Current State of the Surgical Treatment of Atrial Fibrillation

Surgery of atrial fibrillation (AF) was first described in 1991 by James Cox in what was named the Cox-Maze procedure, and over the years it has been considered the gold-standard treatment, with best results in maintaining sinus rhythm in the long term. Nevertheless, the complexity and aggressivity of the first techniques of cut-and-sew limited the application of this procedure, and few centers were dedicated to AF surgery. In the past years, however, new devices able to ablate atrial tissue with cryotherapy, radiofrequency, or ultrasounds have facilitated this operation. In the mid-term, other energy devices with laser or microwave have been abandoned due to a lack of consistency in getting transmural lesions in a consistent and reproducible manner. Additionally, better knowledge of the physiopathology of AF, with the importance of triggering zones around the pulmonary veins, has started new minimally invasive techniques to approach paroxysmal and persistent AF patients through thoracoscopy

Cadaver donation: structural integrity of pulmonary homografts harvested 48 h post mortem in the juvenile ovine model

Published ArticleAbstract Cryopreserved pulmonary homograft (CPH) implantation remains the gold standard for reconstruction of the right ventricular outflow tract (RVOT). Harvesting homografts\24-h post mortem is the international norm, thereby largely excluding cadaveric donors. This study examines the structural integrity and stability of ovine pulmonary homografts harvested after a 48-h post mortem period, cryopreserved and then implanted for up to 180 days. Fifteen ovine pulmonary homografts were harvested 48-h post mortem and cryopreserved. Five CPH served as a control group (group 1; n = 5). CPH were implanted in the RVOT of juvenile sheep and explanted after 14 days (group 2; n = 5) and 180 days (group 3; n = 5). Leaflet integrity was evaluated by strength analysis, using tensile strength (TS), Young’s modulus (YM) and thermal denaturation temperature (Td), and morphology, including haematoxylin and eosin (H&E), Picrosirius red staining, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and von Kossa stains. Echocardiography confirmed normal function in all implants. In explants, no reduction in TS, YM or Td could be demonstrated and H&E showed mostly acellular leaflet tissue with no difference on Picrosirius red. TEM demonstrated consistent collagen disruption after cryopreservation in all three groups, with no morphological deterioration during the study period. von Kossa stains showed mild calcification in group 3. No deterioration of structural integrity could be demonstrated using strength or morphological evaluations between the controls and implant groups over the study period. Extending the post mortem harvesting time of homografts beyond 24 h did not appear to negatively affect the long-term performance of such transplanted valves in this study

Historical Overview of Vascular Allograft Transplantation

There is a mix of therapeutic options for revascularisation in vascular surgery. The authors performed a literature review on the evolution of vascular allograft transplantation and its use and acceptance by vascular surgeons. This review exposed three stages: the first stage involved preliminary experimentation; the second stage was a decline in use due to long-term complications, and the third stage is its current use in special indications subject to a thorough analysis. There are few indications for the use of vascular allografts in clinical guidelines. However, there are publications of long series of case studies with variable results reflecting international use of the procedure. There is a current trend that favours its use with limited and individualised indications

Effectiveness of Fosfomycin for the Treatment of Multidrug-Resistant Escherichia coli Bacteremic Urinary Tract Infections

