In experimental research, animal welfare should always be of the highest priority. Currently, physical in-person observations are the standard. This is time-consuming, and results are subjective. Video-based machine learning models for monitoring experimental pigs provide a continuous and objective observation method for animal misthriving detection. The aim of this study was to develop and validate a pig tracking technology, using video-based data in a machine learning model to analyze the posture and activity level of experimental pigs living in single-pig pens. A research prototype was created using a microcomputer and a ceiling-mounted camera for live recording based on the obtained images from the experimental facility, and a combined model was created based on the Ultralytics YOLOv8n for object detection trained on the obtained images. As a second step, the Lucas–Kanade sparse optical flow technique for movement detection was applied. The resulting model successfully classified whether individual pigs were lying, standing, or walking. The validation test showed an accuracy of 90.66%, precision of 90.91%, recall of 90.66%, and correlation coefficient of 84.53% compared with observed ground truth. In conclusion, the model demonstrates how machine learning can be used to monitor experimental animals to potentially improve animal welfare.

Organs obtained from brain dead donors can have suboptimal outcomes. Activation of the innate immune system and translocation of intestinal bacteria could be causative. Thirty two pigs were assigned to control, brain death (BD), BD + luminal intestinal polyethylene glycol (PEG), and BD + luminal intestinal University of Wisconsin solution (UW) groups. Animals were observed for 360 min after BD before organ retrieval. 2,000 mL luminal intestinal preservation solution was instilled into the duodenum at the start of organ procurement. Repeated measurements of plasma C3a, Terminal Complement Complex (TCC), IL-8, TNF, and lipopolysaccharide binding protein were analysed by immunoassays. C3a was significantly higher in the BD groups compared to controls at 480 min after brain death. TCC was significantly higher in BD and BD + UW, but not BD + PEG, compared to controls at 480 min. TNF was significantly higher in the BD group compared to all other groups at 480 min. LPS binding protein increased following BD in all groups except BD + PEG, which at 480 min was significantly lower compared with all other groups. Brain death induced innate immune system activation was decreased by luminal preservation using PEG during organ procurement, possibly due to reduced bacterial translocation.

Normothermic machine perfusion (NMP) is a clinical strategy to reduce renal ischemia-reperfusion injury (IRI). Optimal NMP should restore metabolism and minimize IRI induced inflammatory responses. Microdialysis was used to evaluate renal metabolism. This study aimed to assess the effect of complement inhibition on NMP induced inflammatory responses. Twenty-two pig kidneys underwent 18 h of static cold storage (SCS) followed by 4 h of NMP using a closed-circuit system. Kidneys were randomized to receive a C5-inhibitor or placebo during SCS and NMP. Perfusion resulted in rapidly stabilized renal flow, low renal resistance, and urine production. During SCS, tissue microdialysate levels of glucose and pyruvate decreased significantly, whereas glycerol increased (p < 0.001). In the first hour of NMP, glucose and pyruvate increased while glycerol decreased (p < 0.001). After 4 h, all metabolites had returned to baseline. Inflammatory markers C3a, soluble C5b-9, TNF, IL-6, IL-1β, IL-8, and IL-10 increased significantly during NMP in perfusate and kidney tissue. C5-inhibition significantly decreased perfusate and urine soluble C5b-9 (p < 0.001; p = 0.002, respectively), and tissue IL-1β (p = 0.049), but did not alter other inflammatory markers. Microdialysis can accurately monitor the effect of NMP on renal metabolism. Closed-circuit NMP induces inflammation, which appeared partly complement-mediated. Targeting additional immune inhibitors should be the next step.

