[Evaluation of the operator learning curve for radiofrequency ablation for atrioventricular nodal reentrant tachycardia].

Aim    The aim of this study was to determine the average minimum number of slow pathway ablation procedures required to reach a steady success rate among inexperienced operators.Material and Methods    We analyzed the consecutive AVNRT ablation procedures of three inexperienced operators for the rate of operational success and complications.Results    Operators performed a total of 156 AVNRT ablation procedures. There was no statistical significance between the three operators regarding the rate of success (p=0.69) and complications. There were significant differences between the operators in terms of procedure time, fluoroscopy time, and cumulative air kerma. The variability of procedure time and cumulative air kerma, both among three operators and within each operator, decreased significantly after the 25th case. Each operator was analyzed individually for the probability of success as related to the cumulative number of ablations. All trainee operators reached a success rate of 90 % at the 27th procedure.Conclusion    An average of 27 slow pathway ablation procedures should be performed by a beginner operator to achieve proficiency.

Integrating the Left Atrium Diameter to Improve the Predictive Ability of the Age, Creatinine, and Ejection Fraction Score for Atrial Fibrillation Recurrence After Cryoballoon Ablation.

BACKGROUND: Several clinical trials have assessed predictors for atrial fibrillation recurrence following cryoballoon catheter ablation. With these predictors, a practical and new scoring system can be developed to evaluate atrial fibrillation recurrence. The present study aimed to analyze the predictive value of the age, creatinine, and ejection fraction-left atrium score for potential recurrence of atrial fibrillation following cryoballoon catheter ablation in patients with symptomatic paroxysmal or persistent atrial fibrillation. METHODS: We retrospectively analyzed records of patients undergoing cryoballoon cath-eter ablation. atrial fibrillation recurrence was defined as an emerging atrial fibrillation episode around 12-month follow-up (with the exclusion of a 3-month blanking period). Univariate and multivariate analyses were performed to assess predictors of atrial fibrillation recurrence. In addition, receiver operating characteristic analysis was harnessed to evaluate the performance of the age, creatinine, and ejection fraction, left atrium score in determining the risk of atrial fibrillation recurrence. RESULTS: The study population comprised 106 subjects (age 52 ± 13 years, 63.2% women) with paroxysmal (84.9%, n = 90) or persistent (15.1%, n = 16) atrial fibrillation. age, creatinine, and ejection fraction, left atrium score was significantly higher in subjects with atrial fibrillation recurrence in comparison to those with the maintenance of sinus rhythm. However, on multivariate logistic regression analysis, only the age, creatinine, and ejection fraction, left atrium score (OR = 12.93, 95% CI: 2.22-75.21, P =.004) served as an independent predictor of atrial fibrillation recurrence following cryoballoon catheter ablation. CONCLUSION: Age, creatinine, and ejection fraction, left atrium score had an independent association with the risk of atrial fibrillation recurrence in subjects with atrial fibrillation undergoing cryoballoon catheter ablation. Therefore, this score might potentially serve as a useful tool for risk stratification of patients with atrial fibrillation.

New coumarin glycosides from endemic Prangos heyniae H. Duman & M.F. Watson.

Two new coumarin glycosides, named 7-methoxy isoarnottinin 4'-O-ß-ᴅ-glucopyranoside and 7-methoxy isoarnottinin 4'-O-rutinoside (1 and 2) along with six known compounds (3-8) were isolated from the roots of Prangos heyniae, an endemic plant of Turkey. 1-methylethyl 6-O-D-apio-ß-ᴅ-furanosyl-ß-ᴅ-glucopyranoside (7) and cnidioside A (8) have been obtained from the genus Prangos for the first time. Structures of isolated compounds were established using spectroscopic methods (1 D and 2 D NMR, HR-MS, UV and IR). Moreover, all extracts and isolated compounds were evaluated for their cytotoxic activity against NIH/3T3, HK-2, A-549, MCF-7, PC-3 and SH-SY5Y cell lines by WST-1 method. One of the new coumarin glycosides, 7-methoxy isoarnottinin 4'-O-ß-ᴅ-glucopyranoside (1) exhibited selective cytotoxic activity against SH-SY5Y cells with IC50 value of 31.41 ± 1.04 µM.

Investigation of microwave extraction of red cabbage and its neurotherapeutic potential.

