Mesenteric Ischemia after Cardiac Surgery.

BACKGROUND: Mesenteric ischemia (Me-Is) after cardiac surgery is underreported in present literature but has still earned the bad reputation of a dismal prognosis. This study adds clinical outcomes in a large patient cohort. METHODS: Between 2009 and 2019 of the 22,590 patients undergoing cardiac surgery at our facility 106 (0.47%) developed Me-Is postoperatively. Retrospective patient data was analyzed. Additionally, patients were stratified by outcome-survivors and nonsurvivors. RESULTS: Patients were predominantly male (n = 68, 64.2%), mean age was 71.2 ± 9.3 years. Most procedures were elective (n = 85, 80.2%) and comprised of more complex combined procedures (50.9%) and redos (17.9%). Mean EuroSCORE II averaged 10.9 ± 12.2%. Survival at 30 days was 49.1% (n = 52). Clinical baseline and procedural characteristics did not differ significantly between survivors and nonsurvivors. The median postoperative interval until symptom onset was 5 days in both groups. Survivors were more frequently diagnosed by computed tomography and nonsurvivors based on clinical symptoms. Me-Is was predominantly nonocclusive (n = 84, 79.2%). Laparotomy was the main treatment in both groups (n = 45, 78.8% vs. n = 48, 88.9%, p = 0.94). Predictors of mortality were maximum norepinephrine doses (hazard ratio [HR] 8.29, confidence interval [CI] 3.39-20.26, p < 0.0001), lactate levels (HR 1.06, CI 1.03-1.09), and usage of inotropes (HR 2.46, CI 1.41-4.30). CONCLUSION: The prognosis of Me-Is following cardiac surgery is poor-independently from diagnostic or treatment patterns. There exists a significant asymptomatic time period postoperatively, in which pathophysiologic processes seem to cross the Rubicon. After clinical demarcation, the further course can almost no longer be influenced.

Tissue requirements for the application of aortic valve neocuspidization - appropriate pericardium properties and homogeneity?

OBJECTIVE: Aortic valve neocuspidization (AVNeo) using autologous pericardium is a promising technique. Expected advantages are reduced immune response, appropriate biomechanics and lower treatment expenses. Nevertheless, autologous pericardium can be affected by patient's age and comorbidities. Usually, glutaraldehyde (GA) - fixed bovine pericardium is the basic material for aortic valve prostheses, easy available and carefully pre-examined in a standardized fabrication process. Aim of the study is the verification of autologous pericardial tissue homogeneity by analysing tissue thickness, biomechanics and extracellular matrix (ECM) composition. METHODS: Segments of human GA-fixed pericardium selected by the surgeon based on visual criteria for cusp pre-cut and remaining after surgical AV replacement were investigated in comparison to bovine standard tissue treated equivalently. Pericardium sampling was performed at up to three positions of each sutured cusp for histological or biomechanical analysis, according to tissue availability. RESULTS AND CONCLUSIONS: Human pericardia exhibited a higher heterogeneity in collagen content, density of vessel structures and elastic moduli. Thickness, vessel density and collagen and elastin content differed significantly between the species. In contrast, significant interindividual differences were detected in most properties investigated for human pericardial samples but only for tissue thickness in bovine tissues. Higher heterogeneity of human pericardium, differing vessel and collagen content compared to bovine state-of-the-art material might be detrimental for long term AV functionality or deterioration and have to be intensely investigated in patients follow up after autologous cusp replacement.

Clinical Outcomes after Multivalve Surgery in Octogenarians: Evaluating the Need for a Paradigm Shift.