IMPORTANCE The consumption of broad-spectrum drugs has increased as a consequence of the spread of multidrug-resistant (MDR) Escherichia coli. Finding alternatives for these infections is critical, for which some neglected drugs may be an option. OBJECTIVE To determine whether fosfomycin is noninferior to ceftriaxone or meropenem in the targeted treatment of bacteremic urinary tract infections (bUTIs) due to MDR E coli. DESIGN, SETTING, AND PARTICIPANTS This multicenter, randomized, pragmatic, open clinical trial was conducted at 22 Spanish hospitals from June 2014 to December 2018. Eligible participants were adult patients with bacteremic urinary tract infections due to MDR E coli; 161 of 1578 screened patients were randomized and followed up for 60 days. Data were analyzed in May 2021. INTERVENTIONS Patients were randomized 1 to 1 to receive intravenous fosfomycin disodium at 4 g every 6 hours (70 participants) or a comparator (ceftriaxone or meropenem if resistant; 73 participants) with the option to switch to oral fosfomycin trometamol for the fosfomycin group or an active oral drug or pa renteral ertapenem for the comparator group after 4 days. MAIN OUTCOMES AND MEASURES The primary outcome was clinical and microbiological cure (CMC) 5 to 7 days after finalization of treatment; a noninferiority margin of 7% was considered. RESULTS Among 143 patients in the modified intention-to-treat population (median [IQR] age, 72 [62-81] years; 73 [51.0%] women), 48 of 70 patients (68.6%) treated with fosfomycin and 57 of 73 patients (78.1%) treated with comparators reached CMC (risk difference, -9.4 percentage points; 1-sided 95% CI, -21.5 to infinity percentage points; P = .10). While clinical or microbiological failure occurred among 10 patients (14.3%) treated with fosfomycin and 14 patients (19.7%) treated with comparators (risk difference, -5.4 percentage points; 1-sided 95% CI. -infinity to 4.9; percentage points; P = .19), an increased rate of adverse event-related discontinuations occurred with fosfomycin vs comparators (6 discontinuations [8.5%] vs 0 discontinuations; P = .006). In an exploratory analysis among a subset of 38 patients who underwent rectal colonization studies, patients treated with fosfomycin acquired a new ceftriaxone-resistant or meropenem-resistant gram-negative bacteria at a decreased rate compared with patients treated with comparators (0 of 21 patients vs 4 of 17 patients [23.5%]; 1-sided P = .01). CONCLUSIONS AND RELEVANCE This study found that fosfomycin did not demonstrate noninferiority to comparators as targeted treatment of bUTI from MDR E coli; this was due to an increased rate of adverse event-related discontinuations. This finding suggests that fosfomycin may be considered for selected patients with these infections

Effect of remote ischaemic conditioning on clinical outcomes in patients with acute myocardial infarction (CONDI-2/ERIC-PPCI): a single-blind randomised controlled trial.

BACKGROUND: Remote ischaemic conditioning with transient ischaemia and reperfusion applied to the arm has been shown to reduce myocardial infarct size in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PPCI). We investigated whether remote ischaemic conditioning could reduce the incidence of cardiac death and hospitalisation for heart failure at 12 months. METHODS: We did an international investigator-initiated, prospective, single-blind, randomised controlled trial (CONDI-2/ERIC-PPCI) at 33 centres across the UK, Denmark, Spain, and Serbia. Patients (age >18 years) with suspected STEMI and who were eligible for PPCI were randomly allocated (1:1, stratified by centre with a permuted block method) to receive standard treatment (including a sham simulated remote ischaemic conditioning intervention at UK sites only) or remote ischaemic conditioning treatment (intermittent ischaemia and reperfusion applied to the arm through four cycles of 5-min inflation and 5-min deflation of an automated cuff device) before PPCI. Investigators responsible for data collection and outcome assessment were masked to treatment allocation. The primary combined endpoint was cardiac death or hospitalisation for heart failure at 12 months in the intention-to-treat population. This trial is registered with ClinicalTrials.gov (NCT02342522) and is completed. FINDINGS: Between Nov 6, 2013, and March 31, 2018, 5401 patients were randomly allocated to either the control group (n=2701) or the remote ischaemic conditioning group (n=2700). After exclusion of patients upon hospital arrival or loss to follow-up, 2569 patients in the control group and 2546 in the intervention group were included in the intention-to-treat analysis. At 12 months post-PPCI, the Kaplan-Meier-estimated frequencies of cardiac death or hospitalisation for heart failure (the primary endpoint) were 220 (8·6%) patients in the control group and 239 (9·4%) in the remote ischaemic conditioning group (hazard ratio 1·10 [95% CI 0·91-1·32], p=0·32 for intervention versus control). No important unexpected adverse events or side effects of remote ischaemic conditioning were observed. INTERPRETATION: Remote ischaemic conditioning does not improve clinical outcomes (cardiac death or hospitalisation for heart failure) at 12 months in patients with STEMI undergoing PPCI. FUNDING: British Heart Foundation, University College London Hospitals/University College London Biomedical Research Centre, Danish Innovation Foundation, Novo Nordisk Foundation, TrygFonden

Offshore wind to hydrogen for powering port land mobility : Case study in Port of Valencia.

