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Aims: Sudden cardiac death (SCD) causes high mortality and substantial societal burdens for healthcare systems (HSs). The risk of SCD is significantly increased in patients with reduced left ventricular ejection fraction after myocardial infarction (MI). Current guidelines recommend re-evaluation of cardioverter-defibrillator implantation 40 days post-MI, earliest. Medical therapy alone does not provide sufficient protection against SCD, especially in the first month post-MI, and needs time. Consequently, there is a gap in care of high-risk patients upon hospital discharge. The wearable cardioverter defibrillator (WCD) is a proven safe, effective therapy, which temporarily protects from SCD. Little information on WCD cost-effectiveness exists. We conducted this research to demonstrate the medical need of the device in the post-MI setting defining WCD cost-effectiveness. Methods & results: Based on a randomized clinical trials (RCTs) and Italian and international data, we developed a Markov-model comparing costs, patient survival, and quality-of-life, and calculated the Incremental Cost-Effectiveness Ratio (ICER) of a WCD vs. current standard of care in post-MI patients. The rather conservative base case analysis – based on the RCT intention-to-treat results - produced an ICER of €47,709 per Quality Adjusted Life Year (QALY) gained, which is far lower than the accepted threshold of €60,000 in the Italian National HS. The ICER per Life Year (LY) gained was €38,276. Conclusion: WCD utilization in post-MI patients is clinically beneficial and cost-effective. While improving guideline directed patient care, the WCD can also contribute to a more efficient use of resources in the Italian HS, and potentially other HSs as well.

This critical review illustrates the pathophysiological aspects and available scientific evidence about cardiac contractility modulation therapy. A useful algorithm dealing with the essential decisional knots to consider for device implantation in patients with heart failure in NYHA class >II and ejection fraction <= 45% is presented. The present review paves the way for the development of an Italian registry aiming at analyzing the characteristics of implanted patients based on a multiparametric approach, including cardiac bio markers, to identify clinical profiles and predictors of response to therapy. The "Answers and Questions" section provides useful insights into pathophysiology, technical specifications, clinically relevant scenarios and future perspectives.

Pacemakers, implantable cardiac defibrillators, and cardiac resynchronization therapy devices are potentially life-saving treatments for a number of cardiac conditions, but are not without risk. Most concerning is the risk of a cardiac implantable electronic device (CIED) infection, which is associated with significant morbidity, increased hospitalizations, reduced survival, and increased healthcare costs. Recommended preventive strategies such as administration of intravenous antibiotics before implantation are well recognized. Uncertainties have remained about the role of various preventive, diagnostic, and treatment measures such as skin antiseptics, pocket antibiotic solutions, anti-bacterial envelopes, prolonged antibiotics post-implantation, and others. Guidance on whether to use novel device alternatives expected to be less prone to infections and novel oral anticoagulants is also limited, as are definitions on minimum quality requirements for centres and operators and volumes. Moreover, an international consensus document on management of CIED infections is lacking. The recognition of these issues, the dissemination of results from important randomized trials focusing on prevention of CIED infections, and observed divergences in managing device-related infections as found in an European Heart Rhythm Association worldwide survey, provided a strong incentive for a 2019 International State-of-the-art Consensus document on risk assessment, prevention, diagnosis, and treatment of CIED infections.

Pacemakers, implantable cardiac defibrillators, and cardiac resynchronization therapy devices are potentially life-saving treatments for a number of cardiac conditions, but are not without risk. Most concerning is the risk of a cardiac implantable electronic device (CIED) infection, which is associated with significant morbidity, increased hospitalizations, reduced survival, and increased healthcare costs. Recommended preventive strategies such as administration of intravenous antibiotics before implantation are well recognized. Uncertainties have remained about the role of various preventive, diagnostic, and treatment measures such as skin antiseptics, pocket antibiotic solutions, anti-bacterial envelopes, prolonged antibiotics post-implantation, and others. Guidance on whether to use novel device alternatives expected to be less prone to infections and novel oral anticoagulants is also limited, as are definitions on minimum quality requirements for centres and operators and volumes. Moreover, an international consensus document on management of CIED infections is lacking. The recognition of these issues, the dissemination of results from important randomized trials focusing on prevention of CIED infections, and observed divergences in managing device-related infections as found in an European Heart Rhythm Association worldwide survey, provided a strong incentive for a 2019 International State-of-the-art Consensus document on risk assessment, prevention, diagnosis, and treatment of CIED infections.