In the pursuit of bioactive compounds with health benefits from food and medicinal plants, optimization of process to reduce solvent, raw material, energy and time consumption has been a valuable research objective. Sustainable management and efficient use of natural resources are of critical importance for sustainability goals. In this manner, microwave extraction of red cabbage which has been a mass cultivated plant for food purposes, was optimized for maximizing acetylcholinesterase, butyrylcholinesterase, tyrosinase inhibitory activity and bioactive content. Quantitative analysis of total phenol, flavonoid and anthocyanin content were performed using spectrophotometry and UPLC-DAD-ESI-MS/MS. Optimum conditions were determined as 600 W, 100% ethanol, 12 min for butyrylcholinesterase inhibitory and 800 W, 50% ethanol, 4 min for tyrosinase inhibitory activity. Microwave extraction outperformed conventional solvent extracts (hexane, dichloromethane, 2-methyl tetrahydrofuran, ethanol, 70% ethanol and water) in terms of activity and content. The isolated fraction containing major anthocyanins as cyanidin-3-sophoroside-5-glucoside and cyanidin-3-(sinapoyl)-sophoroside-5-glucoside was identified as the responsible portion for tyrosinase inhibitory activity. The dominant anthocyanins rich fraction of the optimum microwave extract can be considered for the production of antityrosinase products, while the identification of inhibitor metabolites for acetylcholinesterase and butyrylcholinesterase can be targeted for future studies considering red cabbage as a valuable source.

Anticholinesterase Compounds from Endemic Prangos uechtritzii.

In this study, the anticholinesterase effects of the extracts and isolated compounds from the roots of endemic Prangos uechtritzii Boiss & Hausskn (Apiaceae) are reported. A novel polyacetylenic compound; (+)-8-O-methyloplopantriol A along with two known polyacetylenes; (-)-panaxynol, (+)-falcarindiol and fifteen known coumarin derivatives; umbelliferone, 6-formylumbelliferone, suberosin, 7-demethylsuberosin, (+)-ulopterol, tamarin, psoralen, imperatorin, (+)-oxypeucedanin, (+)-oxypeucedanin hydrate, (+)-oxypeucedanin methanolate, (+)-marmesin, (-)-prantschimgin, (+)-decursinol, and (-)-adicardin were isolated from the hexane (Pu-HE), chloroform (Pu-CE), and methanol (Pu-ME) extracts of P. uechtritzii roots. (-)-Panaxynol, (+)-falcarindiol, 6-formylumbelliferone, (+)-decursinol, and (-)-adicardin were obtained from the genus Prangos for the first time. (+)-8-O-Methyloplopantriol A inhibited both AChE (IC50 =194.5±5.8 µM) and BChE (IC50 =51.9±2.96 µM) enzymes. (+)-Falcarindiol, 6-formylumbelliferone, 7-demethylsuberosin, tamarin, and imperatorin also exhibited BChE-specific inhibitory activities (IC50 =27.88-93.86 µM). (+)-Falcarindiol (IC50 =27.88±0.91 µM) and imperatorin (IC50 =30.89±1.40 µM) as the most active components could be led compounds to develop new BChE inhibitors with further research against Alzheimer's disease.

Forecasting COVID19 Reliability of the Countries by Using Non-Homogeneous Poisson Process Models.

Reliability is the probability that a system or a product fulfills its intended function without failure over a period of time and it is generally used to determine the reliability, release and testing stop time of the system. The primary objective of this study is to predict and forecast COVID19 reliabilities of the countries by utilizing this definition of the reliability. To our knowledge, this study is the first carried out in the direction of this objective. The major contribution of this study is to model the COVID19 data by considering the intensity functions with different types of functional shapes, including geometric, exponential, Weibull, gamma and identifying best fit (BF) model for each country, separately. To achieve the objective determined, cumulative number of confirmed cases are modelled by eight Non-Homogenous Poisson Process (NHPP) models. BF models are selected based on three comparison criteria, including Root Mean Square Error (RMSE), Normalized Root Mean Square Error (NRMSE), and Theil Statistics (TS). The results can be summarized as follows: S-shaped models provide better fit for 56 of 70 countries. Current outbreak may continue in 43 countries and a new outbreak may occur in 27 countries. 50 countries have the reliability smaller than 75%, 9 countries between 75% and 90%, and 11 countries a 90% or higher on 11 August 2021. Supplementary Information: The online version contains supplementary material available at 10.1007/s00354-022-00183-1.

