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We propose a novel algorithm for the navigation of agents based on reinforcement learning, using boredomas an element of intrinsic motivation. Improvements obtained with the inclusion of this element over classicstrategies are shown through simulations. Boredom is modeled through a chaotic element that generates conditionsfor the creation of routes when the environment does not offer any reward, allowing prompting the robotto navigate. Our proposal seeks to avoid what classical algorithms suffer in scenarios without rewards, generatinglosses of time in the resolution. We demonstrate experimentally that by adding the element of boredomit is possible to generate routes in scenarios in which rewards do not exist, allowing the use of these strategiesin real circumstances and facilitating the robot's navigation towards its objective. The most important contributionsustained by this work corresponds to the fact that it is possible to improve navigation in completelyadverse scenarios for a navigation algorithm based on rewards.

Background Additive risks of combining supra-aortic trunk surgical reconstruction (SAT) with carotid endarterectomy (CEA) for associated carotid bifurcation and great vessel disease management are not well defined. This study sought to define risk of combining SAT with CEA. Study design Isolated CEA (ICEA) and CEA+SAT (from 2005 to 2015) were identified from NSQIP, excluding nonocclusive indications. CEA+SAT were compared with ICEA as well as a propensity-matched ICEA cohort. Primary outcomes included 30-day stroke, death, and composite (SD). Outcomes were then weighted by symptomatic status. Univariate and logistic regression analyses were performed. Results Patients included 79,477 ICEA and 270 CEA+SAT. SAT reconstructions included 19 (7%) aorto-carotid bypasses, 21 (8%) carotid-subclavian transpositions, 85 (31%) carotid-carotid bypasses, and 145 (54%) carotid-subclavian bypasses. There was no difference in 30-day mortality (vs CEA+SAT 1.5% vs ICEA 0.7% p = 0.12). CEA+SAT had higher rates of stroke (3.7% vs 1.6%, p = 0.005) and stroke and death (SD) (4.8% vs 2.1%, p = 0.001). Predictors of SD included CEA+SAT (odds ratio [OR] 5.2, 95% CI 1.03–26.3, p = 0.046) and symptomatic status (OR 1.9, 95% CI 1.1–3.2, p = 0.02). After propensity matching, CEA+SAT continued to have higher rates of stroke (3.4% vs 0.4%, p = 0.01) and SD (4.5% vs 1.5%, p = 0.04), with similar mortality (1.5% vs 1.1%, p = 0.70). No differences were noted in primary endpoints in asymptomatic patients. In symptomatic patients, CEA+SAT carried significantly higher stroke (5.6% vs 2.1%, p = 0.04) and SD risk (7.0% vs 2.8%, p = 0.03). Conclusions CEA+SAT confers increased risk of stroke and SD over ICEA. Symptomatic status and concomitant procedure contribute to this risk. Management should be considered within the context of lesion characteristics, patient longevity, and individual operative risk profile.

Current reporting on cardiac surgical outcomes focuses on a patient's status at 30 days and lacks long-term meaningful data. The purpose of this study was to determine the impact of complications after cardiac operation on patient-reported outcomes (PROs) at 1 year after surgery.All patients undergoing cardiac operation at an academic institution (2014-2015) were contacted 1 year after surgery to obtain vital status, location, and PROs using the validated National Institutes of Health Patient-Reported Outcomes Measurement Information System (NIH-PROMIS). Records were merged with Society of Thoracic Surgeons (STS) data, and multivariate linear regression evaluated the risk-adjusted effects of complications on 1-year PROs.A total of 782 eligible patients underwent cardiac operation, with PROs data available for 91% of patients alive at 1 year (648 of 716). Mean NIH-PROMIS scores were global physical health (GPH), 48.8 ± 10.2; global mental health (GMH), 51.3 ± 9.5; and physical functioning (PF), 45.5 ± 10.2 (reference score for general adult population, 50 ± 10). Occurrence of an STS Major Morbidity (prolonged ventilation, renal failure, reoperation, stroke, or deep sternal wound infection) significantly reduced 1-year PROs (GPH, 45.4 ± 8.9 [P.001]; GMH, 48.6 ± 9.5 [P = .01]; PF, 40.9 ± 10.2 [P.001]). After risk adjustment, incidence of a STS Major Morbidity, prolonged ventilation, or renal failure had a significant adverse effect on 1 or more PRO domains.Although cardiac surgical patients have PROs scores similar to the general population, complications after cardiac operation continue to negatively influence patient quality of life 1 year after surgery. Use of NIH-PROMIS shows that prolonged ventilation and renal failure have the largest impact on 1-year patient-reported outcomes.

A quality improvement project was delivered by a federally qualified health center to improve patient access to psychiatric services. The effort was supported by training and technical assistance provided by the American Psychiatric Association Support and Alignment Network. Over a 3-year period, the collaborative care model (CoCM) and other integrated consultative strategies were implemented. As a result, the waitlist was reduced from 350 patients to 1 patient. The use of the CoCM and other integrated care strategies was successful in eliminating a psychiatric service waitlist in this primary care setting.

Annular enlargement (AE) is a critical technique to avoid patient-prosthesis mismatch and may help facilitate future valve-in-valve (ViV) transcatheter replacement. We hypothesized that the addition of annular enlargement would increase risk of morbidity and mortality and that the number of annular enlargement procedures is increasing to accommodate future ViV procedures.Patients undergoing aortic valve replacement ± coronary surgery (2012 to 2017) were extracted from a regional Society of Thoracic Surgeons database. Patients were stratified by annular enlargement and era, pre-ViV (2012 to 2014) vs ViV (2015 to 2017) for univariate analysis. Risk-adjusted outcomes were assessed by hierarchical regression modeling adjusting for predicted risk of mortality.Of 6045 patients, the 300 (5.0%) who received an annular enlargement were younger and more commonly female. Patients receiving an annular enlargement had higher complication rates including operative mortality (4.7% vs 2.5%, P = .024). After risk adjustment, AE was independently associated with increased mortality (odds ratio, 2.06, P = .016) and major morbidity (odds ratio, 1.41, P = .042). The rate of enlargement increased from 3.9% pre-ViV to 6.3% ViV (P .001). The use of ViV capable valves (bioprosthetic ≥23 mm) from 61% to 67% (P = .001), and more in AE patients (30% vs 11% non-AE). Alternatively, the rate of patient prosthesis mismatch declined from 23% to 16%.Increasing utilization of AE coincides with a decline in patient prosthesis mismatch and may facilitate future ViV transcatheter aortic valve replacement. However, AE was independently associated with increased morbidity and mortality. High variability in AE volume may be increasing risk and deserves further investigation.

