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Electrocardiogram (ECG)-gated breath-hold cine MRI is considered to be the gold standard test for the assessment of cardiac function. However, it may fail in patients with arrhythmia, impaired breath-hold capacity and poor ECG gating. Although ungated real-time cine MRI may mitigate these problems, commercially available real-time cine MRI pulse sequences using parallel imaging typically yield relatively poor spatiotemporal resolution because of their low image acquisition efficiency. As an extension of our previous work, the purpose of this study was to evaluate the diagnostic quality and accuracy of eight-fold-accelerated real-time cine MRI with compressed sensing (CS) for the quantification of cardiac function in tachycardia, where it is challenging for real-time cine MRI to provide sufficient spatiotemporal resolution. We evaluated the performances of eight-fold-accelerated cine MRI with CS, three-fold-accelerated real-time cine MRI with temporal generalized autocalibrating partially parallel acquisitions (TGRAPPA) and ECG-gated breath-hold cine MRI in 21 large animals with tachycardia (mean heart rate, 104 beats per minute) at 3T. For each cine MRI method, two expert readers evaluated the diagnostic quality in four categories (image quality, temporal fidelity of wall motion, artifacts and apparent noise) using a Likert scale (1-5, worst to best). One reader evaluated the left ventricular functional parameters. The diagnostic quality scores were significantly different between the three cine pulse sequences, except for the artifact level between CS and TGRAPPA real-time cine MRI. Both ECG-gated breath-hold cine MRI and eight-fold accelerated real-time cine MRI yielded all four scores of ≥ 3.0 (acceptable), whereas three-fold-accelerated real-time cine MRI yielded all scores below 3.0, except for artifact (3.0). The left ventricular ejection fraction (LVEF) measurements agreed better between ECG-gated cine MRI and eight-fold-accelerated real-time cine MRI (mean difference, -1.6%) than between ECG-gated cine MRI and three-fold-accelerated real-time cine MRI (mean difference, -5.7%). Eight-fold-accelerated real-time cine MRI with CS yields acceptable diagnostic quality and relatively accurate LVEF measurements in the challenging setting of tachycardia. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Reports on the antagonism of central melanocortin receptors in vitro and in vivo by Agouti-related protein. The identification of an expressed sequence tag; What ubiquitous expression of human AGRP complementary DNA in transgenic mice caused; The suggestion that Agouti-related protein is a neuropeptide implicated in the normal control of body weight downstream of leptin signaling.

Objective: To evaluate the risk of heart disease related death (HDRD) following radiation therapy (RT) for esophageal cancer (EC)., Methods: Using the Surveillance, Epidemiology, and End Results (SEER) database, two cohorts of patients with EC were created: (I) patients who received RT with their initial therapy; and (II) those who did not. Heart disease specific survival (HDSS) was analyzed using Kaplan-Meier methods. Cox proportional-hazards regression methods were used for univariate and multivariate analyses., Results: We identified 40,778 patients with EC. A total of 26,377 patients received RT and 14,401 did not. HDSS analysis revealed increased risk of HDRD in those receiving RT (P<0.05), with an absolute risk of HDRD of 2.8%, 5.3% and 9.4% at 5-, 10- and 20-year, respectively. Log rank test of HDSS revealed the risk of HDRD became significant at 8 months (P<0.05). The following were associated with HDRD: RT, age, race, stage at presentation, time period of diagnosis, and known comorbid condition keeping one from esophagectomy. On multivariate analysis, RT remained predictive of HDRD [hazard ratio (HR) 1.46, P<0.05]. When considering only candidates for definitive therapy, RT remained predictive of HDRD on univariate (HR 1.53, P<0.0001) and multivariate (HR 1.62, P<0.0001) analyses., Conclusions: The use of RT leads to increased risk of HDRD that is detectable as early as eight months from diagnosis. More research is needed to define optimal dose volume parameters to prevent cardiac death. Consideration should be given to this risk in relation to prognosis and the expected benefits of RT.

Aim: Late gadolinium enhanced (LGE) magnetic resonance imaging (MRI) is a useful tool for facilitating ventricular tachycardia (VT) ablation. Unfortunately, most VT ablation candidates often have prophylactic implantable cardioverter-defibrillator (ICD) and do not undergo cardiac MRI largely due to image artefacts generated by ICD. A prior study has reported success of 'wideband' LGE MRI for imaging myocardial scar without image artefacts induced by ICD at 1.5T. The purpose of this study was to widen the availability of wideband LGE MRI to 3T, since it has the potential to achieve higher spatial resolution than 1.5T., Methods and Results: We compared the performance of standard and wideband LGE MRI pulse sequences in phantoms and canines with myocardial lesions created by radiofrequency ablation. Standard LGE MRI produced image artefacts induced by ICD and 49% accuracy in detecting 97 myocardial scars examined in this study, whereas wideband LGE MRI produced artefact-free images and 94% accuracy in detecting scars. The mean image quality score (1 = nondiagnostic, 2 = poor, 3 = adequate, 4 = good, 5 = excellent) was significantly (P < 0.001) higher for wideband (3.7 ± 0.8) than for standard LGE MRI (2.1 ± 0.7). The mean artefact level score (1 = minimal, 2 = mild, 3 = moderate, 4 = severe, 5 = nondiagnostic) was significantly (P < 0.001) lower for wideband (2.1 ± 0.8) than for standard LGE MRI (4.0 ± 0.6). Wideband LGE MRI agreed better with gross pathology than standard LGE MRI., Conclusion: This study demonstrates the feasibility of wideband LGE MRI for suppression of image artefacts induced by ICD at 3T., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.)