Results from a real-time dosimetry study during left atrial ablations performed with ultra-low dose radiation settings

Background: Three-dimensional mapping systems and the use of ultra-low dose radiation protocols have supported minimization of radiation dose during left atrial ablation procedures. By using optimal shielding, scattered radiation reaching the operator can be further reduced. This prospective study was designed to determine the remaining operator radiation exposure during left atrial catheter ablations using real-time dosimetry. Methods: Radiation dose was recorded using real-time digital dosimetry badges outside the lead apron during 201 consecutive left atrial fibrillation ablation procedures. All procedures were performed using the same X‑ray system (Siemens Healthineers Artis dBc; Siemens Healthcare AG, Erlangen, Germany) programmed with ultra-low dose radiation settings including a low frame rate (two frames per second), maximum copper filtration, and an optimized detector dose. To reduce scattered radiation to the operators, table-suspended lead curtains, ceiling-suspended leaded plastic shields, and radiation-absorbing shields on the patient were positioned in an overlapping configuration. Results: The 201 procedures included 139 (69%) pulmonary vein isolations (PVI) (20 cryoballoon ablations, 119 radiofrequency ablations, with 35 cases receiving additional ablation of the cavotricuspid isthmus) and 62 (31%) PVI plus further left atrial substrate ablation. Mean radiation dose measured as dose area product for all procedures was 128.09 ± 187.87 cGy ∙ cm2 with a mean fluoroscopy duration of 9.4 ± 8.7 min. Real-time dosimetry showed very low average operator doses of 0.52 ± 0.10 µSv. A subanalysis of 51 (25%) procedures showed that the radiation burden for the operator was highest during pulmonary vein angiography. Conclusion: The use of ultra-low dose radiation protocols in combination with optimized shielding results in extremely low scattered radiation reaching the operator.Hintergrund: Der Einsatz von dreidimensionalen Mapping-Systemen und von Niedrigdosiseinstellungen der Röntgenanlage führte zu einer Minimierung der Strahlenbelastung bei linksatrialen Ablationen. Optimierte Abschirmung kann die Streustrahlung als Strahlenbelastung des Untersuchers weiter reduzieren. In dieser prospektiven Studie wurde untersucht, welcher Strahlenbelastung der Untersucher unter Anwendung dieser Maßnahmen während linksatrialer Ablationen noch ausgesetzt ist. Methoden: Die Strahlenbelastung wurde mittels Echtzeitdosimetrie an der Außenseite der Bleischürze während 201 konsekutiven linksatrialen Ablationen gemessen. Alle Prozeduren wurden mit demselben Röntgensystem (Siemens Healthineers Artis dBc; Siemens Healthcare AG, Erlangen, Deutschland) und mit strahlensparenden Einstellungen durchgeführt, unter anderem mit einer niedrigen Bildrate von 2 Bildern/s, maximaler Kupferfilterung und angepasster Detektoreingangsdosis. Um Streustrahlung zu reduzieren, wurden die Seitenlamellen, die mobile Acrylscheibe und die strahlenabsorbierenden Schilde auf dem Patienten überlappend angeordnet. Ergebnisse: Die 201 Prozeduren umfassten 139 (69%) Pulmonalvenenisolationen (PVI; 20 Kryoballonablationen, 119 Radiofrequenzablationen, in 35 Fällen mit zusätzlicher Ablation des kavotrikuspidalen Isthmus) und 62 (31%) PVI mit zusätzlicher linksatrialer Substratmodifikation. Die Strahlendosis als Dosis-Flächen-Produkt (DAP) betrug durchschnittlich 128,09± 187,87 cGy ⋅cm2 bei einer Fluoroskopiedauer von imMittel 9,4± 8,7min. Die per Echtzeitdosimetrie erhobene mittlere Strahlendosis des Untersuchers zeigte sich mit 0,52± 0,10 μSv als sehr gering. Eine Subanalyse bei 51 (25 %) Prozeduren zeigte, dass die Strahlendosis des Untersuchers während der Pulmonalvenenangiographie am höchsten war. Schlussfolgerung: Die Kombination von Niedrigdosiseinstellungen und optimierter Abschirmung führt zu einer extremniedrigen Streustrahlung als Strahlenbelastung des Untersuchers