Kidney extraction time has a detrimental effect on post-transplantation outcome. This study aims to improve the flush-out and potentially decrease ischemic injury by the addition of hydrogen sulphide (H2S) to the flush medium. Porcine kidneys (n = 22) were extracted during organ recovery surgery. Pigs underwent brain death induction or a Sham operation, resulting in four groups: donation after brain death (DBD) control, DBD H2S, non-DBD control, and non-DBD H2S. Directly after the abdominal flush, kidneys were extracted and flushed with or without H2S and stored for 13 h via static cold storage (SCS) +/− H2S before reperfusion on normothermic machine perfusion. Pro-inflammatory cytokines IL-1b and IL-8 were significantly lower in H2S treated DBD kidneys during NMP (p = 0.03). The non-DBD kidneys show superiority in renal function (creatinine clearance and FENa) compared to the DBD control group (p = 0.03 and p = 0.004). No differences were seen in perfusion parameters, injury markers and histological appearance. We found an overall trend of better renal function in the non-DBD kidneys compared to the DBD kidneys. The addition of H2S during the flush out and SCS resulted in a reduction in pro-inflammatory cytokines without affecting renal function or injury markers.

Background: Organs obtained from brain dead (BD) donors often have worse outcomes. Activation of the complement system and translocation of intestinal bacteria could be causative. We aimed to examine activation of the complement system following BD and evaluate the systemic and local effect of adding luminal intestinal preservation to classical vascular preservation. Methods and material: BD was induced in 30 pigs (four groups: control (n=7), BD alone (n=8), BD + luminal intestinal polyethylene glycol (PEG, n=7) and BD + luminal intestinal University of Wisconsin solution (UW, n=8) using a previously validated method and all animals were observed for 6 hours before organ retrieval. In the PEG and UW groups, 2000 ml of the selected solution was instilled into the duodenum during the organ procurement surgery. Repeated measurements of C3a, Terminal Complement Complex (TCC), IL-8 and TNF were performed in plasma at baseline, BD, 30, 60, 120, 240 and 360 minutes after BD, and following the intestinal intervention (480). Plasma lipopolysaccharide binding protein (LPS-BP) was measured at baseline, BD, and 480 minutes after BD. All were normalised to albumin concentration. Biopsies were taken from jejunum and ileum at time of removal and following 8, 14 and 24 hours of static cold storage (SCS) using UW. Preliminary analysis has been performed at 24 hours of SCS for the BD groups, full histology will be available soon. Results: All animals were kept circulatory- and respiratory stable until organ procurement. At 480 minutes, C3a was significantly higher in BD, BD+PEG, and BD+UW groups compared to control group (all p<0.05) (fig. 1A). TCC was significantly higher in the combined BD group compared to control at 360 minutes, at 480 minutes, the BD and BD+UW groups were significantly higher compared to the control group (all p<0.05) (fig. 1B). IL-8 and TNF were significantly higher in the BD group compared to all other groups at 480 minutes (p=0,003 and p=0.001) (fig. 1C and D). LPS-BP increased following induction of BD in all groups except BD+PEG, which at 480 minutes were significantly lower (p=0.002) (fig. 1E and F) compared with all other groups. Preliminary biopsies from the Jejunum after 24 hours of SCS show a reduced median Chiu/Park score in the BD+PEG (2.5) and BD+UW (2.0) groups compared to the BD group (fig. 2). Conclusion: The complement system is activated following BD independently of intestinal and luminal preservation and may lead to inflammation. Luminal intestinal preservation during organ procurement led to lower Chiu/Park scores, and reduced cytokine and LPS-BP expression, which may be due to reduced bacterial translocation occurring during surgery independent of BD. Luminal PEG intervention may be combined with early innate immune system inhibition in BD donors to prevent systemic inflammation, which hampers organ function.

An increasing body of research indicates that annular stability plays a key role for a successful aortic valve repair. The aim of this study was to evaluate and compare a novel open aortic annuloplasty ring (the A-ring) with the Dacron ring. Both rings were compared with native aortic roots in vitro. Eighteen aortic roots were included in the study and randomized into three groups: the native, Dacron, and A-ring group. The roots were evaluated in an in vitro physiologic pulsatile model simulating the left side of the heart. Aortic annulus diameters were significantly reduced both in the Dacron ring group (p = 0.003) and the A-ring group (p = 0.020) when compared with the native group. Both the Dacron ring and A-ring effectively downsized the aortic annulus diameter. The A-ring also displayed an ability to maintain aortic root distensibility during the cardiac cycle equally to the Dacron ring.

