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Electrocardiography (ECG) is a key non-invasive diagnostic tool for cardiovascular diseases which is increasingly supported by algorithms based on machine learning. Major obstacles for the development of automatic ECG interpretation algorithms are both the lack of public datasets and well-defined benchmarking procedures to allow comparison s of different algorithms. To address these issues, we put forward PTB-XL, the to-date largest freely accessible clinical 12-lead ECG-waveform dataset comprising 21837 records from 18885 patients of 10 seconds length. The ECG-waveform data was annotated by up to two cardiologists as a multi-label dataset, where diagnostic labels were further aggregated into super and subclasses. The dataset covers a broad range of diagnostic classes including, in particular, a large fraction of healthy records. The combination with additional metadata on demographics, additional diagnostic statements, diagnosis likelihoods, manually annotated signal properties as well as suggested folds for splitting training and test sets turns the dataset into a rich resource for the development and the evaluation of automatic ECG interpretation algorithms. Measurement(s) electrocardiography • cardiovascular system Technology Type(s) 12 lead electrocardiography Factor Type(s) presence of co-occurring diseases Sample Characteristic - Organism Homo sapiens Machine-accessible metadata file describing the reported data: 10.6084/m9.figshare.12098055 [ABSTRACT FROM AUTHOR]

Introduction: Multiple cardiac magnetic resonance (CMR)‐derived indices of atrial fibrillation (AF) substrate have been shown in isolation to predict long‐term outcome following catheter ablation. Left atrial (LA) fibrosis, LA volume, LA ejection fraction (EF), left ventricular ejection fraction (LVEF), LA shape (sphericity) and pulmonary vein anatomy have all been shown to correlate with late AF recurrence. This study aimed to validate and assess the relative contribution of multiple indices in a long‐term single‐center study. Methods and Results: Eighty‐nine patients (53% paroxysmal AF, 73% male) underwent comprehensive CMR study before first‐time AF ablation (median follow‐up 726 days [IQR: 418‐1010 days]). The 3D late gadolinium‐enhanced acquisition (1.5T, 1.3 × 1.3 × 2 mm) was quantified for fibrosis; LA volume and sphericity were assessed on manual segmentation at atrial diastole; LAEF and LVEF were quantified on multislice cine imaging. AF recurred in 43 patients (48%) overall (31 at 1 year). In the recurrence group, LA fibrosis was higher (42% vs 29%; hazard ratio [HR]: 1.032; P = .002), left atrial ejection fraction (LAEF) lower (25% vs 34%; HR: 0.063; P = .016) and LVEF lower (57% vs 63%; HR: 0.011; P = .008). LA volume (135 vs 124 mL) and sphericity (0.819 vs 0.822) were similar. Multivariate Cox regression analysis was adjusted for age and sex (Model 1), additionally AF type (Model 2) and combined (Model 3). In Models 1 and 2, LA fibrosis, LAEF, and LVEF were independently associated with outcome, but only LA fibrosis was independent in Model 3 (HR: 1.021; P = .022). Conclusions: LAEF, LVEF, and LA fibrosis differed significantly in the AF recurrence cohort. However, on combined multivariate analysis only LA fibrosis remained independently associated with outcome. [ABSTRACT FROM AUTHOR]

The article discusses a proposed technique for three-dimensional (3D) visualization of active catheters from triplanar two-dimensional (2D) projection magnetic resonance (MR) images. This technique employs compressed sensing (CS) to further lessen measurement times. A single-channel catheter design combining a solenoidal tip coil in series with a single-loop antenna is presented. This design allows to perform shape visualization and tip tracking simultaneously.

An abstract of the article "Standardization of myocardial T1 time measurements in clinical setting using MOLLI, shMOLLI and LL at 1.5T and 3T - the CONSEPT study," by Toby Rogers and colleagues is presented.