(1) Background: this study addresses the lack of comprehensive research on outcomes in octogenarians undergoing cardiac surgery for multivalvular disease, emphasizing the need for a critical examination of the intervention's overall worth in this aging population. (2) Methods: By analyzing short-term and mid-term data from 101 consecutive octogenarian patients undergoing multivalve surgery, the study identifies predictors for in-hospital and one-year mortality. (3) Results: In-hospital mortality increased fourfold with the occurrence of at least one postoperative complication. Octogenarians undergoing multivalve surgery experienced an in-hospital mortality rate of 13.9% and an overall one-year mortality rate of 43.8%. Postoperative delirium was identified as an independent risk factor, contributing to elevated risks of both in-hospital and one-year mortality. Prolonged surgical procedure time emerged as an independent risk factor associated with increased in-hospital mortality. Continuous veno-venous hemodialysis showed an independent impact on in-hospital mortality. Both re-intubation and the transfusion of packed red blood cells were identified as independent risk factors for one-year mortality. (4) Conclusions: This study urges a critical examination of the justification for multivalve surgeries in high-risk elderly patients, emphasizing a paradigm shift. It advocates for interdisciplinary collaboration and innovative strategies, such as staged hybrid procedures, to improve therapeutic approaches for this challenging patient group to achieve a better therapeutic outcome for these patients.

Right Anterior versus Right Transaxillary Access for Minimally Invasive Aortic Valve Replacement: A Propensity Matched Competitive Analysis.

(1) Background: Right anterior thoracotomy (RAT-AVR) has been the sole established sternum-sparing technique for minimally invasive aortic valve replacement (MICS-AVR) thus far. Nevertheless, transaxillary access, known as Minimally Invasive Cardiac LATeral Surgery (MICLATS-AVR), represents the latest and innovative advancement in sternum-sparing MICS-AVR access routes. In this study, procedural and clinical outcomes of a substantial transaxillary MICS-AVR cohort are compared to those of a RAT-AVR control group; (2) Patients and Methods: This retrospective study included 918 consecutive patients who underwent MICS-AVR at our facility between 2014 and 2022. This cohort was divided into two surgical access-related groups: RAT-AVR (n = 492) and MICLATS-AVR (n = 426). Procedural data, operative morbidity, and mortality were compared between groups. Further analysis was performed using propensity score matching; (3) Results: After matching, 359 pairs of patients were included and analyzed. There were no notable differences observed between the two groups regarding major adverse cardio-cerebral events. Despite longer cardiopulmonary bypass time in the MICLATS-AVR group (63.1 ± 20.4 min vs. 66.4 ± 18.2 min; p ≤ 0.001) the skin-to-skin time (129.4 ± 35.9 min. vs. 126.5 ± 29.8 min.; p = 0.790) and the aortic cross-clamp time was comparable between both groups (41.9 ± 13.3 min. vs. 43.5 ± 14.4 min.; p = 0.182). The overall hospital stay was significantly shorter in the MICLATS-AVR cohort (9.7 ± 5.2 days vs. 9.2 ± 4.5 days; p = 0.01). Both groups were comparable in terms of postoperative morbidities. However, significantly lower rates of postoperative impaired wound healing were noted in the MICLATS-AVR group (11.7% vs. 3.9%, p < 0.001); (4) Conclusions: In comparing MICLATS-AVR and RAT-AVR, our study found MICLATS-AVR to be at least as safe and time-efficient as RAT-AVR, with no significant differences in MACCE. MICLATS-AVR showed a shorter hospital stay and lower postoperative wound issues, indicating its feasibility and safety as an alternative. Notably, MICLATS-AVR is sternum- and bone-sparing, preserving the right mammary artery, and facilitates combined procedures like multiple valve surgeries.

The impact of two radical sternectomy surgical techniques on the outcome of deep sternal wound infections.

BACKGROUND: Deep sternal wound infection (DSWI) is a rare, yet devastating complication after cardiac surgery. While the surgical treatment always implies the soft tissue and bone debridement, there is little data about this procedure. The aim of our study was to evaluate the impact of the radical sternectomy on the outcome in patients with DSWI and to identify the risk factors which could influence the result. The surgical techniques of piecemeal sternectomy and the newly developed en bloc sternectomy were also evaluated. METHODS: The study was developed as a retrospective cohort study. 86 patients with DSWI who received a radical sternal resection at our institution between March 2018 and December 2021 were included. RESULTS: The average age of the cohort was 67.3 ± 7.4 years, and 23.3% of patients were female. The average length of stay trended shorter after en bloc sternectomy (median 26 days) compared to piecemeal sternectomy (37 days). There were no significant differences between the piecemeal and en bloc sternal resection techniques. Anticoagulant and antiplatelet drugs had no significant influence on bleeding and transfusion rates. Obese patients showed an increased risk for postoperative bleeding requiring reintervention. Transfusion of packed red blood cells was significantly associated with lower hemoglobin values before surgery and ASA Class 4 compared to ASA Class 3. The in-hospital mortality was 9.3%, with female sex and reintervention for bleeding as significant risk factors. Nine patients developed an infection relapse as a chronic fistula at the level of clavicula or ribs, with ASA Class 4 as a risk factor. CONCLUSION: Radical sternectomy is a safe procedure to treat DSWI with compromised sternal bone. Both piecemeal and en bloc techniques ensure reliable results, while complications and mortality appear to be patient-related.

