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Background: Sudden cardiac arrest (SCA) risk stratification in patients with mitral valve prolapse (MVP) may be complicated by other potential causes of arrhythmia., Objective: We aimed to characterize SCA survivors with isolated MVP (iMVP) and non-isolated MVP (non-iMVP) and to assess their long-term follow-up., Methods: This ambispective study included 75 patients with MVP who experienced SCA and were treated in our center between 2009 and 2024. They were divided into 3 groups according to probability of relation between SCA and comorbidities. The control group comprised 112 participants with MVP but without a history of SCA. We analyzed all available electrocardiograms, Holter electrocardiography monitoring, and echocardiograms, including longitudinal strain. A novel parameter, the systolic atrial-directed notch (SADN), was tested., Results: SCA survivors with iMVP (n = 28) had higher prevalence of mitral annular disjunction (80% vs 35.7%; P = .006), Pickelhaube sign (60% vs 8.3%; P = .008), and SADN >2 mm (69.6% vs 14.3%; P = .001) as well as higher absolute longitudinal strain values in basal and mid segments of the inferior and inferolateral wall than patients with SCA and non-iMVP without other defined structural heart diseases (n = 14). The differences were also observed in comparison to the control group. The cumulative incidence of appropriate implantable cardioverter-defibrillator shocks within 6 years was 62% in patients with iMVP and 23% in the group with non-iMVP without other defined structural heart diseases., Conclusion: Echocardiographic findings such as mitral annular disjunction, SADN, Pickelhaube sign, and increased segmental strain may be useful in the assessment of the relation between SCA and MVP. Malignant arrhythmias often recur in SCA survivors with iMVP., Competing Interests: Disclosures The authors have no conflicts of interest to disclose., (Copyright © 2025 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

One of the biggest problems of upper limb transplantation is lack of certainty as to whether a patient will be able to control voluntary movements of transplanted hands. Based on findings of the recent research on brain cortex plasticity, a premise can be drawn that mental training supported with visual and sensory feedback can cause structural and functional reorganization of the sensorimotor cortex, which leads to recovery of function associated with the control of movements performed by the upper limbs. In this study, authors - based on the above observations - propose the computer-aided training (CAT) system, which generating visual and sensory stimuli, should enhance the effectiveness of mental training applied to humans before upper limb transplantation. The basis for the concept of computer-aided training system is a virtual hand whose reaching and grasping movements the trained patient can observe on the VR headset screen (visual feedback) and whose contact with virtual objects the patient can feel as a touch (sensory feedback). The computer training system is composed of three main components: (1) the system generating 3D virtual world in which the patient sees the virtual limb from the perspective as if it were his/her own hand; (2) sensory feedback transforming information about the interaction of the virtual hand with the grasped object into mechanical vibration; (3) the therapist's panel for controlling the training course. Results of the case study demonstrate that mental training supported with visual and sensory stimuli generated by the computer system leads to a beneficial change of the brain activity related to motor control of the reaching in the patient with bilateral upper limb congenital transverse deficiency., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Background: Published data concerning risk factors of VF in WPW patients are inconsistent or contradictory., Methods and Results: We included 1007 patient (pts) (mean age 35 years; 45% female) with an accessory pathway (AP) referred for non pharmacological treatment. Group 1 consisted of 56 pts (42M, aged 34 ± 15 yrs) with an AP and documented VF and Group 2-951 pts (513M, aged 35 ± 15 yrs) with an AP and without VF. Univariate predictors of VF were: overt pre-excitation, male gender, multiple AP, large AP. Multivariate predictors were: overt pre-excitation, male gender and MAP. The mean shortest pre-excited RR interval during AF was significantly shorter in Group 1: 205 ± 27 vs. 243 ± 64, P=0.019. VF as an end point of the first arrhythmia episode (AVRT or AF) was observed in 20 pts (15M, 5F). Primary VF (no documented arrhythmia prior to aborted SCD) occurred in 16 pts (13M, 3F). The mean age of primary VF pts was significantly lower than of pts with history of AVRT or AVRT and/or AF (24.5 vs. 36.5 vs. 38 yrs., P<0.005 and P=0.002, respectively). Age at VF occurrence shows a bi-modal distribution with peak occurrences in the 2-nd/3-rd and 5-th decades., Conclusion: In patients with an accessory pathway, overt pre-excitation, male gender and multiple AP constitute independent risk factors of VF episodes. Young patients in the 2-nd/3-rd and older patients in the 5-th decade might be at higher risk of VF occurrence., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Many conditions remodel the heart muscle such that it results in a perturbation of cells coupling. The effect of this perturbation on the stability of the spiral waves of electrochemical activity is not clear. We used the FitzHugh-Nagumo model of an excitable medium to model the conduction of the activation waves in a two-dimensional system with inhomogeneous anisotropy level. Inhomogeneity of the anisotropy level was modeled by adding Gaussian noise to diffusion coefficients corresponding with lateral coupling of the cells. Low noise levels resulted in a stable propagation of the spiral wave. For large noise level conduction was not possible due to insufficient coupling in direction perpendicular to fibers. For intermediate noise intensities, the initial wave broke up into several independent spiral waves or waves circulating around conduction obstacles. At an optimal noise intensity, the number of wavelets was maximized-a form of anti-coherent resonance was obtained. Our results suggest that the inhomogeneity of conduction anisotropy may promote wave breakup and hence play an important role in the initiation and perpetuation of the cardiac arrhythmias., (Copyright © 2010 Elsevier Ltd. All rights reserved.)