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Background: Coronary artery occlusion (CO) during transcatheter aortic valve replacement (TAVR) is a devastating complication. The objective of this study was to assess the clinical impact of a computational predictive modeling algorithm for CO during TAVR planning., Methods: From January 2020 to December 2022, 116 patients (7.6%) who underwent TAVR evaluation were deemed to be at increased risk of CO on the basis of traditional criteria. Patients underwent prospective computational modeling (DASI Simulations) to assess their risk of CO during TAVR; procedural modifications and clinical results were reviewed retrospectively., Results: Of the 116 patients at risk for CO by traditional methodology, 53 had native aortic valve stenosis (45.7%), 47 had undergone previous surgical AVR (40.5%), and 16 had undergone previous TAVR (13.8%). Transcatheter valve choice, size, or implantation depth was modeled for all patients. Computational modeling predicted an increased risk of CO in 39 of 116 (31.9%) patients. Within this subcohort, 29 patients proceeded with TAVR. Procedural modifications to augment the risk of CO included bioprosthetic or native aortic scallop intentional laceration to prevent iatrogenic coronary artery obstruction during TAVR (n = 10), chimney coronary stents (n = 8), and coronary access without stents (n = 3). There were no episodes of coronary artery compromise among patients after TAVR, either for those predicted to be at high risk of CO (with procedural modifications) or those predicted to be at low risk (standard TAVR)., Conclusions: The use of preoperative simulations for TAVR in patient-specific geometry through computational predictive modeling of CO is an effective enhancement to procedure planning., Competing Interests: Disclosures Taylor Becker reports a relationship with DASI Simulations that includes: consulting or advisory. Pradeep Yadav reports a relationship with Edwards Lifesciences that includes: consulting or advisory and speaking and lecture fees; with Abbott Vascular that includes: consulting or advisory and speaking and lecture fees; with Boston Scientific that includes: consulting or advisory; with DASI Simulations that includes: equity or stocks; with Edwards Lifesciences that includes: funding grants; with Abbott Vascular that includes: funding grants; with Boston Scientific that includes: funding grants; with Medtronic that includes: funding grants; with JenaValve Technology that includes: funding grants; with Trisol Medical that includes: funding grants; with HighLife that includes: funding grants; with Innovalve that includes: funding grants; and with CroiValve that includes: funding grants. Vivek Rajagopal reports a relationship with Opus Medical Therapies that includes: equity or stocks. Venkateshwar Polsani reports a relationship with DASI Simulations that includes: board membership. Lakshmi Prasad Dasi reports a relationship with DASI Simulations that includes: board membership and equity or stocks; and reports holding patent PCT/US2022/072784. Vinod H. Thourani reports a relationship with Abbott Vascular that includes: consulting or advisory and speaking and lecture fees; with Artivion that includes: consulting or advisory and speaking and lecture fees; with AtriCure that includes: consulting or advisory; with Boston Scientific that includes: consulting or advisory; with CroiValve that includes: consulting or advisory; with Edwards Lifesciences that includes: funding grants; with JenaValve Technology that includes: consulting or advisory and speaking and lecture fees; with DASI Simulations that includes: equity or stocks; with Abbott Vascular that includes: funding grants; with Artivion that includes: funding grants; with AtriCure that includes: funding grants; with Boston Scientific that includes: funding grants; with CroiValve that includes: funding grants; with Edwards Lifesciences that includes: funding grants; with Medtronic that includes: funding grants; and with Trisol that includes: funding grants. All other authors declare that they have no conflicts of interest to disclose., (Copyright © 2024 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Aortic stenosis (AS) contributes to significant cardiovascular morbidity and mortality worldwide, and the natural history from symptoms to ventricular decompensation, heart failure, and death has been well documented. For more than 2 decades, technologies including imaging and biomarkers have shown a promising ability to detect myocardial damage associated with AS before symptoms arise. Current treatment guidelines rely heavily on symptoms or ventricular decompensation as triggers for aortic valve intervention. There is increasing appreciation of the relationship between myocardial damage due to AS before the emergence of symptoms, and a number of published randomised trials suggest a benefit to early intervention in asymptomatic AS, with additional trials actively enrolling. Future treatment paradigms may incorporate early detection of ventricular damage by noninvasive new technologies as triggers for asymptomatic intervention. Enthusiasm for early aortic valve replacement should be tempered by consideration of the competing risks of early valve intervention, but an increasing preponderance of evidence continues to suggest that earlier intervention in AS is warranted., (Copyright © 2023 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

Competing Interests: Disclosures Dr Thourani reports the following relationships: Abbott Vascular (consulting or advisory); Artivion, Inc. (consulting or advisory); Boston Scientific Corp (consulting or advisory); Dasi Simulations (consulting or advisory); Edwards Lifesciences Corporation (consulting or advisory); JenaValve Technology Inc (consulting or advisory); and Medtronic (consulting or advisory).