Background: Ischemic and hemorrhagic cerebrovascular accidents remain common among patients with centrifugal-flow left ventricular assist devices, despite improvements in survival and device longevity. We compared the incidence of neurologic adverse events (NAEs) associated with 2 contemporary centrifugal-flow left ventricular assist devices: the Abbott HeartMate3 (HM3) and the Medtronic HeartWare HVAD (HVAD). Methods: Using the Society of Thoracic Surgeons Interagency Registry for Mechanically Assisted Circulatory Support (Intermacs), we collected data on adult patients who received a centrifugal-flow left ventricular assist device as a primary isolated implant between January 1, 2017, and September 30, 2019. Major NAEs were defined as transient ischemic attack, ischemic cerebrovascular accident, or hemorrhagic cerebrovascular accident. The association of HVAD with risk of NAE in the first year after implant was evaluated using propensity score matching to balance for preimplant risk factors. After matching, freedom from first major NAE in the HM3 and HVAD cohorts was compared with Kaplan-Meier curves. A secondary analysis using multivariable multiphase hazard models was used to identify predictors of NAE, which uses a data-driven parametric fit of the early declining and constant phase hazards and the associations of risk factor with either phase. Results: Of 6205 included patients, 3129 (50.4%) received the HM3 and 3076 (49.6%) received the HVAD. Median follow-up was 9 and 12 months (HM3 and HVAD, respectively). Patients receiving HVAD had more major NAEs (16.4% versus 6.4%, P P P P P Conclusions: HM3 is associated with lower hazard of major NAEs than is HVAD beyond the early postimplantation period and during the constant hazard phase. Defining the explanation for this observation will inform device selection for individual patients.

Limited prior studies suggest patients with acute type A aortic dissection (ATAAD) and prior cardiac surgery are at increased risk for major complications compared with those without a prior sternotomy. We sought to investigate the impact of prior cardiac surgery on ATAAD outcomes across a multicenter regional consortium.Patients undergoing surgical intervention for ATAAD in a regional Society of Thoracic Surgeons database between 2002 and 2017 were stratified by prior cardiac surgery (reoperative) status. Demographics, operative characteristics, outcomes and cost data were compared by univariate analysis. Multivariable regression models assessed risk-adjusted impact of reoperative status on outcomes.A total of 1,332 patients underwent surgery for ATAAD, of whom 138 (10.4%) were reoperations. Reoperative patients were older (63 vs. 58 years, p0.01) with more comorbidities. These patients had longer median cardiopulmonary bypass times (218 vs 177 minutes, p0.01) and increased blood product utilization; however rates of aortic arch, root, and valve procedures were similar. On unadjusted analysis operative mortality was higher in reoperative patients (28% vs 15%, p0.01) with a longer total length of stay (13 vs 10 days, p = 0.02). Reoperative patients exhibited a trend toward decreased mortality at high-volume centers (25.7% vs 37.9%, p = 0.19). After risk adjustment reoperative status remained associated with mortality (odds ratio, 2.1; p0.01) as well as composite morbidity-mortality (odds ratio, 2.2; p0.01).In this multicenter cohort undergoing repair of ATAAD prior cardiac surgery was associated with an increased morbidity and mortality. Centralization to high-volume centers and emerging technologies may improve outcomes in this high-risk population.

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. 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. 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. 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.

BACKGROUND: Sternal wound infections (SWI) can be a devastating long-term complication with significant morbidity and health care cost. The purpose of this analysis was to evaluate the cost-effectiveness of negative pressure incision management systems (NPIMS) in cardiac surgery. MATERIALS AND METHODS: All cardiac surgery cases at an academic hospital with risk scores available (2009–2017) were extracted from an institutional database (n=4,455). Patients were stratified by utilization of NPIMS and high-risk was defined as above the median. Costs included infection related readmissions and were adjusted for inflation. Multivariable regression models assessed the risk-adjusted cost of SWI and efficacy of NPIMS use. Cost-effectiveness was modeled using TreeAge Pro using institutional results. RESULTS: The rate of deep SWI was 0.9% with an estimated cost of $111,175 (p

Purpose To characterize the degree of venous collateralization before and after endovascular therapy and determine the effect of collateralization on success of thrombolysis and rate of repeat intervention in patients with Paget–Schroetter syndrome. Materials and Methods A single-center retrospective study of 37 extremities in 36 patients (mean age, 32.64 y; range, 15–72 y; 24 men) with PSS treated with endovascular therapy from 2007 through 2017 was conducted. Venograms at presentation, after lysis, postoperatively, and at each repeat intervention were graded for venous stenosis, thrombus burden, and collateralization on a 5-point scale. Collateralization was classified as high-grade (9 extremities) or low-grade (28 extremities) based on grading of the venograms at presentation. Results Primary technical success rate for endovascular treatment was 100%. Eighty-six percent of patients (32 of 37) underwent thrombolysis, 91% (34 of 37) underwent mechanical thrombectomy, and 83% (30 of 37) underwent balloon angioplasty. Overall primary patency rate was 50% at 12 months. The repeat intervention rate within 12 months was significantly higher for extremities with high- vs low-grade collateralization (89% vs 43%; P = .016). There was a significant decrease in the median grade of collateral severity after initial intervention (2 vs 1; P = .044) and 1 day postoperatively (2 vs 1; P = .040) vs the venogram at presentation. Conclusions Severity of venous collateralization on the venogram at presentation of patients with PSS does not appear to affect success of endovascular therapy but may predict long-term patency of affected extremities. Patients in this cohort with severe collateralization on presentation were more likely to need repeat intervention.

Pulmonary hypertension portends worse outcomes in cardiac valve surgery; however, isolated pulmonary artery pressures may not reflect patients' global cardiac function accurately. To better account for the interventricular relationship, the authors hypothesized that patients with greater pulmonary-systemic ratios (mean pulmonary arterial pressure)/(mean systemic arterial pressure) would correlate with worse outcomes after valve surgery.Retrospective cohort study.Single academic hospital.The study comprised 314 patients undergoing valve surgery with or without coronary artery bypass grafting (2004-2016) with Society of Thoracic Surgeons predicted risk scores and preoperative right heart catheterization.None.The pulmonary-systemic ratio was calculated as follows: mean pulmonary arterial pressure/mean systemic arterial pressure. Patients were stratified by pulmonary-systemic ratio quartile. Logistic regression was used to assess the risk-adjusted association between pulmonary-systemic ratio or mean pulmonary arterial pressure. Median pulmonary-systemic ratio was 0.33 (Q1-Q3: 0.23-0.65); median pulmonary arterial pressure was 29 (21-30) mmHg. Patients with the highest pulmonary-systemic ratio had the highest rates of morbidity and mortality (p0.0001). A high pulmonary-systemic ratio was associated with longer duration in the intensive care unit (p0.0001) and hospital (p0.0001). After risk-adjustment, pulmonary-systemic ratio and pulmonary arterial pressure were independently associated with morbidity and mortality, but the pulmonary-systemic ratio (odds ratio 23.88, p = 0.008, Wald 7.1) was more strongly associated than the pulmonary arterial pressure (odds ratio 1.035, p = 0.011, Wald 6.5).The pulmonary-systemic ratio is more strongly associated with risk-adjusted morbidity and mortality in valve surgery than pulmonary arterial pressure. By integrating ventricular interactions, this metric may better characterize the risk of valve surgery.