Contains fulltext : 238765.pdf (Publisher’s version ) (Closed access), With the global increase in device implantations, there is a growing need to train physicians to implant pacemakers and implantable cardioverter-defibrillators. Although there are international recommendations for device indications and programming, there is no consensus to date regarding implantation technique. This document is founded on a systematic literature search and review, and on consensus from an international task force. It aims to fill the gap by setting standards for device implantation.

Contains fulltext : 238765.pdf (Publisher’s version ) (Closed access), With the global increase in device implantations, there is a growing need to train physicians to implant pacemakers and implantable cardioverter-defibrillators. Although there are international recommendations for device indications and programming, there is no consensus to date regarding implantation technique. This document is founded on a systematic literature search and review, and on consensus from an international task force. It aims to fill the gap by setting standards for device implantation.

Contains fulltext : 238765.pdf (Publisher’s version ) (Closed access), With the global increase in device implantations, there is a growing need to train physicians to implant pacemakers and implantable cardioverter-defibrillators. Although there are international recommendations for device indications and programming, there is no consensus to date regarding implantation technique. This document is founded on a systematic literature search and review, and on consensus from an international task force. It aims to fill the gap by setting standards for device implantation.

Contains fulltext : 220908.pdf (Publisher’s version ) (Closed access), BACKGROUND: Morphology algorithms are currently recommended as a standalone discriminator in single-chamber implantable cardioverter defibrillators (ICDs). However, these proprietary algorithms differ in both design and nominal programming. OBJECTIVE: To compare three different algorithms with nominal versus advanced programming in their ability to discriminate between ventricular (VT) and supraventricular tachycardia (SVT). METHODS: In nine European centers, VT and SVTs were collected from Abbott, Boston Scientific, and Medtronic dual- and triple-chamber ICDs via their respective remote monitoring portals. Percentage morphology matches were recorded for selected episodes which were classified as VT or SVT by means of atrioventricular comparison. The sensitivity and related specificity of each manufacturer discriminator was determined at various values of template match percentage from receiving operating characteristics (ROC) curve analysis. RESULTS: A total of 534 episodes were retained for the analysis. In ROC analyses, Abbott Far Field MD (area under the curve [AUC]: 0.91; P < .001) and Boston Scientific RhythmID (AUC: 0.95; P < .001) show higher AUC than Medtronic Wavelet (AUC: 0.81; P < .001) when tested for their ability to discriminate VT from SVT. At nominal % match threshold all devices provided high sensitivity in VT identification, (91%, 100%, and 90%, respectively, for Abbott, Boston Scientific, and Medtronic) but contrasted specificities in SVT discrimination (85%, 41%, and 62%, respectively). Abbott and Medtronic's nominal thresholds were similar to the optimal thresholds. Optimization of the % match threshold improved the Boston Scientific specificity to 79% without compromising the sensitivity. CONCLUSION: Proprietary morphology discriminators show important differences in their ability to discriminate SVT. How much this impact the overall discrimination process remains to be investigated.