Confirmation of Safety of Titanium Wire in Sternotomy Closure, A Randomized Prospective Study.

BACKGROUND: There are many factors that are known to increase the risk of sternal wound infection (SWI); some studies have reported that nickel is a risk factor for SWI. Titanium wires have only been used as an alternative to steel wires in patients with known allergy to nickel. However, there is a paucity of literature regarding the safety of using titanium wires compared to that on the safety of steel wires for sternum closure after cardiac surgery. Therefore, this study aimed to demonstrate the noninferiority of titanium wires, even in patients without a known allergy. METHODS: A total of 322 patients who underwent elective full median sternotomy were randomly assigned to sternal closure either by titanium wires (n = 161) or by stainless steel wires. RESULTS: Fourteen patients had sternal instability, six (3.7%) patients in the titanium group and eight (5%) patients in the stainless steel group (p = 0.585). There was no statistically significant difference between both groups in terms of postoperative wound infection (p = 0.147). Patients in the titanium group experienced statistically significant lower postoperative pain than those in the stainless steel group (p = 0.024). The wire type was not an independent risk factor for SI, as shown by univariate and logistic regression analyses. CONCLUSION: Titanium wires are a good alternative and have been proven to be safe and effective for sternal closure. The surgeon should be aware of the possibility of developing an allergic reaction to the wires, especially in patients with previous multiple allergic histories.

Living Longer or Better-Patient's Choice in Cardiac Surgery Is Gender-Dependent-A Multicenter Study.

In view of the increasing age of cardiac surgery patients, questions arise about the expected postoperative quality of life and the hoped-for prolonged life expectancy. Little is known so far about how these, respectively, are weighted by the patients concerned. This study aims to obtain information on the patients' preferences. Between 2015 and 2017, data were analyzed from 1349 consecutive patients undergoing cardiac surgery at seven heart centers in Germany. Baseline data regarding the patient's situation as well as a questionnaire regarding quality of life versus lifespan were taken preoperatively. Patients were divided by age into four groups: below 60, 60-70, 70-80, and above 80 years. As a result, when asked to decide between quality of life and length of life, about 60% of the male patients opted for quality of life, independent of their age. On the other hand, female patients' preference for quality of life increased significantly with age, from 51% in the group below sixty to 76% in the group above eighty years. This finding suggests that female patients adapt their preferences with age, whereas male patients do not. This should impact further the treatment decisions of elderly patients in cardiac surgery within a shared decision-making process.

Acquired Thrombocytopenia in Contemporary Transcatheter Aortic Valve Prosthesis.

BACKGROUND: Postprocedural thrombocytopenia is a known phenomenon following transcatheter aortic valve implantation (TAVI). The aim of this study is to evaluate whether postinterventional platelet kinetics differ when comparing the current generation of balloon-expandable valve (BEV) and self-expanding valve (SEV) prostheses. METHODS: We performed a retrospective analysis of patients undergoing TAVI at our facility between 2017 and 2019. Patients were stratified according to the type of prosthesis used: BEV or SEV. Hematocrit-corrected platelet counts were calculated to account for dilution. Nadir platelet counts (lowest recorded platelet count), drop platelet counts (DPC; highest relative platelet drop from baseline), and severity of thrombocytopenia during the discourse and at discharge were assessed. RESULTS: Of the 277 included patients, 212 received SEV and 65 BEV. BEV patients were younger (81.8 ± 4.4 years vs 79.7 ± 6.8 years, p = 0.03). Further demographic characteristics were similar between groups. Implanted SEV were larger (p < 0.001) and had shorter procedural times (p < 0.01). There were no significant differences in postprocedural discourse. Postinterventional platelet drop was more pronounced in BEV patients in several evaluated metrics: mean DPC (24.3 ± 10.9% vs 18.8 ± 14.8%, p < 0.01), patients with DPC > 30% (n = 19, 29.2%, vs n = 33, 15.6%, p = 0.02), and also when comparing platelet kinetics. CONCLUSION: Despite improvements in outcome, the current generation of balloon-expandable TAVI prostheses carries a predisposition for postprocedural thrombocytopenia even when the effects of dilution are accounted for.