Background: At the recent 6th World Symposium on Pulmonary Hypertension (PH), the definition of PH was redefined to include lower pulmonary artery pressures in the setting of elevated pulmonary vascular resistance (PVR). However, the relevance of this change to subjects with PH due to left-heart disease as well as the preoperative assessment of heart transplant (HT) recipients is unknown., Methods: The United Network for Organ Sharing database was queried to identify adult recipients who underwent primary HT from 1996 to 2015. Recipients were subdivided into those with mean pulmonary artery pressure (mPAP) < 25 mm Hg and ≥ 25 mm Hg. Exploratory univariable analysis was undertaken to identify candidate risk factors associated with 30-day and 1-year survival (conditional on 30-day survival) in recipients with mPAP < 25 mm Hg, and subsequently, parsimonious multivariable Cox proportional hazards models were constructed to assess the independent association with PVR., Results: Over the study period, 32,465 patients underwent HT, including 12,257 (38%) with mPAP < 25 mm Hg. The median age was 55 years (interquartile range, 47-62) and the median PVR was 1.5 Wood units (WU) (interquartile range, 1-2.2) in recipients with mPAP < 25 mm Hg. After controlling for confounders, PVR was independently associated with increased risk for 30-day mortality (hazard ratio, 1.16; 95% CI, 1.05-1.27; P < .01), but not conditional 1-year mortality (hazard ratio, 1.03; 95% CI, 0.94-1.12; P = .55). PVR ≥ 3 WU was associated with an absolute 1.9% increase in 30-day mortality in those with mPAP < 25 mm Hg, a similar risk to recipients with PVR ≥ 3 WU and mPAP ≥ 25 mm Hg., Conclusions: Elevated PVR remains associated with a significant increase in the hazard for 30-day mortality after cardiac transplantation, even in the setting of lower pulmonary artery pressures. These data support the validity of the new definition of pulmonary hypertension., (Copyright © 2019 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.)

Background: Bilateral internal mammary artery (BIMA) grafting in diabetic patients undergoing coronary artery bypass grafting remains controversial. Our study compared morbidity and mortality between (1) diabetic and nondiabetic BIMA patients and (2) diabetic BIMA versus diabetic patients who underwent left internal mammary artery (LIMA) grafting only., Methods: Patients who underwent isolated coronary artery bypass grafting from July 2011 to June 2016 at any of the 10 Maryland Cardiac Surgery Quality Initiative centers were propensity scored across 16 variables. Diabetic BIMA patients were matched 1:1 by nearest neighbor matching to nondiabetic BIMA patients and were separately matched 1:1 to diabetic LIMA patients. We calculated observed-to-expected (O/E) ratios for composite morbidity/mortality, operative mortality, unplanned reoperation, stroke, renal failure, prolonged ventilation, and deep sternal wound infection and compared ratios among matched populations., Results: During the study period, 812 coronary artery bypass grafting patients received BIMA grafts, including 302 patients (37%) with diabetes. We matched 259 diabetic and nondiabetic BIMA patients. O/E ratios were higher in matched diabetic (versus nondiabetic) BIMA patients when comparing composite morbidity/mortality, reoperation, stroke, renal failure, and prolonged ventilation (all O/E ratios >1.0); however, the O/E ratio for operative mortality was higher in nondiabetic BIMA patients. We additionally matched 292 diabetic BIMA to diabetic LIMA patients. Diabetic BIMA patients had a higher O/E ratio for composite morbidity/mortality, operative mortality, stroke, renal failure, and prolonged ventilation., Conclusions: In this statewide analysis, diabetic patients who received BIMA grafts (compared with diabetic patients with LIMA grafts or nondiabetic patients with BIMA grafts) had higher O/E ratios for composite morbidity/mortality as a result of higher O/E ratios for major complications., (Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Concern has been raised over inferior lung transplantation survival associated with traumatic brain injury (TBI) organ donors. Our purpose was to explore the relationship between TBI donors and lung transplantation survival in the lung allocation score (LAS) era., Methods: We queried the United Network for Organ Sharing Scientific Registry of Transplant Recipients and identified all adult (≥18 years) lung transplantations performed from May 4, 2005, to December 31, 2015. Recipients were dichotomized based on donor cause of death, TBI versus non-TBI, propensity score across eight variables (final LAS, intensive care unit admission before transplantation, extracorporeal membrane oxygenation before transplantation, donor age 50 years or older, cytomegalovirus antibody recipient - /donor + , ischemia time, annual center transplantation volume, single versus double lung transplantation), and matched 1:1 without replacement. Our primary outcomes were survival at 1, 3, and 5 years by Kaplan-Meier method., Results: A total of 17,610 patients underwent isolated lung transplantation over the study period at 75 different transplantation centers. TBI was the leading cause of death in the donor population: 47% of all donors. Propensity score matching generated 6,782 well-matched donor TBI versus non-TBI pairs (all covariate p > 0.2). Risk-adjusted survival was similar between recipients of TBI donors versus non-TBI donors at 1 year (86% versus 86%, log-rank p = 0.27), 3 years (68% versus 68%, log-rank p = 0.47), and 5 years (55% versus 54%, log-rank p = 0.40)., Conclusions: In the largest analysis of TBI donors and the impact on lung transplantation survival to date, we found similar survival out to 5 years in lung transplant recipients of TBI versus non-TBI donors, alleviating concerns over continued transplantation with this unique donor population., (Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Although tricuspid valve detachment (TVD) facilitates improved exposure during transatrial ventricular septal defect (VSD) closure, few have analyzed the impact of TVD on long-term valve durability., Methods: Pediatric patients undergoing VSD closure at our institution from 1997 to 2013 were identified, and charts were retrospectively reviewed. Patients were separated into groups based on utilization of TVD. Propensity score matching was then performed using a nonparsimonious logistic regression model involving 7 variables. Primary outcome was residual TV dysfunction at long-term follow-up, defined as mild (2+) and moderate (3+) TV regurgitation (TR) on follow-up echocardiography. Secondary outcomes included postoperative atrioventricular dissociation, residual VSD, and reinterventions., Results: A total of 247 patients underwent VSD closure; 164 (66.4%) without TVD and 83 (33.6%) with TVD. Median follow-up time was 2,343 days (interquartile range, 1,237 to 3,963.5 days) in the group without TVD versus 1,606 days (interquartile range, 826 to 3,017 days) in those with TVD. After successfully matching 83 patients, 29 of 83 (34.9%) patients in the non-TVD group had mild TR versus 28 of 83 (33.7%) patients in the TVD group (p = 0.87). 