The Association of Oxygen Delivery and Transfusion on Cardiopulmonary Bypass with Acute Kidney Injury.

OBJECTIVES: To estimate whether the association of transfusion and acute kidney injury (AKI) has a threshold of oxygen delivery below which transfusion is beneficial but above which it is harmful. DESIGN: Retrospective study SETTING: Cardiovascular operating room and intensive care unit PARTICIPANTS: Patients undergoing cardiac surgery with continuous oxygen delivery monitoring during cardiopulmonary bypass INTERVENTIONS: None MEASUREMENTS AND MAIN RESULTS: Logistic regression was used to estimate the associations between oxygen delivery (mean, cumulative deficit, and bands of oxygen delivery), transfusion, and their interaction and AKI. A subgroup analysis of transfused and nontransfused patients with exact matching on cumulative oxygen deficit and time on bypass with adjustment for propensity to receive a transfusion using logistic regression. Nine hundred ninety-one of 4,203 patients developed AKI within 7 days. After adjustment for confounders, lower mean oxygen delivery (odds ratio [OR], 0.968; 95% confidence interval [CI], 0.949-0.988; p = 0.002) and transfusions (OR, 1.442; 95% CI, 1.077, 1.932; p = 0.014) were associated with increased odds of AKI by 7 days. As oxygen delivery decreased, the risk of AKI increased, with the slope of the OR steeper at <160 mL/m2/min. In the subgroup analysis, matched transfused patients were more likely than matched nontransfused patients to develop AKI (45% [n = 145] v 31% [n = 101]; p < 0.001). However, after propensity score adjustment, the difference was nonsignificant (OR, 1.181; 95% CI, 0.796-1.752; p = 0.406). CONCLUSIONS: We found a nonlinear relationship between oxygen delivery and AKI. We found no level of oxygen delivery at which transfusion was associated with a decreased risk of AKI.

Pulmonary Hypertension and Operative Risk in Mitral Valve and Coronary Surgery.

INTRODUCTION: Pulmonary hypertension (PHT) is a known risk factor for coronary artery bypass grafting (CABG), though less well understood for valve operations. We hypothesized PHT is associated with lower risk during mitral valve operations compared to CABG. METHODS: Patients undergoing isolated mitral valve or CABG operations (2011-2019) in a regional Society of Thoracic Surgeons (STS) database were stratified by pulmonary artery systolic pressure (PASP). The association of PASP by procedure type was assessed by hierarchical regression modeling, adjusting for STS predicted risk scores. RESULTS: Of the 2542 mitral and 11,059 CABG patients, the mitral population had higher mean STS risk of mortality (3.6% versus 2.4%, P < 0.0001) and median PASP (42 mmHg versus 32 mmHg, P < 0.0001). PASP was independently associated with operative mortality and major morbidity in both mitral and CABG patients. However, for mitral patients a 10-mmHg increase in PASP was associated with lower odds of morbidity (odds ratio: 1.06 versus 1.13), mortality (odds ratio: 1.11 versus 1.18) and intensive care unit time (4.3 versus 7.6 h) compared with CABG patients (interaction terms P < 0.0001). Among mitral patients, median PASP was higher in stenotic versus regurgitant disease (57 mmHg versus 40 mmHg, P < 0.0001). However, there was no differential association of PASP on morbidity or mortality (interaction terms P > 0.05). CONCLUSIONS: Although mitral surgery patients tend to have higher preoperative pulmonary artery pressures, PHT was associated with a lower risk for mitral outcomes compared with CABG. Further research on the management and optimization of patients with PHT perioperatively is needed to improve care for these patients.

Temporal Cluster Analysis of Deep Sternal Wound Infection in a Regional Quality Collaborative.

INTRODUCTION: Deep sternal wound infection (DSWI) is a rare complication associated with high mortality. Seasonal variability in surgical site infections has been demonstrated, however, these patterns have not been applied to DSWI. The purpose of this study was to assess temporal clustering of DSWIs. METHODS: All cardiac surgery patients who underwent sternotomy were queried from a regional Society of Thoracic Surgeons database from 17 centers from 2001 to 2019. All patients with the diagnosis of DSWI were then identified. Cluster analysis was performed at varying time intervals (monthly, quarterly, and yearly) at the hospital and regional level. DSWI rates were calculated by year and month, and compared using mixed-effects negative binomial regression. RESULTS: A total of 134,959 patients underwent a sternotomy for cardiac surgery, of whom 469 (0.35%) developed a DSWI. Rates of DSWI per hospital across all years ranged from 0.12% to 0.69%. Collaborative-level rates of DSWIs were the greatest in September (0.44%) and the lowest in January (0.30%). Temporal clustering was not seen across seasonal quarters (high rate in preceeding quarter was not associated with a high rate in the next quarter) (P = 0.39). There were yearly differences across all institutions in the DSWI rates. A downward trend in DSWI rates was seen from 2001 to 2019 (P < 0.001). A difference among hospitals in the cohort was observed (P < 0.001). CONCLUSIONS: DSWI are a rare event within our region. Unlike other surgical site infection, there does not appear to be a seasonal pattern associated with DSWI.

