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Commercial, high-tech upper limb prostheses offer a lot of functionality and are equipped with high-grade control mechanisms. However, they are relatively expensive and are not accessible to the majority of amputees. Therefore, more affordable, accessible, open-source, and 3D-printable alternatives are being developed. A commonly proposed approach to control these prostheses is to use bio-potentials generated by skeletal muscles, which can be measured using surface electromyography (sEMG). However, this control mechanism either lacks accuracy when a single sEMG sensor is used or involves the use of wires to connect to an array of multiple nodes, which hinders patients' movements. In order to mitigate these issues, we have developed a circular, wireless s-EMG array that is able to collect sEMG potentials on an array of electrodes that can be spread (not) uniformly around the circumference of a patient's arm. The modular sEMG system is combined with a Bluetooth Low Energy System on Chip, motion sensors, and a battery. We have benchmarked this system with a commercial, wired, state-of-the-art alternative and found an r = 0.98 ( p < 0.01) Spearman correlation between the root-mean-squared (RMS) amplitude of sEMG measurements measured by both devices for the same set of 20 reference gestures, demonstrating that the system is accurate in measuring sEMG. Additionally, we have demonstrated that the RMS amplitudes of sEMG measurements between the different nodes within the array are uncorrelated, indicating that they contain independent information that can be used for higher accuracy in gesture recognition. We show this by training a random forest classifier that can distinguish between 6 gestures with an accuracy of 97%. This work is important for a large and growing group of amputees whose quality of life could be improved using this technology.

Background: Adding electroanatomical left atrial (LA) voltage mapping to cryoballoon ablation (CBA) improves validation of acute pulmonary vein isolation (PVI). Aims: To determine whether the addition of mapping can improve outcome and PVI durability. Methods: One-year outcome and PV reconnection (PVR) rate at first repeat ablation were studied in 400 AF patients in a propensity-matched analysis (age, AF type, CHA 2 DS 2 -VASc score) between Achieve catheter-guided CBA with additional EnSite LA voltage maps performed pre- and post-CBA (mapping group; N = 200) and CT- and Achieve catheter-guided CBA (control group; N = 200). Clinical success was defined as freedom of documented AF or atrial tachycardia (AT) > 30 s. PV reconnection patterns were characterized in repeat ablations. Results: At 1 year, 77 (19.25%) patients had recurrence of AF/AT, significantly lower than in the mapping group: 21 (10.5%) vs. 56 (28%), p < 0.001. Procedure time was shorter (72.2 ± 25.4 vs. 78.2 ± 29.3 min, p = 0.034) and radiation exposure lower (4465.0 ± 3454.6 Gy.cm 2 vs. 5940.5 ± 4290.5 Gy.cm 2 , p = 0.037). Use of mapping was protective towards AF/AT recurrence (HR = 0.348; 95% CI 0.210-0.579; p < 0.001), independent of persistent AF type (HR = 1.723; 95% CI 1.034-2.872; p = 0.037), and LA diameter (HR = 1.055; 95% CI 1.015-1.096; p = 0.006). At repeat ablation (N = 90), persistent complete PVI was seen in 14/20 (70.0%) versus 23/70 (32.9%) in the mapping and conventional group, respectively ( p = 0.03). Reconnection rate of the right inferior PV was lower with mapping (10.0% vs. 34,3%, p = 0.035). Conclusions: Adding electroanatomical LA voltage mapping to CBA improves 1-year clinical outcome and lowers both procedure time and radiation exposure. At repeat, use of mapping increases complete persistent PVI mainly by improving PVI durability of the RIPV.

Competing Interests: Disclosures The authors have no conflicts of interest to disclose.

