ABSTRACT
BACKGROUND: Semi-quantitative stenosis assessment by coronary CT angiography only modestly predicts stress-induced myocardial perfusion abnormalities. The performance of quantitative CT angiography (QCTA) for identifying patients with myocardial perfusion defects remains unclear. METHODS: CorE-64 is a multicenter, international study to assess the accuracy of 64-slice QCTA for detecting ≥50% coronary arterial stenoses by quantitative coronary angiography (QCA). Patients referred for cardiac catheterization with suspected or known coronary artery disease were enrolled. Area under the receiver-operating-characteristic curve (AUC) was used to evaluate the diagnostic accuracy of the most severe coronary artery stenosis in a subset of 63 patients assessed by QCTA and QCA for detecting myocardial perfusion abnormalities on exercise or pharmacologic stress SPECT. RESULTS: Diagnostic accuracy of QCTA for identifying patients with myocardial perfusion abnormalities by SPECT revealed an AUC of 0.71, compared to 0.72 by QCA (P = .75). AUC did not improve after excluding studies with fixed myocardial perfusion abnormalities and total coronary arterial occlusions. Optimal stenosis threshold for QCTA was 43% yielding a sensitivity of 0.81 and specificity of 0.50, respectively, compared to 0.75 and 0.69 by QCA at a threshold of 59%. Sensitivity and specificity of QCTA to identify patients with both obstructive lesions and myocardial perfusion defects were 0.94 and 0.77, respectively. CONCLUSIONS: Coronary artery stenosis assessment by QCTA or QCA only modestly predicts the presence and the absence of myocardial perfusion abnormalities by SPECT. Confounding variables affecting the relationship between coronary anatomy and myocardial perfusion likely account for some of the observed discrepancies between coronary angiography and SPECT results.
Subject(s)
Coronary Angiography/methods , Coronary Circulation , Coronary Stenosis/diagnostic imaging , Multidetector Computed Tomography/methods , Aged , Female , Humans , Male , Middle Aged , Tomography, Emission-Computed, Single-PhotonABSTRACT
Due to the growing toolkit of targeted contrast agents, molecular imaging continues to play a prominent role in the clinical care of cancer. Peptide-based imaging approaches are of particular significance due to their favorable pharmacokinetic properties, established manufacturing infrastructure, and documented clinical success in whole-body imaging. A logical extension of molecular imaging with peptides is to improve surgical outcomes in cancer through highly sensitive and specific probes which can be used intraoperatively. Advances in fluorescent imaging have resulted in various peptide labeling strategies with intraoperative indications. In this review, we focused on the evolving design of peptide imaging agents starting with the clinically used somatostatin targeting peptides. We then review the current synthetic approaches used for dual-labeled agent development and offer perspectives on optimal protection schemes that can be used for multimodal probe development.
Subject(s)
Drug Design , Molecular Imaging/methods , Peptides , Whole Body Imaging/methods , Amino Acid Sequence , Animals , Humans , Intraoperative Period , Peptides/chemical synthesis , Peptides/chemistry , Peptides/metabolism , Receptors, Somatostatin/metabolismABSTRACT
It is clear that various imaging modalities have given keen insight into the molecular mechanisms involved in anti-angiogenic treatments. A key to the advancement of anti-angiogenic therapy is not only the discovery of new drugs and treatments, but the analysis of the specific modes of action of these compounds in order to produce the next generation with greater effectiveness. While existing clinical methods incorporate the analysis of serum and urine to measure angiogenic factors, an imaging technique monitoring the effectiveness of anti-angiogenic therapy would be a convenient, noninvasive, cost effective technique to aid in treatment planning and disease management.