Surgical treatment of a difficult case of atrial tachycardia requiring multiple electrophysiologic procedures.

A 34-year-old male with incessant drug-refractory atrial tachycardia (AT) was referred to our clinic for catheter ablation. The procedure began with endocardial activation mapping. The earliest endocardial activation site was in the right atrial appendage (RAA). The procedure continued with mapping of the left atrium through a transseptal approach. The earliest local activation was recorded at the anterior site of the right pulmonary veins. Radiofrequency (RF) ablation of both localizations was performed synchronously but failed to terminate the arrhythmia. The procedure continued with isolation of the RAA using cryoballoon but failed again due to the anomalous structure of the RAA. Then, epicardial RF ablation was attempted but failed. Finally, AT could only be terminated by surgical excision of the RAA.

Comparative evaluation of relaxant effects of three prangos species on mouse corpus cavernosum: Chemical characterization and the relaxant mechanisms of action of P. pabularia and (+)-oxypeucedanin.

ETHNOPHARMACOLOGICAL RELEVANCE: Erectile dysfunction (ED) is the most common form of sexual dysfunction which has been the topic of great interest through the history by all cultures. It is now among the most treated health problems in men of all ages that develop under the influence of lifestyle factors and some diseases. Plants are extensively used to cure sexual dysfunction for centuries. Roots of Prangos sp. have been used to improve sexual performance in Anatolian traditional medicine and are rich of coumarin, furanocoumarin and their derivatives. Scientific research is necessary to support and validate the ethno-traditional uses of these plants. AIM OF THE STUDY: The aim of this study is to investigate the effects of the root extracts of P. pabularia, P. uechtritzii and P. heyniae on erectile function and to isolate and identify the chemical compounds of the most active extract and reveal possible pharmacological mechanism of the major compound of the extract with the strongest relaxant effect in mouse corpus cavernosum (MCC). MATERIALS AND METHODS: The roots of plants were extracted with chloroform, n-hexane and methanol. The compounds were isolated from the extract by column chromatography and structures were identified by NMR and MS. The relaxant effects of extracts (10-7-10-4 g/mL), (+)-oxypeucedanin (10-7-10-4 M) and Na2S (10-7-3 × 10-3 M) were tested in MCC strips by DMT myograph. To investigate the mechanism, the synthesis inhibitors of aminooxyacetic acid (AOAA, 10-2 M) and nitro-L-arginine methyl ester (L-NAME, 10-4 M) were used, respectively. H2S formation was evaluated basal and L-cysteine (L-cyst)-stimulated conditions by H2S microsensor. RESULTS: All extracts relaxed MCC in a concentration dependent manner. The maximum relaxing effects were achieved with chloroform extracts. Chloroform extract of P. pabularia (Pp-CE) was more potent than the others. Pp-CE-induced relaxations were significantly decreased by AOAA and L-NAME. (+)-Oxypeucedanin, the major compound of Pp-CE, induced relaxant responses and this effect was inhibited by AOAA, but not L-NAME. The relaxation of (+)-oxypeucedanin was found to be similar in view of Emax to positive control H2S donor Na2S. (+)-Oxypeucedanin increased L-cyst-stimulated H2S formation. Augmentation of H2S synthesis with (+)-oxypeucedanin was inhibited by AOAA. CONCLUSIONS: Pp-CE has the strongest effect on relaxation of MCC and this result supports the traditional aphrodisiac use of P. pabularia root extract in Anatolia. The pharmacological mechanisms of Pp-CE to relax MCC involve NO and H2S formation. (+)-Oxypeucedanin could be responsible for the H2S-mediated relaxations of Pp-CE in MCC.

Predictors of positive response to beta-blockers for treatment of premature ventricular complexes.