Implantable loop recorders in patients with unexplained syncope: Clinical predictors of pacemaker implantation

Background: Implantable loop recorders (ILR) are a valuable tool for the investigation of unexplained syncopal episodes. The aim of this retrospective single center study was to identify predictive factors for pacemaker implantation in patients with unexplained syncope who underwent ILR insertion. Methods: One hundred six patients were retrospectively analyzed (mean age 59.1 years; 47.2% male) with unexplained syncope and negative conventional testing who underwent ILR implantation. The pri- mary study endpoint was detection of symptomatic or asymptomatic bradycardia requiring pacemaker implantation.  Results: The average follow-up period after ILR implantation was 20 ± 15 months. Pacemaker im- plantation according to current guidelines was necessary in 22 (20.8%) patients, mean duration until index bradycardia was 81 ± 88 (2–350) days. Ten (45.5%) patients received a pacemaker due to sinus arrest, 7 (31.8%) patients due to third-degree atrioventricular block, 2 (9.1%) patients due to second- degree atrioventricular block and 1 (4.5%) patient due to atrial fibrillation with a slow ventricular rate. Three factors remained significant in multivariate analysis: obesity, which defined by a body mass index above 30 kg/m2 (OR: 7.39, p = 0.014), a right bundle branch block (OR: 9.40, p = 0.023) and chronic renal failure as defined by a glomerular filtration rate of less than 60 mL/min (OR: 6.42, p = 0.035). Conclusions: Bradycardia is a frequent finding in patients undergoing ILR implantation due to un- explained syncope. Obesity, right bundle branch block and chronic renal failure are independent clinical predictors of pacemaker implantation

a prospective cohort study

Background The effects of target temperature management (TTM) on the heart aren’t thoroughly studied yet. Several studies showed the prolongation of various ECG parameters including Tpeak-Tend-time under TTM. Our study’s goal is to evaluate the acute and long-term outcome of these prolongations. Methods In this study we included patients with successful resuscitation after cardiac arrest who were admitted to the Charité Virchow Klinikum Berlin or the Heart and Vascular Centre of the Ruhr University Bochum between February 2006 and July 2013 (Berlin) or May 2014 to November 2015 (Bochum). For analysis, one ECG during TTM was recorded after reaching the target temperature (33–34 °C) or in the first 6 h of TTM. If possible, another ECG was taken after TTM. The patients were being followed until February 2016. Primary endpoint was ventricular arrhythmia during TTM, secondary endpoints were death and hospitalization due to cardiovascular diseases during follow-up. Results One hundred fifty-eight patients were successfully resuscitated in the study period of which 95 patients had usable data (e.g. ECGs without artifacts). During TTM significant changes for different parameters of ventricular de- and repolarization were noted: QRS (103.2 ± 23.7 vs. 95.3 ± 18.1; p = 0.003),QT (405.8 ± 76.4 vs. 373.8 ± 75.0; p = 0.01), QTc (474.9 ± 59.7 vs. 431.0 ± 56.8; p < 0.001), JT (302.8 ± 69.4 vs. 278.5 ± 75.2; p = 0.043), JTc (354.3 ± 60.2 vs. 318.7 ± 59.1; p = 0.001). 13.7% of the patients had ventricular arrhythmias during TTM, however these patients showed no difference regarding their ECG parameters in comparison to those were no ventricular arrhythmias occurred. We were able to follow 69 Patients over an average period of 35 ± 31 months. The 14 (21.5%) patients who died during the follow-up had significant prolongations of the TpTe-time in the ECGs without TTM (103.9 ± 47.2 vs. 75.8 ± 28.6; p = 0.023). Conclusion Our results show a significant prolongation of ventricular repolarization during TH. However, there was no significant difference between the ECG parameters of those who developed a ventricular arrhythmia and those who did not. The temporary prolongation of the repolarization during TTM seems to be less important for the prognosis of the patient. Whereas the prolongation of the repolarization in the basal ECG is associated with a higher mortality in our study

Safe procedures despite ultra low radiation doses during catheter ablations of atrial and ventricular arrhythmias—A multicenter experience

