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Aims There is rising healthcare utilization related to the increasing incidence and prevalence of atrial fibrillation (AF) worldwide. Simplifying therapy and reducing hospital episodes would be a valuable development. The efficacy of a streamlined AF ablation approach was compared to drug therapy and a conventional catheter ablation technique for symptom control in paroxysmal AF. Methods and results We recruited 321 patients with symptomatic paroxysmal AF to a prospective randomized, multi-centre, open label trial at 13 UK hospitals. Patients were randomized 1:1:1 to cryo-balloon ablation without electrical mapping with patients discharged same day [Ablation Versus Anti-arrhythmic Therapy for Reducing All Hospital Episodes from Recurrent (AVATAR) protocol]; optimization of drug therapy; or cryo-balloon ablation with confirmation of pulmonary vein isolation and overnight hospitalization. The primary endpoint was time to any hospital episode related to treatment for atrial arrhythmia. Secondary endpoints included complications of treatment and quality-of-life measures. The hazard ratio (HR) for a primary endpoint event occurring when comparing AVATAR protocol arm to drug therapy was 0.156 (95% CI, 0.097–0.250; P < 0.0001 by Cox regression). Twenty-three patients (21%) recorded an endpoint event in the AVATAR arm compared to 76 patients (74%) within the drug therapy arm. Comparing AVATAR and conventional ablation arms resulted in a non-significant HR of 1.173 (95% CI, 0.639–2.154; P = 0.61 by Cox regression) with 23 patients (21%) and 19 patients (18%), respectively, recording primary endpoint events (P = 0.61 by log-rank test). Conclusion The AVATAR protocol was superior to drug therapy for avoiding hospital episodes related to AF treatment, but conventional cryoablation was not superior to the AVATAR protocol. This could have wide-ranging implications on how demand for AF symptom control is met. Trial registration Clinical Trials Registration: NCT02459574.

Background Left bundle area pacing is growing in use both for bradycardia pacing and cardiac resynchronization, but implants are not always successful. We prospectively studied consecutive patients to determine whether septal scar contributes to implant failure. Methods Patients scheduled for left bundle area pacing, using the 3830 Selectsecure lead were prospectively enrolled. All patients underwent standardized scar assessment by cardiac MRI with late gadolinium enhancement imaging. Scar burden was quantified as the proportion of basal septal segments showing late enhancement. Results 35 patients were recruited: 29 male, mean age 68 years, 10 with ischemic and 16 with dilated cardiomyopathy. Pacing indication was bradycardia in 26% and cardiac resynchronization in 74%. In 5/35 (14%) it was not possible to advance the lead through the ventricular septum. Basal septal late gadolinium enhancement was significantly more extensive in these patients (median 67%, IQR 58-69.5) compared to the other 30 (median 10%, IQR 0-20, p = 0.0006). There was no significant correlation between the paced QRS duration achieved and the extent of basal septal scar (r = 0.06, P = 0.75). Conclusions Failure to deliver a lead to the left bundle area is strongly associated with a (very) high burden of scar in the basal septum. Once the lead is delivered, however, the electrical response is independent of scar burden. This suggests that it would be worth developing delivery tools to tackle scarred basal septa, because if the lead could be delivered the electrical capture might still achieve a narrow QRS.

PURPOSE: To assess whether the semisupervised natural language processing (NLP) of text from clinical radiology reports could provide useful automated diagnosis categorization for ground truth labeling to overcome manual labeling bottlenecks in the machine learning pipeline. MATERIALS AND METHODS: In this retrospective study, 1503 text cardiac MRI reports from 2016 to 2019 were manually annotated for five diagnoses by clinicians: normal, dilated cardiomyopathy (DCM), hypertrophic cardiomyopathy, myocardial infarction (MI), and myocarditis. A semisupervised method that uses bidirectional encoder representations from transformers (BERT) pretrained on 1.14 million scientific publications was fine-tuned by using the manually extracted labels, with a report dataset split into groups of 801 for training, 302 for validation, and 400 for testing. The model's performance was compared with two traditional NLP models: a rule-based model and a support vector machine (SVM) model. The models’ F1 scores and receiver operating characteristic curves were used to analyze performance. RESULTS: After 15 epochs, the F1 scores on the test set of 400 reports were as follows: normal, 84%; DCM, 79%; hypertrophic cardiomyopathy, 86%; MI, 91%; and myocarditis, 86%. The pooled F1 score and area under the receiver operating curve were 86% and 0.96, respectively. On the same test set, the BERT model had a higher performance than the rule-based model (F1 score, 42%) and SVM model (F1 score, 82%). Diagnosis categories classified by using the BERT model performed the labeling of 1000 MR images in 0.2 second. CONCLUSION: The developed model used labels extracted from radiology reports to provide automated diagnosis categorization of MR images with a high level of performance. Keywords: Semisupervised Learning, Diagnosis/Classification/Application Domain, Named Entity Recognition, MRI Supplemental material is available for this article. © RSNA, 2021

Aims: A prolonged PR interval may adversely affect ventricular filling and therefore cardiac function. AV delay can be corrected using right-ventricular-pacing (RVP) but this induces ventricular dyssynchrony, itself harmful. Therefore, in intermittent heart-block, pacing-avoidance algorithms are often implemented. We tested His-bundle pacing (HBP) as an alternative. Methods: Out-patients with a long PR interval(>200ms) and intermittent need for ventricular pacing were recruited. We measured within patient differences in high-precision haemodynamics between AV-optimized RVP, and HBP, as well as a pacing-avoidance algorithm [Managed Ventricular Pacing (MVP)]. Results We recruited 18 patients. Mean left ventricular ejection fraction was 44.3±9%. Mean intrinsic PR interval was 266±42ms and QRS duration was 123±29ms. RVP lengthened QRS duration(+54 ms, 95%CI 42 to 67ms, p

Aims Rate adaptation of the action potential ensures spatial heterogeneities in conduction across the myocardium are minimized at different heart rates providing a protective mechanism against ventricular fibrillation (VF) and sudden cardiac death (SCD), which can be quantified by the ventricular conduction stability (V-CoS) test previously described. We tested the hypothesis that patients with a history of aborted SCD due to an underlying channelopathy or cardiomyopathy have a reduced capacity to maintain uniform activation following exercise. Methods and results Sixty individuals, with (n = 28) and without (n = 32) previous aborted-SCD event underwent electro-cardiographic imaging recordings following exercise treadmill test. These included 25 Brugada syndrome, 13 hypertrophic cardiomyopathy, 12 idiopathic VF, and 10 healthy controls. Data were inputted into the V-CoS programme to calculate a V-CoS score that indicate the percentage of ventricle that showed no significant change in ventricular activation, with a lower score indicating the development of greater conduction heterogeneity. The SCD group, compared to those without, had a lower median (interquartile range) V-CoS score at peak exertion [92.8% (89.8–96.3%) vs. 97.3% (94.9–99.1%); P Conclusion Data from this pilot study demonstrate the potential use of this technique in risk stratification for the inherited cardiac conditions.