Long-term outcomes following aortic valve replacement in bioprosthetic vs mechanical valves.

BACKGROUND: Aortic valve disease(AVD) accounts for 33 % of valvular heart disease(VHD) but causes over 60 % of VHD mortality. For surgical AVR, mechanical valves are recommended for patients <50 years old and bioprosthetic valves for those >70 years old. OBJECTIVES: To investigate the long-term differences following AV replacement(AVR) comparing bioprosthetic and mechanical valves in patients aged 50-70. METHODS: 4,927 patients underwent AVR, 744 of which were propensity-matched 2:1 for bioprosthetic and mechanical valves. Outcomes included mortality, morbidity, and rates of reoperation. RESULTS: The average age of the propensity-matched groups was 57 and 56.7 years, and female sex accounted for 26.4 % and 25.0 % for the bioprosthetic and mechanical valve groups, respectively. Other baseline demographics and comorbidities were similar between the groups. There were no deaths at 30 days and complication rates did not differ between groups(p > 0.05). Mortality at 1, 5, and 15 years was similar between groups. Reoperation rates at 5 and 10 years did not significantly differ between bioprosthetic and mechanical valves(p = 0.84, p = 0.31), although at 15-year follow-up, patients with bioprosthetic valves were more likely to require reoperation(21.2 % versus 9.7 %, adjusted hazard ratio 3.65, 95 % confidence interval 1.07-12.5, p = 0.0.39). CONCLUSIONS: Patients receiving AVR from 50 to 70 years old have similar long-term outcomes irrespective of whether they received bioprosthetic or mechanical valves, with only reoperation being significantly different at 15 years follow-up. With low rates of reoperation, mortality, and avoidance of anticoagulation, bioprosthetic valves are a reasonable option for patients 50-70 years old, although mechanical valves still provide a durability benefit for young patients.

Mitral valve surgery in octogenarians: long-term and hemodynamic results.

BACKGROUND: Octogenarians are often denied mitral valve (MV) surgery secondary to concerns over increased perioperative morbidity and mortality. The objective of this study was to examine the outcomes of octogenarians undergoing mitral valve repair (MVr) and replacement (MVR). METHODS: The outcomes of 139 patients between the ages of 80-90 who underwent MVR/MVr between 2004-2018 at the Mazankowski Alberta Heart Institute (Edmonton, AB, Canada) were retrospectively analyzed. Follow-up was extended to a maximum of 15.8 years. RESULTS: Following MVR, all-cause mortality at 30 days, 1 year, 5 years, 10 years, and the longest follow-up was 7%, 14%, 36.3%, 61.8%, and 67.7%, respectively. Post-MVr, all-cause mortality at the same time points was 1.9%, 7.6%, 22.5%, 55.5%, and 100%, respectively. During the Hospitalization Index, rates of new-onset atrial fibrillation, sepsis, acute kidney injury, superficial sternal wound infection, deep sternal wound infection, mediastinal bleeding, and permanent pacemaker insertion ranged from 22.1-34.0%, 3.8-11.0%, 7.6-22.0%, 1.9-2.4%, 0-1.2%, 0%, and 0-6.1%, respectively. Rates of overall rehospitalization, as well as readmission for heart failure, stroke, myocardial infarction, and MV reoperation ranged from 71.0-85.5%, 52.2-63.3%, 10.9-22.8%, 1.9-6.0%, and 0% during the follow-up period. There were significant reductions in peak MV gradient (P=0.042) and left ventricular internal diameter in diastole (LVIDd; P=0.008) post-MVR, as well as LVIDd (P<0.001) and Left Atrial (LA) Volume Index (P=0.019) post-MVr. CONCLUSIONS: Octogenarians exhibit positive left atrial and left ventricular remodeling following MVR. Perioperative morbidity is low, late survival is reasonable, and long-term morbidity is considerable. Overall, these results add to the growing literature that MV surgery is relatively safe and effective in octogenarians.

Perfusate Exchange Does Not Improve Outcomes in 24-hour Ex Situ Lung Perfusion.