2 patients in the non-TVD group had moderate TR versus 1 patient in the TVD group at long-term follow-up. One patient in each group suffered transient atrioventricular block, but neither required pacemaker insertion., Conclusions: TVD did not compromise long-term valve durability and did not impose increased morbidity. Patients who underwent TVD had a similar prevalence of mild TR to patients without TVD. Moderate TR was exceptionally rare in both groups. When exposure is difficult, TVD is a safe and effective technical adjunct., (Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Ischemia-reperfusion injury is characterized by an increase in oxidative stress and leads to significant morbidity and death. The tyrosine kinase c-Abl is activated by oxidative stress and mediates processes that affect endothelial barrier function. We hypothesized treatment with the c-Abl inhibitor imatinib would be protective against ischemia-reperfusion injury in our ex vivo rabbit model., Methods: Heart-lung blocs were harvested from rabbits and stored in cold in Perfadex (Vitrolife, Englewood, CO) for 18 hours. Blocs were reperfused for 2 hours in an ex vivo circuit with donor rabbit blood alone (untreated group, n = 7) or donor rabbit blood and 4 mg imatinib (treatment group, n = 10). Serial clinical variables measured every 15 minutes (arterial oxygen and carbon dioxide tension and mean pulmonary artery pressures) and biochemistry of tissue samples before and after reperfusion were assessed., Results: Compared with untreated lungs, imatinib treatment improved physiologic parameters, including oxygen, carbon dioxide, and pulmonary artery pressures. Imatinib-treated lungs had less vascular barrier dysfunction as quantified by wet-to-dry weight ratios and bronchoalveolar lavage protein concentrations. Treated lungs showed less inflammation as measured by bronchoalveolar lavage myeloperoxidase assay, less mitochondrial reactive oxygen species production, and increased antioxidant catalase levels. Finally, imatinib protected lungs from DNA damage and p53 upregulation., Conclusions: Imatinib treatment significantly improved the physiologic performance of reperfused lungs and biochemical indicators associated with reperfusion injury in this ex vivo model. Further study is necessary to elucidate the mechanism of tyrosine kinase inhibition in lungs exposed to ischemia and reperfusion., (Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Prolonged hospital length of stay (PLOS) after heart transplantation increases cost and morbidity. To better inform care, we developed a risk score to identify patients at risk for PLOS after heart transplantation., Methods: We queried the United Network for Organ Sharing Scientific Registry of Transplant Recipients database for adult patients who underwent isolated heart transplantation from 2003 to 2012. The population was randomly divided into a derivation cohort (80%) and a validation cohort (20%). The outcome of interest was PLOS, defined as a posttransplant hospital length of stay of more than 30 days. Associated univariables (p < 0.20) in the derivation cohort were included in a multivariable model, and a risk index was derived from the adjusted odds ratios of significant covariates., Results: During the study period, 16,723 patients underwent heart transplantation with an average PLOS of 19 ± 21 days, and 2,020 orthotopic heart transplant recipients (12%) had PLOS. Baseline characteristics were similar between the derivation and validation cohorts. Twenty-four recipient and nine donor variables, cold ischemic time, and center volume were tested as univariables. Seventeen covariates significantly affected PLOS and comprised the prolonged hospitalization after heart transplant risk score, which was stratified into three risk groups. The risk model was subsequently validated, and predicted rates of PLOS correlated well with observed rates (R = 0.79). Rates of PLOS in the validation cohort were 8.3%, 11%, and 22% for low, moderate, and high risk groups, respectively., Conclusions: The risk of PLOS after heart transplantation can be determined at the time of transplant. The prolonged hospitalization after heart transplant score may lead to individualized postoperative management strategies to reduce duration of hospitalization for patients at high risk., (Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Debate persists over the association between blood transfusions, especially those considered discretionary, and outcomes after cardiac operations. Using data from the Maryland Cardiac Surgery Quality Initiative, we sought to determine whether outcomes differed among coronary artery bypass grafting (CABG) patients receiving 1 U of red blood cells (RBCs) vs none., Methods: We used a statewide database to review patients who underwent isolated CABG from July 1, 2011, to June 30, 2016, across 10 Maryland cardiac surgery centers. We included patients who received 1 U or fewer of RBCs from the time of the operation through discharge. Propensity scoring, using 20 variables to control for treatment effect, was performed among patients who did and did not receive a transfusion. These two groups were matched 1:1 to assess for differences in our primary outcomes: operative death, prolonged postoperative length of stay (>14 days), and a composite postoperative respiratory complication