BACKGROUND: The aim of the present study is to investigate the possible factors that might be predictive of effective antiarrhythmic effect of beta-blockers on premature ventricular complexes (PVC). METHODS: Data of 190 eligible consecutive patients to whom beta-blocker therapy had been initiated for treatment of PVC's were retrospectively evaluated. The Holter recording acquired before beta-blocker initiation and the first Holter acquired after beta blocker initiation during follow up was comprehensively evaluated for each patient. Parameters obtained from pre- and post-beta-blocker 24 h Holter recordings were compared with each other and possible predictors were evaluated for positive response to beta-blocker therapy. RESULTS: Sixty-one patients (32.1%) were observed to respond beta-blocker therapy with at least 50% reduction of daily PVC burden. Patients who responded to beta-blockers had significantly higher ratio of patients who had positive correlation between hourly heart rate and corresponding hourly PVC number (fast HR-PVC status) compared with non-responders (73.8% vs 48.1%, p < 0.001). Binary logistic regression analysis revealed PVC QRS width (Odds ratio: 0.971; p: 0.037) and fast HR-PVC status (Odds ratio: 2.935; p: 0.007) as the independent predictors of positive response to beta-blockers for treatment of PVC. CONCLUSION: Positive correlation between hourly heart rate and PVC incidence was found to be independent positive predictor and PVC QRS width was found to be independent negative predictor of beta-blocker success in our study. This observation might have important clinical implications to guide medical treatment of PVCs in clinical practice.

Antimicrobial effect of natural kinds of toothpaste on oral pathogenic bacteria.

INTRODUCTION: Because of the adverse effects on human health of some antimicrobial ingredients in traditional toothpaste, consumers are increasingly turning to toothpastes with natural ingredients. This study evaluates the antimicrobial effect of toothpastes containing different natural active agents against three oral pathogens: Streptococcus mutans, Streptococcus sanguinis, and Enterococcus faecalis. METHODOLOGY: This study tested one traditional toothpaste and seven different natural toothpastes containing theobromine, aloe vera, miswak, propolis, chitosan, enzymes and probiotics. The agar-well diffusion method was used to test the antimicrobial effect. Inhibition zones formed around toothpastes after 24 hours of incubation were measured and the data collected were statistically analyzed. RESULTS: Toothpastes containing theobromine and chitosan and the traditional toothpaste showed antimicrobial efficacy for all tested bacteria. Toothpastes containing aloe vera, miswak, and propolis were only effective on S. mutans, while toothpastes containing probiotics and enzymes did not show any antimicrobial effect on the bacteria. Among toothpastes with natural ingredients, the theobromine-containing toothpaste showed the highest efficacy on S. mutans, while the aloe vera- and propolis-containing toothpastes had the lowest efficacy (p < 0.05). CONCLUSIONS: Theobromine- and chitosan-containing toothpastes, which showed antimicrobial activity against all bacteria, can be recommended as alternatives to traditional toothpastes.

Bidirectional ventricular tachycardia induced by respiratory alkalosis mediated hypokalemia in a patient with acute ischemic heart failure.

Bidirectional ventricular tachycardia (BVT) is a rare arrhythmia that is generally observed in patients with catecholaminergic ventricular tachycardia or digoxin overdose. Herein, we present a case of BVT and electrical storm (ES) in an acute ischemic heart failure patient that is typically induced by hypokalemia. The patient was in invasive mechanical ventilator (MV) support and hypokalemia was related to acute respiratory alkalosis and that caused refractory hypokalemia despite intravenous (IV) potassium replacement. We also discuss our approach to solve refractory hypokalemia caused by respiratory alkalosis.

Evaluation of acute alterations in electrocardiographic parameters after cryoballoon ablation of atrial fibrillation and possible association with recurrence.

OBJECTIVE: This study aimed to evaluate the acute effect of cryoballoon ablation (CB-A) on electrocardiographic parameters that have been suggested to reflect heterogeneity in atrial conduction and ventricular repolarization. METHODS: A total of 67 patients (52.6±13.2 years, 43 men) without any exclusion criteria who had undergone CB-A for atrial fibrillation (AF) between January 01, 2015, and December 31, 2018, constituted our study population. Electrographic recordings obtained before and after the ablation procedure on the same day were retrospectively evaluated for the P-wave dispersion, QTc dispersion, Tp-Te interval, and Tp-Te/QT ratio. The pre- and post-ablation values were tested for significant differences. The association of the possible CB-A-related changes in these parameters with AF recurrence during follow-up was evaluated. RESULTS: P dispersion (30.1±6.8 vs. 35.9±9.4 ms, p<0.001), QT dispersion (20.7±7.5 vs. 24.0±8.8 ms, p<0.001), Tp-Te duration (on V5 83.6±8.1 vs. 110.2±9.5 ms, p<0.001), and Tp-Te/QT ratio (on V5 0.22±0.03 vs. 0.28±0.02, p<0.001) were observed to increase significantly after CB-A. There was no association between the magnitudes of change in any parameter and AF recurrence. CONCLUSION: CB-A had significant effects on electrocardiographic parameters related to atrial conduction and ventricular repolarization in the acute phase after CB-A. Further prospective studies are required to examine the time-related course of these alterations and their impact on clinical outcomes.