Contains fulltext : 220908.pdf (Publisher’s version ) (Closed access), BACKGROUND: Morphology algorithms are currently recommended as a standalone discriminator in single-chamber implantable cardioverter defibrillators (ICDs). However, these proprietary algorithms differ in both design and nominal programming. OBJECTIVE: To compare three different algorithms with nominal versus advanced programming in their ability to discriminate between ventricular (VT) and supraventricular tachycardia (SVT). METHODS: In nine European centers, VT and SVTs were collected from Abbott, Boston Scientific, and Medtronic dual- and triple-chamber ICDs via their respective remote monitoring portals. Percentage morphology matches were recorded for selected episodes which were classified as VT or SVT by means of atrioventricular comparison. The sensitivity and related specificity of each manufacturer discriminator was determined at various values of template match percentage from receiving operating characteristics (ROC) curve analysis. RESULTS: A total of 534 episodes were retained for the analysis. In ROC analyses, Abbott Far Field MD (area under the curve [AUC]: 0.91; P < .001) and Boston Scientific RhythmID (AUC: 0.95; P < .001) show higher AUC than Medtronic Wavelet (AUC: 0.81; P < .001) when tested for their ability to discriminate VT from SVT. At nominal % match threshold all devices provided high sensitivity in VT identification, (91%, 100%, and 90%, respectively, for Abbott, Boston Scientific, and Medtronic) but contrasted specificities in SVT discrimination (85%, 41%, and 62%, respectively). Abbott and Medtronic's nominal thresholds were similar to the optimal thresholds. Optimization of the % match threshold improved the Boston Scientific specificity to 79% without compromising the sensitivity. CONCLUSION: Proprietary morphology discriminators show important differences in their ability to discriminate SVT. How much this impact the overall discrimination process remains to be investigated.

Objective: To determine the influence of cognitive functioning on gait recovery after total hip arthroplasty. Design: Prospective cohort study. Setting: Rehabilitation hospital. Participants: 40 patients who underwent a total hip arthroplasty, with normal cognitive functioning and without any other relevant medical condition were recruited and studied before surgery and at the beginning and the end of the rehabilitation program. Main Outcome Measures: Gait speed (10-Meter Walk Test, 10MWT) and functional mobility (Timed Up and Go test, TUG), measured at the time of discharge from the rehabilitation unit, were the primary outcomes. The candidate predictors were the cognitive and psychological variables collected in the pre-surgery phase, together with other potentially informative measures such as age, education, perceived pain, body mass index, pre-surgical gait speed and functional mobility. Results: The results suggest the existence of a direct relationship between cognitive functioning, with specific reference to high-level frontal executive functions, and the post-operative progress: the better the cognitive functioning in the pre-operative phase, the better the course of recovery in terms of gait speed and functional mobility. In particular, the performance at the Frontal Assessment Battery test, together with age, perceived pain and pre-surgical gait speed/functional mobility was the best predictor of recovery of walking measured by 10MWT and TUG. Conclusions: The present study highlights the importance of cognitive functioning, together with clinical and demographic features, in the post-surgical recovery of walking, even in the absence of cognitive decline. In particular, these data show the crucial role of higher-order cognitive processes, such as executive functions, involved in the formulation of motor plans and their integration with proprioceptive and visual cues.

AIM: Ventricular tachycardia (VT)/ventricular fibrillation (VF) occurrence after cardiac resynchronization therapy-defibrillator (CRT-D) replacement is unknown; hence, there is no practical guideline to recommend either CRT-D or CRT-pacemaker at the time of device replacement. We observed the 1-year VT/VF occurrence after CRT-D replacement in a subanalysis of the Detect Long-term Complications after ICD Replacement (DECODE) registry. METHODS AND RESULTS: A total of 332 consecutive patients who had undergone CRT-D replacement from 2013 to 2015 were enrolled in 36 Italian centres. The primary endpoint was the number of patients with any appropriate implantable cardioverter-defibrillator (ICD) interventions during 12-month follow-up. The secondary endpoint comprised death from any cause and appropriate ICD interventions. At replacement, 214 (64.5%) patients had a left ventricular ejection fraction ≤ 35% and 138 (41.6%) patients had a secondary prevention indication for ICD. Seventy (21.1%) patients had no longer indication to ICD therapy. During a median follow-up period of 406.5 (362-533) days, VT/VF requiring therapy delivery occurred in 57 (17%) patients, specifically in 7% of those who no longer had an ICD indication. On multivariate analysis, number of criteria for ICD replacement independently predicted appropriate ICD intervention during follow-up [hazard ratio (HR) = 1.62, 95% confidence interval (CI) 1.07-2.46; log-rank P = 0.02]. The combined endpoint of death from any cause or appropriate ICD therapy occurred in 76 (23%) patients. Only NYHA class remained associated with this combined endpoint (HR = 1.97, 95% CI 1.23-3.14; P = 0.005). CONCLUSIONS: The DECODE registry showed the 'real-world' experience of CRT-D recipients approaching device replacement, in which 7% of patients who no longer had an indication for ICD therapy experienced appropriate ICD interventions.