BACKGROUND: Reliable 24-hour preservation is required to optimize the rehabilitation potential of Ex Situ Lung Perfusion (ESLP). Other ESLP protocols include fresh perfusate replacement to counteract an accumulation of deleterious by-products. We describe the results of our reliable 24-hour negative pressure ventilation (NPV)-ESLP protocol with satisfactory acute post-transplant outcomes and investigate perfusate exchange (PE) as a modification to enhance prolonged ESLP. METHODS: Twelve pig lungs underwent 24 hours of NPV-ESLP using 1.5L of cellular perfusate (500 mL packed red blood cells and 1 L buffered perfusate). The Control (n = 6) had no PE; the PE (n = 6) had 500 mL replaced after 12 hours of NPV-ESLP with 1000 mL fresh perfusate. Three left lungs per group were transplanted. RESULTS: Results are reported as Control vs PE (mean ± SEM). Both groups demonstrated stable and acceptable oxygenation during 24 hours of ESLP with final PF ratios of 527.5 ± 42.19 and 488.4 ± 35.38 (P = .25). Final compliance measurements were 20.52 ± 3.59 and 18.55 ± 2.91 (P = .34). There were no significant differences in pulmonary artery pressure after 24 hours of ESLP (10.02 ± 2.69 vs 14.34 ± 1.64, P = .10), and pulmonary vascular resistance only differed significantly at T12 (417.6 ± 53.06 vs 685.4 ± 81.19, P = .02). Percentage weight gain between groups was similar (24.32 ± 8.4 and 45.33 ± 7.76, P = .07). Post-transplant left lung oxygenation was excellent (327.3 ± 14.62 and 313.3 ± 15.38, P = .28). There was no significant difference in % weight gain of lungs post-transplant (22.20 ± 7.22 vs 14.36 ± 9.96, P = .28). CONCLUSION: Acceptable lung function was maintained during 24-hour NPV-ESLP and post-transplant regardless of PE.

Moderate-Flow Perfusion is Superior to Low-Flow Perfusion in Ex Situ Lung Perfusion.

BACKGROUND: Full-flow perfusion during prolonged ex situ lung perfusion (ESLP) results in unacceptable pulmonary edema formation. Clinical ESLP at 30% to 50% predicted cardiac output (CO) supports acceptable physiologic outcomes; however, progressive pulmonary edema still develops. Lower flow rates may provide equivalent physiologic preservation with less edema formation due to reduced hydrostatic pressures. We report our results of moderate-flow (MF; 30% CO) vs low-flow (LF; 10% CO) negative pressure ventilation (NPV)-ESLP with transplantation. METHODS: Twelve pig lungs underwent 12-hours of NPV-ESLP with 30% or 10% CO (n = 6/group). Three left lungs per group were transplanted post-ESLP and assessed in vivo over 4 hours. Lung function was assessed by physiologic parameters, weight-gain, and pro-inflammatory cytokine profiles. RESULTS: Results are MF vs LF (mean ± SEM). All lungs demonstrated acceptable oxygenation post-ESLP (454.2 ± 40.85 vs 422.7 ± 31.68, P = .28); however, after transplantation, the MF lungs demonstrated significantly better oxygenation (300.7 ± 52.26 vs 141.9 ± 36.75, P = .03). There was no significant difference in compliance after ESLP (21.38 ± 2.28 vs 16.48 ± 2.34, P = .08); however, pulmonary artery pressure (PAP; 10.89 ± 2.28 vs 21.11 ± 0.93, P = .06) and pulmonary vascular resistance (PVR; 438.60 ± 97.97 vs 782.20 ± 162.20, P = .05) were significantly higher in the LF group. Weight gain (%) post-ESLP and post-transplant was similar between groups (29.42 ± 5.72 vs 24.17 ± 4.42, P = .24; and 29.63 ± 7.23 vs 57.04 ± 15.78, P = .09). TNF-α and IL-6 were significantly greater throughout LF ESLP. CONCLUSIONS: The MF NPV-ESLP results in superior lung function with less inflammation compared to LF NPV-ESLP.

Anomalous coronary artery masquerading as a root abscess: a case report.

Congenital coronary artery anomalies are rare and most often clinically benign. We present a case of a 67-year-old male with osteomyelitis and persistent bacteremia with an anomalous left coronary artery mimicking an aortic root abscess. A transesophageal echocardiogram revealed a hypoechoic potential space around the aortic root, highly suspicious for a root abscess. Urgent cardiac surgery was performed, revealing no infection but an anomalous coronary artery arising from the right coronary sinus. This case highlights the importance of considering atypical anatomy in the diagnosis of infectious cardiac processes. While this resemblance should not delay intervention for suspected abscesses, it emphasizes the need to be aware of congenital differences in imaging for patients with known anomalies or asymptomatic patients with unknown anatomy.