Access to Left Ventricular Assist Device: Travel Time Does Not Tell The Whole Story.

BACKGROUND: Negative health effects of traveling longer distances for surgical services have been reported. Given the high complexity of multidisciplinary care required for management of Left Ventricular Assist Device (LVAD) implantation, only 4 of 18 centers in our state perform these operations. Given the limited access we hypothesized increased travel time would adversely affect postoperative outcomes and 30-d mortality. METHODS: A statewide Society of Thoracic Surgeons database was queried to identify patients undergoing Heartmate II/III and HVAD implantation, and 725 patients were identified. Travel time was calculated by zip code. Patients were stratified into regional and distant groups by the upper quartile of travel time (1-h). Preoperative variables and outcomes were compared between the groups. Multivariate analysis was performed to evaluate the impact of travel time in risk-adjusted models of 30-d mortality. RESULTS: Median patient travel time to their LVAD center in our state is 32 min (mean 53 ± 65 min, 46 ± 71 miles). Patients in the distant group (n = 191) had lower median incomes, higher self-pay status, higher rates of medical comorbid disease. Despite these differences there was no difference between the groups in ICU and/or hospital length of stay, readmission, postoperative complications, or 30-d mortality. Multivariate regression demonstrated insurance status, age, and prior surgery predicted 30-d mortality, but not travel time. CONCLUSIONS: Despite only four centers in the state performing LVAD implantation, travel time was strongly associated with preoperative risk, and socioeconomic status but not postoperative outcomes or 30-d mortality. Therefore, increasing access should focus on insurance, and patient characteristics not travel time.

Genetic and Pharmacological Disruption of Interleukin-1α Leads to Augmented Murine Aortic Aneurysm.

BACKGROUND: Interleukin-1 (IL-1) signaling has an established role as a cytokine signaling pathway important for progression of abdominal aortic aneurysms (AAAs). While the IL-1ß ligand and IL-1R1 have been previously investigated, the role of the IL-1α ligand in AAAs remains unknown. In this study, we sought to examine the role of IL-1α in AAAs using genetic and pharmacologic approaches. METHODS: Eight-week-old wild-type (WT) or IL-1α knock-out (KO) male and female mice (n = 10-16/group) underwent experimental AAA and were harvested 14 days following surgery to assess AAA size and characteristics. In separate studies, 8-week-old WT mice were treated with an inhibitor to IL-1α during AAA formation and harvested 14 days following surgery. Finally, WT and IL-1α KO mice were administered Anakinra, an IL-R1 inhibitor, during AAA formation to determine the effect of inhibiting IL-1R1 when IL-1α is knocked out. RESULTS: Male and female IL-1α KO mice had larger AAAs compared to WT AAAs (male: 153% vs. 89.2%, P = 0.0001; female: 86.6% vs. 63.5%, P = 0.02). IL-1α KO mice had greater elastin breakage (P = 0.01), increased levels of macrophage staining (P = 0.0045), and greater pro-metallo proteinase 2 (P = 0.02). Pharmacologic inhibition of WT male mice with an IL-1α neutralizing antibody resulted in larger AAAs (133.1% vs. 77.0%, P < 0.001). Finally, treatment of IL-1α KO male mice with Anakinra decreased AAA formation compared with vehicle control AAAs (Anakinra + IL-1α KO: 47.7% vs. WT: 147.1%; P = 0.0001). CONCLUSIONS: IL-1α disruption using either genetic or pharmacologic approaches worsens AAAs.

Contemporary prevalence and outcomes of rheumatic mitral valve surgery.