Under the new heart allocation policy patients needing durable left ventricular assist devices receive lower priority on the transplant list. We sought to identify predictors of successful heart transplant after durable device implant as a means to inform patient care in the current era.All patients (N = 25,164) undergoing primary durable left ventricular device implant in The Society of Thoracic Surgeons Intermacs database (2010-2019) were evaluated. Patients identified as bridge to transplant (BTT; n = 5242) or bridge to candidacy (n = 6248) were analyzed with the endpoint of transplant before (n = 10,588) and after (n = 902) the change in the heart allocation system on October 18, 2018. Multivariable hazard modeling was used to assess risk-adjusted time to event associations.Of 11,490 patients, 45.5% progressed to transplant (BTT, 53.0%; bridge to candidacy, 36.6%), most by 14 months after left ventricular assist device implant. Under the new allocation system progression to transplant was significantly lower at 14 months (18.6% vs 34.8%, P.001). Factors associated with successful BTT before the allocation change included BTT status, white race, and married. Under the new allocation system BTT status (hazard ratio, 1.79; 95% confidence interval, 1.19-2.69; P.0054) remained a positive predictor, whereas blood type O (hazard ratio, 0.43; 95% confidence interval, 0.28-0.65; P.0001) remained a negative predictor.Despite having priority in the previous allocation system, less than half of BTT and bridge to candidacy patients progressed to transplant. Under the current system these numbers are further reduced. Heart teams should consider the implications of longer wait times for a durable left ventricular assist device when determining the optimal bridging strategy.

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.

In this article, we propose a new scheme for a fuzzy logic controller, which includes acceleration as one of its linguistic variables, as opposed to other techniques and approaches that have been developed and reported in the literature. This method is used for controlling the tracking of the trajectory followed by the joints of a 2-DoF manipulator robot. To this end, a complete simulation environment is developed through the MatLab/Simulink&reg, software. The dynamic model of the manipulator robot includes a vector that consists of the estimate of the friction forces present in the joints. Then, a controller based on fuzzy logic is designed and implemented for each joint. Finally, the performance of the developed system is assessed and then compared to the performance of a classic PID controller. The incorporation of the fuzzy variable acceleration significantly improved the system&rsquo, s response.

This article presents the implementation of a learning environment for the teaching of control systems. This environment integrates physical equipment and simulation, monitoring, and control through a network. A software platform based on ROS (Robotic Operating System) grants access to the system through intranet and Internet, facilitating the integration of new test equipment. The environment developed can be used in didactic experiences both inside and outside the classroom, enhancing the learning of four main study topics: modeling, analysis, parameter estimation, and controller design.

Permanent pacemaker (PPM) implantation has been touted as an inconsequential complication after transcatheter aortic valve replacement. As transcatheter aortic valve replacement moves to lower risk patients, the long-term implications remain poorly understood; therefore, we evaluated the long-term outcomes of pacemaker for surgical aortic valve replacement patients.A total of 2,600 consecutive patients undergoing surgical aortic valve replacement over the past 15 years were reviewed using The Society of Thoracic Surgeons (STS) institutional database and Social Security death records. Patients were stratified by placement of a PPM within 30 days of surgery. The impact of PPM placement on long-term survival was assessed by Kaplan-Meier analysis and risk-adjusted survival by Cox proportional hazards modeling.A total of 72 patients (2.7%) required PPM placement postoperatively. Patients requiring PPM had more postoperative complications, including atrial fibrillation (43.1% versus 27.0%, p = 0.003), prolonged ventilation (16.7% versus 5.7%, p0.0001), and renal failure (12.5% versus 4.6%, p = 0.002). These led to greater resource utilization including longer intensive care unit stay (89 versus 44 hours, p0.0001) and hospital length of stay (9 versus 6 days, p0.0001), and higher inflation-adjusted hospital cost ($81,000 versus $47,000, p0.0001). Median follow-up was 7.5 years, and patients requiring PPM had significantly worse long-term survival (p = 0.02), even after risk adjustment with STS predicted risk of mortality (hazard ratio 1.48, p = 0.02).The need for PPM after aortic valve replacement independently reduces long-term survival. The rate of PPM placement after surgical aortic valve replacement remains very low but dramatically increases resource utilization. As transcatheter aortic valve replacement expands to low-risk patients, the impact of PPM placement on long-term survival warrants close monitoring.

Background Frailty is an important predictor of outcomes after cardiac surgery, but utility is limited by difficult assessment and quantification. We hypothesize that sarcopenia defined as psoas muscle cross-sectional area is a useful predictor of surgical aortic valve replacement outcomes in moderate to high-risk patients. Methods Moderate to high risk patients (predicted risk of mortality greater than 3%) who underwent surgical aortic valve replacement with or without coronary artery bypass were extracted from an institutional database (2009 to 2016). Psoas index was calculated as the cross-sectional area of the psoas muscle at the L4 vertebral level normalized to body surface area. Patients were stratified by sarcopenia status, defined as less than 25th sex-specific percentile. Multivariable regression analysis identified risk-adjusted associations with psoas index using The Society of Thoracic Surgeons predicted risk scores. Results Of the 240 patients included, the median predicted risk of mortality was 6%, median age 80 years, and 40% were female. Patients with (33.3%) and without (66.7%) sarcopenia had equivalent baseline risk (median predicted risk of mortality 5.7% versus 6.0%, p = 0.29). Patients with sarcopenia had higher 1-year mortality (31.9% versus 16.9% p = 0.03). Psoas index significantly predicted risk-adjusted 1-year mortality (odds ratio 0.84, p = 0.02) and long-term mortality (hazard ratio 0.92, p = 0.04), as well as risk-adjusted major morbidity, prolonged ventilation, length of stay, discharge to a facility, and hospital cost. Finally, psoas index measurements were highly reproducible (Pearson correlation coefficient 0.944). Conclusions Psoas index is an easily obtained and reproducible measure of frailty that predicts risk-adjusted resource utilization, morbidity, and long-term mortality. Psoas index may improve procedural selection and risk adjustment in high-risk patients with aortic valve disease.

Although tricuspid valve operations remain associated with high mortality (approximately 8% to 10%), no robust prediction models exist to support clinical decision making. We developed a preoperative clinical risk model with an easily calculable clinical risk score (CRS) to predict mortality and major morbidity after isolated tricuspid valve surgery.The Society of Thoracic Surgeons database records were evaluated for 2,050 isolated TV repair and replacement operations for any etiology performed at 50 hospitals (2002 to 2014) in a number of states. Parsimonious preoperative risk prediction models were developed using multiple-level mixed effects regression to estimate mortality and composite major morbidity risk. Model results were utilized to establish a novel CRS for patients undergoing tricuspid valve operations. Models were evaluated for discrimination and calibration.Operative mortality and composite major morbidity rates were 9% and 42%, respectively. Final regression models performed well (both p0.001; areas under the receiver-operating characteristics curve 0.74 and 0.76) and included preoperative factors: age, sex, stroke, hemodialysis, ejection fraction, lung disease, New York Heart Association class, reoperation, and urgent or emergency status (all p0.05). A simple CRS from 0 to 10+ was highly associated (p0.001) with incremental increases in predicted mortality and major morbidity. Predicted mortality risk ranged from 2% to 34% across CRS categories, and predicted major morbidity risk ranged from 13% to 71%.Mortality and major morbidity after isolated tricuspid valve surgery can be predicted using preoperative patient data from The Society of Thoracic Surgeons National Adult Cardiac Database. A simple clinical risk score predicts mortality and major morbidity after isolated tricuspid valve surgery. This score may facilitate perioperative counseling and identification of suitable patients for tricuspid valve surgery.