Introduction: Despite the development of non-fluoroscopic catheter visualization options, fluoroscopy is still used in most ablation procedures. The aim of this multicenter study was to evaluate the safety and efficacy of a new ultra-low dose radiation protocol for EP procedures in a large number of patients. Methods and results: A total of 3462 consecutive patients (male 1926 (55.6%), age 64.4 ± 14.0 years, BMI 26.65 ± 4.70) undergoing radiofrequency ablation (left atrial (n = 2316 [66.9%], right atrial (n = 675 [19.5%], or ventricular (n = 471 [13.6%]) in three German centers were included in the analysis. Procedures were performed using a new ultra-low dose protocol operating at 8nGy for fluoroscopy and 36nGy for cine-loops. Additionally a very low framerate (2-3FPS) was used. Using the new protocol very low Air kerma-area product (KAP) values were achieved for left atrial ablations (104.25 ± 84.22 μGym2 ), right atrial ablations (70.98 ± 94.79 μGym2 ) and ablations for ventricular tachycardias or PVCs (78.62 ± 66.59 μGym2 ). Acute procedural success was achieved in 3289/3388 (97.1%) while the rate of major complications was very low compared to previously published studies not using low dose settings (n = 20, 0.6%). Conclusion: The ultra-low dose, low framerate protocol leads to very low radiation doses for all EP procedures while neither procedural time, fluoroscopy time nor success or complication rates were compromised. When compared to current real-world Air KAP data the new ultra-low dose fluoroscopy protocol reduces radiation exposure by more than 90%

Lipid-lowering for lower limb atherosclerosis

Background: Lipid-lowering therapy is recommended for secondary prevention in people with coronary artery disease. It may also reduce cardiovascular events and/or local disease progression in people with lower limb peripheral arterial disease (PAD). Objectives: To assess the effects of lipid-lowering therapy on all-cause mortality, cardiovascular events and local disease progression in patients with PAD of the lower limb. Search methods: The authors searched The Cochrane Peripheral Vascular Diseases Group's Specialised Register (last searched February 2007) and the Cochrane Central Register of Controlled Trials (CENTRAL) (last searched Issue 2, 2007) for publications describing randomised controlled trials of lipid-lowering therapy in peripheral arterial disease of the lower limb. Selection criteria: Randomised controlled trials of lipid-lowering therapy in patients with PAD of the lower limb. Data collection and analysis: Three authors independently assessed trial quality and extracted data. Main results: Eighteen trials were included, involving a total of 10,049 participants. Trials differed considerably in their inclusion criteria, outcomes measured, and type of lipid-lowering therapy used. Only one trial (PQRST) reported a detrimental effect of active treatment on blood lipid/lipoprotein levels. The pooled results from all eligible trials indicated that lipid-lowering therapy had no statistically significant effect on overall mortality (Odds Ratio (OR) 0.86; 95% Confidence Interval (CI) 0.49 to 1.50) or on total cardiovascular events (OR 0.8; 95% CI 0.59 to 1.09). However, subgroup analysis which excluded PQRST showed that lipid-lowering therapy significantly reduced the risk of total cardiovascular events (OR 0.74; CI 0.55 to 0.98). This was primarily due to a positive effect on total coronary events (OR 0.76; 95% CI 0.67 to 0.87). Greatest evidence of effectiveness came from the use of simvastatin in people with a blood cholesterol &ge; 3.5 mmol/litre (HPS). Pooling of the results from several small trials on a range of different lipid-lowering agents indicated an improvement in total walking distance (Mean Difference (MD) 152 m; 95% CI 32.11 to 271.88) and pain-free walking distance (WMD 89.76 m; 95% CI 30.05 to 149.47) but no significant impact on ankle brachial index (WMD 0.04; 95% CI -0.01 to 0.09). Authors' conclusions: Lipid-lowering therapy is effective in reducing cardiovascular mortality and morbidity in people with PAD. It may also improve local symptoms. Until further evidence on the relative effectiveness of different lipid-lowering agents is available, use of a statin in people with PAD and a blood cholesterol level &ge; 3.5 mmol/litre is most indicated.Output Type: Revie

Missense Variant E1295K of Sodium Channel SCN5A Associated With Recurrent Ventricular Fibrillation and Myocardial Inflammation

SCN5A was considered an exclusively cardiac expressed ion channel but discovered to also act as a novel innate immune sensor. We report on a young SCN5A variant carrier with recurrent ventricular fibrillation and massive myocardial inflammation whose peculiar clinical course is highly suggestive of such a dual role of SCN5A. (Level of Difficulty: Advanced.