OBJECTIVE: Rheumatic mitral valve disease is often viewed as a historic disease in North America with limited contemporary data. We hypothesized that rheumatic pathology remains common and has worse short-term outcomes and higher resource utilization compared to other mitral valve pathologies. METHOD: All patients undergoing mitral valve repair or replacement (2011-2019) were extracted from a regional Society of Thoracic Surgeons database. Resource utilization metrics included inflation-adjusted hospital costs. Patients were stratified by mitral valve pathology for univariate analysis. RESULT: Out of the 6625 mitral valve procedures, 835 (12.6%) were from rheumatic disease, a proportion that incrementally increased over time (+0.39% per year, p = .032). Among 19 hospitals, there was high variability in number of rheumatic mitral operations (median: 22, interquartile range [IQR]: 5-80) and rate of rheumatic repairs (median: 3%, IQR: 0%-6%). Rheumatic patients were younger (62 vs. 65, p < .0001), more often female (75% vs. 43%, p < .001) and with greater burden of heart failure, multi-valve disease, and lung disease, but less coronary disease. There were no differences in operative mortality (5.2% vs. 5.0%, p = .85) or major morbidity (22.2% vs. 21.8%, p = .83). However, resource utilization was higher for rheumatic patients, including more frequent transfusions (43% vs. 39%, p = .012), longer ICU (73 vs. 64 h, p < .0001) and postoperative length of stay (8 vs. 7 days, p < .0001). CONCLUSIONS: Rheumatic mitral disease accounts for a meaningful (12%) and rising percentage of mitral valve operations in the region, with high variability among hospitals. Rheumatic mitral surgery yielded similar short-term outcomes compared to nonrheumatic pathology, but required greater resource utilization.

Aortic valve biologic protheses: A cohort comparison of premature valve failure.

BACKGROUND: Recent reports suggest an increased rate of early structural valve degeneration (SVD) in the Trifecta bioprosthesis (Abbott Cardiovascular). We sought to compare the intermediate-term outcomes of the Magna (Edwards Life Sciences) and Trifecta valves. METHODS: All surgical aortic valve replacements (SAVRs) with Trifecta or Magna/Magna Ease bioprostheses at an academic medical center were extracted from an institutional database. Patients who survived until after discharge (2011-2019) were included. The primary outcome was valve failure for any reason requiring reintervention or contributing to death, identified by reintervention or review of cause of death. Time to failure was estimated with Kaplan-Meier analysis and Cox Proportional Hazards Modeling. RESULTS: Out of 1444 patients, 521 (36%) underwent Trifecta and 923 (64%) underwent Magna implantation with a median follow-up of 27.6 months. Trifecta patients had larger median valve size (25 vs. 23 mm, p < .001) and lower median gradient (8.0 vs. 10.9 mmHg, p < .001). Trifecta patients had higher 48-month estimated failure rates (20.2 ± 7.6% vs. 2.6 ± 0.7%, p < .0001), with failure rates of 21.4 versus 9.2 failures per 1000 person-years (p < .001). After risk-adjustment, Trifecta patients had a 5.3 times hazard of failure (95% confidence interval: 2.78-12.34, p < .001) compared to Magna patients. Only Trifecta valves failed due to sudden aortic regurgitation, 8 out of 521 (1.5%). CONCLUSION: Despite lower postoperative mean gradients, the Trifecta bioprosthesis may have an increased risk of intermediate-term SVD. Further research is warranted to confirm the potential for sudden valve failure.

Meaningful Patient-centered Outcomes 1 Year Following Cardiac Surgery.

OBJECTIVE: To evaluate meaningful, patient-centered outcomes including alive-at-home status and patient-reported quality of life 1 year after cardiac surgery. BACKGROUND: Long-term patient-reported quality of life after cardiac surgery is not well understood. Current operative risk models and quality metrics focus on short-term outcomes. METHODS: In this combined retrospective/prospective study, cardiac surgery patients at an academic institution (2014-2015) were followed to obtain vital status, living location, and patient-reported outcomes (PROs) at 1 year using the NIH Patient-Reported Outcomes Measurement Information System (PROMIS). We assessed the impact of cardiac surgery, discharge location, and Society of Thoracic Surgeons perioperative predicted risk of morbidity or mortality on 1-year outcomes. RESULTS: A total of 782 patients were enrolled; 84.1% (658/782) were alive-at-home at 1 year. One-year PROMIS scores were global physical health (GPH) = 48.8 ±â€Š10.2, global mental health (GMH) = 51.2 ±â€Š9.6, and physical functioning (PF) = 45.5 ±â€Š10.2 (general population reference = 50 ±â€Š10). All 3 PROMIS domains at 1 year were significantly higher compared with preoperative scores (GPH: 41.7 ±â€Š8.5, GMH: 46.9 ±â€Š7.9, PF: 39.6 ±â€Š9.0; all P < 0.001). Eighty-two percent of patients discharged to a facility were alive-at-home at 1 year. These patients, however, had significantly lower 1-year scores (difference: GPH = -5.1, GMH = -5.1, PF = -7.9; all P < 0.001). Higher Society of Thoracic Surgeons perioperative predicted risk was associated with significantly lower PRO at 1 year (P < 0.001). CONCLUSIONS: Cardiac surgery results in improved PROMIS scores at 1 year, whereas discharge to a facility and increasing perioperative risk correlate with worse long-term PRO. One-year alive-at-home status and 1-year PRO are meaningful, patient-centered metrics that help define long-term quality and the benefit of cardiac surgery.