Abnormal coronary arteries are rare and are usually not dangerous. We present a case of a 67-year-old male with an infection in the bone and persistent findings of bacteria in the blood who had an abnormal coronary artery that mimicked an infected space. Ultrasound of the heart found thickening and a space around the aortic root, highly suspicious for an infection in the setting of bacteria in the blood. Urgent surgery was performed, revealing no signs of infection but abnormal coronary artery anatomy. This case highlights the importance of considering atypical anatomy in the diagnosis of infection around the heart. While this should not delay intervention, it emphasizes the need to be aware of differences in anatomy.

Normothermic Perfusion is Superior to Cold Perfusion in Porcine Ex Situ Lung Perfusion.

BACKGROUND: Cold ex situ lung perfusion (ESLP) has demonstrated improved preservation in small animal ESLP compared to normothermic ESLP and cold static preservation. We hypothesized that cold negative pressure ventilation (NPV)-ESLP would improve graft function in a porcine transplantation model. METHODS: Four perfusate temperatures were examined with 12 hours NPV-ESLP in a large animal transplantation model. Pig lungs were allotted to four groups: (1) Normothermia (38°C, n = 6); (2) profound hypothermia (10°C, n = 6); (3) moderate hypothermia (20°C, n = 3); (4) subnormothermia (32°C, n = 3). A fifth group subnormothermic low-flow (SNLF) perfusion was examined to assess the effect of reduced cardiac output with cold perfusion (32°C, 10% cardiac output, n = 6). RESULTS: Only Normothermic and SNLF groups demonstrated acceptable oxygenation after 12 hours NPV-ESLP and were transplanted. All other groups failed prematurely. After 12 hours of ESLP, Normothermic lungs demonstrated significantly greater dynamic compliance compared to SNLF lungs (P = .03). Edema formation post-ESLP was significantly worse in the SNLF group (P = .01). There was no significant difference in pulmonary artery pressures after ESLP (P = .10); however, pulmonary vascular resistance was significantly greater in the SNLF (P = .04). Isolated left lung oxygenation 4-hours post-transplant and left lung edema formation was not significantly different between Normothermic and SNLF post-transplant (P = .09). Proinflammatory cytokines were significantly greater during SNLF-ESLP (tumor necrosis factor alpha, P < .05). CONCLUSIONS: Prolonged normothermic (38°C) NPV-ESLP is superior to 10, 20, and 32°C perfusion. Normothermic ESLP of porcine lungs results in superior graft function and reduced inflammation versus SNLF-ESLP.

Impact of Sex on Long-Term Outcomes Following Surgical Aortic Valve Replacement.

BACKGROUND: The impact of sex on outcomes following surgical aortic valve replacement (SAVR) remains unclear. It has been proposed that females experience inferior outcomes, but this has yet to be conclusively established, particularly in the long term. The objective of this study is to identify discrepancies in postoperative outcomes between males and females following SAVR to better inform consideration for surgical intervention. METHOD: We retrospectively reviewed the outcomes of 4,927 patients who underwent SAVR from 2004 to 2018 at our centre. In total, 531 propensity-matched males and females were included in the final analysis. The primary outcome was mortality at any point during the follow-up period. Secondary outcomes included various measures of postoperative morbidity. Follow-up duration was 15 years. RESULTS: In SAVR all-comers, females experienced inferior short-term mortality, but equivalent mid-term and long-term mortality. Rates of mediastinal bleeding, sternal wound infections, sepsis, heart failure, and pacemaker insertion were all equivalent between the sexes; however, males experienced a higher rate of acute kidney injury and readmission for stroke at the longest follow-up while females experienced a longer intensive care unit and hospital length of stay. In a sub-analysis of isolated SAVR, males and females experienced equivalent early, mid, and late mortality. Of note, a trend towards increased aortic valve reoperation was noted in females at the longest follow-up. CONCLUSIONS: Males and females experience equivalent long-term mortality following isolated SAVR. Sex is not an independent risk factor of poor outcomes post-SAVR; however, the increased preoperative risk profile of females requires diligent consideration.

The Effects of Oxygen-Derived Free-Radical Scavengers During Normothermic Ex-Situ Heart Perfusion.

