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Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): None Previous studies have shown that an increase of epicardial adipose tissue (EAT) volume is an independent risk factor of atrial fibrillation (AF) occurrence. However, there is no reliable data about the relationship between EAT and AF recurrence after catheter ablation (CA). Also, there are no studies of the possibility of using of CT radiomics of EAT, in particular of the quantitative assessment of EAT textural changes, for prognosis of CA outcomes in patients with AF. Thus, the aim of the present study was to estimate the association of CT-radiomics features of EAT with probability of AF recurrence after catheter ablation. Materials and Methods The prospective research included 46 patients (42 males and 4 females, mean age 42.4 ± 9.36) with drug-refractory lone AF referred for catheter ablation (CA). Before CA all patients underwent multislice CT-angiography for preoperative evaluation of cardiac and vessels anatomy and volumes. Images were acquired using a 64-detector CT scanner (GE Discovery NM/CT 570c, GE Healthcare, Milwaukee, WI, USA). Imaging parameters included a gantry rotation time of 400 ms, tube voltage of 120 mA, slice thickness 1.25 mm. For evaluation of EAT only native images (contrast-free scans) without ECG synchronization were analyzed. Epicardial adipose tissue segmentation was performed by 3D-Sliser software and the SliserRadiomics module (version 4.10.2). From CT images we quantified EAT volume and 93 radiomic features, including subgroups of first-order statistics, GLCM, GLDM, GLRLM, GLSZM and NGTDM parameters. All patients were followed-up prospectively for 12 months after the CA. A blanking period of 3 months was applied. The criteria of AF recurrence were AF episodes of more than 30 sec duration. Results. Recurrence of AF was registered in 26 patients. After the end of the follow-up, we divided study population on those with (Group 1) and without (Group 2) AF recurrence. EAT volume and attenuation values for Group 1 were 176.6 ± 56.9 sm3 and -77.47 ± 2.2 HU respectively; for Group 2 were 174.05 ± 73.3 sm3 and -78.42 ± 3.3 HU respectively, with no significant differences (p In the same time, 16 of 93 CT radiomics EAT parameters were significantly different between Group 1 and Group 2 and were significantly associated with AF recurrence after CA according to univariable logistic analyses. Multivariate regression analysis demonstrated that only Gray Level Non-Uniformity Normalized (GLNUN of GLSZM) parameter was an independent predictor of AF recurrence (Odds ratio 1.0022, 95%Cl 1.0006 to 1.0038, p = 0.0013); ROC-curve analysis data showed that GLNUN > 1227.2 indicates high probability of AF recurrence during 12 months (sensitivity 84.2 %, specificity 70.8 %, AUC:0.765; p = 0.001). Conclusion radiomic biomarkers of EAT have a potential to serve as a predictors of AF recurrence after CA.

To assess the similarity of the behavioural effects of the rapid transcranial magnetic stimulation (rTMS) to those produced by other antidepressant treatments, in particular to repeated electroconvulsive shock (ECS), we carried out experiments on Wistar rats. The effects of a standard ECS procedure (9 daily treatments; the current parameters: 150 mA, 50 Hz, 0.5 s) were compared with 18 d treatment with rTMS of the same field intensity of 1.6 T but with different stimulation frequency (20 or 30 Hz) and a different number of sessions (9 or 18). Twenty-four hours after the last treatment the forced swimming test was carried out and the immobility time was recorded. The standard ECT reduced the immobility by 50%, the intensive rTMS (90 or 104 K impulses for the whole period of treatment) caused a significant effect, although smaller than that induced by ECT (reduction by 20-30%). The stimulation at 20 Hz required 18 treatment sessions to produce a significant effect, while only 9 sessions with stimulation at 30 Hz were sufficient to produce a comparable result. This suggests that the effectiveness of rTMS may be augmented by increasing the number or frequency of rTMS impulses.

Dr Gaynor: So what shunt, what operation would you do for that patient? Dr Photiadis: Right now I think there is no data. Our data do not show it, and there are no other data, so we would still use the B-T shunt. Dr. S. Sano (Okayama, Japan): Yes, a Sano would be probably a reasonable alternative. Dr Gaynor: That is the one finding that did come out in your studies. Dr E. Bove (Ann Arbor, MI, USA): I enjoyed your paper, and I agree with your conclusion, but I rise to support what Dr. Gaynor said, and I think that we have to be very careful how we interpret data. It is a retrospective study, and if I understood from your abstract, it was surgeon preference which was not very clear. Does that mean one surgeon did one technique, another surgeon did a different one so that each surgeon decided preoperatively what he felt would be the best shunt? Additionally, looking at postoperative risk factors and showing that the Aristotle scores are equal does not have the same validity as a prospective randomized trial to reach the conclusion as you have reached. So even though I would like to agree with your conclusion, I think we have to be very careful how we interpret these data. Dr Photiadis: You are absolutely right, but again, randomisation may not give you the whole answer. If we have a patient, say aortic atresia, mitral atresia, who is stable preoperatively and whom you randomly assign to the Sano shunt, and then you have another patient with aortic atresia and mitral atresia, same anatomic type, was not prenatally diagnosed, decompensation without closure of the duct and cannot be stabilised, if you look on just the anatomic type, they are the same, but with respect to preoperative risk in fact they are not. By means of the Aristotle score these differences can be detected, with one patient being assigned to the low-risk and the other one to the high-risk group.