Previous studies have demonstrated superior patency of no-touch as compared to conventional saphenous vein grafts in coronary artery bypass grafting. We aimed to compare mid-term clinical outcomes of both techniques in a large cohort of routine patients. We identified all patients undergoing nonemergent primary coronary artery bypass grafting with either no-touch or conventional saphenous vein grafts at our institution between 2000 and 2020. Propensity score matching was used to create adjusted cohorts based on 5288 eligible patients. The primary outcome was the combined endpoint of all-cause mortality and repeat revascularization. Secondary outcomes were individual rates of all-cause mortality and repeat revascularization, surgical complications, and short-term mortality. Propensity score matching resulted in cohorts of no-touch (n = 923) and conventional (n = 923) saphenous vein grafted patients with comparable baseline characteristics. Mean follow-up time was significantly shorter for the no-touch compared to the conventional cohort (4.9 ± 2.3 vs 8.3 ± 2.6 years, P < 0.001). Up to 7-year follow-up, neither the rate of the primary composite endpoint nor death differed significantly between the cohorts. The rate of repeat revascularization was significantly higher in patients in the no-touch cohort (12.9% vs 9.3% at 7-year follow-up, P = 0.022. Post-hoc analysis of percutaneous coronary intervention during follow-up revealed comparable rates of saphenous vein graft failure (no-touch 42/923 (4.6%) vs conventional 32/923 (3.5%), P = 0.286). In this large propensity score matched registry study, coronary artery bypass with no-touch compared to conventional saphenous vein grafting did neither enhance mid-term survival nor reduce the rate of repeat revascularization.

ObjectivesTo describe the occurrence of significant pericardial effusion, and to investigate characteristics associated with pericardial effusion within three months following heart valve surgery.MethodsA retrospective, observational cohort study including adult patients undergoing heart valve surgery at Odense University Hospital from August 2013 to November 2017. Data were gathered from The Western Denmark Heart Registry and electronic patient records.Cox proportional hazard models were used to investigate the associations between characteristics associated with significant pericardial effusion during index admission and within 3 months. Results are presented as HR with 95% CI.ResultsIn total, 1460 patients were included (70% men, median age 71 years (IQR 63–76)) and of those, n=230 patients (16%) developed significant pericardial effusion.EuroScore II was significantly associated with an increased risk of pericardial effusion during index admission and associated with a lower risk following discharge (index admission HR 1.05, 95% CI 1.02 to 1.08, after discharge HR 0.80, 95% CI 0.69 to 0.92). Increasing age (HR 0.97, 95% CI 0.95 to 0.98 per year) and concomitant coronary artery bypass grafting versus isolated valve surgery (HR 0.58, 95% CI 0.35 to 0.97) were significantly associated with a reduced risk of pericardial effusions in both periods. Being a man (HR 2.30, 95% CI 1.32 to 4.01) and aortic valve disease versus mitral valve disease (HR 2.16, 95% CI 1.20 to 3.90) were significantly associated with an increased risk after discharge.ConclusionSignificant pericardial effusions requiring drainage were present in 16% of cases following heart valve surgery, and different clinical characteristics were associated with the development of effusion.

OBJECTIVES:The objectives of the study were to describe the causes of readmission from discharge to 30 days and from day 31 to 180 after discharge and to investigate the characteristics associated with overall and cause-specific readmissions after open-heart valve surgery.METHODS:A single-center, retrospective cohort of 980 patients undergoing open-heart valve surgery from 2013 to 2016. Time to the first readmission was analyzed using univariable and multivariable Cox proportional hazard models. Results are reported as hazard ratios (HR) with 95% confidence intervals (CI).RESULTS:In total, 366 patients (37%) experienced unplanned cardiac readmission within 180 days after discharge. Within 30 days after discharge, the most frequent causes of readmission were pericardial/pleural effusions (n = 87), infections (n = 50), and atrial fibrillation/flutter (n = 45). Accordingly, infections (n = 32) were the most common cause from day 31 to 180. No powerful predictors of overall cardiac readmission were identified, but several characteristics were associated with cause-specific readmissions: age ≤65 years (HR: 1.85; CI: 1.18-2.88), male gender (HR: 1.85; CI: 1.11-3.09), high alcohol intake (HR: 1.99; CI: 1.22-3.24) and mitral valve procedures (HR: 1.86; CI: 1.11-3.10) were associated with readmissions due to effusions. Ischemic heart disease with a prior percutaneous coronary intervention (HR: 2.94; CI: 1.53-5.63), mitral valve procedures (HR: 2.10; CI: 1.23-3.59), and postoperative atrial fibrillation/flutter (HR: 1.71; CI: 1.03-2.85) were associated with atrial fibrillation/flutter readmissions.CONCLUSION:Predicting overall readmissions after open-heart valve surgery is difficult as causes of readmissions vary and different causes are associated with different characteristics. Future studies should target reducing cause-specific readmissions.