Oxidative stress occurs during ex-situ heart perfusion (ESHP) and may negatively affect functional preservation of the heart. We sought to assess the status of key antioxidant enzymes during ESHP, and the effects of augmenting these antioxidants on the attenuation of oxidative stress and improvement of myocardial and endothelial preservation in ESHP. Porcine hearts were perfused for 6 hours with oxygen-derived free-radical scavengers polyethylene glycol (PEG)-catalase or PEG-superoxide dismutase (SOD) or with naive perfusate (control). The oxidative stress-related modifications were determined in the myocardium and coronary vasculature, and contractile function, injury, and endothelial integrity were compared between the groups. The activity of key antioxidant enzymes decreased and adding catalase and SOD restored the enzyme activity. Cardiac function and endothelial integrity were preserved better with restored catalase activity. Catalase and SOD both decreased myocardial injury and catalase reduced ROS production and oxidative modification of proteins in the myocardium and coronary vasculature. The activity of antioxidant enzymes decrease in ESHP. Catalase may improve the preservation of cardiac function and endothelial integrity during ESHP. While catalase and SOD may both exert cardioprotective effects, unbalanced SOD and catalase activity may paradoxically increase the production of reactive species during ESHP.

Impact of the COVID-19 pandemic on esophageal cancer resource allocation: a systematic review.

Background: The coronavirus disease 2019 (COVID-19) pandemic challenged global infrastructure. Healthcare systems were forced to reallocate resources toward the frontlines. In this systematic review, we analyze the impact of resource reallocation during the COVID-19 pandemic on the diagnosis, management, and outcomes of esophageal cancer (EC) patients. Methods: PubMed and Embase were systematically searched for articles investigating the impact of the COVID-19 pandemic on EC patients. Of the 1,722 manuscripts initially screened, 23 met the inclusion criteria. Results: Heterogeneity of data and outcomes reporting prohibited aggregate analysis. Reduced detection of EC and considerable variability in disease stage at presentation were noted during the COVID-19 pandemic. EC patients experienced delays in diagnostic and preoperative staging investigations but surgical resection was not associated with greater short-term morbidity or mortality. Modeling the impact of pandemic-related delays in EC care predicts significant reductions in survival with associated economic losses in the coming years. Conclusions: Amidst resource scarcity during the COVID-19 pandemic, the multidisciplinary management of patients with EC was affected at multiple stages in the care pathway. Although the complete ramifications of reductions in EC diagnosis and delays in care remain unclear, EC surgery was able to safely continue as a result of collaboration between centers, strict adherence to COVID-19 protective measures, and reallocation of healthcare resources towards the same. Ultimately, when healthcare systems are pushed to the brink, the downstream consequences of resource reallocation require judicious analysis to optimize overall patient outcomes.

Relation of body mass index to long-term survival and cardiac remodelling for patients undergoing mitral valve replacement surgery.

BACKGROUND AND AIMS: Studies have demonstrated that obesity is paradoxically associated with reduced mortality following cardiac surgery. However, these studies have treated various types of cardiac surgery as a single entity. With mitral valve (MV) surgeries being the fastest-growing cardiac surgical interventions in North America, the purpose of this study was to identify the impact of body mass index (BMI) on long-term survival and cardiac remodelling of patients undergoing MV replacement (MVR). METHODS AND RESULTS: In this retrospective, single-center study, 1071 adult patients who underwent an MVR between 2004 and 2018 were stratified into five BMI groups (<20, 20-24.9, 25-29.9, 30-34.9, >35). Cox proportional hazard regression models were used to determine the association between BMI and all-cause mortality. Patients who were underweight had significantly higher all-cause mortality rates at the longest follow-up (median 8.2 years) than patients with normal weight (p = 0.01). Patients who were in the obese group had significantly higher readmission rates due to myocardial infarction (MI) at the longest follow-up (p = 0.017). Subgroup analysis revealed a significant increase in long-term all-cause mortality for female patients who were underweight. Significant changes in left atrial size, mitral valve peak and mean gradients were seen in all BMI groups. CONCLUSIONS: For patients undergoing mitral valve replacement, BMI is unrelated to operative outcomes except for patients who are underweight.

Randomized trial of routine versus on-demand intraoperative extracorporeal membrane oxygenation in lung transplantation: A feasibility study.