Challenges of aortic valve tissue culture - maintenance of viability and extracellular matrix in the pulsatile dynamic microphysiological system.

BACKGROUND: Calcific aortic valve disease (CAVD) causes an increasing health burden in the 21st century due to aging population. The complex pathophysiology remains to be understood to develop novel prevention and treatment strategies. Microphysiological systems (MPSs), also known as organ-on-chip or lab-on-a-chip systems, proved promising in bridging in vitro and in vivo approaches by applying integer AV tissue and modelling biomechanical microenvironment. This study introduces a novel MPS comprising different micropumps in conjunction with a tissue-incubation-chamber (TIC) for long-term porcine and human AV incubation (pAV, hAV). RESULTS: Tissue cultures in two different MPS setups were compared and validated by a bimodal viability analysis and extracellular matrix transformation assessment. The MPS-TIC conjunction proved applicable for incubation periods of 14-26 days. An increased metabolic rate was detected for pulsatile dynamic MPS culture compared to static condition indicated by increased LDH intensity. ECM changes such as an increase of collagen fibre content in line with tissue contraction and mass reduction, also observed in early CAVD, were detected in MPS-TIC culture, as well as an increase of collagen fibre content. Glycosaminoglycans remained stable, no significant alterations of α-SMA or CD31 epitopes and no accumulation of calciumhydroxyapatite were observed after 14 days of incubation. CONCLUSIONS: The presented ex vivo MPS allows long-term AV tissue incubation and will be adopted for future investigation of CAVD pathophysiology, also implementing human tissues. The bimodal viability assessment and ECM analyses approve reliability of ex vivo CAVD investigation and comparability of parallel tissue segments with different treatment strategies regarding the AV (patho)physiology.

Minimally Invasive Isolated Aortic Valve Replacement in a Potential TAVI Cohort of Patients Aged ≥ 75 Years: A Propensity-Matched Analysis.

(1) Background and Objectives: Transcatheter aortic valve implantation is guideline-recommended from the age of 75. However, this European guideline recommendation is based on limited evidence, since no interaction between age and primary outcome has been found in guideline-stated references. This study aimed to compare the short-term outcomes of minimally invasive isolated aortic valve replacement in patients aged ≥ 75 with those of younger patients; (2) Patients and Methods: This retrospective cohort study included 1339 patients who underwent minimally invasive isolated aortic valve replacement at our facility between 2014 and 2022. This cohort was divided into two age-based groups: <75 and ≥75 years. Operative morbidity and mortality were compared between groups. Further analysis was performed using propensity score matching; (3) Results: After matching, 347 pairs of patients were included and analyzed. Despite the higher EuroSCORE II in the ≥75 group (2.2 ± 1.3% vs. 1.80 ± 1.34%, p ≤ 0.001), the 30-day mortality (1.4% vs. 1.2%; p = 0.90) and major adverse cardiac and cerebrovascular events, such as perioperative myocardial infarction (0.0% vs. 1.2%, p = 0.12) and stroke (1.4% vs. 2.6%, p = 0.06), were comparable between both treatment groups; (4) Conclusions: Minimally invasive aortic valve replacement is a safe treatment method for patients aged ≥ 75. Our results indicate that the unilateral cut-off of 75 years is not a limiting factor for performing minimally invasive aortic valve replacement.

The role of negative pressure wound therapy with instillation and dwell time in the treatment of deep sternal wound infections-A retrospective cohort study.

