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Aims: There is a lack of therapies able to prevent anthracycline cardiotoxicity (AC). Remote ischaemic conditioning (RIC) has shown beneficial effects in preclinical models of AC. Methods: REmote iSchemic condItioning in Lymphoma PatIents REceiving ANthraCyclinEs (RESILIENCE) is a multinational, prospective, phase II, double‐blind, sham‐controlled, randomized clinical trial that evaluates the efficacy and safety of RIC in lymphoma patients receiving anthracyclines. Patients scheduled to undergo ≥5 chemotherapy cycles including anthracyclines and with ≥1 AC‐associated risk factors will be randomized to weekly RIC or sham throughout the chemotherapy period. Patients will undergo three multiparametric cardiac magnetic resonance (CMR) studies, at baseline, after the third cycle (intermediate CMR), and 2 months after the end of chemotherapy. Thereafter, patients will be followed up for clinical events over an anticipated median of ≥24 months. The primary endpoint is the absolute change from baseline in CMR‐based left ventricular ejection fraction (LVEF). The main secondary outcome is the incidence of AC events, defined as (1) a drop in CMR‐based LVEF of ≥10 absolute points, or (2) a drop in CMR‐based LVEF of ≥5 and <10 absolute points to a value <50%. Intermediate CMR will test the ability of T2 mapping to predict AC versus classical markers (left ventricular strain and cardiac injury biomarkers). A novel CMR sequence allowing ultrafast cine acquisition will be validated in this vulnerable population. Conclusions: The RESILIENCE trial will test RIC (a novel non‐invasive intervention to prevent AC) in a cohort of high‐risk patients. The trial will also test candidate markers for their capacity to predict AC and will validate a novel CMR sequence reducing acquisition time in a vulnerable population. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate a silent MR active catheter tracking sequence that allows conducting catheter interventions with low acoustic noise levels. Methods: To reduce the acoustic noise associated with MR catheter tracking, we implemented a technique previously used in conventional MRI. The gradient waveforms are modified to reduce the sound pressure level (SPL) and avoid acoustic resonances of the MRI system. The efficacy of the noise reduction was assessed by software‐predicted SPL and verified by measurements. Furthermore, the quality of the catheter tracking signal was assessed in a phantom experiment and during interventional cardiovascular MRI sessions targeted at isthmus‐related flutter ablation. Results: The maximum measured SPL in the scanner room was 104 dB(A) for real‐time imaging, and 88 dB(A) and 69 dB(A) for conventional and silent tracking, respectively. The SPL measured at different positions in the MR suite using silent tracking were 65–69 dB(A), and thus within the range of a normal conversation. Equivalent signal quality and tracking accuracy were obtained using the silent variant of the catheter tracking sequence. Conclusion: Our results indicate that silent MR catheter tracking capabilities are identical to conventional catheter tracking. The achieved acoustic noise reduction comes at no penalty in terms of tracking quality or temporal resolution, improves comfort and safety, and can overcome the need for MR‐compatible communication equipment and background noise suppression during the actual interventional procedure. [ABSTRACT FROM AUTHOR]

Background: In congenital heart disease (CHD) patients, detailed three-dimensional anatomy depiction plays a pivotal role for diagnosis and therapeutical decision making. Hence, the present study investigated the applicability of an advanced cardiovascular magnetic resonance (CMR) whole heart imaging approach utilizing nonselective excitation and compressed sensing for anatomical assessment and interventional guidance of CHD patients in comparison to conventional dynamic CMR angiography. Methods: 86 consecutive pediatric patients and adults with congenital heart disease (age, 1 to 74 years; mean, 35 years) underwent CMR imaging including a freebreathing, ECG-triggered 3D nonselective SSFP whole heart acquisition using compressed SENSE (nsWHcs). Anatomical assessability and signal intensity ratio (SIR) measurements were compared with conventional dynamic 3D-/4D-MR angiography. Results: The most frequent diagnoses were partial anomalous pulmonary venous drainage (17/86, 20%), transposition of the great arteries (15/86, 17%), tetralogy of Fallot (12/86, 14%), and a single ventricle (7/86, 8%). Image quality of nsWHcs was rated as excellent/good in 98% of patients. nsWHcs resulted in a reliable depiction of all large thoracic vessels (anatomic assessability, 99%–100%) and the proximal segments of coronary arteries and coronary sinus (>90%). nsWHcs achieved a homogenously distributed SIR in all cardiac cavities and thoracic vessels without a significant difference between pulmonary and systemic circulation (10.9 ± 3.5 and 10.6 ± 3.4; p = 0.15), while 3D angiography showed significantly increased SIR for targeted vs. non-targeted circulation (PA-angiography, 15.2 ± 8.1 vs. 5.8 ± 3.6, p < 0.001; PV-angiography, 7.0 ± 3.9 vs. 17.3 ± 6.8, p < 0.001). Conclusions: The proposed nsWHcs imaging approach provided a consistently high image quality and a homogeneous signal intensity distribution within the pulmonary and systemic circulation in pediatric patients and adults with a wide spectrum of congenital heart diseases. nsWHcs enabled detailed anatomical assessment and three-dimensional reconstruction of all cardiac cavities and large thoracic vessels and can be regarded particularly useful for preprocedural planning and interventional guidance in CHD patients. [ABSTRACT FROM AUTHOR]