Objectives Obtaining National Institutes of Health funding for heart transplant research is becoming increasingly difficult, especially for surgeons. We sought to determine the impact of National Institutes of Health–funded cardiac transplantation research over the past 30 years. Methods National Institutes of Health Research Portfolio Online Reporting Tools Expenditures and Results was queried for R01s using 10 heart transplant–related terms. Principal Investigator, total grant funding amount, number of publications, and citations of manuscripts were collected. A citation-based Grant Impact Metric was assigned to each grant: sum of citations for each manuscript normalized by the funding of the respective grant (per $100K). The department and background degree(s) (MD, PhD, MD/PhD) for each funded Principal Investigator were identified from institutional faculty profiles. Results A total of 321 cardiac transplantation R01s totaling $723 million and resulting in 6513 publications were analyzed. Surgery departments received more grants and more funding dollars to study cardiac transplantation than any other department (n = 115, $249 million; Medicine: n = 93, $208 million; Pathology: 26, $55 million). Surgeons performed equally well compared with all other Principal Investigators with respect to Grant Impact Metric (15.1 vs 20.6; P = .19) and publications per $1 million (7.5 vs 6.8; P = .75). Finally, all physician-scientists (MDs) have a significantly higher Grant Impact Metric compared with nonclinician researchers (non-MDs) (22.3 vs 16.3; P = .028). Conclusions Surgeon-scientists are equally productive and impactful compared with nonsurgeons despite decreasing funding rates at the National Institutes of Health and greater pressure from administrators to increase clinical productivity.

This work addresses the design and implementation of a wireless connection for the remote control of the joints of a redundant 3-DoF 1 manipulator robot. To this end, low-cost devices able to establish master/slave connections are used as closed control loops to calculate both control in the master device and actuation in the slave devices. To test the performance of this wireless connection, classic robot controllers are designed, simulated, analyzed, implemented, and compared through a decentralized structure. The platform Raspberry Pi and UDP 2 protocol are used to obtain and process data sent to the robot control system, and to send control signals to the robot actuators. Additionally, the feasibility of synthetizing control systems for highly non-linear robots and, in turn, of commanding this system through a remote wireless communication system is demonstrated.

Background Vasoplegic syndrome, defined by hypotension despite normal or increased cardiac output, is associated with high mortality rate after cardiopulmonary bypass. Methylene blue (MB) is reported to ameliorate vasoplegic syndrome through the nitric oxide pathway. We hypothesized that early administration of MB would improve outcomes in patients with vasoplegic syndrome after cardiopulmonary bypass. Methods All patients that underwent cardiopulmonary bypass at our institution (Jan 1, 2011 to Jun 30, 2016) were identified through our Society of Thoracic Surgery database. Pharmacy records identified patients receiving MB within 72 hours of cardiopulmonary bypass. Multivariate logistic regression identified predictors of major adverse events among patients receiving MB. Results A total of 118 cardiopulmonary bypass patients (3.3%) received MB for vasoplegic syndrome. These patients had a higher incidence of comorbidities, and these cases were more commonly reoperative (76.1% versus 41.2%, p Conclusions Operative mortality rate is high in patients receiving MB for the treatment of vasoplegia after cardiopulmonary bypass. Early administration of MB improves survival and reduces the risk-adjusted rate of major adverse events in these patients.

While it is anticipated that decubitus ulcers are detrimental to outcomes after vascular operations, the contemporary influence of perioperative decubitus ulcers in vascular surgery remains unknown.Using the National Impatient Survey, all adult patients who underwent vascular operation were selected. Patients were stratified by the presence or absence (non-decubitus ulcers) of decubitus ulcer. Case-mix adjusted hierarchical mixed-models examined in-hospital mortality, the occurrence of any complication, and discharge disposition.A total of 538,808 cases were analyzed. Decubitus ulcers were most prevalent among Caucasian male Medicare beneficiaries (P .001). Decubitus ulcer patients also underwent more nonelective vascular operations (P .001). Wound, infectious, and procedural complications were more common in patients with decubitus ulcers (P .001). Failure to rescue, defined as mortality after any complication, was more than doubled in decubitus ulcers (non-decubitus ulcers: 1.5%, decubitus ulcers: 3.2%, P .001). Similarly, unadjusted mortality was also doubled in patients undergoing vascular operation with decubitus ulcers (non-decubitus ulcers: 3%, decubitus ulcers: 6%, P .001). After risk adjustment among all patients, neither the presence of a decubitus ulcer nor specific ulcer staging increased the adjusted odds of death. Having a decubitus ulcer increased the adjusted odds of discharge to an intermediate care facility (odds ratio 2.9, P .001). These patients also had 1.6 times the total charges compared to their non-decubitus ulcer cohort (non-decubitus ulcers: $49,460 ± $281 vs decubitus ulcers: $81,149 ± $5,855, P .001).Contrary to common perception, perioperative decubitus ulcer does not adversely affect mortality after vascular operation in patients proceeding to operative intervention. Patients with decubitus ulcers are, however, at higher risk for complications and incur sizeable additional charges.

Objective United States Food and Drug Administration (FDA)-mandated postapproval studies have long been a mainstay of the continued evaluation of high-risk medical devices after initial marketing approval; however, these studies often present challenges related to patient/physician recruitment and retention. Retrospective single-center studies also do not fully represent the spectrum of real-world performance nor are they likely to have a sufficiently large enough sample size to detect important signals. In recent years, The FDA Center for Devices and Radiological Health has been promoting the development and use of patient registries to advance infrastructure and methodologies for medical device investigation. The FDA 2012 document, "Strengthening the National System for Medical Device Post-market Surveillance," highlighted registries as a core foundational infrastructure when linked to other complementary data sources, including embedded unique device identification. The Vascular Quality Initiative (VQI) thoracic endovascular aortic repair for type B aortic dissection project is an innovative method of using quality improvement registries to meet the needs of device evaluation after market approval. Here we report the organization and background of this project and highlight the innovation facilitated by collaboration of physicians, the FDA, and device manufacturers. Methods This effort used an existing national network of VQI participants to capture patients undergoing thoracic endovascular aortic repair for acute type B aortic dissection within a registry that aligns with standard practice and existing quality efforts. The VQI captures detailed patient, device, and procedural data for consecutive eligible cases under the auspices of a Patient Safety Organization (PSO). Patients were divided into a 5-year follow-up group (200 acute; 200 chronic dissections) and a 1-year follow-up group (100 acute; 100 chronic). The 5-year cohort required additional imaging details, and the 1-year group required standard VQI registry data entry. Results The sample size of patients in each of the 5-year acute and chronic dissection arms was achieved ≤24 months of project initiation, and data capture for the 1-year follow-up group is also nearly complete. Data completeness and follow-up has been excellent, and the two FDA-approved devices for dissection are equally represented. Conclusions Although the completeness of long-term follow-up is yet to be determined, the rapidity of data collection supports the use of this construct for device assessment after market approval. The alignment of this effort with routine clinical practice and ongoing quality improvement initiatives is critical and has required minimal additional effort by practitioners, thus facilitating patient inclusion. Importantly, the success and development of this unique project has helped inform FDA strategy for future device evaluation after market approval.