Background and Aims: Negative pressure wound therapy (NPWT) has gained a central role in the treatment of deep sternal wound infections (DSWIs) after median thoracotomy. Our study aims at proving the safety of using NPWT with instillation and dwell time (NPWTi-d) in the treatment of DSWI. Methods: We retrospectively evaluated the patients who were treated at our institution between March 2018 and November 2021 for DSWI after radical sternectomy using NPWT or NPWTi-d. The NPWTi-d was applied to start the first postoperative day using 75 mmHg negative pressure for 3 h, followed by instillation of sodium hypochlorite <0.08% with a 3-min dwell time. Results: The NPWTi-d group showed a shorter length of stay (29.39 ± 12.09 vs. 39.54 ± 17.07 days; p = 0.049), a shorter elapsed time between the debridement and the flap coverage (7.18 ± 4.27 vs. 11.86 ± 7.7 days; p = 0.003) and less operative or nonoperative dressing changes (1.73 ± 1.14 vs. 2.68 ± 56; p < 0.001). The in-hospital mortality was 8.2%, with no significant differences between the two groups (p = 1). Conclusion: NPWTi-d can be safely employed in the treatment of DSWI. Further prospective randomized studies need to establish the role of NPWTi-d in the control of infection and biofilm as well as in wound healing.

Pathological study of sternal osteomyelitis after median thoracotomy-a prospective cohort study.

PURPOSE: Osteomyelitis of the sternum may arise either as a primary condition or secondary to median thoracotomy after cardiac surgery, with the latter being decidedly more frequent. Deep sternal wound infections appear as a complication of median thoracotomy in 0.2 to 4.4% of cases and may encompass the infection of the sternal bone. To date, there are no exhaustive histopathological studies of the sternal osteomyelitis. METHODS: Our work group developed a surgical technique to remove the complete infected sternal bone in deep sternal wound infections. We therefore prospectively examined the en bloc resected sternal specimens. Seven standard histological sections were made from the two hemisternums. RESULTS: Forty-seven sternums could be investigated. The median age of the patients in the cohort was 66 (45-81) years and there were 10 females and 37 males. Two methods were developed to examine the histological findings, with one model dividing the results in inflammatory and non-inflammatory, while the second method using a score from 0 to 5 to describe more precisely the intensity of the bone inflammation. The results showed the presence of inflammation in 76.6 to 93.6% of the specimens, depending on the section. The left manubrial sections were more prone to inflammation, especially when the left mammary artery was harvested. No further risk factors proved to have a statistical significance. CONCLUSION: Our study proved that the deep sternal wound infection may cause a ubiquitous inflammation of the sternal bone. The harvest of the left mammary artery may worsen the extent and intensity of infection.

Microbiological study of sternal osteomyelitis after median thoracotomy - a retrospective cohort study.

INTRODUCTION: Deep sternal wound infection is a rare but feared complication of median thoracotomies and is usually caused by microorganisms from the patient's skin or mucous membranes, the external environment, or iatrogenic procedures. The most common involved pathogens are Staphylococcus aureus, Staphylococcus epidermidis and gram-negative bacteria. We aimed to evaluate the microbiological spectrum of deep sternal wound infections in our institution and to establish diagnostic and treatment algorithms. METHODS: We retrospectively evaluated the patients with deep sternal wound infections at our institution between March 2018 and December 2021. The inclusion criteria were the presence of deep sternal wound infection and complete sternal osteomyelitis. Eighty-seven patients could be included in the study. All patients received a radical sternectomy, with complete microbiological and histopathological analysis. RESULTS: In 20 patients (23%) the infection was caused by S. epidermidis, in 17 patients (19.54%) by S. aureus, in 3 patients (3.45%) by Enterococcus spp., in 14 patients (16.09%) by gram-negative bacteria, while in 14 patients (16.09%) no pathogen could be identified. In 19 patients (21,84%) the infection was polymicrobial. Two patients had a superimposed Candida spp. INFECTION: Methicillin-resistant S. epidermidis was found in 25 cases (28,74%), while methicillin-resistant S. aureus was isolated in only three cases (3,45%). The average hospital stay for monomicrobial infections was 29.93 ± 13.69 days and for polymicrobial infections was 37.47 ± 19.18 (p = 0.03). Wound swabs and tissue biopsies were routinely harvested for microbiological examination. The increasing number of biopsies was associated with the isolation of a pathogen (4.24 ± 2.22 vs. 2.18 ± 1.6, p < 0,001). Likewise, the increasing number of wound swabs was also associated with the isolation of a pathogen (4.22 ± 3.34 vs. 2.40 ± 1.45, p = 0.011). The median duration of antibiotic treatment was 24.62 (4-90) days intravenous and 23.54 (4-70) days orally. The length of antibiotic treatment for monomicrobial infections was 22.68 ± 14.27 days intravenous and 44.75 ± 25.87 days in total and for polymicrobial infections was 31.65 ± 22.29 days intravenous (p = 0.05) and 61.29 ± 41.45 in total (p = 0.07). The antibiotic treatment duration in patients with methicillin-resistant Staphylococci as well as in patients who developed an infection relapse was not significantly longer. CONCLUSION: S. epidermidis and S. aureus remain the main pathogen in deep sternal wound infections. The number of wound swabs and tissue biopsies correlates with accurate pathogen isolation. With radical surgical treatment, the role of prolonged antibiotic treatment remains unclear and should be evaluated in future prospective randomized studies.