Maritime cargo transport is a major energy consumer and polluting sector, accounting for 90% of world trade in goods and responsible for 2.5% of global greenhouse gas emissions per year. The Port of Valencia, as Spanish and European Mediterranean leader in containerized cargo traffic, aims to reduce its carbon footprint in cargo operations by introducing green initiatives based on hydrogen and offshore wind energy generation; as established by the European Green Deal and the Valencia port strategy towards zero emissions by 2030. Thus, the objective of this study is to evaluate the potential of hydrogen generation by offshore wind energy to replace fossil fuel in the mobility of land cargo in the Port of Valencia. For this case study, it was analysed the feasibility of deploying an offshore wind farm 45 km from the Port of Valencia by studying more than 100 000 wind data collected at an altitude of 10 metres and using the Kubik formula to approximate this data to the altitude of the wind turbines and the continuous Weibull function to calculate the energy and power recovery from the wind. In addition, were assessed the input requirements of the largest operational PEM electrolyser to produce hydrogen, and were studied the hydrogen requirements of inland freight mobility vehicles, such as container yard tractors, RoRo tractors, reach stackers and about 3 000 inland connection trucks travelling 85,000 km per year. For the conversion of diesel to hydrogen, different methodologies were applied based on the accuracy of the data, where the most important factor is the selection of tank-to-wheel efficiencies. To give a flexible view to the project, Scenarios 1 to 5 have been presented depending on the scope of the diesel-to-hydrogen change and linked to the future development of this technologies. Scenario 1 sideline the truck consumption, which represents 94% of the totalenergy demand, while Scenario 5 considers the overall daily consumption of 200 000 liters of diesel that could be replaced with 34 000 kilograms of hydrogen, produced by a 100 MW electrolyser powered by about 350 MWp of offshore wind power.  This work demonstrates that there is a great opportunity for ports to become major hydrogen producers in the coming decades, reducing their inland footprint and presenting a major business opportunity. This study confirms that, efforts in vehicle performance studies are vital to obtain an accurate transition to green mobility in port logistics

Assessment of offshore wind transmission technologies for green hydrogen production : Case study in Gävleborg County, Sweden