In most centers, extracorporeal membrane oxygenation (ECMO) is the preferred means to provide cardiopulmonary support during lung transplantation. However, there is controversy about whether intraoperative venoarterial (VA) ECMO should be used routinely or selectively. A randomized controlled trial is the best way to address this controversy. In this publication, we describe a feasibility study to assess the practicality of a protocol comparing routine versus selective VA-ECMO during lung transplantation. This prospective, single-center, randomized controlled trial screened all patients undergoing lung transplantation. Exclusion criteria include retransplantation, multiorgan transplantation, and cases where ECMO is mandatory. We determined that the trial would be feasible if we could recruit 19 participants over 6 months with less than 10% protocol violations. Based on the completed feasibility study, we conclude that the protocol is feasible and safe, giving us the impetus to pursue a multicenter trial with little risk of failure due to low recruitment.

The Use of Sodium-Glucose Cotransporter-2 Inhibitors in Coronary Revascularization: Where Are We Now? A Systematic Review.

INTRODUCTION: Diabetes and coronary artery disease are two common conditions that often co-exist. In recent years, sodium-glucose cotransporter 2 inhibitors (SGLT2i) have been demonstrated to provide significant cardioprotective benefits, especially among patients with heart failure. OBJECTIVE: In this systematic review, we look to identify the outcomes SGLT2i use in patients undergoing coronary revascularization. METHODS: Pubmed and Embase were systematically searched for articles describing the outcomes of patients taking SGLT2i and undergoing coronary revascularization. 834 titles and abstracts were screened, 42 full texts were reviewed, and 18 studies were found to meet the inclusion criteria and were included in this review. RESULTS: For patients undergoing coronary artery bypass grafting and percutaneous coronary intervention, the use of SGLT2i resulted in reductions in mortality, hospitalization for heart failure, and improved blood glucose; however, these benefits were not consistently reported in the literature. Reduced inflammatory markers and positive cardiac remodeling were identified among patients taking SGLT2i. CONCLUSIONS: Sodium-glucose cotransporter 2 inhibitors (SGLT2i) have been demonstrated to provide benefits for patients with heart failure along with a host of positive modulatory effects on the cardiovascular system, including reductions in inflammatory properties, hypertension, and left ventricular volume load. Given the clear benefit provided by SGLT2i to patients with cardiovascular disease and a host of positive properties that are expected to be protective for patients with ischemic heart disease, future investigation into the relationship between SGLT2i and outcomes for patients undergoing revascularization is imperative.

Resource allocation during the coronavirus disease 2019 pandemic and the impact on patients with lung cancer: a systematic review.

OBJECTIVES: The coronavirus disease 2019 (COVID-19) pandemic resulted in unprecedented tolls on both economies and human life. Healthcare resources needed to be reallocated away from the care of patients and towards supporting the pandemic response. In this systematic review, we explore the impact of resource allocation during the COVID-19 pandemic on the screening, diagnosis, management and outcomes of patients with lung cancer during the pandemic. METHODS: PubMed and Embase were systematically searched for articles investigating the impact of the COVID-19 pandemic on patients with lung cancer. Of the 1605 manuscripts originally screened, 47 studies met the inclusion criteria. RESULTS: Patients with lung cancer during the pandemic experienced reduced rates of screening, diagnostic testing and interventions but did not experience worse outcomes. Population-based modelling studies predict significant increases in mortality for patients with lung cancer in the years to come. CONCLUSIONS: Reduced access to resources during the pandemic resulted in reduced rates of screening, diagnosis and treatment for patients with lung cancer. While significant differences in outcomes were not identified in the short term, ultimately the effects of the pandemic and reductions in cancer screening will likely be better delineated in the coming years. Future consideration of the long-term implications of resource allocation away from patients with lung cancer with an attempt to provide equitable access to healthcare and limited interruptions of patient care may help to provide the best care for all patients during times of limited resources.

Aging Is Associated With Organ-Specific Alterations in the Level and Expression Pattern of von Willebrand Factor.

