James M. Otton

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BACKGROUND Limitations to the coronary calcium score include its requirement for noncontrast imaging and radiation exposure that approaches current methods for contrast-enhanced CT angiography. OBJECTIVES We sought to derive and validate a method of measuring the coronary artery calcium score (CACS) from standard contrast-enhanced CT, obviating the need(More)
BACKGROUND T1 mapping is a robust and highly reproducible application to quantify myocardial relaxation of longitudinal magnetisation. Available T1 mapping methods are presently site and vendor specific, with variable accuracy and precision of T1 values between the systems and sequences. We assessed the transferability of a T1 mapping method and determined(More)
OBJECTIVES The aim of this study was to determine the contribution of pre-load and heart rate to pump flow in patients implanted with continuous-flow left ventricular assist devices (cfLVADs). BACKGROUND Although it is known that cfLVAD pump flow increases with exercise, it is unclear if this increment is driven by increased heart rate, augmented(More)
BACKGROUND Acute coronary syndrome (ACS) along with myocardial ischemic injury are the leading causes for chest pain. Platelet surface expression of stromal-cell-derived factor-1 (SDF-1) is enhanced during ischemic events and may play an important role in trafficking hematopoietic progenitor cells for tissue regeneration and neovascularization. This study(More)
Although pulmonary toxicity from sirolimus is well recognized, the biochemically homologous everolimus has until recently been thought to be free from this side effect. Emerging evidence suggests an association between high-dose everolimus and symptomatic pneumonitis. Toxicity at typical immunosuppressive doses has also been described. In support of these(More)
The aim of this article is to describe a novel hardware perfusion phantom that simulates myocardial first-pass perfusion allowing comparisons between different MR techniques and validation of the results against a true gold standard. MR perfusion images were acquired at different myocardial perfusion rates and variable doses of gadolinium and cardiac(More)
BACKGROUND Aggressive dose reduction strategies for cardiac CT require the prospective selection of limited cardiac phases. At lower heart rates, the period of mid-diastole is typically selected for image acquisition. We aimed to identify the effect of heart rate on the optimal CT acquisition phase within the period of mid-diastole. METHODS We utilized(More)
BACKGROUND Image noise and multiple sources of artifact may affect the accurate interpretation of myocardial CT perfusion (CTP) studies. Although artifact within the image is often time dependent, tissue characteristics remain unchanged irrespective of cardiac phase. OBJECTIVE We assessed a new technique of 4-dimensional, spatiotemporal analysis, using(More)
BACKGROUND Direct comparison of CT and magnetic resonance (MR) perfusion techniques has been limited and in vivo assessment is affected by physiological variability, timing of image acquisition, and parameter selection. OBJECTIVE We precisely compared high-resolution k-t SENSE MR cardiac perfusion at 3 T with single-phase CT perfusion (CTP) under(More)
analysis must include, not only those who undergo the procedure, but also those in whom the procedure was deferred. In 2012, Joynt et al. attempted to answer this question by exploring the outcomes of all patients with myocardial infarction in states that adopted public reporting, compared with those that did not. They found that in states with public(More)