Background Carotid endarterectomy (CEA) is a commonly performed vascular operation. Yet, postoperative length of stay (LOS) varies greatly even within institutions. In this study, the morbidity and mortality, as well as financial impact of increased LOS were reviewed to establish modifiable factors associated with prolonged hospital stay. Methods The Society for Vascular Surgery Vascular Quality Initiative database was used to identify all patients undergoing primary CEA at a single institution between June 1, 2011 and November 28, 2014. Preoperative patient characteristics, intraoperative details, postoperative factors, long-term outcomes, and cost data were reviewed using an Institutional Review Board-approved prospectively collected database. Multivariate analysis was used to determine statistical difference between patients with LOS ≤1 day and >1 day. Results Complete 30-day variable and cost data were available for 219 patients with an average follow-up of 12 months. Seventy-nine (36%) patients had an LOS > 1 day. Variables determined to be statistically significant predictors of prolonged LOS included preoperative creatinine (P = 0.02) and severe congestive heart failure (P = 0.05) with self-pay status (P = 0.02) and preoperative beta-blocker therapy (P = 0.04) being protective. Shunt placement (P = 0.04), arterial re-exploration, and postoperative cardiac (P = 0.001) or neurological (P = 0.03) complications also resulted in prolonged hospitalization. Specific modifiable risk factors that contributed to increased LOS included operative start time after noon (P = 0.04), drain placement (P = 0.05), prolonged operative time (101 vs. 125 min, P = 0.01), return to the operating room (P = 0.01), and postoperative hypertension (P = 0.02) or hypotension (P = 0.04). Of note, there was no difference in LOS associated with technique (conventional versus eversion), patch use (P = 0.49), protamine administration (P = 0.60), electroencephalogram monitoring (P = 0.45), measurement of stump pressure (P = 0.63), Doppler (P = 0.36), or duplex (P = 0.92). Both hospital charges (P = 0.0001) and costs (P = 0.0001) were found to be significantly higher in patients with prolonged LOS, with no difference in physician charges (P = 0.10). Increased LOS after CEA was associated with an increase in 12-month mortality (P = 0.05). Conclusions Increased LOS was associated with increased hospital charges, costs, as well as significant morbidity and midterm mortality following CEA. Furthermore, this study highlights several modifiable risk factors leading to increased LOS. Identified factors associated with increase LOS can serve as targets for improving care in vascular surgery.

Modbus-RTU is currently one of the most widely-used industrial communications protocols. Modbus-RTU is an old protocol – it was developed in 1979 – and has certain limitations with regard to modern automation and control systems. One of the major limitations is that the protocol does not have any mechanisms for ensuring the integrity of transmitted data. To address the limitation, this paper presents a method for recovering corrupted frames due to transmission errors in Modbus-RTU serial communications while retaining complete compatibility with the protocol. The method uses forward error correction codes that add parity information in time windows during which the communications bus is in a rest state. The method complies with the protocol definitions and facilitates the extension of Modbus-RTU characteristics while maintaining compatibility with installed devices and other industrial equipment.

Utilization of a left ventricular assist device as a bridge to myocardial recovery is an established therapy for acute systolic heart failure. However, device removal can present a technical challenge, with no clear consensus on preferred method. In this case report, we describe a complex patient who underwent successful explantation of a left ventricular assist device using an intraoperatively constructed apical plug. This method utilizes inexpensive and easily accessible materials, minimizes ventricular distortion during device removal, and preserves the ventricular sewing ring for future reimplantation.

Medical therapy for mycotic aortic aneurysms (MAA) is almost universally fatal, while surgical and endovascular repair carry high morbidity and mortality. The purpose of this study was to compare outcomes between patients receiving treatment for MAA. Records were obtained and patients with MAA were stratified by intervention: endovascular repair, open surgery, and medical therapy. Primary outcomes were aneurysm-related mortality and survival. Risk-adjusted associations with mortality were assessed using time-to-event analysis. Thirty-eight patients were identified (median age, 67). Twenty-one underwent endovascular repair,10 had open surgery and 7 received medical therapy alone. Overall mortality was 47% (n = 18), with 94% aneurysm related. Median survival was significantly longer in the endovascular group (747.0 [161-1249]) vs open surgery and medical therapy (507.5 [34-806] and 66 [13-146] days, respectively; P = .02). The endovascular group had significantly fewer perioperative complications (43% vs 80%, P < .01). However, 4 endovascular patients experienced reinfection versus no open surgery patients. Mortality risk factors included medical therapy (hazard ratio [HR]: 5.3, P < .01) and aneurysm size (HR: 1.4 per 1-cm increase in diameter, P = .03). Endovascular repair of MAA was associated with the best long-term survival and lowest perioperative complication rate, although it is associated with greater reinfection. These tradeoffs should be considered when selecting which procedure is best for a patient.

Many patients with aortic dissection develop Crawford extent I or II thoracoabdominal aortic aneurysms (TAAA). Because open repair is associated with a high morbidity and mortality, hybrid approaches to TAAA repair are emerging. In this study, we evaluated the midterm outcomes and aortic remodeling of a hybrid technique that combines proximal thoracic endovascular aneurysm repair (TEVAR), followed by staged distal open thoracoabdominal repair for patients with Crawford extent I or II TAAAs secondary to chronic aortic dissection.We identified 19 patients with Crawford extent I (n = 1) or extent II (n = 18) TAAAs secondary to chronic aortic dissection who underwent a staged hybrid repair from 2007 to 2014 at our institution. Nine patients had previous open ascending aortic surgery for type I aortic dissection. Stage 1 TEVAR was performed via percutaneous (n = 8), femoral cutdown (n = 8), or iliac exposure (n = 3). The left subclavian artery was covered in nine patients and revascularized in eight patients using carotid-subclavian bypass (n = 7) or laser fenestration (n = 1). Stage 2 open repair was performed a median of 18 weeks later with partial cardiopulmonary bypass via left femoral arterial and venous cannulation for visceral and lower body perfusion. The open thoracoabdominal graft was anastomosed proximally in an end to end fashion with the endograft. We then assessed surgical morbidity and mortality, midterm survival, and freedom from reintervention. Aortic remodeling was measured and change in maximum aortic and false lumen diameter at last follow-up (median, 3 years) from baseline was assessed.There were no deaths, strokes, or chronic renal failure in this cohort. After stage 1 TEVAR, three patients required repeat intervention for endoleak (type Ia, n = 1; type Ib, n = 1; type II, n = 1) before open repair. After stage 2 open repair, there was a single delayed permanent paralysis 2 weeks after discharge. At a median 3-year follow-up (range, 6 months-6.2 years), there were no deaths, neurologic events, endoleaks, or TAAA reinterventions. Complete false lumen thrombosis occurred in 100% of the patients, with maximum false lumen diameter decreasing from 34.3 ± 15.3 mm to 13.2 ± 12.0 mm (P.01) and total aortic diameter decreasing from 60.2 ± 9.0 mm to 49.4 ± 9.6 mm (P.01).Staged hybrid TAAA repair, using a combination of proximal TEVAR with open distal repair, can be performed using established endovascular skills and technology coupled with traditional open aortic surgical techniques, with low surgical morbidity and mortality. In the midterm, staged hybrid TAAA repair was associated favorable survival, aortic remodeling, and freedom from reintervention.