Gender-related differences have been reported in patients who underwent pulmonary vein isolation (PVI). Atrial substrate plays a role in the outcomes after ablation but gender-related differences in atrial substrate have never been described in detail. We sought to analyze gender-related differences in atrial remodeling (spontaneous low-voltage zones [LVZs]) and their clinical relevance after PVI. We conducted a prospective multicenter study, including consecutive patients who underwent first PVI-only atrial fibrillation (AF) ablation. LVZs were analyzed on high-density electroanatomical maps collected with multipolar catheter, before PVI. In total, 262 patients (61 ± 11 years, 31% female, 50% persistent AF) were followed for 28 months. In women, LVZs were larger (10% vs 4% of left atrial surface [p <0.001]) and female gender was independently associated with fourfold higher risk of having advanced (LVZ > 15%) atrial remodeling (odds ratio 4.56, p <0.001). AF recurrence-free survival was not different between men and women (log-rank p = 0.2). Although LVZs were independently associated higher AF recurrences at multivariate analysis (hazard ratio [HR] 1.2, p = 0.038), female gender was not (HR 1.4, p = 0.211). Specifically, the LVZ cutoff to predict outcomes was different in men and women: >5% in men (HR 3.0, p <0.001), >15% in women (HR 2.7, p = 0.02). In conclusion, women have more widespread LVZ in all left atrial regions. Despite more extensive atrial remodeling, the AF recurrence rate is similar in men and women, and LVZs become prognostic in women only at high burden (>15%). LVZs seem to have a different prognostic role in men and women., Competing Interests: Declaration of Competing Interest The authors have no conflicts of interest to declare., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background Left atrial substrate may have mechanistic relevance for ablation of atrial fibrillation (AF). We sought to analyze the relationship between low-voltage zones (LVZs), transition zones, and AF recurrence in patients undergoing pulmonary vein isolation. Methods and Results We conducted a prospective multicenter study on consecutive patients undergoing pulmonary vein isolation-only approach. LVZs and transition zones (0.5-1 mV) were analyzed offline on high-density electroanatomical maps collected before pulmonary vein isolation. Overall, 262 patients (61±11 years, 31% female) with paroxysmal (130 pts) or persistent (132 pts) AF were included. After 28 months of follow-up, 73 (28%) patients experienced recurrence. An extension of more than 5% LVZ in paroxysmal AF and more than 15% in persistent AF was associated with recurrence (hazard ratio [HR], 4.4 [95% CI, 2.0-9.8], P <0.001 and HR, 1.9 [95% CI, 1.1-3.7], P =0.04, respectively). Significant association was found between LVZs and transition zones and between LVZs and left atrial volume index (LAVI) (both P <0.001). Thirty percent of patients had significantly increased LAVI without LVZs. Eight percent of patients had LVZs despite normal LAVI. Older age, female sex, oncological history, and increased AF recurrence characterized the latter subgroup. Conclusions In patients undergoing first pulmonary vein isolation, the impact of LVZs on outcomes occurs with lower burden in paroxysmal than persistent AF, suggesting that not all LVZs have equal prognostic implications. A proportional area of moderately decreased voltages accompanies LVZs, suggesting a continuous substrate instead of the dichotomous division of healthy or diseased tissue. LAVI generally correlates with LVZs, but a small subgroup of patients may present with disproportionate atrial remodeling, despite normal LAVI.

Background: in patients with heart failure (HF) and atrial fibrillation (AF), AF ablation improves left ventricular ejection fraction (LVEF), along with prognosis, in a variable percentage of patients. We aimed to investigate the predictors of LVEF recovery after AF ablation and to develop a prediction model for individualized assessment., Methods: we conducted an observational, retrospective, single-centre study on 111 consecutive patients with AF and HF with impaired LVEF (<50%) undergoing ablation. Patients were divided into Responder vs. Non-Responder according to the "Universal definition of HF". Clinical predictors were evaluated by multivariate logistic regression analysis and cross-validation technique. Independent predictors were used to build an internally validated prediction model., Results: Responders (54%) had significantly shorter QRS duration and less dilated left atrium. Persistent AF and absence of a known etiology were more frequent among Responders. AF recurrence was similar between the two groups (p = 0.2), but the percentage of patient with persistent AF after ablation was significantly lower among Responders (p < 0.001). Absence of known etiology, presence of persistent AF, left atrial volume index<50 mL/m 2 , and QRS < 120 msec were independent predictors of LVEF recovery and composed the Score (AUC 0.93;95%CI 0.88-0.98-p < 0.001). Patients with Score ≤ 1 had 90% likelihood of LVEF recovery, compared to 5% in patients with 3-6., Conclusions: Patients with wide QRS, known HF etiology, dilated left atrium, and paroxysmal AF were less likely to recover LVEF after AF ablation. A new score system based on the above-mentioned parameters adequately predicts LVEF recovery after AF ablation. These results warrant confirmation and prospective validation., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Introduction: Different methods are used for atrial fibrillation (AF) cycle length (CL) measurement with variable results. Previous studies of pulmonary vein (PV) CL measurement showed contradictory results on predicting PV isolation (PVI) efficacy. A novel simple method of measuring the average of 10 consecutive Fastest Atrial Repetitive Similar morphology signal (FARS 10 )-CL to characterize local atrial activity rate was evaluated prospectively., Methods: The intra-observer reproducibility of FARS 10 -CL and traditional AF-CL measurement of continuously fragmented coronary sinus (CS) signals were tested. We prospectively enrolled 100 consecutive patients (62 ± 10 years, 72% male) undergoing wide antral PVI only ablation for persistent AF, measured PV-FARS 10 -CLs, and evaluated long-term outcome., Results: The Kendall area correlation between repeated traditional AF-CL measurements was -0.006 and between repeated FARS 10 -CL measurements in the right and left atrial appendages, CS and PVs were 0.944, 0.859, 0.882, 0.675-0.955, respectively. Patients with recurrent atrial tachyarrhythmia had significantly longer fastest PV-FARS 10 -CL (172 ± 41 vs. 156 ± 41 ms, p = .047). Patients with high burden of spontaneous low-voltage zone (LVZ) had significantly longer fastest PV-FARS 10 -CL. Freedom from recurrent tachyarrhythmia at 24 months was 85% versus 59% in patients with fastest PV-FARS 10 -CL ≤ 140 versus >140 ms, p = .0018, respectively. In multivariable analysis fastest PV-FARS 10 -CL ≤ 140 ms was the only significant predictor of freedom from recurrent tachyarrhythmia., Conclusions: FARS 10 -CL measurements have a high reproducibility in contrast to traditional AF-CL measurement of continuously fragmented CS signals. Patients with high burden of LVZ have longer fastest PV-FARS 10 -CLs. Fastest PV-FARS 10 -CL ≤ 140 ms is associated with a high success of wide antral PVI-only ablation approach in persistent AF., (© 2022 Wiley Periodicals LLC.)

