcation, and right common femoral artery. At left common femoral artery, CT values in group D were higher than those in group S with statistically difference (P < .05). In group D, about 40% dose reduction was achieved without reducing image qualities., Conclusion: Multidetector CT angiography using dual-head power injector was valuable for the contrast dose reduction of aortic diseases.

Objectives: The purpose of this study was to determine whether high-intensity carotid plaques visualized by a noncontrast T1-weighted imaging technique, magnetization-prepared rapid acquisition with gradient echo (MPRAGE), predict future coronary events in patients with clinically stable coronary artery disease (CAD). Background: Coronary plaque vulnerability to rupture can be assessed by examining for the presence of atherosclerosis and measuring intima media thickness (IMT) in surrogate vessels such as the carotid arteries. We previously showed that MPRAGE successfully identifies vulnerable carotid plaques as high-intensity signals. It remains unclear, however, if the presence of carotid high-intensity plaques (HIP) is associated with an increased risk of coronary events. Methods: We examined the signal intensity of carotid plaques in 217 patients with clinically stable CAD using MPRAGE with magnetic resonance imaging and measured IMT with ultrasonography. A carotid HIP was defined as a signal >200% that of the adjacent muscle. All patients were divided into 2 groups according to the presence or absence of HIP, namely, the HIP group (n = 116) and the non-HIP group (n = 101), and were followed up for as long as 72 months. Results: The presence of HIP was significantly associated with cardiac events compared to the non-HIP group (log-rank p < 0.0001). Furthermore, multivariate Cox regression analysis identified the presence of HIP as the strongest independent predictor of cardiac events (hazard ratio: 3.15; 95% confidence interval: 1.93 to 5.58, p < 0.0001) compared with IMT (hazard ratio: 1.62, 95% confidence interval: 0.97 to 2.44, p = 0.055) and other coronary risk factors. Conclusions: Characterization of carotid plaques using magnetic resonance imaging with MPRAGE provides more clinically relevant information for the risk assessment of CAD patients than IMT. [Copyright &y& Elsevier]