Mesenchymal Stem Cells Alter MicroRNA Expression and Attenuate Thoracic Aortic Aneurysm Formation.

BACKGROUND: Thoracic aortic aneurysms (TAA) are a progressive disease characterized by inflammation, smooth muscle cell activation and matrix degradation. We hypothesized that mesenchymal stem cells (MSCs) can immunomodulate vascular inflammation and remodeling via altered microRNA (miRNAs) expression profile to attenuate TAA formation. MATERIALS AND METHODS: C57BL/6 mice underwent topical elastase application to form descending TAAs. Mice were also treated with MSCs on days 1 and 5 and aortas were analyzed on day 14 for aortic diameter. Cytokine array was performed in aortic tissue and total RNA was tagged and hybridized for miRNAs microarray analysis. Immunohistochemistry was performed for elastin degradation and leukocyte infiltration. RESULTS: Treatment with MSCs significantly attenuated aortic diameter and TAA formation compared to untreated mice. MSC administration also attenuated T-cell, neutrophil and macrophage infiltration and prevented elastic degradation to mitigate vascular remodeling. MSC treatment also attenuated aortic inflammation by decreasing proinflammatory cytokines (CXCL13, IL-27, CXCL12 and RANTES) and upregulating anti-inflammatory interleukin-10 expression in aortic tissue of elastase-treated mice. TAA formation demonstrated activation of specific miRNAs that are associated with aortic inflammation and vascular remodeling. Our results also demonstrated that MSCs modulate a different set of miRNAs that are associated with decrease leukocyte infiltration and vascular inflammation to attenuate the aortic diameter and TAA formation. CONCLUSIONS: These results indicate that MSCs immunomodulate specific miRNAs that are associated with modulating hallmarks of aortic inflammation and vascular remodeling of aortic aneurysms. Targeted therapies designed using MSCs and miRNAs have the potential to regulate the growth and development of TAAs.

Early Versus Delayed Pacemaker for Heart Block After Valve Surgery: A Cost-Effectiveness Analysis.

BACKGROUND: A significant percentage of patients who acutely develop high-grade atrioventricular block after valve surgery will ultimately recover, yet the ability to predict recovery is limited. The purpose of this analysis was to evaluate the cost-effectiveness of two different management strategies for the timing of permanent pacemaker implantation for new heart block after valve surgery. METHODS: A cost-effectiveness model was developed using costs and probabilities of short- and long-term complications of pacemaker placement, short-term atrioventricular node recovery, intensive care unit stays, and long-term follow-up. We aggregated the total expected cost and utility of each option over a 20-y period. Quality-adjusted survival with a pacemaker was estimated from the literature and institutional patient-reported outcomes. Primary decision analysis was based on an expected recovery rate of 36.7% at 12 d with timing of pacemaker implantation: early placement (5 d) versus watchful waiting for 12 d. RESULTS: A strategy of watchful waiting was more costly ($171,798 ± $45,695 versus $165,436 ± $52,923; P < 0.0001) but had a higher utility (9.05 ± 1.36 versus 8.55 ± 1.33 quality-adjusted life years; P < 0.0001) than an early pacemaker implantation strategy. The incremental cost-effectiveness ratio of watchful waiting was $12,724 per quality-adjusted life year. The results are sensitive to differences in quality-adjusted survival and rates of recovery of atrioventricular node function. CONCLUSIONS: Watchful waiting for pacemaker insertion is a cost-effective management strategy compared with early placement for acute atrioventricular block after valve surgery. Although this is cost-effective from a population perspective, clinical risk scores predicting recovery will aid in personalized decision-making.

Outcomes of surgical mitral valve replacement: A benchmark to assess transcatheter technologies.

BACKGROUND: Clinical trials are underway to evaluate the safety and efficacy of transcatheter mitral valve replacement in intermediate and high surgical risk patients. We analyzed outcomes of surgical mitral valve replacement in a regional consortium to provide benchmark data for emerging alternative therapies. METHODS: All patients undergoing mitral replacement with a Society of Thoracic Surgeons predicted risk of mortality (STS PROM) in a regional consortium from 2001 to 2017 were analyzed. Patients with endocarditis were excluded. Patients were stratified by STS PROM into low (<4%), moderate (4%-8%), and high risk (>8%) cohorts. Mortality, postoperative complications, and resource utilization were evaluated for each group. RESULTS: A total of 1611 patients were analyzed including 927 (58%) low, 370 (23%) moderate, and 314 (20%) high-risk patients. The mean STS PROM was 2%, 5.6%, and 15.4% for each group. Mortality was adequately predicted for all groups while the most common complications included prolonged ventilation, reoperation, and renal failure. Higher risk patients had longer intensive care unit and hospital lengths of stay (2 vs. 3 vs. 5 days, p < .0001 and 7 vs. 8 vs. 10 days, p < .0001) and higher total hospital costs ($38,029 vs. $45,075 vs. $59,171 p < .0001). CONCLUSIONS: Mitral valve replacement is associated with acceptable morbidity and mortality, particularly for low and intermediate-risk patients. These outcomes also serve as a benchmark with which to compare forthcoming results of transcatheter mitral valve replacement trials.

