A head-to-head comparison of the coronary calcium score by computed tomography with myocardial perfusion imaging in predicting coronary artery disease

Objectives: The coronary artery calcium (CAC) score has been shown to predict future cardiac events. However the extent to which the added value of a CAC score to the diagnostic performance of myocardial perfusion imaging (MPI) by single photon emission computed tomography (SPECT) is unclear. The purpose of this study is to investigate the correlation between CAC score and SPECT in patients with suspected coronary artery disease. Methods: A retrospective review of the CAC scores by use of the Agatston calcium scoring method and cardiac SPECT diagnostic reports was conducted in 48 patients, who underwent both coronary computed tomography (CT) and SPECT examinations due to suspected coronary artery disease. A Pearson correlation test was used to determine the relation between CAC scores and MPI-SPECT assessments with regard to the evaluation of the extent of disease. Results: Forty-seven percent of the patients had CAC scores more than 100, while 42% of these patients demonstrated abnormal, or probably abnormal, MPI-SPECT. Of the 23% of patients with a zero CAC score, only 7% had normal MPI-SPECT findings. No significant correlation was found between the CAC scores and MPISPECT assessments (r value ranged from 0.012 to 0.080), regardless of the degree of coronary calcification. Conclusions: There is a lack of correlation between the CAC scores and the MPI-SPECT findings in the assessment of the extent of coronary artery disease. CAC scores and MPI-SPECT should be considered complementary approaches in the evaluation of patients with suspected coronary artery disease

CT angiography in the diagnosis of cardiovascular disease: A transformation in cardiovascular CT practice.

Computed tomography (CT) angiography represents the most important technical development in CT imaging and it has challenged invasive angiography in the diagnostic evaluation of cardiovascular abnormalities. Over the last decades, technological evolution in CT imaging has enabled CT angiography to become a first-line imaging modality in the diagnosis of cardiovascular disease. This review provides an overview of the diagnostic applications of CT angiography in cardiovascular disease, with a focus on selected clinical challenges in some common cardiovascular abnormalities, which include abdominal aortic aneurysm, aortic dissection, pulmonary embolism and coronary artery disease. An evidence-based review is conducted to demonstrate how CT angiography has changed our approach in the diagnosis and management of cardiovascular disease. Radiation dose reduction strategies are also discussed to show how CT angiography can be performed in a low-dose protocol in the current clinical practice

Double low-dose computed tomography pulmonary angiography in the diagnosis of pulmonary embolism

The purpose of this study is to investigate the feasibility of double low-dose (low radiation and low contrast medium doses) computed tomography pulmonary angiography (CTPA) in the diagnosis of pulmonary embolism. This retrospective study involved analysis of 59 patients undergoing 64- and 128-slice CTPA examinations which were scanned with a pitch of 0.9 and 100 and 120 kVp, respectively, while flash mode of CTPA was done with a pitch of 3.2 and 120 kVp. There were no significant differences in image quality assessment between the low kVp and standard kVp or high-pitch CTPA protocols (p=0.181-0.186). The mean effective dose for the 100 kVp protocol was significantly lower than that for the120 kVp and the flash mode protocols (p<0.001). The contrast medium was between 35-45 ml for the 100 and 120 kVp protocols, and 20-30 ml for the 120 kVp flash mode protocol. Double low-dose CT pulmonary angiography is feasible for detection of pulmonary embolism with acquisition of diagnostic images

CEACAM1 inhibits Toll-like receptor 2-triggered antibacterial responses of human pulmonary epithelial cells

Although Moraxella catarrhalis and Neisseria meningitidis are important human pathogens, they often colonize the human respiratory tract without causing overt clinical symptoms. Both pathogens express structurally unrelated proteins that share the ability to stimulate the adhesion molecule CEACAM1 expressed on human cells. Here we demonstrate that the interaction of CEACAM1 with ubiquitous surface protein A1 expressed on M. catarrhalis or with opacity-associated proteins on N. meningitidis resulted in reduced Toll-like receptor 2-initiated transcription factor NF-kappa B-dependent inflammatory responses of primary pulmonary epithelial cells. These inhibitory effects were mediated by tyrosine phosphorylation of the immunoreceptor tyrosine-based inhibitory motif of CEACAM1 and by recruitment of the phosphatase SHP-1, which negatively regulated Toll-like receptor 2-dependent activation of the phosphatidylinositol 3-OH kinase-Akt kinase pathway. Our results identify a CEACAM1-dependent immune-evasion strategy