Background: Cardiovascular magnetic resonance (CMR) imaging may be used to visualize post-ablation atrial scar (PAAS), and three-dimensional late gadolinium enhancement (3D LGE) is the most widely employed technique for imaging of chronic scar. Detection of PAAS provides a unique non-invasive insight into the effects of the ablation and may help guide further ablation procedures. However, there is evidence that PAAS is often not detected by CMR, implying a significant sensitivity problem, and imaging parameters vary between leading centres. Therefore, there is a need to establish the optimal imaging parameters to detect PAAS. Methods: Forty subjects undergoing their first pulmonary vein isolation procedure for AF had detailed CMR assessment of atrial scar: one scan pre-ablation, and two scans post-ablation at 3 months (separated by 48 h). Each scan session included ECG- and respiratory-navigated 3D LGE acquisition at 10, 20 and 30 min post injection of a gadolinium-based contrast agent (GBCA). The first post-procedural scan was performed on a 1.5 T scanner with standard acquisition parameters, including double dose (0.2 mmol/kg) Gadovist and 4 mm slice thickness. Ten patients subsequently underwent identical scan as controls, and the other 30 underwent imaging with a reduced, single, dose GBCA (n = 10), half slice thickness (n = 10) or on a 3 T scanner (n = 10). Apparent signal-to-noise (aSNR), contrast-to-noise (aCNR) and imaging quality (Likert Scale, 3 independent observers) were assessed. PAAS location and area (%PAAS scar) were assessed following manual segmentation. Atrial shells with standardised %PAAS at each timepoint were then compared to ablation lesion locations to assess quality of scar delineation. Results: A total of 271 3D acquisitions (out of maximum 280, 96.7%) were acquired. Likert scale of imaging quality had high interobserver and intraobserver intraclass correlation coefficients (0.89 and 0.96 respectively), and showed lower overall imaging quality on 3 T and at half-slice thickness. aCNR, and quality of scar delineation increased significantly with time. aCNR was higher with reduced, single, dose of GBCA (p = 0.005). Conclusion: 3D LGE CMR atrial scar imaging, as assessed qualitatively and quantitatively, improves with time from GBCA administration, with some indices continuing to improve from 20 to 30 min. Imaging should be performed at least 20 min post-GBCA injection, and a single dose of contrast should be considered. Trial registration: Trial registry- United Kingdom National Research Ethics Service 08/H0802/68 – 30th September 2008. [ABSTRACT FROM AUTHOR]

An abstract of the article "A comparison of late gadolinium enhancement magnetic resonance imaging and left atrial endocardial voltage," by James Harriso, Nick Linton, Steven Williams, Rashed Karim, Kawal Rhode, Matthew Wright, Tobias Schaeffter, Reza Razavi and Mark O'Neill is presented.

An abstract of the article "Age-gender reference values of native myocardial T1 at 1.5T and 3T: comparison of MOLLI and shMOLLI," by Darius Dabir, Toby Rogers and Tobias Voigt is presented.

An abstract of the article "Dual-IR late gadolinium enhancement achieves better blood suppression than traditional IR in a swine model of atrial radiofrequency ablation scar," by Sarah A. Peel and colleagues is presented.

An abstract of the article "Magnetic resonance imaging of acute and chronic atrial ablation injury-a histological validation study," by James Harrison and colleagues is presented.

An abstract of the article "MR-guided cardiac radiofrequency ablation with catheter-tracked local MR lesion monitoring," by Steffen Weiss and colleagues is presented.

An abstract of the article "Prediction of gaps in atrial ablation lesion sets by late gadolinium enhancement magnetic resonance imaging," by James Harrison, Nick Linton, Steven Williams, and colleagues is presented.

An abstract of the article "A quantitative high resolution assessment of myocardial blood flow from contrast-enhanced first-pass magnetic resonance perfusion imaging: microsphere validation in a magnetic resonance compatible free beating explanted pig heart model," by Andreas Schuster, et al. is presented.

An abstract of the article "Are T1 values to characterize myocardial tissue equivalent between various sequences: comparison of MOLLI, shMOLLI, 3'5-MOLLI and SASHA," by Valentina O. Puntmann, Tobias Voigt, Darius Dabir, Toby Rogers, Tobias Schaeffter and Eike Nagel is presented.