Purpose: To develop a new 3D radial trajectory based on the natural spiral phyllotaxis (SP), with variable anisotropic FOV. Theory & Methods: A 3D radial trajectory based on the SP with favorable interleaving properties for cardiac imaging has been proposed by Piccini et al (Magn Reson Med. 2011;66:1049‐1056), which supports a FOV with a fixed anisotropy. However, a fixed anisotropy can be inefficient when sampling objects with different anisotropic dimensions. We extend Larson's 3D radial method to provide variable anisotropic FOV for spiral phyllotaxis (VASP). Simulations were performed to measure distance between successive projections, analyze point spread functions, and compare aliasing artifacts for both VASP and conventional SP. VASP was fully implemented on a whole‐body clinical MR scanner. Phantom and in vivo cardiac images were acquired at 1.5 tesla. Results: Simulations, phantom, and in vivo experiments confirmed that VASP can achieve variable anisotropic FOV while maintaining the favorable interleaving properties of SP. For an anisotropic FOV with 100:100:35 ratio, VASP required ~65% fewer radial projections than the conventional SP to satisfy Nyquist criteria. Alternatively, when the same number of radial projections were used as in conventional SP, VASP produced fewer aliasing artifacts for anisotropic objects within the excited imaging volumes. Conclusion: We have developed a new method (VASP), which enables variable anisotropic FOV for 3D radial trajectory with SP. For anisotropic objects within the excited imaging volumes, VASP can reduce scan times and/or reduce aliasing artifacts. [ABSTRACT FROM AUTHOR]

Aims To determine safety and efficacy of electrophysiological cardiovascular magnetic resonance (EP-CMR)-guided radiofrequency (RF) ablation in patients with typical right atrial flutter in a routine clinical setting. Methods and results Thirty patients with typical right atrial flutter underwent clinically indicated EP-CMR-guided cavotricuspid isthmus ablation. EP-CMR protocols included pre- and post-ablation CMR imaging (whole heart, T2-weighted, and early-/late-gadolinium enhancement) together with electroanatomic mapping of the right atrium. Coronary sinus cannulation time and total ablation procedure duration were used as performance measures to determine the learning experience of the EP-CMR interventionalist and for comparison with conventional, fluoroscopy-guided atrial flutter ablation. Procedural safety and success rates were evaluated at 1 week and 3 months follow-up. Safety and success rates of EP-CMR were similar to conventional flutter ablations (primary success rate, 93% vs. 100%; recurrence rate, 0% vs. 3%, respectively). EP-CMR procedure duration indicated a learning experience (first vs. last six patients, 54.2 ± 23.1 vs. 29.7 ± 20.0 min) and the minimum number of procedures needed to achieve a level of competency was n  = 12. An isthmus angle <110° and the presence of pouch-like isthmus anatomy were indicative of significantly prolonged EP-CMR procedure duration. CMR-defined ablation lesion size was not associated with total RF-ablation time or RF-induced maximum temperature. Conclusion In a routine clinical setting, EP-CMR demonstrated its safety and high efficacy for the treatment of typical right atrial flutter with performance and outcome measures similar to conventional, fluoroscopy-guided flutter ablation. Hence, EP-CMR represents a valid alternative to conventional right atrial flutter ablation. [ABSTRACT FROM AUTHOR]

Purpose: To propose a simultaneous acquisition sequence for improved hepatic pharmacokinetics quantification accuracy (SAHA) method for liver dynamic contrast‐enhanced MRI. Methods: The proposed SAHA simultaneously acquired high temporal‐resolution 2D images for vascular input function extraction using Cartesian sampling and 3D large‐coverage high spatial‐resolution liver dynamic contrast‐enhanced images using golden angle stack‐of‐stars acquisition in an interleaved way. Simulations were conducted to investigate the accuracy of SAHA in pharmacokinetic analysis. A healthy volunteer and three patients with cirrhosis or hepatocellular carcinoma were included in the study to investigate the feasibility of SAHA in vivo. Results: Simulation studies showed that SAHA can provide closer results to the true values and lower root mean square error of estimated pharmacokinetic parameters in all of the tested scenarios. The in vivo scans of subjects provided fair image quality of both 2D images for arterial input function and portal venous input function and 3D whole liver images. The in vivo fitting results showed that the perfusion parameters of healthy liver were significantly different from those of cirrhotic liver and HCC. Conclusions: The proposed SAHA can provide improved accuracy in pharmacokinetic modeling and is feasible in human liver dynamic contrast‐enhanced MRI, suggesting that SAHA is a potential tool for liver dynamic contrast‐enhanced MRI. Magn Reson Med 79:2629–2641, 2018. © 2017 International Society for Magnetic Resonance in Medicine. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to propose, optimize, and validate a pseudo-continuous arterial spin labeling (pCASL) sequence for simultaneous measurement of brain perfusion and labeling efficiency. Methods: The proposed sequence incorporates the labeling efficiency measurement into the postlabeling delay period of a conventional perfusion pCASL sequence by using the time-encoding approach. In vivo validation experiments were performed on nine young subjects by comparing it to separate perfusion and labeling efficiency sequences. Sensitivity of the proposed combined sequence for measuring labeling efficiency changes was further addressed by varying the flip angles of the pCASL labeling radiofrequency pulses. Results: The proposed combined sequence decreased the perfusion signal by ∼4% and a lower labeling efficiency (by ∼10%) was found as compared to the separate sequences. However, the temporal signal-noise-ratio of the perfusion signal remained unchanged. When the pCASL flip angle was decreased to a suboptimal setting, a strong correlation was found between the combined and the separate sequences for the relative change in pCASL perfusion signal as well as for the relative change in labeling efficiency. High correlation was also observed between relative changes in perfusion signal and the measured labeling efficiencies. Conclusion: The proposed sequence allows simultaneous measurement of brain perfusion and labeling efficiency with high time-efficiency at the price of only a small compromise in measurement accuracy. The additional labeling efficiency measurement can be used to facilitate qualitative interpretation of pCASL perfusion images. [ABSTRACT FROM AUTHOR]