Socioeconomic "Distressed Communities Index" Improves Surgical Risk-adjustment.

OBJECTIVE: We hypothesize the Distressed Communities Index (DCI), a composite socioeconomic ranking by ZIP code, will predict risk-adjusted outcomes after surgery. SUMMARY OF BACKGROUND DATA: Socioeconomic status affects surgical outcomes; however, the American College of Surgeons National Surgery Quality Improvement Program (ACS NSQIP) database does not account for these factors. METHODS: All ACS NSQIP patients (17,228) undergoing surgery (2005 to 2015) at a large academic institution were paired with the DCI, which accounts for unemployment, education level, poverty rate, median income, business growth, and housing vacancies. Developed by the Economic Innovation Group, DCI scores range from 0 (no distress) to 100 (severe distress). Multivariable regressions were used to evaluate ACS NSQIP predicted risk-adjusted effect of DCI on outcomes and inflation-adjusted hospital cost. RESULTS: A total of 4522 (26.2%) patients came from severely distressed communities (top quartile). These patients had higher rates of medical comorbidities, transfer from outside hospital, emergency status, and higher ACS NSQIP predicted risk scores (all P < 0.05). In addition, these patients had greater resource utilization, increased postoperative complications, and higher short- and long-term mortality (all P < 0.05). Risk-adjustment with multivariate regression demonstrated that DCI independently predicts postoperative complications (odds ratio 1.1, P = 0.01) even after accounting for ACS NSQIP predicted risk score. Furthermore, DCI independently predicted inflation-adjusted cost (+$978/quartile, P < 0.0001) after risk adjustment. CONCLUSIONS: The DCI, an established metric for socioeconomic distress, improves ACS NSQIP risk-adjustment to predict outcomes and hospital cost. These findings highlight the impact of socioeconomic status on surgical outcomes and should be integrated into ACS NSQIP risk models.

Gastrointestinal Complications After Cardiac Surgery: Highly Morbid but Improving Over Time.

BACKGROUND: Gastrointestinal complications after cardiac surgery are associated with high morbidity and mortality. We sought to determine the granular impact of individual gastrointestinal complications after cardiac surgery and assess contemporary outcomes. MATERIALS AND METHODS: Patients undergoing cardiac surgery from 2010 to 2017 (6070 patients) were identified from an institutional Society of Thoracic Surgeons database. Records were paired with institutional data assessing gastrointestinal complications and cost. Patients were stratified by early (2010-2013) and current (2014-2017) eras. RESULTS: A total of 280 (4.6%) patients experienced gastrointestinal complications including Clostridiumdifficile infection (94, 33.6%), gastrointestinal bleed (86, 30.7%), hepatic failure (66, 23.6%), prolonged ileus (59, 21.1%), mesenteric ischemia (47, 16.8%), acute cholecystitis (17, 6.0%), and pancreatitis (14, 5.0%). Gastrointestinal complications were associated with higher rates of early postoperative major morbidity [206 (73.6%) versus 773 (13.4%), P < 0.0001], mortality [78 (27.9%) versus 161 (2.8%), P < 0.0001], length of stay (23 versus 6 d, P < 0.0001), and discharge to a facility [115 (41.1%) versus 1395 (24.1%), P < 0.0001]. Patients suffering gastrointestinal complications had worse risk-adjusted long-term survival (hazard ratio: 3.0, P < 0.0001) and higher adjusted cost ($9,173, P = 0.05). Between eras, there was no difference in incidence of gastrointestinal complications [139 (4.4%) versus 141 (4.8%), P = 0.51] or rate of specific complications (all P > 0.05). However, long-term survival increased in modern era (P < 0.0001). CONCLUSIONS: Although incidence of gastrointestinal complications after cardiac surgery has not changed over time, long-term survival has improved. Gastrointestinal complications remain associated with high resource utilization and major morbidity, but patients are now more likely to recover, highlighting the benefit of quality improvement efforts.

Concomitant Left Atrial Appendage Closure Outcomes and Cost: A Multi-institutional Cohort Analysis.