Speckle-tracking echocardiography can predict atrial fibrillation in patients with supraventricular tachycardia.

PURPOSE: Atrioventricular nodal reentry tachycardia (AVNRT) is the most common supraventriculer arrhythmia in daily clinical practice. Comorbidity of AVNRT and atrial fibrillation (AF) has been well documented in some patients and AF development has been observed more frequently in AVNRT patients during their long-term follow-up. This study was conducted in order to investigate the left atrial two-dimensional-speckle-tracking echocardiographic (STE) parametres as the predictors of the occurence of AF in long-term follow-up in patients with spontaneously developed AF during AVNRT ablation. METHODS: Two hundred and thirty two consecutive AVNRT patients who developed spontaneous AF during ablation procedure were included in the study. The patients were followed up for a mean follow-up period of 6.2 ± 2.1 years. All patients were evaluated using the 2D-STE method. AF was developed in 34 patients during the follow-up period. Cox regression analysis was performed in order to identify the independent predictors of AF occurence. RESULTS: Left atrial LA-res, LA-pump, LA-SRs, LA-SRe, and LA-SRa values were found to be significantly decreased in the group of patients that developed AF during the follow-up period (p < .001 for all aforementioned values). Multivariate cox regression analysis revealed that LA-res (hazard ratio [HR], 0.367; 95% confidence interval [CI], 0.161-0.0.683, p < .001) and SRe (HR, 0.472; 95% CI, 0.346-0.825, p = .006) were independent risk factors associated with the occurrence of AF. CONCLUSION: In conclusion, it was demonstrated for the first time with this study that 2D-STE can effectively predict the development of AF in long-term follow-up in patients with spontaneously developed AF during AVNRT ablation.

Predictors of adequate intraprocedural premature ventricular complex (PVC) frequency during idiopathic PVC ablation.

BACKGROUND: The aim of the present study was to determine the predictors of adequate intraprocedural premature ventricular complex (PVC) frequency for successful mapping and ablation of idiopathic PVCs. METHODS: A total of 101 consecutive patients (45 men; age: 47.9 ± 14.2 years) who had undergone idiopathic PVC ablation between 01 November 2018 and 24 June 2020 constituted our study population. Clinical and demographic data, procedural details and 24 h rhythm recordings that had been recorded before the procedure were retrospectively evaluated. Total PVC burden and diurnal variability assessed by the ratio of night time (22:00-06:00) over day time (06:00-22:00) PVC burden was calculated. The relationship between hourly PVC number and heart rate was also evaluated for each patient. Clinical characteristics and Holter parameters were compared between groups with and without adequate intraprocedural frequency of PVCs that permitted activation mapping. RESULTS: In all, 27 patients (26.7%) had infrequent intraprocedural PVCs which necessitated isoproterenol infusion or cancellation of ablation procedure due to inability of activation mapping. PVC burden was significantly higher in the group with frequent intraprocedural PVCs (26.1 ± 9.4% vs 21.2 ± 10.3%; p: 0.026). There were no significant differences between groups regarding the relationship between hourly PVC number and heart rate or the ratio of night/day PVC burden. Binary logistic regression analysis revealed the 24 h Holter PVC burden as the sole parameter that is significant predictor of frequent intraprocedural PVCs permitting activation mapping. CONCLUSION: The 24 h PVC burden was the only predictor of adequate intraprocedural PVC frequency permitting activation mapping during idiopathic PVC ablation.

Tp-Te interval and Tp-Te/QT ratio may be predictive of idiopathic ventricular tachycardia in patients with frequent outflow tract premature ventricular complexes.