Hypothermia induced alteration of repolarization - impact on acute and long-term outcome: a prospective cohort study

Abstract Background The effects of target temperature management (TTM) on the heart aren’t thoroughly studied yet. Several studies showed the prolongation of various ECG parameters including Tpeak-Tend-time under TTM. Our study’s goal is to evaluate the acute and long-term outcome of these prolongations. Methods In this study we included patients with successful resuscitation after cardiac arrest who were admitted to the Charité Virchow Klinikum Berlin or the Heart and Vascular Centre of the Ruhr University Bochum between February 2006 and July 2013 (Berlin) or May 2014 to November 2015 (Bochum). For analysis, one ECG during TTM was recorded after reaching the target temperature (33–34 °C) or in the first 6 h of TTM. If possible, another ECG was taken after TTM. The patients were being followed until February 2016. Primary endpoint was ventricular arrhythmia during TTM, secondary endpoints were death and hospitalization due to cardiovascular diseases during follow-up. Results One hundred fifty-eight patients were successfully resuscitated in the study period of which 95 patients had usable data (e.g. ECGs without artifacts). During TTM significant changes for different parameters of ventricular de- and repolarization were noted: QRS (103.2 ± 23.7 vs. 95.3 ± 18.1; p = 0.003),QT (405.8 ± 76.4 vs. 373.8 ± 75.0; p = 0.01), QTc (474.9 ± 59.7 vs. 431.0 ± 56.8; p < 0.001), JT (302.8 ± 69.4 vs. 278.5 ± 75.2; p = 0.043), JTc (354.3 ± 60.2 vs. 318.7 ± 59.1; p = 0.001). 13.7% of the patients had ventricular arrhythmias during TTM, however these patients showed no difference regarding their ECG parameters in comparison to those were no ventricular arrhythmias occurred. We were able to follow 69 Patients over an average period of 35 ± 31 months. The 14 (21.5%) patients who died during the follow-up had significant prolongations of the TpTe-time in the ECGs without TTM (103.9 ± 47.2 vs. 75.8 ± 28.6; p = 0.023). Conclusion Our results show a significant prolongation of ventricular repolarization during TH. However, there was no significant difference between the ECG parameters of those who developed a ventricular arrhythmia and those who did not. The temporary prolongation of the repolarization during TTM seems to be less important for the prognosis of the patient. Whereas the prolongation of the repolarization in the basal ECG is associated with a higher mortality in our study

Robotic ablation of atrial fibrillation with a new remote catheter system

PURPOSE Pulmonary vein isolation (PVI) is widely established as a curative treatment option for atrial fibrillation (AF). A wide range of techniques to improve catheter manipulation and steerability has been developed over the past years. A new remote catheter system (RCS) has recently become available (Amigo Remote Catheter System, Catheter Robotics, Budd Lake, NJ, USA). Here, we present a dual-center study on the RCS for left atrial mapping and PVI in patients with paroxysmal AF compared to a control group undergoing conventional PVI. METHODS One hundred nineteen patients who underwent PVI for paroxysmal AF were studied. Forty patients underwent PVI with the use of the RCS. Seventy-nine patients, who underwent conventional PVI, served as control group. Procedural data were compared between the two groups. RESULTS PVI was achieved in all patients. In the RCS group compared to standard ablation group, there were no significant differences in procedure duration (159.1 ± 45.4 vs. 146 ± 30.1 min, p = 0.19), total energy delivery (78,146.3 ± 26,992.4 vs. 87,963.9 ± 79,202.1 Ws, p = 0.57), and total fluoroscopy time (21.2 ± 8.6 vs. 23.9 ± 5.4 min, p = 0.15). Operator fluoroscopy exposure was significantly reduced in the RCS group (13.4 ± 6.1 vs. 23.9 ± 5.4 min, p < 0.001). CONCLUSIONS These initial results suggest that left atrial mapping and PVI are feasible with the use of the Amigo RCS. Acute procedural efficacy is comparable to the standard approach. The use of the Amigo RCS leads to a significant reduction of operator fluoroscopy exposure