BACKGROUND: Left atrial appendage closure (LAAC) is frequently performed during cardiac operations, but the impact of LAAC on patient outcomes is not fully known. We hypothesized that the addition of LAAC would increase morbidity and resource utilization. METHODS: All patients undergoing cardiac surgery from a multi-institutional Society of Thoracic Surgeons database from 2011 to 2016 were stratified by LAAC. The effect of LAAC on risk-adjusted outcomes was assessed by hierarchical regression modeling accounting for preoperative risk factors, planned surgical procedure, hospital, and year. RESULTS: Concomitant LAAC was performed on 2384 of 28,311 patients (9.3%), who were older, with a greater burden of preoperative atrial fibrillation and heart failure. Although the addition of LAAC increased the risk of new-onset postoperative atrial fibrillation (OR 1.69, P < 0.01), it did not increase rates of major morbidity (OR 1.00, P = 0.970), stroke (OR 0.92, P = 0.787), or mortality (OR 0.93, P = 0.684). Although cardiopulmonary bypass time was not significantly increased by LAAC, patients' total hospitalization costs were $3035 higher (P = 0.018). CONCLUSIONS: Although concomitant LAAC was not associated with major complications, there were higher risk-adjusted rates of new-onset postoperative atrial fibrillation. Furthermore, LAAC added approximately $3000 to a patient's total hospital cost. These short-term risks and costs should be weighed against potential long-term benefits of left atrial appendage closure.

Female Mice Exhibit Abdominal Aortic Aneurysm Protection in an Established Rupture Model.

BACKGROUND: Male gender is a well-established risk factor for abdominal aortic aneurysm (AAA), whereas estrogen is hypothesized to play a protective role. Although rupture rates are higher in women, these reasons remain unknown. In the present study, we sought to determine if female mice are protected from AAA rupture. MATERIALS AND METHODS: Apolipoprotein E-deficient male and female mice (aged 7 wk; n = 25 per group) were infused with angiotensin II (AngII; 2000 ng/kg/min) plus ß-aminopropionitrile (BAPN) in the drinking water for 28 d to test the effects of gender on AAA rupture. Separately, a second group of male apolipoprotein E-deficient mice underwent AngII infusion + BAPN while being fed high-fat phytoestrogen free or a high-fat phytoestrogen diet to assess effects of phytoestrogens on rupture. In a third group, female mice either underwent oophorectomy or sham operation 4 wk before infusion of AngII and BAPN to further test the effects of female hormones on AA rupture. Surviving mice abdominal aorta were collected for histology, cytokine array, and gelatin zymography on postoperative day 28. RESULTS: Female mice had decreased AAA rupture rates (16% versus 46%; P = 0.029). Female mice expressed fewer elastin breaks (P = 0.0079) and decreased smooth muscle cell degradation (P = 0.0057). Multiple cytokines were also decreased in the female group. Gelatin zymography demonstrated significantly decreased pro-matrix metalloproteinase 2 in female mice (P = 0.001). Male mice fed a high dose phytoestrogen diet failed to decrease AAA rupture. Female mice undergoing oophorectomy did not have accelerated aortic rupture. CONCLUSIONS: These data are the first to attempt to tease out hormonal effects on AAA rupture and the possible role of gender in rupture.

Bariatric surgery reduces long-term rates of cardiac events and need for coronary revascularization: a propensity-matched analysis.

BACKGROUND: Obesity and obesity-related comorbidities are associated with increased risk of coronary artery disease (CAD). Bariatric surgery results in durable weight loss and improvement in numerous CAD risk factors, yet limited data exist on CAD-related outcomes. We hypothesized that bariatric surgery would lead to decreased risk of CAD and reduced rates of coronary revascularization procedures. METHODS: All patients who underwent bariatric surgery at a single medical center from 1985 to 2015 were identified. A control population of morbidly obese patients who did not undergo bariatric surgery was identified using an institutional clinical data repository over the same study period, propensity score matched 1:1 on patient demographics and comorbidities including cardiac history. Univariate analyses were performed to compare outcomes in the surgery and non-surgery groups. RESULTS: A total of 3410 bariatric surgery patients and 45,750 non-surgical patients were identified. After 1:1 propensity-score matching, a total of 3242 patients in each group were found to be well balanced in baseline characteristics and risk factors. With a median follow-up of greater than 6 years, the surgery group had significantly lower rates of myocardial infarction (1.8% vs. 10.0%; RR 0.18), coronary catheterization (1.9% vs. 8.8%; RR 0.22), percutaneous coronary intervention (0.4% vs. 7.8%; RR 0.05), and coronary artery bypass grafting (0.6% vs. 2.3%; RR 0.26). Similar benefits were observed for subgroups of patients with and without diabetes. CONCLUSIONS: Bariatric surgery was associated with a significant reduction in the incidence of myocardial infarction as well as lower rates of coronary revascularization in a propensity-matched cohort of morbidly obese patients. Though the retrospective nature of this study may have introduced a degree of selection bias, these outcomes support increased utilization of bariatric surgery for the prevention of heart disease.

