Single-crystal-to-single-crystal (SCSC) reactions are rare for organic solids. We describe the first example of an SCSC [2+2] photodimerization that is mediated by halogen bonding.

BackgroundCoronary computed tomography angiography (CCTA) has emerged as a helpful tool in the evaluation of patients with chest pain and suspected coronary artery disease (CAD). The study objective was to evaluate the clinical application of CCTA for assessment of patients presenting with chest pain at a large single urban tertiary health care center located in the US.MethodsA retrospective review of observational data from center was conducted. The study sample included outpatients aged 18 years or older who underwent CCTA during January 2018 through February 2020.ResultsThere were 158 patients in the study, with sixty-two percent having stress testing within 6-months prior to CCTA. Fifty-five percent of these patients had abnormal stress test findings but demonstrated no CAD on CCTA. Among the patients with normal stress tests, 24.4% demonstrated CAD on CCTA. Twenty-five patients underwent invasive coronary angiography (ICA) within the 6-months following CCTA. For these patients, the positive predictive value of CCTA was 91.3% (95% CI: 72.0%, 99.0%) and negative predictive value was 100.0% (95% CI: 15.8%, 100.0%) when compared to ICA results. In addition, CCTA demonstrated myocardial bridging in 10.0% and an anomalous coronary vessel in 8.8% of patients.ConclusionsThis study revealed that CCTA is being used as a diagnostic test in patients presenting with chest pain at the study center. Among patients with prior stress testing, these results were at times potentially inconsistent with the findings from the CCTA. In addition, the CCTA was able to identify variants in anatomical structures.