BACKGROUND: VWF (von Willebrand factor) is an endothelial-specific procoagulant protein with a major role in thrombosis. Aging is associated with increased circulating levels of VWF, which presents a risk factor for thrombus formation. METHODS: Circulating plasma, cellular protein, and mRNA levels of VWF were determined and compared in young and aged mice. Major organs were subjected to immunofluorescence analyses to determine the vascular pattern of VWF expression and the presence of platelet aggregates. An in vitro model of aging, using extended culture time of endothelial cells, was used to explore the mechanism of age-associated increased VWF levels. RESULTS: Increased circulating plasma levels of VWF with elevated levels of larger multimers, indicative of VWF functional activity, were observed in aged mice. VWF mRNA and cellular protein levels were significantly increased in the brains, lungs, and livers but not in the kidneys and hearts of aged mice. Higher proportion of small vessels in brains, lungs, and livers of aged mice exhibited VWF expression compared with young, and this was concomitant with increased platelet aggregate formation. Prolonged culture of endothelial cells resulted in increased cell senescence that correlated with increased VWF expression; VWF expression was specifically detected in senescent cultured endothelial cells and abolished in response to p53 knockdown. A significantly higher proportion of VWF expressing endothelial cells in vivo exhibited senescence markers SA-ß-Gal (senescence-associated ß-galactosidase) and p53 in aged mouse brains compared with that of the young. CONCLUSIONS: Aging elicits a heterogenic response in endothelial cells with regard to VWF expression, leading to organ-specific increase in VWF levels and alterations in vascular tree pattern of expression. This is concomitant with increased platelet aggregate formation. The age-associated increase in VWF expression may be modulated through the process of cell senescence, and p53 transcription factor contributes to its regulation.

Relative Lung Perfusion on Ventilation-Perfusion Scans After Double Lung Transplant.

BACKGROUND: Pulmonary blood flow can be assessed on ventilation-perfusion (VQ) scan with relative lung perfusion, with a 55% to 45% (or 10%) right-to-left differential considered normal. We hypothesized that wide perfusion differential on routine VQ studies at 3 mo posttransplant would be associated with an increased risk of death or retransplantation, chronic lung allograft (CLAD), and baseline lung allograft dysfunction. METHODS: We conducted a retrospective cohort study on all patients who underwent double-lung transplant in our program between 2005 and 2016, identifying patients with a wide perfusion differential of >10% on a 3-mo VQ scan. We used Kaplan-Meier estimates and proportional hazards models to assess the association between perfusion differential and time to death or retransplant and time to CLAD onset. We used correlation and linear regression to assess the relationship with lung function at time of scan and with baseline lung allograft dysfunction. RESULTS: Of 340 patients who met inclusion criteria, 169 (49%) had a relative perfusion differential of ≥ 10% on a 3-mo VQ scan. Patients with increased perfusion differential had increased risk of death or retransplantation ( P = 0.011) and CLAD onset ( P = 0.012) after adjustment for other radiographic/endoscopic abnormalities. Increased perfusion differential was associated with lower lung function at time of scan. CONCLUSIONS: Wide lung perfusion differential was common after lung transplant in our cohort and associated with increased risk of death, poor lung function, and CLAD onset. The nature of this abnormality and its use as a predictor of future risk warrant further investigation.

The impact of resource allocation during the COVID-19 pandemic on cardiac surgical practice and patient outcomes: a systematic review.

OBJECTIVES: The coronavirus disease 2019 (COVID-19) pandemic has shaken the world and placed enormous strain on healthcare systems globally. In this systematic review, we investigate the effect of resource allocation on cardiac surgery programs and the impact on patients awaiting elective cardiac surgery. METHODS: PubMed and Embase were systematically searched for articles published from 1 January 2019 to 30 August 2022. This systematic review included studies investigating the impact of the COVID-19 pandemic on resource allocation and the subsequent influence on cardiac surgery outcomes. A total of 1676 abstracts and titles were reviewed and 20 studies were included in this review. RESULTS: During the COVID-19 pandemic, resources were allocated away from elective cardiac surgery to help support the pandemic response. This resulted in increased wait times for elective patients, increased rates of urgent or emergent surgical intervention and increased rates of mortality or complications for patients awaiting or undergoing cardiac surgery during the pandemic. CONCLUSIONS: While the finite resources available during the pandemic were often insufficient to meet the needs of all patients as well as the influx of new COVID-19 patients, resource allocation away from elective cardiac surgery resulted in prolonged wait times, more frequent urgent or emergent surgeries and negative impacts on patient outcomes. Understanding the impacts of delayed access to care with regards to urgency of care, increased morbidity and mortality and increased utilization of resources per indexed case needs to be considered to navigate through pandemics to minimize the lingering effects that continue to negatively impact patient outcomes.

