Effect of CPAP therapy on left atrial remodeling in patients with paroxysmal atrial fibrillation and obstructive sleep apnea undergoing pulmonary vein isolation

Aim. To study the isolated effect of obstructive sleep apnea (OSA) on left atrial (LA) remodeling in patients with paroxysmal atrial fibrillation (AF) who underwent pulmonary vein (PV) ablation and concomitant severe and moderate OSA.Material and methods. A subanalysis of echocardiographic data was performed in 50 patients with paroxysmal AF and moderate/severe OSA who underwent PV isolation and were followed up for 12 months (main group, 33; control group, 17). The clinical efficacy of catheter ablation was assessed after the end of the threemonth blind period. The following echocardiographic parameters were included in the subanalysis: anterior-posterior LA dimension, LA volume, LA volume index (LAVI), and pulmonary artery systolic pressure (PASP).Results. After 12 months, the control group showed a significant increase in the anterior-posterior LA dimension (40,5 (40-42) mm vs 42 (40-45) mm, p=0,037), LA volume (68,5 (58-74,5) ml vs 69 (63-89) ml, p=0,006), LAVI (35,0 (29-37) ml/m2 vs 35,5 (32-41,5) ml/m2, p=0,005) and PASP (27 (25-30) vs 30 (29-33), p=0,004). Intragroup analysis of patients not receiving continuous positive airway pressure (CPAP) therapy and without recurrent AF did not reveal significant changes in LA size (anterior-posterior LA dimension — 40 (40-42) mm vs 40 (40- 41) mm, p=0,317; LA volume — 63 (58-71) ml vs 64 (61-69) ml, p=0,509; LAVI — 32 (29-36) ml/m2 vs 33 (31-34) ml2, p=0,509).Conclusion. In patients with paroxysmal AF and concomitant moderate to severe OSA who underwent AF catheter treatment, the absence of CPAP therapy is not associated with a significant increase in the linear and volume LA dimensions in the absence of AF recurrence

New constraint on the existence of the mu+-> e+ gamma decay

The analysis of a combined data set, totaling 3.6 \times 10^14 stopped muons on target, in the search for the lepton flavour violating decay mu^+ -> e^+ gamma is presented. The data collected by the MEG experiment at the Paul Scherrer Institut show no excess of events compared to background expectations and yield a new upper limit on the branching ratio of this decay of 5.7 \times 10^-13 (90% confidence level). This represents a four times more stringent limit than the previous world best limit set by MEG.Comment: 5 pages, 3 figures, a version accepted in Phys. Rev. Let

The MEG detector for μ+→e+γ{\mu}+\to e+{\gamma} decay search

The MEG (Mu to Electron Gamma) experiment has been running at the Paul Scherrer Institut (PSI), Switzerland since 2008 to search for the decay \meg\ by using one of the most intense continuous $\mu^+$ beams in the world. This paper presents the MEG components: the positron spectrometer, including a thin target, a superconducting magnet, a set of drift chambers for measuring the muon decay vertex and the positron momentum, a timing counter for measuring the positron time, and a liquid xenon detector for measuring the photon energy, position and time. The trigger system, the read-out electronics and the data acquisition system are also presented in detail. The paper is completed with a description of the equipment and techniques developed for the calibration in time and energy and the simulation of the whole apparatus.Comment: 59 pages, 90 figure

Complete Genome Sequences of Cluster A6 and Cluster G1 Mycobacterium Smegmatis Phages Hoot and Jolene

We present the complete genome sequences of Mycobacterium smegmatis phages Hoot and Jolene, isolated in Las Vegas, NV. The phages were isolated and annotated by students enrolled in an undergraduate research course at the University of Nevada, Las Vegas. Hoot is a cluster A6 mycobacteriophage, while Jolene is in cluster G1

A limit for the mu -> e gamma decay from the MEG experiment

A search for the decay mu -> e gamma, performed at PSI and based on data from the initial three months of operation of the MEG experiment, yields an upper limit on the branching ratio of BR(mu -> e gamma) < 2.8 x 10**-11 (90% C.L.). This corresponds to the measurement of positrons and photons from ~ 10**14 stopped mu-decays by means of a superconducting positron spectrometer and a 900 litre liquid xenon photon detector.Comment: 13 pages, 9 figures. v2: improved estimate of photon reconstruction efficienc