BACKGROUND: The aim of present study is to evaluate the predictive value of QTc dispersion, Tp-Te interval and Tp-Te/QT ratio for idiopathic monomorphic outflow tract ventricular tachycardia (VT) occurrence in patients with frequent idiopathic outflow tract premature ventricular complexes (PVCs). METHODS: A total of 180 patients (49.2 ± 13.6 years, 74 male) who had undergone outflow tract PVC ablation between 01 January 2015 and 01 November 2018 constituted our study population. Patients with isolated outflow tract PVC without any VT recording on Holter recordings and without any inducible VT at EPS were classified as isolated PVC group. Patients with any episode of VT that has the same morphology with outflow tract PVC were classified as nonsustained or sustained VT groups based on the duration of VT episode. QTc dispersion, Tp-Te and Tp-Te/QT ratio values were calculated and compared between groups. RESULTS: There were 116 patients with isolated PVC, 35 patients with nonsustained VT and 29 patients with sustained VT. QTc dispersion, Tp-Te and Tp-Te/QT ratio values were significantly lower in patients with isolated PVC compared to patients with nonsustained or sustained VT episodes. Tpeak to Tend interval greater than 110.5 msec on derivation V6 predicted VT occurrence with 93.8% sensitivity and 82.8% specificity. Tpeak to Tend/QT interval greater than 0.27 on derivation V6 predicted VT occurrence with 93.8% sensitivity and 0.81% specificity. CONCLUSION: Tp-Te interval and Tp-Te/QT ratio on derivation V6 may aid in prediction of presence of outflow tract VT in clinical practice.

Acute effect of outflow tract premature ventricular complex ablation on QT dispersion, Tp-e interval and Tp-e/QT ratio.

BACKGROUND: There is limited data regarding the effect of idiopathic premature ventricular complexes (PVC) on myocardial repolarisation. Most of PVC's originate from right and left ventricular outflow tracts (RVOT and LVOT). AIM: The aim of this study is to evaluate the acute effect of outflow tract PVC ablation on electrocardiographic repolarisation markers. METHODS: A total of 180 patients (49.2 ± 13.6 years, 74 male) without any exclusion criteria who had undergone outflow tract PVC ablation between 1 January 2015 and 1 November 2018 constituted our study population. Electrocardiographic recordings that had been obtained before and after ablation procedure on the same day were retrospectively evaluated for the QTc dispersion, Tp-e interval, Tp-e/QT ratio and Tp-e/QTc ratio. Significance of difference between pre- and postablation values was tested. RESULTS: There was no significant difference regarding QTc dispersion between pre- and post-ablation state (36.5 ± 20.9 vs. 35.3 ± 16.4 ms, p: NS). However, Tp-e and Tp-e/QT values in all lateral precordial derivations were observed to decrease significantly after PVC ablation (in the respective order on derivation V5: 104.0 ± 21.6 ms vs. 91.1 ± 14.8 ms, p<.001 and 0.26 ± 0.05 vs. 0.23 ± 0.04, p<.001). CONCLUSIONS: Based on these observations, it may be suggested that frequent outflow tract PVC's increase transmural dispersion of repolarisation and this effect is attenuated by catheter ablation in the acute phase. Results of further prospective studies are required for evaluation of the long term effects of PVC ablation on myocardial repolarisation.

Transvenous extraction of pacemaker leads via femoral approach using a gooseneck snare.

BACKGROUND: The growing problem of endocardial lead infections and lead malfunctions has increased interest in percutaneous lead-removal technology. Transvenous lead extraction (TLE) via simple manual traction (SMT) is the first-line therapy. When SMT is not successful, TLE from the femoral vein using a gooseneck snare (GS) with a radiofrequency ablation catheter (RFAC) may be an alternative option. The aim of our study was to evaluate the success rate of transvenous extraction of chronically implanted leads via the femoral approach using a GS with RFCA in cases of failure with SMT. METHODS: The study included 94 consecutive patients who were referred for lead extraction due to pocket erosion and infection (71 patients) and to lead malfunction (23 patients). Initially, SMT was attempted for all patients. If SMT was not successful, patients underwent TLE using a GS with RFAC. RESULTS: Leads were extracted successfully with SMT in 34 patients (54 leads), while 60 patients (83 leads) underwent TLE using a GS with RFAC. The mean indwelling time of the leads was longer in the femoral approach with GS (87.5 ± 37.9 vs. 31.3 ± 25.8 months; p < 0.001). The procedural success rate was 96.7% in the femoral approach with GS. A preceding implantation lead duration of >51 months predicted an unsuccessful SMT necessitating alternative TLE using a GS with RFAC with 86% sensitivity and 78% specificity (p < 0.001). CONCLUSION: Transvenous lead extraction via the femoral approach using GS with RFAC may be an alternative approach to SMT with a high success rate, especially when the indwelling time of the leads is long.

Fluoroscopy time and scattered radiation during electrophysiology procedures: analysis of one-year data of a laboratory providing electrophysiology training.

