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Aims Pulmonary vein isolation (PVI) often is not sufficient in patients (pts) with persistent atrial fibrillation (AF). Substrate modification (SM) by catheter ablation (CA) of low-voltage zones (LVZ) has yielded favourable results, but those studies were performed before the introduction of contact force (CF) sensing technology. Surgical ablation (SA) studies support the hypothesis that empiric bi-atrial linear ablation (Cox Maze IV procedure) is able to improve success, but there is less data on outcome of patients undergoing left atrial (LA) linear lesions alone. In current guidelines, both CA and SA have Class IIa indication in pts with persistent AF. In this single-centre retrospective study, we analysed the long-term outcomes of CA and SA in pts with persistent AF. Methods and results In the CA group (Figure 1), pts underwent PVI and additional SM in the presence of LVZ (roof line and supero-septal line) using TactiCath™ or SmartTouch™ ablation catheters aiming at contact values ≥10 g 400 g/s. Ablation was performed in a temperature-controlled fashion with energy of 30 W except at the posterior wall (20–25 W). In the SA group (Figure 2), pts underwent ablation procedure (creation of a pure LA endocardial lesion set consistent with the Cox Maze IV) performed by a right mini-thoracotomy approach using the Atricure™ cryoablation probe, a left atrial appendage (LAA) epicardial exclusion using the Atriclip™ system, and mitral valve repair in the presence of severe mitral valve regurgitation. No right atrial lesions were created. 196 pts were included. 120 pts underwent CA [median age: 65 (58–72) years, median LA volume index (LAVI): 66 (56–75) ml/m2], in pts with LVZs PVI + SM was performed [bidirectional block of lines in 100%]. 76 pts underwent SA [median age: 64 (58–74) years, median LAVI 90 (78–103) ml/m2], in 42 pts a mitral valve repair was performed. At 24 months (figure), 89% and 68% of pts were free of AF in the SA and CA group, respectively, mainly without antiarrhythmic drugs (92% SA group and 89% CA group). Conclusions In patients with persistent AF, SA performed by a right mini-thoracotomy approach with linear lesions limited to LA leads to excellent 2-year freedom from AF despite significantly larger LAVI compared with the CA group. LAA epicardial exclusion likely contributed to surgical efficacy by eliminating the LAA as trigger/driver.

Introduction: Although pulmonary vein (PV) isolation (PVI) is very effective in paroxysmal atrial fibrillation (AF), in patients (pts) with persistent AF, PVI often is not sufficient. Many studies suggested that low voltage zones (LVZs) outside of the PV might be involved in the complex mechanisms perpetuating AF. However ablation strategies involving substrate modification (SM) did not show additional benefits in persistent AF pts. Those studies were performed before the introduction of contact force technology, and the most likely explanation for these results could be the inability to achieve effective transmural lesions and continuous linear ablation. Hypothesis: We hypothesized that the use of contact force technology would improve ablation efficacy. Therefore, we analyzed the long-term outcome after two different ablation strategies in pts with persistent AF depending on whether there was evidence of LVZs in the left atrium or not. Methods: The presence of LVZs were defined as sites of >3 adjacent low-voltage points 400g/s. Ablation was performed in a temperature-controlled fashion with energy of 30W except at the posterior wall (20-25W). Results: 121 consecutive pts with persistent AF (46 female, median age 66 [59-72] years, mean duration of AF 16 [7-73] months, CT derived LA volume index 66 [56-75]ml/m2) were included: pts without LVZs underwent PVI alone (n = 74), in pts with LVZs, PVI + SM (n = 47) was performed (mitral Isthmus line in 2, supero-septal line in 39, and roof line in 47; bidirectional block was achieved in 100%, 97%, and 100%, respectively). After a median follow-up of 13 [6-21] months, 86% of pts without and 78% with substrate were in sinus rhythm, mainly without antiarrhythmic drugs (89% PVI only, 84% PVI + SM). Conclusions: In patients with persistent AF without LVZs, PVI alone leads to excellent 2-year freedom from AF. In pts with LVZs, additional substrate modification with CF sensing technology is associated with improved success rates compared to previous studies.

Background Pulmonary vein isolation is the cornerstone of catheter ablation in patients with atrial fibrillation (AF). However, with advanced left atrial (LA) structural changes, additional targeted catheter ablation of low voltage zones (LVZs) has produced favorable results. Therefore, with the advent of single-shot techniques, it would be helpful to predict the presence of LVZs before an ablation procedure. Objective We hypothesized that computed tomography-derived (CT) left atrial volume index (LAVI), in combination with other objective parameters, could be used to develop a score able to predict the presence of LVZs. Methods In a large cohort of patients undergoing their first AF ablations, comprehensive echocardiographic evaluations and cardiac CT were performed. During the electrophysiological studies, LA geometry and electro-anatomic voltage maps were created. LVZs were defined as areas ≥1cm2 with bipolar peak-to-peak voltage amplitudes ≤0.5 mV. Results In a derivation cohort of 374 patients, predictors of LVZs were identified by regression analysis and used to build the ZAQ score (age≥65 years, female sex and CT LAVI≥57ml/m2). The ZAQ score of 2 points accurately identified the presence and the extent of LVZs (AUC 0.809, 95% CI 0.758-0.861, p Conclusions The ZAQ score identifies LVZs and may be useful for planning the ablation strategy ahead of time (single shot PVI vs 3D mapping-guided ablation) regardless of whether the AF pattern is paroxysmal or persistent. Figure legend. Proposed AF ablation workflow independent of the temporal pattern of AF (ie. paroxysmal vs. persistent). (CT) Computed Tomography, (LAVI) Left Atrial Volume Index, (PVI) Pulmonary vein isolation. *Low voltage zones, if present, could be targeted with additional substrate modification ablation Conflict of Interest None