BACKGROUND:Unplanned readmissions after heart valve surgery are common, and constitute a significant burden for the patient and the health care system. The objective was to investigate the effect of individualised follow-up after open heart valve surgery on a composite endpoint of first unplanned cardiac hospital readmission or all-cause mortality within 180 days of discharge.METHODS:The study is a prospective cohort study comparing the composite endpoint in patients undergoing early, individualised and intensified follow-up after heart valve surgery with a propensity matched historical control group. A total of 308 consecutive patients were enrolled in the prospective cohort study, 980 consecutive patients comprised the control group. The propensity matched group consisted of n = 300 (intervention) and n = 580 (controls). Time to first event was analysed using uni- and multivariable Cox proportional hazard analysis. Kaplan-Meier survival curves were constructed to assess the probability of survival without readmission.RESULTS:After 180 days, the proportion of patients experiencing the composite endpoint was significantly lower in the intervention group compared with the controls for the overall, unmatched population (23% vs. 38%; HR 0.55; 95% CI, 0.42 to 0.73; P < 0.001). The effect did not change in the propensity matched population (HR 0.57; 95% CI 0.43;0.75, P < 0.001). The difference was related to reduction in readmission rates, whereas death rates were similar in intervention and control group (1.6% vs. 1.8%).CONCLUSION:An intervention consisting of early, individualised and intensified follow-up after open heart valve surgery reduced the risk of a composite endpoint of first, unplanned cardiac hospital readmission or all-cause mortality within 180 days.

Data describe supplementary tables and figures related to the research article; Effect of early, individualised and intensified follow-up after open heart valve surgery on unplanned cardiac hospital readmissions and all-cause mortality [1]. Data on patients undergoing open heart valve surgery were presented in 308 patients in a prospective cohort and compared with 980 patients in a historical cohort. Included figures show inclusion and exclusion of patients (flowchart) and the specific elements of the intervention. Tables show causes of readmission and sensitivity analyses of differences among patients in the prospective intervention group compared with patients in the historical control group. Further results, interpretation and discussion of the included data can be found in the main research paper.

ObjectivesThe objective was to assess differences in healthcare costs within 180 days after discharge from open heart valve surgery in an intervention group receiving early, individualised and intensified follow-up compared with a historical control group.MethodsA cost-minimisation analysis comparing costs from a consecutive prospective cohort compared with a propensity matched cohort. Costs related to the intervention, hospital (outpatient visits and readmissions) and general practitioners (all contacts) were included. Data were obtained from electronic patient records and registry data. A logistic propensity model was used to identify the historical control group. Main results are presented as mean differences and 95% CIs based on bootstrapping.ResultsAfter matching, the analysis included 300 patients from the intervention group and 580 controls. The mean intervention cost was €171 (SD 79) per patient. After 180 days, the mean healthcare costs were €1284 (SD 2567) for the intervention group and €2077 (SD 4773) for the controls. The cost of the intervention group was €793 (p<0.001) less per patient. The cost differences were explained mainly by fewer readmissions, fewer overall emergency visits and fewer contacts to the general practitioner during out-of-hours in the intervention group.ConclusionsThe intervention consisting of early, individualised and intensified follow-up after open heart valve surgery significantly reduced the healthcare costs within 180 days after discharge.