Coal mines in the Bowen Basin are characterised by steep geothermal gradients and cooling is currently achieved mainly through rental surface bulk air cooling in the summer months. The systems are employed to maintain wet bulb temperatures to below 27 degrees C at which point the risks of heat stroke or other heat-related issues are manageable. Future mines will have to manage a thermal environment where virgin coal temperatures of more than 50 degrees C at a depth of 500 m are expected. Underground temperature profiles were evaluated of deep, gassy coal mines prone to spontaneous combustion and thermodynamic modelling was carried out on a longwall face including the leakage effects from goaf streams at various locations along the longwall face. The application of underground bulk air cooling, chilled water sprays on shearers and the resulting temperature profiles are considered. Cooling strategies are discussed including mid-gate mobile bulk air coolers, spot coolers, underground bulk air cooling and the use of chilled water to enhance the positional efficiency of cooling plants. Rental versus ownership of cooling plants is discussed as part of long-term cooling strategies., Coal mines in the Bowen Basin are characterised by steep geothermal gradients and cooling is currently achieved mainly through rental surface bulk air cooling in the summer months. The systems are employed to maintain wet bulb temperatures to below 27 degrees C at which point the risks of heat stroke or other heat-related issues are manageable. Future mines will have to manage a thermal environment where virgin coal temperatures of more than 50 degrees C at a depth of 500 m are expected. Underground temperature profiles were evaluated of deep, gassy coal mines prone to spontaneous combustion and thermodynamic modelling was carried out on a longwall face including the leakage effects from goaf streams at various locations along the longwall face. The application of underground bulk air cooling, chilled water sprays on shearers and the resulting temperature profiles are considered. Cooling strategies are discussed including mid-gate mobile bulk air coolers, spot coolers, underground bulk air cooling and the use of chilled water to enhance the positional efficiency of cooling plants. Rental versus ownership of cooling plants is discussed as part of long-term cooling strategies.

The aim of the FutureMine research initiative was to build on the DeepMine research programme and provide new technologies for use when mining for gold at depths greater than 3 500 m. Ventilation was one of four areas in the initiative, and the results of research into air distribution, air cooling, refrigeration and ventilation monitoring software are summarised. The aim was to improve the working environment while reducing costs. The areas covered include research into the development of a scrubber which would remove pollutants from air and so allow air to be recycled, the development of lightweight on-demand coolers for use in stopes, and software add-ons for the VUMA software ventilation simulation package., The aim of the FutureMine research initiative was to build on the DeepMine research programme and provide new technologies for use when mining for gold at depths greater than 3 500 m. Ventilation was one of four areas in the initiative, and the results of research into air distribution, air cooling, refrigeration and ventilation monitoring software are summarised. The aim was to improve the working environment while reducing costs. The areas covered include research into the development of a scrubber which would remove pollutants from air and so allow air to be recycled, the development of lightweight on-demand coolers for use in stopes, and software add-ons for the VUMA software ventilation simulation package.