Persistent methicillin-resistant Staphylococcus aureus bacteremia from an infected superior vena cava thrombus.

Infection is among the leading causes of mortality for patients with end-stage renal disease. The placement of catheters for hemodialysis are common culprits of infection and have been associated with the development of complications such as venous thrombosis, bacteremia and thromboembolism. Calcification of a venous thrombus is a rare complication and infection of a right-sided thrombus can result in life-threatening septicemia and embolic complications. Herein, we describe the case of a 46-year-old patient found to have a calcified superior vena cava thrombus and bacteremia refractory to antibiotic therapy requiring surgical intervention under circulatory arrest to remove the infected thrombus gaining infectious source control and preventing future complications.

Infection is among the leading causes of mortality for patients with end-stage renal disease. The placement of catheters for dialysis are common culprits of infection and have been associated with the development of complications such as blood clotting in the veins and bacteria in the blood. Calcification of a venous blood clot is a rare complication and infection of a venous blood clot can result in life-threatening blood stream infection and dislodgement of clots. Herein, we describe the case of a 46-year-old patient found to have a calcified superior vena cava clot and a blood stream infection resistant to antibiotic therapy requiring surgical intervention to remove the infected clot gaining infectious source control and preventing future complications.

Anomalous left anterior descending coronary artery arising from the right coronary artery: a case report.

Congenital anomalous coronary artery origins are rare, with a prevalence of 0.24-1.6%. Common configurations include left circumflex arising from the right coronary (RCA), left main coronary arising from the right coronary sinus and independent ostia for the left anterior descending (LAD) and left circumflex. One rare configuration that is not well described is the LAD arising from the RCA. A 68-year-old patient presented with non-ST elevation myocardial infarction, underwent coronary artery bypass grafting and was found to have a patent LAD arising from the RCA. In patients presenting with coronary artery disease and anomalous coronary anatomy, careful preoperative planning and intraoperative attention to patient anatomy is essential in identifying high-risk coronary anomalies and providing the correct and optimal treatments for these patients.

Abnormal origins of the heart arteries are rare, affecting an estimated 0.24­1.6% of the general population. The two main coronary arteries are the right coronary artery (RCA) and left main coronary artery, which branches into the left anterior descending (LAD) and left circumflex artery. While several configurations have been described, one exceedingly rare configuration is the LAD arising from the RCA. A 68-year-old patient presenting with an acute coronary event undergoing coronary artery bypass grafting was found to have an LAD arising from the RCA. Patients presenting with coronary artery disease and abnormal coronary anatomy require careful preoperative planning and intraoperative attention to patient anatomy to identify high-risk coronary abnormalities and providing the optimal treatments for these patients.

Quantifying the immune response to a tissue-engineered porcine extracellular matrix.

Aim: Structural valvular deterioration of xenogenic heart valve replacements is thought to be due to a chronic immune response. We sought to engineer porcine extracellular matrix that elicits minimal inflammatory immune response. Materials & methods: Whole blood, bone marrow and pericardium were collected from patients undergoing elective cardiac surgery. Porcine extracellular matrix was decellularized, reseeded with homologous mesenchymal stem cells and exposed to whole blood. Results: DAPI stain confirmed the absence of cells after decellularization, and presence of mesenchymal stem cells after recellularization. There was a significant reduction in IL-1ß and TNF-α production in the recellularized matrix. Conclusion: Recellularization of porcine matrix is successful at attenuating the xenogenic immune response and may provide a suitable scaffold to address the current limitations of prosthetic heart valve replacements.

Deterioration of tissue heart valve replacements is thought to be due to a chronic immune response. We sought to remove cells from a pig derived tissue and replace those cells with human stem cells to create a scaffold that results in a reduced immune response. Whole blood, bone marrow and pericardium were collected from patients undergoing elective cardiac surgery. The pig derived tissue had the cells removed, were replaced with human stem cells and exposed to whole blood. Tissue stain confirmed the absence of cells after removal, and presence of stem cells after replacement of cells. There was a significant reduction in markers of immune response in the recellularized tissue. Removal of cells from pig derived tissue and replacement with human stem cells is successful at reducing the immune response to animal tissue and may provide a suitable scaffold to address the current limitations of heart valve replacement options.