The MEG detector for μ+→e+γ decay search

The MEG (Mu to Electron Gamma) experiment has been running at the Paul Scherrer Institut (PSI), Switzerland since 2008 to search for the decay mu(+) -> e(+)gamma by using one of the most intense continuous mu(+) beams in the world. This paper presents the MEG components: the positron spectrometer, including a thin target, a superconducting magnet, a set of drift chambers for measuring the muon decay vertex and the positron momentum, a timing counter for measuring the positron time, and a liquid xenon detector for measuring the photon energy, position and time. The trigger system, the read-out electronics and the data acquisition system are also presented in detail. The paper is completed with a description of the equipment and techniques developed for the calibration in time and energy and the simulation of the whole apparatus

Predictors of sustained isolation of pulmonary vein ostia with cryoballoon ablation using a second-generation cryoballoon Arctic Front Advance

Aim. To determine the electrophysiological and biophysical predictors of sustained isolation of pulmonary vein (PV) ostia, affecting the immediate and longterm results of interventional treatment of atrial fibrillation (AF) using cryoballoon ablation (CBA) with the second-generation cryoballoon Arctic Front Advance.Material and methods. The analysis included 143 PV in 37 patients with a paro-xysmal/persistent form of AF, which, after the primary CBA with the use of the second-generation cryoballoon, carried out additional interventions due to recurrence of AF and/or combined arrhythmia. During the primary CBA, the registration of biophysical and electrophysiological parameters of the procedure was performed. During the ablation in the right PV from the diagnostic electrode installed in the superior vena cava, the ipsilateral phrenic nerve was stimulated (2000 ms, 25 mA). When the phrenic nerve response to stimulation was decreased/disappeared, ablation ceased instantly. At the end of the procedure, isolation control of the PV was performed. A repeat/additional procedure was performed for the recurrence of AF and/or documented combined arrhythmia no earlier than 3 months after the initial ablation. The stability of the LV isolation was assessed using a circular mapping technique. According to the results of mapping, drugs were divided into 2 groups: isolated and with recurrent activity.Results. The frequency of sustained isolation of PV was 67,8%. Recurrent spike activity was recorded in 46 PV (32,2%). Higher frequency of registration of electrical isolation of PV in real time (68% vs 50%, p=0,001), stability of occlusion with a cryoballoon (85,5% vs 69,5%, p=0,024), low values of the minimum cryoballoon temperatures reached (49,2±6,3 vs 44,0±4,9, p&lt;0,0001) and less need for additional applications (8,3% vs 34,7%, p&lt;0,0001) were registered in the group of chronic isolation of PV. Multi-factor analysis of these parameters confirmed the predictor role of the minimum cryoballoon temperature. According to the ROC analysis, the threshold minimum temperature was 45,5° C with a sensitivity of 68% and a specificity of 60,9%.Conclusion. Cryoballoon isolation of PV ostia is an effective and safe method for achieving chronic isolation of PV. The minimum cryoballoon temperature with a threshold value of &lt;-45,5° C is an independent predictor of long-term isolation of PV

The effectiveness of catheter ablation in paroxysmal atrial fibrillation in patients with obstructive sleep apnea with/without use of continuous positive airway pressure: results of a 12-month follow-up

Aim. To assess the effectiveness of catheter ablation in paroxysmal atrial fibrillation (AF) in patients with moderate/severe obstructive sleep apnea (OSA) with/without use of continuous positive airway pressure (CPAP) therapy (&gt;4 hours per night).Material and methods. A total of 60 patients with paroxysmal AF and moderate/severe OSA after catheter pulmonary vein isolation were randomized into 2 groups (2:1 ratio): CPAP group (n=40) and control group (n=20). The follow-up period was 12 months and included visits after 3, 6 and 12 months. The effectiveness of catheter ablation was assessed after the 3-month blind period.Results. Freedom from arrhythmia in patients with CPAP therapy was documented in 82,9% and was significantly more common compared with the control group — 47,5% (p=0,032). Concurrent hypertension was a predictor of arrhythmia recurrence (odds ratio 24,1; 95% confidence interval 2,2-261,2).Conclusion. Treatment of OSA with CPAP therapy improves the effectiveness of catheter ablation in paroxysmal AF during a 12-month follow-up