Background: Literature reports 5% of recurrence/failure in paediatric accessory pathway ablations. Our aim was to investigate the reasons underlying this finding and share techniques to obtain long-term success., Methods: Thirty-nine paediatric patients referred for a repeat procedure were analysed: characteristics of the pathways and the initial and redo procedures were identified., Results: Mean age was 11.9 ± 3.3 years (59% males). Three patients (8%) had multiple accessory pathways. The most frequent location was left lateral (26%). Left sided pathway recurrence was caused mainly by poor contact (60%) and inadequate mapping (40%). For right lateral accessory pathways, poor contact accounted for 70% of failures. For antero-septal and para-Hisian locations, the use of cryoablation and choice of low radiofrequency energy delivery accounted for > 75% of failures. Long-term success strategies included choice of contact force catheters and radiofrequency applications at the ventricular insertion of the pathway and in the aortic coronary cusps. In postero-septal substrates, the main reason accounting for failure was deep or epicardial location of the pathway (37%), solved by using an irrigated tip catheter or applying lesions within the coronary sinus, or applications from both right and left postero-septal areas., Conclusion: Acute failure and post-procedure recurrence in paediatric accessory pathway ablations have multiple reasons related to the characteristics of the pathway and the technology available. Accurate understanding of the anatomy, careful mapping and pacing manoeuvers, and incorporation of new technologies contribute to achieve a definitive success in > 98% of procedures., (© 2021. The Author(s).)

Etiologic factors and long-term outcomes of catheter ablation of atrial fibrillation (AF) in young patients have not been well characterized. This study aimed to analyze the etiologic factors and outcomes of pulmonary vein isolation (PVI) in patients with young-onset AF (young-AF, defined as having first documented episode <45 years). Consecutive patients with young-AF undergoing PVI (n = 197) in 2 academic centers were enrolled and followed for 36.1 ± 24.5 months. A control group of patients with AF onset ≥45 years (n = 554) was included. The most frequent risk factors in young-AF were intensive exercise (25%), moderate-to-heavy alcohol consumption (23%), and familial AF (22%). Compared with patients with AF onset ≥45-year, patients with young-AF were more often men (82% vs 66%, p <0.001), had more frequently paroxysmal AF (81% vs 60%, p <0.001), had less left atrial dilatation (40.9 ± 6.2 mm vs 44.2 ± 7.2 mm, p <0.001), and had lower 4-year recurrence rate after last PVI procedure (22% vs 45%, p <0.001). In young-AF, structural heart disease (SHD) was the only independent predictor of recurrence. Patients with young-AF selected to undergo cryoballoon (CB) ablation were younger (35.0 ± 7.7 vs 36.6 ± 6.7 years, p = 0.035) and had less persistent AF (6% vs 24%, p = 0.004) and coronary artery disease (2% vs 7%, p = 0.02) compared with radiofrequency ablation. After excluding patients with persistent AF and SHD, there was no difference in single procedural success between radiofrequency or CB PVI (27% vs 17%, p = 0.11). In conclusion, patients with young-AF have diverse etiologies and high single and multiprocedural PVI successes. SHD is the only independent predictor of recurrence. In patients with young-AF, there is a selection bias for CB ablation., Competing Interests: Disclosures The authors have no conflicts of interest to declare., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Coronary-subclavian steal syndrome (CSSS) is a severe complication of coronary artery bypass graft (CABG) surgery with internal mammary artery grafting. It is caused by functional graft failure due to a hemodynamically significant proximal subclavian artery stenosis. In this manuscript, we provide a comprehensive review of literature and we report a series of five consecutive CSSS cases. This case series illustrates the variable clinical presentation, thereby emphasizing the importance of raised awareness concerning this pathology in CABG patients., (© 2019 Wiley Periodicals, Inc.)