Modeling, control and implementation of a real redundant robot with five Degrees Freedom (DOF) of the SCARA (Selective Compliant Assembly Robot Arm) manipulator type is presented. Through geometric methods and structural and functional considerations, the inverse kinematics for redundant robot can be obtained. By means of a modification of the classical sliding mode control law through a hyperbolic function, we get a new algorithm which enables reducing the chattering effect of the real actuators, which together with the learning and adaptive controllers, is applied to the model and to the real robot. A simulation environment including the actuator dynamics is elaborated. A 5 DOF robot, a communication interface and a signal conditioning circuit are designed and implemented for feedback. Three control laws are executed in: a simulation structure (together with the dynamic model of the SCARA type redundant manipulator and the actuator dynamics) and a real redundant manipulator of the SCARA type carried out using MatLab/Simulink programming tools. The results, obtained through simulation and implementation, were represented by comparative curves and RMS indices of the joint errors, and they showed that the redundant manipulator, both in the simulation and the implementation, followed the test trajectory with less pronounced maximum errors using the adaptive controller than the other controllers, with more homogeneous motions of the manipulator.

Endovascular aneurysm repair (EVAR) is a commonly performed vascular operation. Yet, postoperative length of stay (LOS) varies greatly, even within institutions. The present study reviewed the morbidity, mortality, and the financial effect of increased LOS to establish modifiable factors associated with prolonged hospital LOS, with the goal of improving quality.The Society for Vascular Surgery Vascular Quality Initiative database was used to identify all patients undergoing primary, elective EVAR at a single institution between January 1, 2011, and May 28, 2014. Preoperative patient characteristics, intraoperative details, postoperative factors, long-term outcomes, and cost data were reviewed using an Institutional Review Board-approved prospectively collected database. Multivariate analysis was used to determine statistical difference between patients with LOS ≤2 days and2 days.Complete 30-day variable and cost data were available for 138 patients with an average follow-up of 12 months; of these, 46 (33%) had a LOS2 days. Variables determined to be statistically significant predictors of prolonged LOS included aneurysm diameter (P = .03), American Society of Anesthesiologists Physical Status Classification score (P.001), thromboembolectomy (P = .01), and increased postoperative cardiac (P.001) and renal (P = .01) complications. Specifically, modifiable risk factors that contributed to increased LOS included performance of a concomitant procedure (P.001), increased volume of iodinated contrast (P = .05), increased volume of intraoperative crystalloid (P = .05), placement in an intensive care unit (P.001), return to the operating room (P.001), and the use of vasoactive medications (P.001). Hospital charges ($102,000 ± $41,000 vs $180,000 ± $73,000; P = .01) and costs ($27,000 ± $10,000 vs $45,000 ± $19,000 P = .01) were significantly higher in patients with prolonged LOS; however, there was no difference in physician charges ($8000 ± $5700 vs $12,000 ± $12,000; P = .09). Increased LOS after EVAR was associated with an increase in mortality at 1 month (0% vs 4% P = .05) and 12 months (3% vs 13% P = .03).This study highlights several modifiable risk factors leading to increased LOS after EVAR, including performance of concomitant procedures, admission to the intensive care unit, and postoperative renal and cardiac complications. Further, increased LOS was associated with increased charges, costs, morbidity, and mortality after EVAR. This study highlights specific areas of focus for decreasing LOS after EVAR and, in turn, improving quality in vascular surgery.

This paper presents the development of a convolutional code application for error detection and correction in a communication system. This application is based on an industrial protocol and aims at reconstructing data damaged during transmission. The Controller Area Network (CAN) protocol is used, which is widely used in the automobile industry, as well as in the automation of industrial processes. The application allows us to make a system that presents errors due to hostile conditions in the fault-tolerant industrial environment. These errors appear as corrupted data affecting the robot’s control system. The robot is a 3 Degrees of Freedom (3-DoF) manipulator robot with redundancy in the plane; data transmission takes place between the controller and such a robot. The communication system is assessed in terms of performance when facing transmission faults, comparing the response of the system with and without error correction.

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.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.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% DCI75; 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).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.

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.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.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).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.

Obtaining National Institutes of Health (NIH) funding over the last 10 years has become increasingly difficult due to a decrease in the number of research grants funded and an increase in the number of NIH applications.National Institutes of Health funding amounts and success rates were compared for all disciplines using data from NIH, Federation of American Societies for Experimental Biology (FASEB), and Blue Ridge Medical Institute. Next, all NIH grants (2006 to 2016) with surgeons as principal investigators were identified using the National Institutes of Health Research Portfolio Online Reporting Tools Expenditures and Results (NIH RePORTER), and a grant impact score was calculated for each grant based on the publication's impact factor per funding amount. Linear regression and one-way ANOVA were used for analysis.The number of NIH grant applications has increased by 18.7% (p = 0.0009), while the numbers of funded grants (p0.0001) and R01s (p0.0001) across the NIH have decreased by 6.7% and 17.0%, respectively. The mean success rate of funded grants with surgeons as principal investigators (16.4%) has been significantly lower than the mean NIH funding rate (19.2%) (p = 0.011). Despite receiving only 831 R01s during this time period, surgeon scientists were highly productive, with an average grant impact score of 4.9 per $100,000, which increased over the last 10 years (0.15 ± 0.05/year, p = 0.02). Additionally, the rate of conversion of surgeon scientist-mentored K awards to R01s from 2007 to 2012 was 46%.Despite declining funding over the last 10 years, surgeon scientists have demonstrated increasing productivity as measured by impactful publications and higher success rates in converting early investigator awards to R01s.

The American Psychiatric Association Integrated Care Workgroup recently convened an expert panel charged with addressing the role of psychiatry in improving the physical health of persons with serious mental illness. The group reviewed the peer-reviewed and gray literature and developed a set of recommendations grounded in this review. This column summarizes the panel's primary findings and recommendations to key stakeholders, including clinicians, health care organizations, researchers, and policy makers.

Primary care clinics are increasingly implementing collaborative care models to care for patients with psychiatric illnesses in primary care. The evidence base for the effectiveness of collaborative care has largely been derived from the care of patients with depression or anxiety disorders, although psychiatrists working in primary care may encounter patients with illnesses other than depression or anxiety disorder, notably bipolar disorder. Patients with bipolar disorder report having received treatment in primary care in equal proportions as those in specialty care settings over the past 12 months, although quality of care is lower in primary care than in specialty care settings. For patients already presenting to primary care, collaborative care is one population-based care model that may increase the proportion of individuals with bipolar disorder who are exposed to high-quality psychiatric care, such as appropriate medication treatment and laboratory monitoring. The primary care setting may even present unexpected strengths in caring for patients with bipolar disorder. Solutions to barriers to expanding the scope of collaborative care to include patients with bipolar disorder may apply to the care of patients with other complex disorders in the primary care setting.