The usage of green hydrogen is expected to reduce the annual greenhouse gas emissions by 2% that are currently generated by the consumption of fossil-based hydrogen, while also hard-to-abate industries that are difficult to shift to low-carbon alternatives in the future. Gävleborg county, a crucial part of Sweden's industrial value chain, aims to decrease its carbon footprint in hydrogen-based industries by producing competitive green hydrogen by deploying offshore wind energy along the Gävleborg coast. To enhance the industrial competitiveness of Gävleborg by making the most of the wind resources in the area, it is important to select suitable energy transmission technologies. Therefore, this study aims to evaluate the potential of different offshore wind-to-shore technologies and assess the feasibility of hydrogen production for dedicated future offshore wind plants in the region. This case study examined the annual average power and energy recovery from wind resources in two different locations along the Gävleborg coast. More than 100 000 wind data values collected over 14 years from the New European Wind Atlas database were analyzed using the continuous Weibull function. Moreover, to evaluate the energy losses in the transmission to shore it was used the π-equivalent schema for either high voltage alternating current (HVAC) or high voltage direct current (HVDC), considering different voltage levels or the usage of reactive compensation. Finally, the power and energy input requirements of the largest operational PEM electrolyzer for hydrogen production were assessed. Three different offshore wind farm designs have been proposed for analysis, varying the installed power capacity and distance from the shore in accordance with the current offshore wind farm pro-spects in the region. On the one hand, designs with lower power capacity and closer to the shore are more likely to use HVAC technology with low voltage levels and little significance on reactive compensation. On the other hand, larger offshore wind designs will potentially use either HVAC technology with higher voltage levels and reactive compensation, or HVDC technology. After analysis, it can be concluded that the deployment of any of the suggested offshore wind designs will have a significant impact on the region´s energy mix, covering most of the current Swedish hydrogen demand when considering dedicated offshore wind-to-hydrogen plants. Nevertheless, most of these plans are currently in the initial stages of conception and planning and are awaiting political initia-tives and technological advancements to reach a level of economic competitiveness. This study also shows that Gävleborg county has a significant opportunity to become a prominent hydrogen producer in the next few decades; not only reducing the national carbon footprint, but also providing a significant business opportunity for the region. Furthermore, the selection of the best-suited offshore wind-to-shore technology will have a great impact in the investment and efficiency of the project, thus highlighting the most cost-effective and competitive offshore wind farms in the region.Användningen av grön vätgas förväntas minska de årliga utsläppen av växthusgaser med 2 % för närvarande genererade av förbrukningen av fossilbaserad vätgas, samt från industrier som har svårt att övergå till alternativ med låga koldioxidutsläpp i framtiden. Gävleborgs län, som är en viktig del av Sveriges industriella värdekedja, har som mål att minska sitt koldioxidavtryck inom vätgasbaserade industrier genom att producera konkurrenskraftig grön vätgas med hjälp av havsbaserad vindkraft längs Gävleborgs kust. För att öka Gävleborgs industriella konkurrenskraft genom att utnyttja vindresurserna i området på bästa sätt är det viktigt att välja lämplig teknik för energiöverföring. Den här studien syftar därför till att utvärdera potentialen hos olika tekniker för överföring av havsbaserad vindkraft till land och bedöma genomförbarheten av vätgasproduktion för dedikerade framtida havsbaserade vindkraftverk i regionen. I denna fallstudie undersöktes den årliga genomsnittliga effekten och energitillförseln från vindresurser på två olika platser längs Gävleborgs kust. Mer än 100 000 vinddatavärden som samlats in under 14 år från databasen New European Wind Atlas analyserades med hjälp av den kontinuerliga Weibull-funktionen. För att utvärdera energiförlusterna i överföringen till land användes dessutom π-ekvivalentschemat för antingen högspänd växelström (HVAC) eller högspänd likström (HVDC), med beaktande av olika spänningsnivåer eller användning av reaktiv kompensation. Slutligen bedömdes effekt- och energibehovet för den största operativa PEM-elektrolysören för vätgasproduktion. Tre olika layouter för havsbaserade vindkraftparker har föreslagits för analys, där den installerade effektkapaciteten och avståndet från kusten varierade i enlighet med de aktuella utsikterna för havsbaserade vindkraftparker i regionen. Å ena sidan är det troligare att layouter med lägre effektkapacitet och närmare kusten använder HVAC-teknik med låga spänningsnivåer och liten betydelse för reaktiv kompensation. Å andra sidan kommer större havsbaserade vindkraftsanläggningar potentiellt att använda antingen HVAC-teknik med högre spänningsnivåer och reaktiv kompensation eller HVDC-teknik. Efter analysen kan man dra slutsatsen att utbyggnaden av någon av de föreslagna havsbaserade vindkraftsutformningarna kommer att ha en betydande inverkan på regionens energimix och täcka större delen av Sveriges nuvarande vätgasbehov om man beaktar dedikerade havsbaserade vindkraftverk för vätgas produktion. De flesta av dessa planer befinner sig dock för närvarande i ett inledande skede av utformning och planering och väntar på politiska initiativ och tekniska framsteg för att nå en nivå av ekonomisk konkurrenskraft. Denna studie visar också att Gävleborgs län har en betydande möjlighet att bli en framstående vätgasproducent under de närmaste decennierna, vilket inte bara minskar det nationella koldioxidavtrycket utan också ger regionen en betydande affärsmöjlighet. Vidare kommer valet av den bäst lämpade tekniken för överföring av havsbaserad vindkraft till land att ha stor betydelse för investeringar och effektivitet i projektet, och därmed bidra till de mest kostnadseffektiva och konkurrenskraftiga havsbaserade vindkraftparkerna i regionen

Offshore wind to hydrogen for powering port land mobility : Case study in Port of Valencia.