Socioeconomically Distressed Communities Index independently predicts major adverse limb events after infrainguinal bypass in a national cohort.

BACKGROUND: Socioeconomic status is a major determinant of not only quality of life, but also mortality and health care-related outcomes. We hypothesized that patients coming from distressed communities would have worse short- and long-term limb related outcomes after infrainguinal bypass. METHODS: The infrainguinal bypass national Vascular Quality Initiative datasets for 2003 to 2018 were used. Clinical data were paired with the Distressed Communities Index (DCI) score before extraction. The DCI accounts for unemployment, education level, poverty rate, median income, business growth, and housing vacancies at the zip code level, with a range of 0 (no distress) to 100 (severe distress). Severely distressed communities were defined as DCI greater than 75 for univariate analysis. Hierarchical multivariable modeling adjusted for baseline and operative risk factors, and clustering at the hospital level. RESULTS: The 9711 patients who underwent infrainguinal bypass from severely distressed communities (out of 40,109 total) were younger, more likely to smoke, disproportionately African American, with more comorbid disease (all P < .05). Patients from less distressed communities had lower rates of critical limb ischemia (56% DCI ≤ 75 vs 60% DCI > 75; P < .0001) and prior amputation (4.7 vs 6.3%; P < .0001). There was no difference in in-hospital mortality (1.3% vs 1.3%; P = .906) or major adverse cardiovascular events (4.1% vs 3.7%; P = .097). However, patients from distressed communities had higher rates of major adverse limb events (MALE; 11.7% vs 14.4%; P < .0001), and the components amputation, thrombectomy, and revision. After risk adjustment, DCI remained an independent predictor of in-hospital MALE (odds ratio, 1.05 per 25 DCI points; 95% confidence interval [CI], 1.02-1.08; P = .001) and long-term MALE (hazard ration [HR] 1.02; 95% CI, 1.00-1.04; P = .045). DCI is predictive of long-term graft occlusion (HR, 1.04; 95% CI, 1.00-1.07; P = .028) and amputation (HR, 1.09; 95% CI, 1.06-1.12; P < .0001). CONCLUSIONS: The DCI is an independent predictor of MALE after infrainguinal bypass. Patients from distressed communities are at an increased risk of long-term graft occlusion, which is disproportionately treated with amputation instead of surgical limb-saving alternatives. Socioeconomic factors impact vascular disease and surgical outcomes with disparities that warrant further investigation.

Preoperative beta blockade is associated with increased rates of 30-day major adverse cardiac events in critical limb ischemia patients undergoing infrainguinal revascularization.

OBJECTIVE: The association between beta blockers and cardiovascular or limb-related outcomes after revascularization for critical limb ischemia (CLI) remains unclear. The objective of this study was to assess the impact of preoperative beta blockade on 30-day major adverse cardiac events (MACEs) and major adverse limb events (MALEs) in patients undergoing infrainguinal revascularization for CLI. We hypothesized that rates of MALEs and MACEs will be higher in patients not receiving preoperative beta blockade. METHODS: The National Surgical Quality Improvement Program vascular targeted file for 2011 to 2014 identified patients receiving beta blockade and undergoing infrainguinal endovascular intervention and open bypass for CLI. Primary outcomes including 30-day MACE (stroke, myocardial infarction [MI], or death) and MALE (untreated loss of patency, reintervention, or amputation) were compared between patients taking and not taking preoperative beta blockers. Multivariate logistic regression identified independent predictors of MACEs and MALEs. RESULTS: A total of 11,785 revascularizations were performed for CLI during the study period (7408 bypasses vs 4377 endovascular interventions). Preoperative beta blockers were used by 7365 patients, including 4541 (61.7%) in the open bypass cohort and 2824 (64.5%) in the endovascular group (P < .01). MACEs and MI were significantly higher in patients with preoperative beta blockers (MACEs, 5.8% vs 3.4% [P < .0001]; MI, 3.1% vs 1.8% [P < .0001]). After controlling for cardiac risk factors, beta blockers independently predicted MACEs (odds ratio [OR], 1.27; P = .03) and MI (OR, 1.36; P = .03) but not stroke (OR, 1.17; P = .58) or 30-day mortality (OR, 1.22; P = .19). Beta-blocker use did not have an effect on MALEs (OR, 0.99; P = .88). CONCLUSIONS: In patients with CLI, preoperative beta blockade was an independent predictor of 30-day MI and MACEs after controlling for other cardiovascular risk factors. Beta blockers did not have an impact on short-term limb-related outcomes. The association between beta blockade and revascularization for CLI deserves further investigation.