of pneumonia or reintubation, or both., Results: Of 10,877 patients who underwent CABG, 6,124 (56%) received no RBCs (group 1) during their operative hospitalization, and 981 (9.0%) received 1 U of RBCs (group 2), including 345 of 981 patients (35%) who received a transfusion intraoperatively. Propensity score matching generated 937 well-matched pairs. Compared with group 2, propensity-matched analysis revealed significantly greater 30-day survival in group 1 (99% vs 98%, p = 0.02) and reduced incidence of prolonged length of stay (3.7% vs 4.0%, p < 0.01)., Conclusions: Our collaborative statewide analysis demonstrated that even 1 unit of blood was associated with significantly worse survival and longer length of stay after CABG. Multiinstitutional quality initiatives may seek to address discretionary transfusions and possess the potential to improve patient outcomes., (Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Cardiac surgery patients colonized with Staphylococcus aureus have a greater risk of surgical site infection (SSI). The purpose of this study was to evaluate the cost-effectiveness of decolonization strategies to prevent SSIs., Methods: We compared three decolonization strategies: universal decolonization (UD), all subjects treated; targeted decolonization (TD), only S aureus carriers treated; and no decolonization (ND). Decolonization included mupirocin, chlorhexidine, and vancomycin. We implemented a decision tree comparing the costs and quality-adjusted life-years (QALYs) of these strategies on SSI over a 1-year period for subjects undergoing coronary artery bypass graft surgery from a US health sector perspective. Deterministic and probabilistic sensitivity analyses were conducted to address the uncertainty in the variables., Results: Universal decolonization was the dominant strategy because it resulted in reduced costs at near-equal QALYs compared with TD and ND. Compared with ND, UD decreased costs by $462 and increased QALYs by 0.002 per subject, whereas TD decreased costs by $205 and increased QALYs by 0.001 per subject. For 1,000 subjects, UD prevented 19 SSI and TD prevented 10 SSI compared with ND. Sensitivity analysis showed UD to be the most cost-effective strategy in more than 91% of simulations. For the 220,000 coronary artery bypass graft procedures performed yearly in the United States, UD would save $102 million whereas TD would save $45 million compared with ND., Conclusions: Universal decolonization outperforms other strategies. However, the potential costs savings of $57 million per 220,000 coronary artery bypass graft procedures comparing UD versus TD must be weighed against the potential risk of developing resistance associated with universal decolonization., (Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: In specific patients, early postoperative nutrition mitigates malnutrition-related morbidity and mortality. The goal of this study was to develop and validate a prediction score designed to stratify patients immediately after cardiac surgery according to risk for nutrition support (NS)., Methods: We identified adult cardiac surgery patients at our institution in 2012 requiring postoperative NS, enteral or parenteral. Using multivariable logistic regression modeling, we developed a Johns Hopkins Hospital Nutrition Support (JHH NS) score from relative odds ratios generated by variables that independently predicted the need for NS. The JHH NS score was then prospectively validated using all patients undergoing cardiac surgery in 2015., Results: Among 1,056 patients in the derivation cohort, 87 (8%) required postoperative NS. Seven variables were identified on multivariable analysis as independent predictors of NS need and were used to create the JHH NS score. Scores ranged from 0 to 36. Each 1-point increase in the JHH NS score was associated with a 20% increase in the risk of requiring NS (odds ratio 1.20, p < 0.001). The c-statistic of the regression model for NS was 0.85. In all, 115 of 1,336 patients (8.6%) in the validation cohort required NS. Observed rates of NS in the validation group correlated positively with predicted rates (r = 0.89)., Conclusions: The JHH NS score reliably stratified patients at risk for the need for postoperative NS. This easily calculable and highly predictive screening tool may expedite timing of initiation of NS in patients at high risk for not being able to physically take in adequate nutrition., (Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: We assessed the impact of preoperative Staphylococcus aureus screening and targeted decolonization on the incidence of postoperative methicillin-resistant S aureus (MRSA) colonization, intensive care unit MRSA transmission, and surgical site infections in cardiac surgery patients., Methods: We reviewed medical records for all adult patients during two periods: preintervention (January 2007 to April 2010) and intervention (January 2011 to December 2014). In the intervention period, we performed nasal screening for methicillin-sensitive S aureus and MRSA using polymerase chain reaction within 30 days of the operation. Colonized patients received intranasal mupirocin twice daily and chlorhexidine baths daily for 5 days; patients colonized with MRSA also received prophylactic vancomycin plus cefazolin with contact isolation precautions. Nasal surveillance for MRSA was performed on intensive care unit admission and weekly thereafter. Multivariable logistic regression models were constructed to determine risk factors for postoperative MRSA colonization, and surgical site infections and the impact of our screening program was assessed in these models. Poisson regression was used to assess MRSA transmission., Results: Comparing 2,826 preintervention and 4,038 intervention patients, cases differed in age, diabetes mellitus, preoperative infection, preoperative length of stay, and bypass time (all p ≤ 0.03). Intervention patients had risk-adjusted reductions in MRSA colonization (odds ratio 0.53, 95% confidence interval [CI]: 0.37 to 0.76, p < 0.001), transmission (incidence rate ratio 0.29, 95% CI: 0.13 to 0.65, p = 0.002), and surgical site infections (odds ratio 0.58, 95% CI: 0.40 to 0.86, p = 0.007). Increased duration of preoperative decolonization therapy was associated