Long-Term Outcomes after Transcatheter Mitral Valve-in-Valve or Valve-in-Ring Procedures.

BACKGROUND: Redo mitral valve surgery is the standard of care for failed mitral bioprostheses or recurrence of mitral regurgitation after repair. Nonetheless, catheter-based valve-in-valve (ViV) or valve-in-ring (ViR) procedures have increasingly become viable alternatives in high-risk subpopulations. Despite reported good initial results, little is known about longer-term outcomes. Here, we report the long-term outcomes of transcatheter mitral ViV and ViR procedures. METHODS: All consecutive patients (n = 54) undergoing transcatheter mitral ViV or ViR procedures for failed bioprostheses or recurring regurgitation after mitral repair in the time period between 2011 and 2021 were retrospectively enrolled. The mean age was 76.5 ± 6.5 years, and 30 (55.6%) of the patients were male. The procedures were done using a commercially available balloon-expandable transcatheter heart valve. Clinical and echocardiographic follow-up data were obtained from the hospital's database and analyzed. Follow-up reached up to 9.9 years with a total of 164.3 patient-years. RESULTS: A total 25 patients received a ViV and 29 patients a ViR procedure. Both groups were at high surgical risk with an STS-PROM of 5.9 ± 3.7% in ViV and 8.7 ± 9.0% in ViR patients (p < 0.01). The procedures themselves were mainly uneventful with no intraoperative deaths and a low conversion rate (n = 2/54; 3.7%). VARC-2 procedural success was low (ViV 20.0% and ViR 10.3%; p = 0.45), which was either driven by high rates of transvalvular pressure gradients ">5 mmHg" (ViV 92.0% and ViR 27.6%; p < 0.01) or residual regurgitation ">trace" (ViV 28.0% and ViR 82.7%; p < 0.01). ICU-stay was prolonged in both groups (ViV 3.8 ± 6.8 days and ViR 4.3 ± 6.3 days; p = 0.96) with acceptable hospital stay (ViV 9.9 ± 5.9 days and ViR 13.5 ± 8.0 days; p = 0.13). Despite 30-day mortality being acceptable (ViV 4.0% and ViR 6.9%; p = 1.00), the mean posthospital survival time was disappointingly low (ViV 3.9 ± 2.6 years and ViR 2.3 ± 2.7 years; p < 0.01). Overall survival in the entire group was 33.3%. Cardiac reasons for death were frequent in both groups (ViV 38.5% and ViR 52.2%). Cox-regression analysis identified ViR procedures as a predictor of mortality (HR 2.36, CI 1.19-4.67, p = 0.01). CONCLUSIONS: Despite acceptable immediate outcomes in this high-risk subpopulation, long-term results are discouraging. Transvalvular pressure gradients as well as residual regurgitations remained drawbacks in this real-world population. The indication for catheter-based mitral ViV or ViR procedures rather than conventional redo-surgery or conservative treatment must be thoughtfully considered.