Increased warm ischemia time during vessel harvest decreases the primary patency of cryopreserved conduits in patients undergoing lower extremity bypass.

OBJECTIVE: Autologous vein is the preferred conduit for lower extremity bypass. However, it is often unavailable because of prior harvest or inadequate for bypass owing to insufficient caliber. Cryopreserved cadaveric vessels can be used as conduits for lower extremity revascularization when autogenous vein is not available and the use of prosthetic grafts is not appropriate. Many studies have shown that donor characteristics influence clinical outcomes in solid organ transplantation, but little is known regarding their impact in vascular surgery. The purpose of this study was to examine the effects donor variables have on patients undergoing lower extremity bypass with cryopreserved vessels. METHODS: The tissue processing organization was queried for donor blood type, warm ischemia times (WITs), and serial numbers of cryopreserved vessels implanted at a single center from 2010 to 2016. The serial numbers were then matched with their respective patients using the institutional Clinical Data Repository and patient data were obtained from the Clinical Data Repository and chart review. Primary outcomes were primary patency of the bypass conduits and limb salvage. Time to loss of patency was evaluated using Kaplan-Meier methods and a Cox proportional hazards model determined risk-adjusted predictors of patency and limb salvage. RESULTS: Sixty patients underwent lower extremity bypass with 65 cryopreserved vessels (23 superficial femoral arteries, 41 saphenous veins, 1 femoral vein). Thirty-eight procedures were reoperations. There were 21 inflow, 44 outflow, and 44 infrainguinal procedures. Preexisting comorbidities did not differ significantly between those who lost patency and those who did not. The mean WIT among the entire cohort was 892.3 ± 389.1 minutes (range, 158.0-1434.0 minutes). The median follow-up was 394 days. Kaplan-Meier analysis demonstrated an overall 1-year primary patency rate of 51%. Primary patency at 1 year was 67% and 41% for inflow and outflow procedures, respectively, and did not differ significantly between the two groups (P = .15). Donor-to-recipient ABO incompatibility was not associated with loss of primary patency. The 1-year amputation-free survival was 74%. Primary patency significantly decreased with each hourly increase in WIT on risk-adjusted analysis (hazard ratio, 1.1; P = .02). CONCLUSIONS: Higher cryopreserved vessel WIT was associated with increased risk-adjusted loss of primary patency in this cohort. At 1 year, the overall primary patency was 51% and amputation-free survival was 74%. Vascular surgeons should be aware that WIT may affect outcomes for lower extremity bypass.

Socioeconomic Distressed Communities Index associated with worse limb-related outcomes after infrainguinal bypass.

OBJECTIVE: Several studies have demonstrated that socioeconomic factors may affect surgical outcomes. Analyses in vascular surgery have been limited by the availability of individual or community-level socioeconomic data. We sought to determine whether the Distressed Communities Index (DCI), a composite socioeconomic ranking by ZIP code, could predict short- and long-term outcomes for patients with peripheral artery disease. METHODS: All Virginia Quality Initiative patients (n = 2578) undergoing infrainguinal bypass (2011-2017) within a region of 17 centers were assigned a composite DCI score. The score was developed by the Economic Innovation Group and is normally distributed from 0 (no distress) to 100 (severe distress) based on measures of community unemployment, education level, poverty rate, median income, business growth, and housing vacancies. Severely distressed communities were defined as the top quartile DCI (>75). Hierarchical regression assessed short-term outcomes, and time-to-event analyses assessed long-term results. RESULTS: Infrainguinal bypass patients in this study came from disproportionately distressed communities, with 29% of patients living within the highest distress DCI quartile (P < .0001), with high variability by hospital (DCI range, 12-67). These patients from severely distressed areas were younger, more likely to smoke, and disproportionately African American and had higher rates of medical comorbidities (all P < .05). Whereas patients from severely distressed communities had an equivalent rate of 30-day major adverse cardiac and cerebrovascular events (5% vs 4%; P = .86), they had increased rates of major adverse limb events (MALEs) at 13% vs 10% (P = .03). This trend persisted in the long term, with higher 1-year estimates of MALEs (21% vs 17%; P = .01) as well as the components of amputation (17% vs 12%; P = .006) and thrombectomy (11% vs 6%; P = .002). Patients with high socioeconomic distress also had higher rates of occlusion (17% vs 11%; P = .003). CONCLUSIONS: In this study, patients from severely distressed communities were found to have increased rates of MALEs, an association that persisted long term. Mitigating risk associated with socioeconomic determinants of health has the potential to improve outcomes for patients with peripheral artery disease.