Background Thrombosis within a left ventricular assist device (LVAD) is a devastating complication that often necessitates device exchange. Few studies have evaluated the relationship between patient anatomy and pump thrombosis. We hypothesize that lateral displacement of the left ventricular (LV) apex increases risk for pump thrombosis. Methods All patients who underwent primary implantation of a HeartMate II (HM2) device (Thoratec, Pleasanton, CA) at a single center (2009-2015) were evaluated. Operative mortalities and patients without imaging were excluded. The angle of the LV apex relative to the midline was measured on preoperative computed tomography scans by two independent surgeons. Pump thrombosis was defined as lactic dehydrogenase >700 with clinical symptoms of hemolysis or LVAD malfunction. Univariate and Cox Proportional Hazards analysis was performed to evaluate the impact of LV apex angle on long-term freedom from pump exchange for thrombosis. Results Of 122 patients who met inclusion criteria for this study, 16 (13.1%) underwent exchange for presumed pump thrombosis. Of these patients, six (37.5%) required more than one exchange. Patients undergoing exchange for thrombosis had greater LV angle (43.8 ± 9.7 vs 49.5 ± 11.2, p = 0.037) with LV apex angle being a significant predictor of LVAD exchange for thrombosis (hazard ratio = 1.047, P = 0.046). Additionally, when surgeon measurements were compared there was good inter-observer reliability (Pearson Correlation = 0.89). Conclusion A laterally displaced left ventricular apex correlates with a higher risk of pump thrombosis in patients undergoing HM2 implantation. LV apex angle is an easily obtained, reproducible measurement that should be considered when selecting a ventricular assist device.

Background Policymakers have proposed risk-adjusted bundled payment as the single most promising method of linking reimbursement to value rather than to quantity of service. Our objective was to assess the relationship between risk and cost to develop a model for forecasting the costs of cardiac operations under a bundled payment scheme. Methods All patients undergoing adult cardiac operations for which there was a Society of Thoracic Surgeons (STS) risk score over a 5-year period (2008 to 2013) at a tertiary care, university hospital were reviewed. Patients were stratified into five groups based on preoperative risk as a basis for negotiating risk-adjusted bundles. A multivariable regression model was developed to analyze the relationship between risk and log-transformed costs. Monte Carlo simulation was performed to validate the model by comparing predicted with actual fiscal year 2013 costs. Results Among the 2,514 patients analyzed, preoperative risk was strongly correlated with costs ( p R 2 = 0.28) of the variation in costs between individual patients. The use of bundling to diffuse and adjust for risk improved prediction to only 33% ( R 2 = 0.33). Actual costs in 2013 were $21.6M compared with predicted costs of $19.3M (±$350K), which is well outside the forecast's 95% confidence interval. Conclusions Even among the most routine cardiac operations and with use of the most widely validated surgical risk score available, much of the variation in costs cannot be explained by preoperative risk or surgeon. Consequently, policymakers should reexamine whether individual practices or insurers are best suited to manage the residual financial risk.

Several single-center studies have reported excellent outcomes with minimally invasive aortic valve replacement (mini-AVR). Although criticized as requiring more operative time and complexity, mini-AVR is increasingly performed. We compared contemporary outcomes and cost of mini-AVR versus conventional AVR in a multi-institutional regional cohort. We hypothesized that mini-AVR provides equivalent outcomes to conventional AVR without increased cost.Patient records for primary isolated AVR (2011-2013) were extracted from a regional, multi-institutional Society of Thoracic Surgeons database and stratified by conventional versus mini-AVR, performed by either partial sternotomy or right thoracotomy. To compare similar patients, a 1:1 propensity-matched cohort was performed after adjusting for surgeon; operative year; and Society of Thoracic Surgeons risk score, including age and risk factors (n = 289 in each group). Differences in outcomes and cost were analyzed.A total of 1341 patients underwent primary isolated AVR, of which 442 (33%) underwent mini-AVR at 17 hospitals. Mortality, stroke, renal failure, and other major complications were equivalent between groups. Mini-AVR was associated with decreased ventilator time (5 vs 6 hours; P = .04) and decreased blood product transfusion (25% vs 32%; P = .04). A greater percentage of mini-AVR patients were discharged within 4 days of the operation (15.2% vs 4.8%; P.001). Consequently, total hospital costs were lower in the mini-AVR group ($36,348 vs $38,239; P = .02).Mortality and morbidity outcomes of mini-AVR are equivalent to conventional AVR. Mini-AVR is associated with decreased ventilator time, blood product use, early discharge, and reduced total hospital cost. In contemporary clinical practice, mini-AVR is safe and cost-effective.

Objective For descending thoracic aortic aneurysms (TAAs), it is generally considered that thoracic endovascular aortic repairs (TEVARs) reduce operative morbidity and mortality compared with open surgical repair. However, long-term differences in survival of patients have not been demonstrated, and an increased need for aortic reintervention has been observed. Many assume that TEVAR becomes less cost-effective through time because of higher rates of reintervention and surveillance imaging. This study investigated midterm outcomes and hospital costs of TEVAR compared with open TAA repair. Methods This was a retrospective, single-institution review of elective TAA repairs between 2005 and 2012. Patient demographics, operative outcomes, reintervention rates, and hospital costs were assessed. The literature was also reviewed to determine commonly observed complication and reintervention rates for TEVAR and open repair. Monte Carlo simulation was used to model and to forecast hospital costs for TEVAR and open TAA repair up to 3 years after intervention. Results Our cohort consisted of 131 TEVARs and 27 open repairs. TEVAR patients were significantly older (67.2 vs 58.7 years old; P = .02) and trended toward a more severe comorbidity profile. Operative mortality for TEVAR and open repair was 5.3% and 3.7%, respectively ( P = 1.0). There was a trend toward more complications in the TEVAR group, although not statistically significant (all P > .05). In-hospital costs were significantly greater in the TEVAR group ($52,008 vs $37,172; P = .001). However, cost modeling by use of reported complication and reintervention rates from the literature overlaid with our cost data produced a higher cost for the open group in-hospital ($55,109 vs $48,006) and at 3 years ($58,426 vs $52,825). Interestingly, TEVAR hospital costs, not reintervention rates, were the most significant driver of cost in the TEVAR group. Conclusions Our institutional data showed a trend toward lower mortality and complication rates with open TAA repair, with significantly lower costs within this cohort compared with TEVAR. These findings were likely, at least in part, to be due to the milder comorbidity profile of these patients. In contrast, cost modeling by Monte Carlo simulation demonstrated lower costs with TEVAR compared with open repair at all time points up to 3 years after intervention. Our institutional data show that with appropriate selection of patients, open repair can be performed safely with low complication rates comparable to those of TEVAR. The cost model argues that despite the costs associated with more frequent surveillance imaging and reinterventions, TEVAR remains the more cost-effective option even years after TAA repair.