Cardiac Surgery for Treatment of COVID-19-Associated Infectious Endocarditis.

BACKGROUND: Significant uncertainty exists about the optimal timing of surgery for infectious endocarditis (IE) surgery in patients with active SARS-CoV-2 infection. This case series and a systematic review of the literature were carried out to evaluate the timing of surgery and postsurgical outcomes for patients with COVID-19-associated IE. METHODS: The PubMed database was searched for reports published from June 20, 2020, to June 24, 2021, that contained the terms infective endocarditis and COVID-19. A case series of 8 patients from the authors' facility was also added. RESULTS: A total of 12 cases were included, including 4 case reports that met inclusion criteria in addition to a case series of 8 patients from the authors' facility. Mean (SD) patient age was 61.9 (17.1) years, and patients were predominantly male (91.7%). Being overweight was the main comorbidity among patients studied (7/8 [87.5%]). Among all patients evaluated in this study, dyspnea (n = 8 [66.7%]) was the leading symptom, followed by fever (n = 7 [58.3%]). Enterococcus faecalis and Staphylococcus aureus caused 75.0% of COVID-19-associated IE. The mean (SD) time to surgery was 14.5 (15.6) days (median, 13 days). In-hospital and 30-day mortality for all evaluated patients was 16.7% (n = 2). CONCLUSION: Clinicians must carefully assess patients diagnosed with COVID-19 to prevent missing underlying diseases such as IE. If IE is suspected, clinicians should avoid postponement of crucial diagnostic and treatment steps.

Aprotinin does not Impair Vascular Function in Patients Undergoing Coronary Artery Bypass Graft Surgery.

Bleeding is a major complication in coronary artery bypass graft surgery. Antifibrinolytic agents like serine protease inhibitor aprotinin can decrease postoperative bleeding and complications of cardiac surgery. However, the effects of aprotinin on vascular function are not completely elucidated. We compared the ex vivo vascular function of left internal mammary arteries from patients undergoing coronary artery bypass graft surgery with and without intraoperative application of aprotinin using a Mulvany Myograph. Human internal mammary arteries were treated with aprotinin ex vivo and tested for changes in vascular function. We analyzed the impact of aprotinin on vascular function in rat aortic rings. Finally, impact of aprotinin on expression and activity of endothelial nitric oxide synthase was tested in human endothelial cells. Intraoperative application of aprotinin did not impair ex vivo vascular function of internal mammary arteries of patients undergoing coronary artery bypass graft surgery. Endothelium-dependent and -independent relaxations were not different in patients with or without aprotinin after nitric oxide synthase blockade. A maximum vasorelaxation of 94.5%±11.4vs. 96.1%±5.5% indicated a similar vascular smooth muscle function in both patient groups (n=13 each). Long-term application of aprotinin under physiological condition preserved vascular function of the rat aorta. In vitro application of increasing concentrations of aprotinin on human endothelial cells resulted in a similar expression and activity of endothelial nitric oxide synthase. In conclusion, intraoperative and ex vivo application of aprotinin does not impair the endothelial function in human internal mammary arteries and experimental models.

Safety and Efficacy of the Transaxillary Access for Minimally Invasive Aortic Valve Surgery.