Maritime cargo transport is a major energy consumer and polluting sector, accounting for 90% of world trade in goods and responsible for 2.5% of global greenhouse gas emissions per year. The Port of Valencia, as Spanish and European Mediterranean leader in containerized cargo traffic, aims to reduce its carbon footprint in cargo operations by introducing green initiatives based on hydrogen and offshore wind energy generation; as established by the European Green Deal and the Valencia port strategy towards zero emissions by 2030. Thus, the objective of this study is to evaluate the potential of hydrogen generation by offshore wind energy to replace fossil fuel in the mobility of land cargo in the Port of Valencia. For this case study, it was analysed the feasibility of deploying an offshore wind farm 45 km from the Port of Valencia by studying more than 100 000 wind data collected at an altitude of 10 metres and using the Kubik formula to approximate this data to the altitude of the wind turbines and the continuous Weibull function to calculate the energy and power recovery from the wind. In addition, were assessed the input requirements of the largest operational PEM electrolyser to produce hydrogen, and were studied the hydrogen requirements of inland freight mobility vehicles, such as container yard tractors, RoRo tractors, reach stackers and about 3 000 inland connection trucks travelling 85,000 km per year. For the conversion of diesel to hydrogen, different methodologies were applied based on the accuracy of the data, where the most important factor is the selection of tank-to-wheel efficiencies. To give a flexible view to the project, Scenarios 1 to 5 have been presented depending on the scope of the diesel-to-hydrogen change and linked to the future development of this technologies. Scenario 1 sideline the truck consumption, which represents 94% of the totalenergy demand, while Scenario 5 considers the overall daily consumption of 200 000 liters of diesel that could be replaced with 34 000 kilograms of hydrogen, produced by a 100 MW electrolyser powered by about 350 MWp of offshore wind power.  This work demonstrates that there is a great opportunity for ports to become major hydrogen producers in the coming decades, reducing their inland footprint and presenting a major business opportunity. This study confirms that, efforts in vehicle performance studies are vital to obtain an accurate transition to green mobility in port logistics

Assessment of offshore wind transmission technologies for green hydrogen production : Case study in Gävleborg County, Sweden