Background and Aim of Study The purpose of this study was to examine whether blood product utilization, one-year cell-mediated rejection rates, and mid-term survival significantly differ for ventricular assist device (VAD patients compared to non-VAD (NVAD) patients following cardiac transplantation. Methods From July 2004 to August 2011, 79 patients underwent cardiac transplantation at a single institution. Following exclusion of patients bridged to transplantation with VADs other than the HeartMate II® LVAD (n = 10), patients were stratified by VAD presence at transplantation: VAD patients (n = 35, age: 54.0 [48.0–59.0] years) vs. NVAD patients (n = 34, age: 52.5 [42.8–59.3] years). The primary outcomes of interest were blood product transfusion requirements, one-year cell-mediated rejection rates, and mid-term survival post-transplantation. Results Preoperative patient characteristics were similar for VAD and NVAD patients. NVAD patients presented with higher median preoperative creatinine levels compared to VAD patients (1.3 [1.1–1.6] vs. 1.1 [0.9–1.4], p = 0.004). VAD patients accrued higher intraoperative transfusion of all blood products (all p ≤ 0.001) compared to NVAD patients. The incidence of clinically significant cell-mediated rejection within the first posttransplant year was higher in VAD compared to NVAD patients (66.7% vs. 33.3%, p = 0.02). During a median follow-up period of 3.2 (2.0, 6.3) years, VAD patients demonstrated an increased postoperative mortality that did not reach statistical significance (20.0% vs. 8.8%, p = 0.20). Conclusions During the initial era as a bridge to transplantation, the HeartMate II® LVAD significantly increased blood product utilization and one-year cell-mediated rejection rates for cardiac transplantation. Further study is warranted to optimize anticoagulation strategies and to define causal relationships between these factors for the current era of cardiac transplantation. doi: 10.1111/jocs.12474 (J Card Surg 2015;30:194–200)

The MitraClip REALISM (Abbott Vascular, Menlo Park, CA) trial included several inclusion criteria to identify patients at high risk for conventional mitral valve (MV) surgery. This study evaluated contemporary surgical outcomes for high-risk surgical patients who met these defined criteria to serve as a benchmark to evaluate appropriateness in treatment allocation between surgical and percutaneous MV repair.A statewide Society for Thoracic Surgeons (STS) database was queried for patients undergoing isolated mitral valve surgery over a 12-year study period from 17 different hospitals. Patients were stratified into high-risk (HR) versus non-high-risk (non-HR) cohorts based upon clinical criteria similar to those utilized in the REALISM trial. Mixed effects multivariable regression modeling was used to evaluate study endpoints including mortality, morbidity, and resource utilization.Of 2,440 isolated mitral operations, 29% (n = 698) were HR per REALISM criteria. Median STS Predicted Risk of Mortality (PROM) for HR patients was 6.6% compared with 1.6% for non-HR patients (p0.001). The HR patients more commonly underwent MV replacement as well as urgent (30% vs 19%, p0.001) operations. High-risk patients incurred higher morbidity and mortality (7% vs 1.6%) with longer intensive care unit (48 vs 41 hours) and hospital stays (7 vs 6 days, all p0.001). Among REALISM criteria, STS PROM 12% or greater and high-risk STS criteria were the only criteria associated with mortality.Select REALISM criteria, including reoperation with patent grafts and functional MR with ejection fraction less than 0.40, may not identify patients truly at high risk of death with surgery. In addition to conventional STS criteria, risk assessment by surgeons is essential to direct appropriate treatment allocation for high-risk mitral disease.

Transcatheter valve placement complicated by left ventricular embolization is often treated with sternotomy, valve removal through the aorta, and conventional aortic valve replacement. We report three cases of ventricular embolization of aortic valves during deployment. We successfully placed a second transcatheter aortic valve in the correct position and retrieved the embolized valve through an apical ventriculotomy. All patients recovered well and survived for more than one year. doi: 10.1111/jocs.12701 (J Card Surg 2016;31:203-205).

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.

Dementia represents a major risk factor for medical complications and has been linked to higher rates of complication after surgery. Given the systemic nature of vascular disease, medical comorbidities significantly increase cost and complications after vascular surgery. We hypothesize that the presence of dementia is an independent predictor of increased postoperative complications and higher health care costs after vascular surgery.The Vascular Quality Initiative database was queried for all patients undergoing vascular surgery at a single academic medical center from 2012 to 2017. All modules were included (open abdominal aortic aneurysm, suprainguinal bypass, lower extremity bypass, amputation, carotid endarterectomy, endovascular aortic aneurysm repair, thoracic endovascular aortic aneurysm repair, and peripheral endovascular intervention). An institutional clinical data repository was queried to identify patients with International Classification of Diseases, Ninth Revision diagnosis codes for dementia as well as total hospital cost and long-term survival using Social Security records from the Virginia Department of Health. Hierarchical logistic and linear regression models were fit to assess risk-adjusted predictors of any complication and inflation-adjusted cost. Kaplan-Meier and Cox proportional hazards models were used for survival analysis.A total of 2318 patients underwent vascular surgery and were captured by the Vascular Quality Initiative during the past 5 years, with 88 (3.8%) having a diagnosis of dementia. Patients with dementia were older and had higher rates of medical comorbidities, and the most common procedure was major amputation. In addition, dementia patients had a significantly higher rate of any complication (52% vs 16%; P .0001) and increased 90-day mortality (14% vs 4.8%; P = .0002). Furthermore, dementia was associated with significant resource utilization, including preoperative length of stay (LOS), postoperative LOS, intensive care unit LOS, and inflation-adjusted total hospital cost (all P .0001). Hierarchical modeling demonstrated that dementia was the strongest preoperative predictor for any complication (odds ratio, 8.64; P .0001) and had the largest risk-adjusted impact on total hospital cost ($22,069; P .0001). Finally, survival analysis demonstrated that dementia is independently associated with reduced survival after vascular surgery (hazard ratio, 1.37; P = .018).This study demonstrated that dementia is one of the strongest predictors of any complication and increased hospital cost after vascular surgery. Given the high risk of clinical and financial maladies, patients with dementia should be carefully considered and counseled before undergoing vascular surgery.

OBJECTIVES: Minimally invasive mitral valve surgery (mini-MVR) has numerous associated benefits. However, many studies fail to include higher risk patients. We hypothesized that a minimally invasive approach in a representative cohort provides excellent outcomes with reduced resource utilization. METHODS: Mitral valve surgical records from 2011-2016 were paired with institutional financial records. Patients were stratified by approach and propensity-score matched to balance preoperative difference. The primary outcomes of interest were resource utilization including cost, discharge to a facility, and readmission. RESULTS: A total of 478 patients underwent mitral surgery (21% mini-MVR) and were balanced after matching (n=74 per group) with 18% of patients having non-degenerative mitral disease. Outcomes were excellent with similar rates of major morbidity (9.5% mini-MVR vs 10.8% conventional, p=0.78). Mini-MVR cases had lower rates of transfusion (11% vs 27%, p=0.01) and shorter ventilator times 3.7 vs 6.0 hrs (p