Background: Pulmonary vein isolation (PVI) modulates the intrinsic cardiac autonomic nervous system (ANS). We evaluated the impact of PVI on 5 non-invasive autonomic tests., Methods: Thirty patients (76% male, mean age 60.37 ± 9.02 years) with paroxysmal atrial fibrillation (AF) underwent cryoballoon-guided PVI. Five autonomic tests were performed 24hrs before and after PVI (N = 30) and repeated after 6months (N = 22). Parasympathetic function was measured by heart rate (HR) variability during deep breathing (E/I ratio, I-E difference), Valsalva maneuver (Valsalva-ratio) and head-up tilt test (30/15 ratio). Sympathetic function was measured by systolic BP response to sustained handgrip and 10' tilting and by diastolic BP response to cold water., Results: 24hrs after PVI, baseline HR increased from 57.93 ± 9.06 bpm to 71.10 ± 12.75 bpm (p < 0.001). At 6 months, baseline HR was lower than immediately post-PVI (62.59 ± 7.89 vs 71.36 ± 13.58 bpm, p = 0.032) but still higher in comparison to pre-PVI (62.59 ± 7.89 vs 57.09 ± 8.80 bpm, p < 0.001). No differences were seen in baseline BP and parasympathetic tests acutely and at 6months. Besides an acute lowering in systolic BP increase during handgrip test, all sympathetic tests remained unchanged., Conclusions: An acute HR increase attenuated at 6months and an acute lowered systolic BP response to sustained handgrip were the only changes after cryoballoon-guided PVI. Non-invasive autonomic tests seem therefore not appropriate to evaluate the autonomic modulatory effect of PVI, either due to a too limited sensitivity or a too localized effect of PVI to influence test results., (Copyright © 2019 Indian Heart Rhythm Society. Production and hosting by Elsevier B.V. All rights reserved.)

Aims: Treatment with percutaneous edge-to-edge mitral valve repair (Mitraclip) has recently been recommended as an alternative to conventional mitral valve repair for high surgical risk patients with symptomatic severe mitral regurgitation (MR). In this study, we report the first use of Mitraclip therapy in Belgium., Methods and Results: This prospective registry includes 41 consecutive patients treated with the Mitraclip in two Belgian centres from October 2010 to June 2013. Acute procedural success, in-hospital safety end points and clinical status were analysed on an intention-to-treat basis up to one year after the procedure. In addition, determinants of major adverse cardiac events (MACE, death, surgical mitral valve intervention, and rehospitalization for heart failure) were analysed. Acute procedural success (successful clip placement and reduction of colour Doppler flow MR to < or = 2) was obtained in 32 patients (78%) and 18 of these patients received two clips. The primary safety end point was reached in 36 pts (88%): one patient died due to intracranial bleeding, there were three urgent surgical interventions and one severe access site bleeding. The MACE rate after one year was 41% (17 patients). There were 11 deaths (27%), six surgical interventions (15%) and 10 rehospitalizations for heart failure (24%). Additional subgroup analysis revealed that the one-year MACE rate was particularly high in patients with left ventricular ejection fraction (LVEF) < 25%: 62% vs. 36% in patients with LVEF > or = 5% (P = 0.05). At one year, MR < or = 2+ and NYHA class < or = 2 was present in 83% of the surviving patients, Conclusion: In high-risk patients with functional MR, treatment with the Mitraclip-device is a feasible and safe option resulting in improvement of MR severity and clinical symptoms. However, as MACE is high in some subgroups (e.g. LVEF < 25%), careful patient selection is crucial to ensure the maximum benefit from this new technique.