The usage of green hydrogen is expected to reduce the annual greenhouse gas emissions by 2% that are currently generated by the consumption of fossil-based hydrogen, while also hard-to-abate industries that are difficult to shift to low-carbon alternatives in the future. Gävleborg county, a crucial part of Sweden's industrial value chain, aims to decrease its carbon footprint in hydrogen-based industries by producing competitive green hydrogen by deploying offshore wind energy along the Gävleborg coast. To enhance the industrial competitiveness of Gävleborg by making the most of the wind resources in the area, it is important to select suitable energy transmission technologies. Therefore, this study aims to evaluate the potential of different offshore wind-to-shore technologies and assess the feasibility of hydrogen production for dedicated future offshore wind plants in the region. This case study examined the annual average power and energy recovery from wind resources in two different locations along the Gävleborg coast. More than 100 000 wind data values collected over 14 years from the New European Wind Atlas database were analyzed using the continuous Weibull function. Moreover, to evaluate the energy losses in the transmission to shore it was used the π-equivalent schema for either high voltage alternating current (HVAC) or high voltage direct current (HVDC), considering different voltage levels or the usage of reactive compensation. Finally, the power and energy input requirements of the largest operational PEM electrolyzer for hydrogen production were assessed. Three different offshore wind farm designs have been proposed for analysis, varying the installed power capacity and distance from the shore in accordance with the current offshore wind farm pro-spects in the region. On the one hand, designs with lower power capacity and closer to the shore are more likely to use HVAC technology with low voltage levels and little significance on reactive compensation. On the other hand, larger offshore wind designs will potentially use either HVAC technology with higher voltage levels and reactive compensation, or HVDC technology. After analysis, it can be concluded that the deployment of any of the suggested offshore wind designs will have a significant impact on the region´s energy mix, covering most of the current Swedish hydrogen demand when considering dedicated offshore wind-to-hydrogen plants. Nevertheless, most of these plans are currently in the initial stages of conception and planning and are awaiting political initia-tives and technological advancements to reach a level of economic competitiveness. This study also shows that Gävleborg county has a significant opportunity to become a prominent hydrogen producer in the next few decades; not only reducing the national carbon footprint, but also providing a significant business opportunity for the region. Furthermore, the selection of the best-suited offshore wind-to-shore technology will have a great impact in the investment and efficiency of the project, thus highlighting the most cost-effective and competitive offshore wind farms in the region.Användningen av grön vätgas förväntas minska de årliga utsläppen av växthusgaser med 2 % för närvarande genererade av förbrukningen av fossilbaserad vätgas, samt från industrier som har svårt att övergå till alternativ med låga koldioxidutsläpp i framtiden. Gävleborgs län, som är en viktig del av Sveriges industriella värdekedja, har som mål att minska sitt koldioxidavtryck inom vätgasbaserade industrier genom att producera konkurrenskraftig grön vätgas med hjälp av havsbaserad vindkraft längs Gävleborgs kust. För att öka Gävleborgs industriella konkurrenskraft genom att utnyttja vindresurserna i området på bästa sätt är det viktigt att välja lämplig teknik för energiöverföring. Den här studien syftar därför till att utvärdera potentialen hos olika tekniker för överföring av havsbaserad vindkraft till land och bedöma genomförbarheten av vätgasproduktion för dedikerade framtida havsbaserade vindkraftverk i regionen. I denna fallstudie undersöktes den årliga genomsnittliga effekten och energitillförseln från vindresurser på två olika platser längs Gävleborgs kust. Mer än 100 000 vinddatavärden som samlats in under 14 år från databasen New European Wind Atlas analyserades med hjälp av den kontinuerliga Weibull-funktionen. För att utvärdera energiförlusterna i överföringen till land användes dessutom π-ekvivalentschemat för antingen högspänd växelström (HVAC) eller högspänd likström (HVDC), med beaktande av olika spänningsnivåer eller användning av reaktiv kompensation. Slutligen bedömdes effekt- och energibehovet för den största operativa PEM-elektrolysören för vätgasproduktion. Tre olika layouter för havsbaserade vindkraftparker har föreslagits för analys, där den installerade effektkapaciteten och avståndet från kusten varierade i enlighet med de aktuella utsikterna för havsbaserade vindkraftparker i regionen. Å ena sidan är det troligare att layouter med lägre effektkapacitet och närmare kusten använder HVAC-teknik med låga spänningsnivåer och liten betydelse för reaktiv kompensation. Å andra sidan kommer större havsbaserade vindkraftsanläggningar potentiellt att använda antingen HVAC-teknik med högre spänningsnivåer och reaktiv kompensation eller HVDC-teknik. Efter analysen kan man dra slutsatsen att utbyggnaden av någon av de föreslagna havsbaserade vindkraftsutformningarna kommer att ha en betydande inverkan på regionens energimix och täcka större delen av Sveriges nuvarande vätgasbehov om man beaktar dedikerade havsbaserade vindkraftverk för vätgas produktion. De flesta av dessa planer befinner sig dock för närvarande i ett inledande skede av utformning och planering och väntar på politiska initiativ och tekniska framsteg för att nå en nivå av ekonomisk konkurrenskraft. Denna studie visar också att Gävleborgs län har en betydande möjlighet att bli en framstående vätgasproducent under de närmaste decennierna, vilket inte bara minskar det nationella koldioxidavtrycket utan också ger regionen en betydande affärsmöjlighet. Vidare kommer valet av den bäst lämpade tekniken för överföring av havsbaserad vindkraft till land att ha stor betydelse för investeringar och effektivitet i projektet, och därmed bidra till de mest kostnadseffektiva och konkurrenskraftiga havsbaserade vindkraftparkerna i regionen