Deep South African gold and platinum mines are divided into areas which can be sealed off from each other in the event of a major fire. An inert gas generator must be sited in a suitable position near to the seat of the fire, but also where there is enough space for the equipment and operators. The GAG-3A operates by drawing air through a dust filter and reducing the oxygen content to around 2% through a two-stage combustion of kerosene. The gases flow along water-jacketed cooling tubes to the diffuser chamber where the gas is cooled further. The gas/steam mixture is then blown into the sealed fire area. To keep the unit operational, a supply of 2 500 l/h of kerosene is needed and a minimum of 25 m3/s of fresh intake air and 16 l/s of water must be available. A programme of gas sampling should be undertaken to monitor the performance of the GAG., Deep South African gold and platinum mines are divided into areas which can be sealed off from each other in the event of a major fire. An inert gas generator must be sited in a suitable position near to the seat of the fire, but also where there is enough space for the equipment and operators. The GAG-3A operates by drawing air through a dust filter and reducing the oxygen content to around 2% through a two-stage combustion of kerosene. The gases flow along water-jacketed cooling tubes to the diffuser chamber where the gas is cooled further. The gas/steam mixture is then blown into the sealed fire area. To keep the unit operational, a supply of 2 500 l/h of kerosene is needed and a minimum of 25 m3/s of fresh intake air and 16 l/s of water must be available. A programme of gas sampling should be undertaken to monitor the performance of the GAG.

Detailed studies of different stoping configurations have been undertaken for mining operations extending to depths of 5 000 m below surface, where virgin rock temperatures approach 70 degrees C. Ventilation and cooling requirements to maintain air reject wet-bulb temperatures of 28 degrees C or better have been extensively evaluated. The layouts compared were strike pillars with breast layouts and dip pillars with down-dip and overhand or underhand breast layouts. Heat generated per ton mined was relatively low for dip-pillar underhand and overhand but higher for the down-dip scenario. Dip-pillar breast layouts were best for escape and rescue, while the strike-pillar layout was better for development and multi-blasting. The stope heat load was increased by 30% where there was no backfill, provided the backfill slurry was not at too high a temperature. Mine-wide ventilation costs varied by about 20% between layouts., Detailed studies of different stoping configurations have been undertaken for mining operations extending to depths of 5 000 m below surface, where virgin rock temperatures approach 70 degrees C. Ventilation and cooling requirements to maintain air reject wet-bulb temperatures of 28 degrees C or better have been extensively evaluated. The layouts compared were strike pillars with breast layouts and dip pillars with down-dip and overhand or underhand breast layouts. Heat generated per ton mined was relatively low for dip-pillar underhand and overhand but higher for the down-dip scenario. Dip-pillar breast layouts were best for escape and rescue, while the strike-pillar layout was better for development and multi-blasting. The stope heat load was increased by 30% where there was no backfill, provided the backfill slurry was not at too high a temperature. Mine-wide ventilation costs varied by about 20% between layouts.

Discussion is presented of optimised cooling systems for mines at extreme depths, focusing on the use of ice systems including characteristics and components of large ice generation systems, ice making equipment and conveying methods, and capital cost and power requirements. The very high cost of cooling deep mines is stressed and great efforts are needed to refine mining methods to reduce these costs. Improved mine design for future deep level mining in the Witwatersrand gold fields of South Africa will necessitate that cooling issues play a dominant role in mine planning. The cooling of mines relies on both refrigeration and ventilation systems. Mining in the Witwatersrand currently has workings at depths of 3 800 m and detailed planning is taking place for significant production at depths of 4 000 m and more. The virgin rock temperatures at these levels will be over 60 degrees C and this, along with the great depth to which the ventilation air must travel, creates extremely arduous cooling scenarios., Discussion is presented of optimised cooling systems for mines at extreme depths, focusing on the use of ice systems including characteristics and components of large ice generation systems, ice making equipment and conveying methods, and capital cost and power requirements. The very high cost of cooling deep mines is stressed and great efforts are needed to refine mining methods to reduce these costs. Improved mine design for future deep level mining in the Witwatersrand gold fields of South Africa will necessitate that cooling issues play a dominant role in mine planning. The cooling of mines relies on both refrigeration and ventilation systems. Mining in the Witwatersrand currently has workings at depths of 3 800 m and detailed planning is taking place for significant production at depths of 4 000 m and more. The virgin rock temperatures at these levels will be over 60 degrees C and this, along with the great depth to which the ventilation air must travel, creates extremely arduous cooling scenarios.