Background and Objectives: Transaxillary access is one of the latest innovations for minimally invasive aortic valve replacement (MICS-AVR). This study compares clinical performance in a large transaxillary MICS-AVR group to a propensity-matched sternotomy control group. Materials and Methods: This study enrolled 908 patients undergoing isolated AVR with a mean age of 69.4 ± 18.0 years, logistic EuroSCORE of 4.0 ± 3.9%, and body mass index (BMI) of 27.3 ± 6.1 kg/m2. The treatment group comprised 454 consecutive transaxillary MICS-AVR patients. The control group was 1:1 propensity-matched out of 3115 consecutive sternotomy aortic valve surgeries. Endocarditis, redo, and combined procedures were excluded. The multivariate matching model included age, left ventricular ejection fraction, logistic EuroSCORE, pulmonary hypertension, coronary artery disease, chronic lung disease, and BMI. Results: Propensity-matching was successful with subsequent comparable clinical baselines in both groups. MICS-AVR had longer skin-to-skin time (120.0 ± 31.5 min vs. 114.2 ± 28.7 min; p < 0.001) and more frequent bleeding requiring chest reopening (5.0% vs. 2.4%; p < 0.010), but significantly less packed red blood cell transfusions (0.57 ± 1.6 vs. 0.82 ± 1.6; p = 0.040). In addition, MICS-AVR patients had fewer access site wound abnormalities (1.5% vs. 3.7%; p = 0.038), shorter intensive care unit stays (p < 0.001), shorter ventilation times (p < 0.001), and shorter hospital stays (7.0 ± 5.1 days vs. 11.1 ± 6.5; p < 0.001). No significant differences were observed in stroke > Rankin 2 (0.9% vs. 1.1%; p = 0.791), renal replacement therapy (1.5% vs. 2.4%; p = 0.4762), and hospital mortality (0.9% vs. 1.5%; p = 0.546). Conclusions: Transaxillary MICS-AVR is at least as safe as AVR by sternotomy and can be performed in the same time frame. Its advantages are fewer transfusions and quicker postoperative recovery with a significantly shorter hospital stay. The cosmetic result and unrestricted physical abilities due to the untouched sternum and ribs are unique advantages of transaxillary access.

Pyoderma Gangrenosum after Cardiac Surgery.

BACKGROUND: Pyoderma gangrenosum after cardiac surgery is a rare, noninfectious ulcerating skin disease mimicking sternal wound infection. METHODS: A systematic search of literature for pyoderma gangrenosum complicating cases of cardiac surgery was conducted between September 1985 and September 2020 on PubMed and Cochrane databases. A systematic review and detailed overview of clinical presentation, diagnostic, treatment, and outcome is provided. RESULTS: A total of 15 studies enclosing 15 patients suffering from pyoderma gangrenosum following cardiac surgery were identified. Onset of symptoms was observed after a median of 5 days. Patients were predominantly male (81.3%) with a median age of 64 years. Typical clinical presentation mimicked sternal site infection, mainly by means of mediastinitis. Specific signs were rapid progression, erythematous to violaceous color of the wound border, accompanied by unspecific symptoms including fever, malaise, and severe pain. Additionally, pathergy (development of ulcers at the sites of minor cutaneous trauma) was reported frequently. Biopsy is mandatory with a cutaneous neutrophilic inflammation confirming the diagnosis. Initial treatment mostly (75.0% of reported cases) was misled, addressing suspicion of surgical site infection. After correct diagnosis, the treatment was switched to an immunosuppressive therapy. Full sternal wound closure took between 5 weeks and 5 months. Reported case mortality was 12.5% in actually low-risk surgeries. CONCLUSION: Despite pyoderma gangrenosum has typical signs, it remains an exclusion diagnosis. The treatment is completely opposite to the main differential diagnosis-the typical surgical site infection. Knowledge about diagnosis and treatment is essential in the context of avoiding fatal mistreatment.

Infrared Spectroscopic Verification of a α-Helical Collagen Structure in Glutaraldehyde-Free Crosslinked Bovine Pericardium for Cardiac Implants.

The degeneration of heart valve bioprostheses due to calcification processes is caused by the intercalation of calciumhydroxyapatite in pericardium collagen bundles. Variations of the protein secondary structure of biomaterials according to preparation are relevant for this mineralization process and thus the structural characterization of innovative bioprostheses materials is of great importance. The gold standard for prostheses preparation is glutaraldehyde (GA)-fixation of bovine pericardium that adversely promotes calcification. The novel GA-free SULEEI-treatment of bovine pericardium includes decellularization, UV-crosslinking, and electron beam sterilization. The aim of this study is the structural characterization of SULEEI-treated and GA-fixed bovine pericardium. IR spectroscopic imaging combined with multivariate data and curve fit analysis was applied to investigate the amide I and amide II regions of SULEEI-treated and GA-fixed samples. The spectroscopic images of GA-fixed pericardial tissue exhibited a generally high content of amine groups and side chains providing nucleation points for calcification processes. In contrast, in SULEEI-treated tissue, the typical α-helical structure was retained and was supposed to be less prone to deterioration.