BACKGROUND Pulmonary vein isolation is the cornerstone of catheter ablation in patients with atrial fibrillation (AF). However, with advanced left atrial (LA) structural changes, additional targeted catheter ablation of low-voltage zones (LVZs) has produced favorable results. Therefore, with the advent of single-shot techniques, it would be helpful to predict the presence of LVZs before an ablation procedure. OBJECTIVE We hypothesized that computed tomography (CT)-derived left atrial volume index (LAVI), in combination with other objective parameters, could be used to develop a score able to predict the presence of LVZs. METHODS In a large cohort of patients undergoing their first AF ablations, comprehensive echocardiographic evaluations and cardiac CT were performed. During the electrophysiological studies, LA geometry and electroanatomic voltage maps were created. LVZs were defined as areas ≥1 cm2 with bipolar peak-to-peak voltage amplitudes ≤0.5 mV. RESULTS In a derivation cohort of 374 patients, predictors of LVZs were identified by regression analysis and used to build the Zentralklinik Bad Berka and University of L'Aquila (ZAQ) score (age ≥65 years; female sex; and CT-LAVI ≥57 mL/m2 ). The ZAQ score of 2 points accurately identified the presence and the extent of LVZs (area under the curve [AUC], 0.809; 95% confidence interval [CI], 0.758-0.861; P

Background concentrations of the heavy metals Mn, Ni, Cd, Co, Zn, Cu, and Pb in the soils and plant monitors of the Boatin Reserve were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Surface soil layers of the Boatin Reserve were polluted with Cu, as its concentration exceeded both the national legal standards and the content of Cu in non-polluted areas. Analysis of heavy metals accumulation in all studied plant monitors indicated that the content of Cu, Pb, and Zn exceeded their concentration in non-polluted areas. It may be concluded that the heavy metals Cu, Pb, and Zn are the main pollutants in the Boatin Reserve.

Polyacrylamide gel electrophoresis was employed to study the isoenzyme variation of esterase and acid phosphatase in natural populations of Dasypyrum villosum (L.) P.Candargy, Elytrigia repens (L.) Nevski and Elymus caninus (L.) L. Four similarity indices (SI, S, D, Ih) were calculated in an attempt to evaluate quantitatively genetic affinities among the species examined. Considering index D, the species D. villosum proved to be equally distant (D = 0.17 in both cases) from the species pair Et. repens and El. caninus. The nearly twice lower value of D for the comparison between Et. repens and El. caninus is an indication of their stronger genetic relationship. Mean values of indices Ih, SI and S also indicated that D. villosum is the most distinct species within the group studied. The results were discussed in the light of chloroplast DNA sequence data, suggesting a close affinity among the genera Dasypyrum (Coss. & L.Durieu) T.Durand, Elytrigia Desv. and Elymus L. The results of the present isoenzyme study are not in congruence with cpDNA analysis. Both isoenzyme and DNA data suggest that the phylogenetic position of the genus Dasypyrum within the tribe Triticeae remains unresolved.

The subject of the investigation in this dissertation work are artefacts (ceramic fragments) from archeologic sites in Estern Rhodopes: sanctuaries “Gluhite kamani”, “Ada tepe”, “Menekenski kamani”, “Kodja kaq” and “Rezbartsi”, ritual pits: “Dolno cherkovishte”, settlement ‘’Biser”. All of them are from Early Iron age (ХІ-VІ BC). Finding from ceramic artefacts are with extremely important in clarifying human lifestyle and life. Ceramics have always been an important part of human life and culture in the past. Mineralogical-petrographic investigation of ceramic artefacts have essential in determining the method of manufacture, temperature and firing medium, materials from which they are made and the place from where the raw material was taken., Обект на изследвания в настоящия дисертационен труд са артефакти (керамични фрагменти) от археологически обекти в Източните Родопи: светилищата „Глухите камъни“, „Ада тепе“, „Менекенски камъни“, „Коджа кая“ и „Резбарци“; ритуални ями: „Долно черковище“; селище: „Бисер“ всички те от Ранната желязна епоха епоха (ХІ-VІ в. пр. Хр.). Находките от керамични артефакти са с изключителна важност при изясняването на развитието и бита на човека, керамиката винаги е била важна част от живота и културата в миналото. Минералого-петрографските изследвания на керамични находки имат съществено значение при определяне начина на изработка, температурата и средата на изпичане, материалите използвани за изработка и мястото от което е взета суровината за направата ѝ.