with decreased postoperative MRSA colonization (odds ratio 0.73, 95% CI: 0.53 to 1.00, p = 0.05)., Conclusions: Preoperative S aureus screening with targeted decolonization was associated with reduced MRSA colonization, transmission, and surgical site infections. Duration of preoperative therapy correlated with decreased frequency of postoperative MRSA colonization., (Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Previous studies have demonstrated an association between pretransplantation renal dysfunction (PRD) and increased mortality after lung transplantation (LT). The purpose of this study was to determine whether PRD impacts survival after LT in patients with cystic fibrosis (CF)., Methods: We queried the United Network for Organ Sharing (UNOS) database to identify all adult (≥18 years) recipients with CF who underwent isolated LT from May 4, 2005 to December 31, 2014. We separated recipients into those with and those without PRD (glomerular filtration rate [GFR] ≤60 mL/min). We excluded patients who required dialysis before transplantation. Kaplan-Meier analysis was used to assess unadjusted survival differences. Cox proportional hazards modeling was then performed across 26 variables to assess the risk-adjusted impact of PRD on 1-, 3-, and 5-year mortality., Results: Isolated LT was performed on 1,830 patients with CF; 17 patients were excluded because of pretransplantation dialysis. Eighty-two of 1,813 patients (4.5%) had PRD (GFR ≤60 mL/min). Kaplan-Meier analysis revealed no survival differences between PRD and non-PRD groups at 1 year (85.3% versus 89.5%; log-rank p = 0.23), 3 years (71.0% versus 72.5%; p = 0.57), or 5 years (63.3% versus 59.8%; p = 0.95). After risk adjustment, PRD was not independently associated with an increased hazard for mortality at 1 year (hazard ratio [HR], 1.38 [95% confidence interval [CI], 0.74-2.58]; p = 0.31), 3 years (HR, 1.44 [95% CI, 0.92-2.24]; p = 0.11), or 5 years (HR, 1.30 [95% CI, 0.86-1.94]; p = 0.29)., Conclusions: Although PRD has historically served as a relative contraindication to LT, our study is the first to suggest that among CF recipients, PRD was not associated with increased hazard for mortality out to 5 years after LT., (Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Dendrimer nanoparticle therapies represent promising new approaches to drug delivery, particularly in diseases associated with inflammatory injury. However, their application has not been fully explored in models of acute myocardial ischemia (MI) and reperfusion injury., Methods: White male New Zealand rabbits underwent left thoracotomy with 30-minute temporary left anterior descending artery occlusion and MI confirmed by electrocardiography and histology (MI rabbits, n = 9), or left thoracotomy and pericardial opening for 30 minutes but no left anterior descending artery occlusion (control [C] rabbits, n = 9) rabbits. Following the 30-minute period, a dendrimer (generation 6 dendrimer conjugated to cyanine-5 fluorescent dye [G6-Cy5], 6.7 nm diameter) was administered intravenously and the chest closed in layers. Animals were sacrificed at 3 hours (3 MI, 3 C), 24 hours (3 MI, 3 C), or 48 hours (3 MI, 3 C) postsurgery., Results: As compared to controls, MI rabbits had twofold G6-Cy5 uptake in the myocardial anterior wall as compared to the same region in nonischemic control rabbits at 24 hours postsurgery (6.01 ± 0.57 μg/g versus 2.85 ± 0.85 μg/g; p = 0.04). This trend was also present at 48 hours (6.38 ± 1.53 μg/g versus 3.95 ± 0.60 μg/g, p = 0.21) and was qualitatively evident on confocal microscopy. G6-Cy5 half-life in serum was approximately 12 hours, with 22% of the injected G6-Cy5 dose remaining at 48 hours., Conclusions: This study demonstrates for the first time that dendrimer nanodevices selectively localize in ischemic as compared to healthy myocardium. This indicates that dendrimer nanodevices are promising agents to deliver drugs specifically to the ischemic myocardium to attenuate the injury. Subsequent studies will assess the efficacy of a dendrimer-drug conjugate in ameliorating reperfusion injury following MI., (Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: The Society of Thoracic Surgeons (STS) database does not distinguish between a decline in creatinine clearance vs new hemodialysis (HD) when qualifying acute renal failure (ARF) after a cardiac operation. We hypothesized that patients requiring HD experience significantly greater postoperative morbidity and death., Methods: We included all patients who underwent STS index cardiac operations at our institution from 2008 to March 2015 and did not have preexisting renal failure (creatinine >4.0 mg/dL or preoperative HD). We identified patients meeting STS criteria for ARF: threefold rise in serum creatinine, creatinine exceeding 4.0 mg/dL (non-HD ARF) with minimum rise of 0.5 mg/dL, or HD (ARF-HD). After propensity matching non-HD ARF and ARF-HD groups across 14 variables (including baseline glomerular filtration rate), we compared incidences of our primary outcome, death, and secondary outcomes, intensive care unit (ICU) and hospital length of stay (LOS), and discharge to a location other than home., Results: Among 4,154 study patients, we identified 113 (2.7%) that experienced new-onset non-HD ARF (n = 57) or ARF-HD (n = 56) postoperatively. Propensity matching resulted in 51 well-matched pairs who experienced non-HD ARF or ARF-HD (all p > 0.10). Patients requiring HD suffered significantly greater operative mortality (67% vs 22%, p < 0.01), longer ICU LOS (326 vs 176 hours, p < 0.01), and greater postoperative hospital LOS (34 vs 17 days, p < 0.01). ARF-HD patients also demonstrated a trend toward higher rates of discharge to a location other than home (71% vs 45%, p = 0.08)., Conclusions: After cardiac operations, patients who experienced ARF-HD experienced triple the mortality and double the ICU and postoperative hospital LOS compared with patients who experienced non-HD ARF., (Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Concerns over prolonged allograft ischemia have limited the widespread adoption of long-distance organ procurement in heart transplantation (HT). We sought to assess whether donor distance from the center of transplantation independently affects mortality., Methods: We queried the United Network for Organ Sharing (UNOS) database for adults undergoing isolated HT from 2005 to 2012. Risk-adjusted Cox proportional hazards models were constructed for the primary outcomes of 30-day and 1-year mortality, and the independent impact of donor distance from transplantation center at the time of procurement was assessed., Results: We included 14,588 heart transplant recipients. The mean distance from location of the donor heart to transplantation center was 184.4 ± 214.6 miles; 1,214 HTs (8.3%) occurred at the same location as the donor heart. Ischemic times were inversely related to the distance from the site of donor procurement to recipient transplantation. After risk adjustment, longer donor distances (in miles) were associated with a significantly lower risk of mortality at both 30 days (hazard ratio [HR] 0.9993, 95% confidence interval [CI]: 0.9988 to 0.9998, p < 0.01) and 1 year (HR 0.9994, 95% CI: 0.9989 to 0.9999, p = 0.015). Risk-adjusted hazards for mortality were significantly reduced in recipients receiving hearts from more than 25 miles away. The hazard reduction was greatest in recipients receiving donor hearts from more than 500 miles away (1-year HR 0.64, p < 0.01; 30-day HR 0.47, p < 0.01)., Conclusions: Longer distances between donor location and center of heart transplantation are associated with a reduced hazard for survival at 30 days and 1 year, despite greater ischemic times. Future studies are necessary to elucidate the protective factors surrounding long-distance heart donation., (Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Since the introduction of the Lung Allocation Score (LAS), the mean LAS has risen. Still, it remains uncertain whether mortality has improved in the most severely ill lung transplant recipients over this time period., Methods: Using the United Network for Organ Sharing database, we identified 3,548 adult lung transplant recipients from May 4, 2005, to March 31, 2014, with a match-time LAS in the upper quartile (>75th%ile). We divided this population across three eras: 1 = May 4, 2005, to December 31, 2008 (n = 1,280); 2 = January 1, 2009, to December 31, 2011 (n = 1,266); and 3 = January 1, 2012, to March 31, 2014 (n = 1,002). Cox proportional hazards models were constructed for the primary outcomes of 30-day and 1-year mortality to assess the independent impact of the era of transplantation., Results: The mean LAS at time of transplant for patients in the upper quartile in eras 1, 2, and 3 was 63, 73, and 79, respectively (p < 0.001). Later eras of transplantation benefited from a significant improvement in survival at 1 year (log-rank p = 0.001) but not at 30 days (log-rank p = 0.152). After risk adjustment, lung transplantation in more recent eras was associated with improved mortality at both 30 days (era 3 hazard ratio [HR] = 0.50, 95% confidence interval [CI] 0.32% to 0.78%, p = 0.002) and 1 year (era 2 HR = 0.77, 95% CI 0.64% to 0.94%, p = 0.008; era 3 HR = 0.54, 95% CI 0.43% to 0.68%, p < 0.001)., Conclusions: Despite a progressively rising LAS, survival is improving among recipients with the highest LAS at the time of lung transplantation. This calls into question the notion of a maximum LAS beyond which lung transplantation becomes futile, a so-called LAS ceiling., (Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Our objective was to determine whether the choice of a HeartWare HVAD as opposed to a Heartmate II left ventricular assist device (HMII LVAD), impacts survival after heart transplantation after controlling for patient, donor, and center characteristics., Methods: We queried the United Network for Organ Sharing (UNOS) database, which has recently made pretransplantation device duration available, for all adult patients undergoing bridge to transplantation (BTT) between January 2011 and March 2016. Recipient, donor, and transplant-specific characteristics were compared between patients receiving either device. Unadjusted survival was estimated with the Kaplan-Meier method. Risk-adjusted Cox proportional hazard models were constructed to determine the independent impact of device selection on mortality., Results: Three thousand three hundred fifty-six patients who received the HMII and 1,051 patients who received the HVAD met inclusion criteria. Patients who received the HMII had a longer mean duration of VAD support (HMII, 429 days versus HVAD, 314 days; p < 0.001) but spent shorter periods on the waiting list (median, 190 days versus 232 days; p < 0.001). Patients who received the HMII had worse pre-LVAD renal function than did those who received the HVAD (glomerular filtration rate [GFR], 57 mL/min versus 62 mL/min, respectively; p = 0.001), but there was no difference in postoperative new-onset dialysis after transplantation (11.6% versus 10.5%, respectively; p = 0.14). There was no difference in unadjusted posttransplantation 30-day (95.5% versus 96.7%, respectively; log-rank p = 0.09), 6-month (91.8% versus 92.6%, respectively; p = 0.35), or 1-year (89.7% versus 90.9%, respectively; p = 0.22) survival between the 2 groups. After risk adjustment with Cox modeling, device selection did not predict mortality at any time point., Conclusions: Among patients who received a BTT LVAD and then received a heart transplant, no survival differences were seen between patients initially implanted with an HVAD versus an HMII., (Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Mediastinal reexplorations for bleeding are associated with significant morbidity and mortality. This study hypothesized that bleeding patients who undergo delayed chest closure after an initial operation experience similar outcomes in comparison with patients who have initial chest closure and later require an unplanned reexploration., Methods: This study included all patients in the Johns Hopkins University School of Medicine (Baltimore, MD) institutional Society of Thoracic Surgeons (STS) database who underwent cardiac surgical procedures or thoracic transplantation from 2011 to June 2014, had an intraoperative red blood cell transfusion requirement of 2 units or more, and required mediastinal reexploration for bleeding. Reexplorations were classified as planned (temporary chest closure for a planned "second look") or