A clinical-in silico study on the effectiveness of multipoint bicathodic and cathodic-anodal pacing in cardiac resynchronization therapy.

Up to one-third of patients undergoing cardiac resynchronization therapy (CRT) are nonresponders. Multipoint bicathodic and cathodic-anodal left ventricle (LV) stimulations could overcome this clinical challenge, but their effectiveness remains controversial. Here we evaluate the performance of such stimulations through both in vivo and in silico experiments, the latter based on computer electromechanical modeling. Seven patients, all candidates for CRT, received a quadripolar LV lead. Four stimulations were tested: right ventricular (RVS); conventional single point biventricular (S-BS); multipoint biventricular bicathodic (CC-BS) and multipoint biventricular cathodic-anodal (CA-BS). The following parameters were processed: QRS duration; maximal time derivative of arterial pressure (dPdtmax); systolic arterial pressure (Psys); and stroke volume (SV). Echocardiographic data of each patient were then obtained to create an LV geometric model. Numerical simulations were based on a strongly coupled Bidomain electromechanical coupling model. Considering the in vivo parameters, when comparing S-BS to RVS, there was no significant decrease in SV (from 45 ± 11 to 44 ± 20 ml) and 6% and 4% increases of dPdtmax and Psys, respectively. Focusing on in silico parameters, with respect to RVS, S-BS exhibited a significant increase of SV, dPdtmax and Psys. Neither the in vivo nor in silico results showed any significant hemodynamic and electrical difference among S-BS, CC-BS and CA-BS configurations. These results show that CC-BS and CA-BS yield a comparable CRT performance, but they do not always yield improvement in terms of hemodynamic parameters with respect to S-BS. The computational results confirmed the in vivo observations, thus providing theoretical support to the clinical experiments

Physical activity measured by implanted devices predicts atrial arrhythmias and patient outcome: Results of IMPLANTED (Italian Multicentre Observational Registry on Patients With Implantable Devices Remotely Monitored)

Background--To determine whether daily physical activity (PA), as measured by implanted devices (through accelerometer sensor), was related to the risk of developing atrial arrhythmias during long-term follow-up in a population of heart failure (HF) patients with an implantable cardioverter defibrillator (ICD). Methods and Results--The study population was divided into 2 equally sized groups (PA cutoff point: 3.5 h/d) according to their mean daily PA recorded by the device during the 30- to 60-day period post-ICD implantation. Propensity score matching was used to compare 2 equally sized cohorts with similar characteristics between lower and higher activity patients. The primary end point was time free from the first atrial high-rate episode (AHRE) of duration 656 minutes. Secondary end points were: first AHRE 656 hours, first AHRE 6548 hours, and a combined end point of death or HF hospitalization. Data from 770 patients (65\ub115 years; 66% men; left ventricular ejection fraction 35\ub112%) remotely monitored for a median of 25 months were analyzed. A PA =3.5 h/d was associated with a 38% relative reduction in the risk of AHRE 656 minutes (72-month cumulative survival: 75.0% versus 68.1%; log rank P=0.025), and with a reduction in the risk of AHRE 656 hours, AHRE 6548 hours, and the combined end point of death or HF hospitalization (all P < 0.05). Conclusions--In HF patients with ICD, a low level of daily PA was associated with a higher risk of atrial arrhythmias, regardless of the patients' baseline characteristics. In addition, a lower daily PA predicted death or HF hospitalization

Atrial fibrillation in patient with high thrombotic risk: which therapy?

We report the case of an elderly patient suffering for about 20 years of hypertensive cardiac hypertrophy, carotid and peripheral vasculopathy. The patient, initially treated with oral anticoagulant therapy (dicumarol) due to relapsing atrial fibrillation, is an example of long-term use of dabigatran, dictated by safety concern in a patient at high risk of bleeding: as demonstrated by the RE-LY trial, dabigatran 110 mg / day has a preventive effect on cerebral events similar warfarin but with a lower incidence of bleeding. In this case, at high risk both thrombotic and hemorrhagic, the choice of dabigatran was successful in the long term (Cardiology)

NEW PRODUCT DEVELOPMENT (NPD) SERVICE SUPPLIERS IN OPEN INNOVATION PRACTICES: PROCESSES AND ORGANIZATION FOR KNOWLEDGE EXCHANGE AND INTEGRATION

New Product Development (NPD) service providers have assumed a prominent role in enabling a more widespread use of Open Innovation strategies, thanks to their ability to acquire, recombine and sell specialized knowledge and technologies. This paper adopts the point of view of the NPD service provider to investigate the approaches it can employ in order to favor knowledge exchange with its clients, throughout the service delivery process. The research relies on a multiple case study, which focuses on three collaborative projects undertaken by a worldwide leading provider of NPD services with some of its most important clients. The analysis reveals some important findings. First, the NPD service provider uses standard approaches, both as regards process and organizational variables, to address two critical barriers toward a successful completion of the inter-organizational relationship: the tacit nature of the knowledge to be exchanged and the difficulties in predicting the content of collaboration activities. Second, in implementing these approaches, the NPD service provider takes into account the distinctive characteristics of each client and the peculiarities of the specific collaborative project. Besides providing several managerial insights that will be useful for managers working in NPD service providers, the paper contributes to the academic debate, e.g., investigating the importance of trust in successful inter-organizational knowledge exchange processes.

Coronary sinus for cardiac resynchronization therapy: leave it alone and go for the branch! a case report

Coronary sinus is the target of an increasing number of percutaneous interventional procedures. Thus, in some patients, conventional cardiac resynchronization therapy (CRT) may not be feasible or preferable, and 'alternative' CRT approaches should be applied

Understanding virtual knowledge brokers and their differences with traditional ones

Virtual knowledge brokers help their clients solve challenging innovation problems by leveraging the diverse knowledge basis of vast communities of solvers. Despite the increasing diffusion of virtual knowledge brokers, no efforts have been done so far to investigate the anatomy of the brokering process they follow to deliver a service to their clients. This paper analyses how virtual knowledge brokers go through the four macro-phases of the brokering process (i.e. access, learning, linking and implemenation) and points out the main differences with traditional brokers. The research is based on a multiple case study involving two Italian virtual knowledge brokers. The analysis suggests that virtual knowledge brokers are characterized by a stronger ability to access different knowledge domains in comparison with traditional knowledge brokers. However, virtual knowledge brokers are less effective in the learning and linking phases of the process, due to the distance that separates solvers and clients and the lack of communication and interaction between solvers. Starting from these insights, the ability of virtual and traditional knowledge brokers to solve different types of innovation problems is analyzed. The paper contains also a discussion of the managerial implications of this study, especially for those firms that has to select the best knowledge brokers with which to collaborate

Automotive application of lithium-ion batteries: control of commercial batteries in laboratory tests

In this work the behavior of commercial lithium-ions batteries for auto-motive sector usage have been analyzed. Trough laboratory tests the loss of the nominal capacity in a battery has been studied. In particular the three basic causes of this phenomenon such as the amount of power required during the discharge phase, the aging due to high number of cycles and the poorly management of a battery pack have been examined in order to try to identify and define a method to recover battery packs poorly managed