OBJECTIVES: Patients and medical staff expose to significant radiation during electro-physiological (EP) procedures. There are few data regarding the leading factors of longer fluoroscopy time and higher scattered radiation in a laboratory giving EP training during those interventions. MATERIAL AND METHODS: The patients' recordings that underwent EP procedure in a single centre arrhythmia unit from February 2019 to January 2020 were examined. Prospectively collected data regarding procedure duration, fluoroscopy time and total air kerma, demographic characteristics of the patients, type of procedure, success of ablation and the use of electro anatomic mapping were retrospectively evaluated. Predictors of total air kerma were analysed with linear regression analysis. RESULTS: Study population consisted of 437 patients with a median age of 47 (39-56); 184 (42.1%) were male. Median fluoroscopy time was 768 (420-1320) seconds and median cumulative air kerma was 369 (191-750) mGy. Fluoroscopy time and cumulative air kerma were significantly lower in diagnostic EP studies compared to other procedures. There was no difference in terms of total air kerma between the procedures other than the diagnostic EP study. In multivariable linear regression analysis; body surface area, fluoroscopy time, not using the electro-anatomical mapping, unsuccessful ablation and atrial flutter ablation were predictors of total air kerma in EP studies performed by trainees. CONCLUSION: Scattered radiation during EP procedures performed by in-training operators is related with some factors. Awareness about those may help to effort reducing the harmful effect of ionising radiation.

The effect of P wave indices on new onset atrial fibrillation after trans-catheter aortic valve replacement.

OBJECTIVES: Data is scarce regarding the relation between P wave indices and new onset atrial fibrillation (NOAF) after trans-catheter aortic valve replacement (TAVR). AIMS: The present study aimed to find out certain characteristics of P wave that may predict NOAF after TAVR procedure. METHOD: Patients with severe calcific aortic stenosis who had undergone TAVR procedure between 2013 and 2019 in two centers were investigated. P wave abnormalities that have been resumed to reflect impaired atrial conduction; partial and advanced inter atrial block (IAB), P-wave terminal force in lead V1, P wave dispersion, reduced amplitude of P- wave in lead I, P wave peak time in D2 and V1 were evaluated on pre- procedural 12 derivation surface electrocardiography (ECG). The relationship between these parameters and incidence of NOAF during index hospitalization was evaluated. RESULTS: A total of 227 consecutive patients (median age 79 [74-83]; 134 [59%] female) were included in the study. NOAF occurred in 46 (20.3%) patients. P wave duration, P wave dispersion, number of patients with partial and advanced IAB, left atrium diameter, STS score were higher in NOAF patients. Use of general anesthesia and history of prior open heart surgery were also more frequent in NOAF group. In multivariable logistic regression analysis; advanced IAB (OR 6.413 [2.555-16.095] p < 0.01), P wave dispersion (OR 3.544 [1.431-8.780] p = 0.006) and use of general anesthesia (OR 2.736 [1.225-6.109] p = 0.014) were independent predictors of NOAF. CONCLUSION: Among P wave abnormalities evaluated on pre-procedural 12-derivation surface ECG, advanced IAB and P wave dispersion may predict NOAF after TAVR procedure.

Electrocardiographic Ccharacteristics of metastatic cardiac tumors presenting with ST-segment elevation.

INTRODUCTION: ST segment elevation (STE) in the standard 12­lead surface electrocardiography (ECG) is a well-known finding in patients with metastatic cardiac tumors. It is important to identify the specific characteristics of STE among those patients to prevent unnecessary aggressive treatments. In the present study, we aimed to demonstrate the ECG characteristics of patients with metastatic cardiac tumors who has STE. MATERIAL AND METHODS: Medical literature was searched from Pubmed database with key words "metastatic cardiac tumors" or "cardiac tumors" and "ST segment elevation" or "ST elevation". In addition, remaining articles were explored using the references of case reports which were obtained during former screening (snowball procedure). RESULTS: Thirty six of 46 case reports were included and ECG characteristics of each case were evaluated. Convex- shaped STE was observed in all patients and it showed a specific coronary territory in 35 of 36 patients (97.2%). Pathologic Q wave and/or loss of R wave progression were observed in only one patient. T wave inversion following STE was detected in 34 patients (94.4%). STE evolution was absent in 32 of 36 patients while the information regarding STE evolution were not provided in the remaining cases. CONCLUSION: STE due to tumor invasion has certain characteristics which could help clinicians in the differential diagnosis.