Computed tomography myocardial perfusion vs (15)O-water positron emission tomography and fractional flow reserve

Objectives: Computed tomography (CT) can perform comprehensive cardiac imaging. We compared CT coronary angiography (CTCA) and CT myocardial perfusion (CTP) with ¹⁵O-water positron emission tomography (PET) and invasive coronary angiography (ICA) with fractional flow reserve (FFR). Methods: 51 patients (63 (61–65) years, 80 % male) with known/suspected coronary artery disease (CAD) underwent 320-multidetector CTCA followed by “snapshot” adenosine stress CTP. Of these 22 underwent PET and 47 ICA/FFR. Obstructive CAD was defined as CTCA stenosis >50 % and CTP hypoperfusion, ICA stenosis >70 % or FFR <0.80. Results: PET hyperaemic myocardial blood flow (MBF) was lower in obstructive than non-obstructive territories defined by ICA/FFR (1.76 (1.32–2.20) vs 3.11 (2.44–3.79) mL/(g/min), P < 0.001) and CTCA/CTP (1.76 (1.32–2.20) vs 3.12 (2.44–3.79) mL/(g/min), P < 0.001). Baseline and hyperaemic CT attenuation density was lower in obstructive than non-obstructive territories (73 (71–76) vs 86 (84–88) HU, P < 0.001 and 101 (96–106) vs 111 (107–114) HU, P 0.001). PET hyperaemic MBF corrected for rate pressure product correlated with CT attenuation density (r = 0.579, P < 0.001). There was excellent per-patient sensitivity (96 %), specificity (85 %), negative predictive value (90 %) and positive predictive value (94 %) for CTCA/CTP vs ICA/FFR. Conclusion: CT myocardial attenuation density correlates with ¹⁵O-water PET MBF. CTCA and CTP can accurately identify obstructive CAD. Key Points: •CT myocardial perfusion can aid the assessment of suspected coronary artery disease. • CT attenuation density from “snapshot” imaging is a marker of myocardial perfusion. • CT myocardial attenuation density correlates with ¹⁵O-water PET myocardial blood flow. • CT attenuation density is lower in obstructive territories defined by invasive angiography. • Diagnostic accuracy of CTCA+CTP is comparable to invasive angiography + fractional flow reserve

1863 map of the business portion of Cincinnati, Ohio partial closeup

This is a composite of two photos stitched together of a map measuring 30 in wide x 42.375 in tall. This enables some ability to zoom in on details

1863 map of the business portion of Cincinnati, Ohio, closeup

This is a composite of six photos stitched together of a map measuring 30 in wide x 42.375 tall. This makes it possible to zoom in closely on the details

Calixarene/azolium cyclophane hybrids: Synthesis, structure and conformations

© Springer Science+Business Media Dordrecht 2015.The synthesis, structure, and conformational behaviour of three imidazolium cyclophanes that incorporate one or two 4-tert-butylphenol or 4-tert-butylanisole groups as meta-disubstituted linkers in the macrocycle is described. The cyclophanes containing anisole moieties adopt a cone conformation in the solid state, which, in solution, is not labile on the NMR timescale. The cyclophanes containing one or two phenol moieties adopt conformations other than the cone in the solid state and are labile in solution on the NMR timescale. The phenol cyclophanes are readily deprotonated, and structural and conformational studies for a variety of the associated cyclophanes are also reported