unplanned (initial sternal closure and subsequent reexploration). The two groups were then propensity matched. The primary outcome was 30-day mortality. Secondary outcomes were major complication rates, hospital length of stay, duration of mechanical ventilation, and incidence of postoperative pneumonia and cardiac arrest., Results: Among 3,293 patients, 110 (3.3%) met inclusion criteria and required mediastinal reexploration for bleeding. This group included 62 planned (56%) and 48 unplanned (44%) reexplorations. After propensity matching 30 pairs of patients across 16 variables, operative mortality rates were comparable (37% vs 37%; p = 1.00) between unplanned and planned reexploration cohorts. There were no differences in rates of deep sternal wound infection, renal failure, postoperative hospital length of stay, pneumonia, or cardiac arrest, with the exception of a higher rate of prolonged intubation (93% vs 53%; p < 0.01) in the planned reexploration group., Conclusions: Delayed sternal closure is a safe alternative to initial definitive chest closure when concern exists for postoperative bleeding., (Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

We simulated the impact of regionalization of isolated heart and lung transplantation within United Network for Organ Sharing (UNOS) regions. Overall, 12 594 orthotopic heart transplantation (OHT) patients across 135 centers and 12 300 orthotopic lung transplantation (OLT) patients across 67 centers were included in the study. An algorithm was constructed that "closed" the lowest volume center in a region and referred its patients to the highest volume center. In the unadjusted analysis, referred patients were assigned the highest volume center's 1-year mortality rate, and the difference in deaths per region before and after closure was computed. An adjusted analysis was performed using multivariable logistic regression using recipient and donor variables. The primary outcome was the potential number of lives saved at 1 year after transplant. In adjusted OHT analysis, 10 lives were saved (95% confidence interval [CI] 9-11) after one center closure and 240 lives were saved (95% CI 209-272) after up to five center closures per region, with the latter resulting in 1624 total patient referrals (13.2% of OHT patients). For OLT, lives saved ranged from 29 (95% CI 26-32) after one center closure per region to 240 (95% CI 224-256) after up to five regional closures, but the latter resulted in 2999 referrals (24.4% of OLT patients). Increased referral distances would severely limit access to care for rural and resource-limited populations., (© Copyright 2016 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Background: Postoperative complications are associated with increased morbidity and mortality after cardiac operations. We sought to quantify the effect of multiple complications on noninstitutionalized recovery after cardiac operations., Methods: We identified 2,477 adult patients from our institutional cardiac surgery database who underwent one of seven index cardiac surgical operations from 2011 to 2014. We calculated failure-to-rescue rates for all individual complications and combinations of complications. We used multivariable logistic regression to determine the effect of the interaction of postoperative complications on our primary outcome of operative death and secondary outcomes of prolonged hospital length of stay and discharge to a location other than home., Results: From 2011 to 2014, at least one complication occurred in 366 patients (14.8%), and multiple complications occurred in 102 (4.1%), including three complications in 20 (0.8%). Operative mortality occurred in 41% of patients with multiple complications vs in 4.9% of those with an isolated complication and in 0.7% of those without complications. Significant interactions that negatively affected survival were noted between nearly every combination of complications. The occurrence of renal failure and unplanned reoperation together were associated with increased deaths (odds ratio, 108.4; 95% confidence interval, 13.5 to 869.9; p < 0.001). Median hospital length of stay and discharge rates to a location other than home correlated positively with the number of postoperative complications., Conclusions: Major complications after cardiac operations are associated with an increased risk for operative death, longer hospital length of stay, and higher rates of discharge to a location other than home. These adverse outcomes are magnified when multiple complications are encountered., (Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Risk factors for non-skin cancer de novo malignancy (DNM) after lung transplantation have yet to be identified. We queried the United Network for Organ Sharing database for all adult lung transplant patients between 1989 and 2012. Standardized incidence ratios (SIRs) were computed by comparing the data to Surveillance, Epidemiology, and End Results Program data after excluding skin squamous/basal cell carcinomas. We identified 18 093 adult lung transplant patients; median follow-up time was 1086 days (interquartile range 436-2070). DNMs occurred in 1306 patients, with incidences of 1.4%, 4.6%, and 7.9% at 1, 3, and 5 years, respectively. The overall cancer incidence was elevated compared with that of the general US population (SIR 3.26, 95% confidence interval [CI]: 2.95-3.60). The most common cancer types were lung cancer (26.2% of all malignancies, SIR 6.49, 95% CI: 5.04-8.45) and lymphoproliferative disease (20.0%, SIR 14.14, 95% CI: 9.45-22.04). Predictors of DNM following lung transplantation were age (hazard ratio [HR] 1.03, 95% CI: 1.02-1.05, p < 0.001), male gender (HR 1.20, 95% CI: 1.02-1.42, p = 0.03), disease etiology (not cystic fibrosis, idiopathic pulmonary fibrosis or interstitial lung disease, HR 0.59, 95% CI 0.37-0.97, p = 0.04) and single-lung transplantation (HR 1.64, 95% CI: 1.34-2.01, p < 0.001). Significant interactions between donor or recipient smoking and single-lung transplantation were noted. On multivariable survival analysis, DNMs were associated with an increased risk of mortality (HR 1.44, 95% CI: 1.10-1.88, p = 0.009)., (© Copyright 2016 The American Society of Transplantation and the American Society of Transplant Surgeons.)

Background: The purpose of this study was to develop and validate a risk score for readmissions after cardiac operations., Methods: Adults surviving to discharge after cardiac operations at a single institution from 2008 to 2013 were randomly divided 3:1 into training and validation cohorts. The primary outcome was readmission within 30 days of discharge. A multivariable model was constructed in the training cohort incorporating variables associated with 30-day readmission in univariate logistic regression. Points were assigned to predictors in the multivariable model proportional to their odds ratios., Results: Among 5,193 patients undergoing cardiac operations and surviving to discharge, the 30-day readmission rate was 10.3% (n = 537). The most common reasons for readmission were volume overload (24%; n = 131) and infection (21%; n = 113). The risk score incorporated 5 multivariable predictors and was out of 20 possible points. The predicted rate of 30-day readmission based on the training cohort ranged from 5.9% (score = 0) to 54.7% (score = 20). Patients were categorized as low (score = 0; readmission 5.7%), moderate (score 1-7; readmission 11.0%), and high risk (score >7; readmission 24.2%) (p < 0.001). Thirty-day readmission rates based on these score categories were similar in the validation cohort (low 6.4%, moderate 11.0%, high 17.4%; p < 0.001). There was a robust correlation between predicted rates of readmission in the training cohort based on the composite risk score and actual rates of readmission in the validation cohort (r = 0.95; p < 0.001)., Conclusions: We developed and validated a risk score for readmission after cardiac operations that may have utility in targeting interventions and modifying risk factors in high-risk populations., (Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Variation in red blood cell (RBC) transfusion practices exists at cardiac surgery centers across the nation. We tested the hypothesis that significant variation in RBC transfusion practices between centers in our state's cardiac surgery quality collaborative remains even after risk adjustment., Methods: Using a multiinstitutional statewide database created by the Maryland Cardiac Surgery Quality Initiative (MCSQI), we included patient-level data from 8,141 patients undergoing isolated coronary artery bypass (CAB) or aortic valve replacement at 1 of 10 centers. Risk-adjusted multivariable logistic regression models were constructed to predict the need for any intraoperative RBC transfusion, as well as for any postoperative RBC transfusion, with anonymized center number included as a factor variable., Results: Unadjusted intraoperative RBC transfusion probabilities at the 10 centers ranged from 13% to 60%; postoperative RBC transfusion probabilities ranged from 16% to 41%. After risk adjustment with demographic, comorbidity, and operative data, significant intercenter variability was documented (intraoperative probability range, 4% -59%; postoperative probability range, 13%-39%). When stratifying patients by preoperative hematocrit quartiles, significant variability in intraoperative transfusion probability was seen among all quartiles (lowest quartile: mean hematocrit value, 30.5% ± 4.1%, probability range, 17%-89%; highest quartile: mean hematocrit value, 44.8% ± 2.5%; probability range, 1%-35%)., Conclusions: Significant variation in intercenter RBC transfusion practices exists for both intraoperative and postoperative transfusions, even after risk adjustment, among our state's centers. Variability in intraoperative RBC transfusion persisted across quartiles of preoperative hematocrit values., (Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: The aim of this study was to determine whether the duration of left ventricular device support (LVAD) influenced outcomes after orthotopic heart transplantation in a modern, bridge to transplant national cohort., Methods: The United Network for Organ Sharing database, which has recently made pretransplant LVAD duration available, was queried for all adult bridge to transplant patients between January 2011 and December 2012. Three LVAD duration cohorts were generated, as follows: short (less than 90 days), intermediate (90 to 365 days), and prolonged (more than 365 days). Recipient, donor, and transplant-specific characteristics were compared among the duration cohorts. Unadjusted short-term and long-term survivals were estimated with the Kaplan-Meier method. Risk-adjusted models were also constructed to determine the independent impact of device duration on mortality., Results: Of the 1,332 patients who met criteria for inclusion, 9.8% (n = 130), 54.7% (n = 729), and 35.5% (n = 473) were classified as short, intermediate, and prolonged, respectively. Although the performance status across each cohort was similar at listing (p = 0.38), more patients in the intermediate and prolonged cohorts were considered functionally independent before orthotopic heart transplantation (32% and 37%, respectively, versus 18%; p < 0.001). Additionally, despite worse baseline renal function in the intermediate and prolonged cohorts relative to the short cohort (glomerular filtration rate, 57 and 57 versus 69, p < 0.001), there was no difference in the incidence of new onset posttransplant renal failure (7% versus 10%, 9%, p = 0.41). There was also no difference in 30-day survival (98%, 96%, 95%, p = 0.51), 6-month survival (93%, 92%, 92%, p = 0.93), or 1-year survival (91%, 89%, 89%, p = 0.78) across the cohorts. After risk adjustment, duration did not independently predict mortality at any timepoint., Conclusions: In the largest, non-industry sponsored study of a modern bridge to transplant cohort, we demonstrated that duration of LVAD support before orthotopic heart transplantation does not influence posttransplant morbidity or mortality. In subanalysis, support for 90 days or more is associated with improvements in pretransplant functional performance., (Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Neurocognitive dysfunction and injury remain problematic after cardiac procedures requiring hypothermic circulatory arrest (HCA). Due to poor blood-brain barrier penetrance and toxicities associated with systemic drug therapies, clinical success has been elusive. Accordingly, we explored targeted dendrimer (a nanoparticle) drug therapies in our well-established canine model of HCA to characterize the biodistribution and cellular localization of these nanoparticles in areas of known neuronal apoptosis and necrosis., Methods: Class A, 27- to 30-kg male hounds were administered an initial intravenous bolus (10% of the total dose [200 mg]) of generation-six polyamidoamine dendrimer (6.7 nm) labeled with cyanine 5, and cardiopulmonary bypass with peripheral cannulation was initiated. After 90 minutes of HCA, 70% of the total dose was infused over a 6-hour period. The final 20% of the total dose was given 24 hours post-HCA. The brain was harvested 48 hours later (72 hours post-HCA) and analyzed for dendrimer 6-cyanine 5 biodistribution., Results: The dorsal hippocampus demonstrated the highest brain accumulation of dendrimer 6-cyanine 5, which closely corresponds to the distribution of apoptotic neurons evident with histologic staining and on confocal imaging. In injured brain regions, dendrimer traversed the blood-brain barrier and localized within the target cells (injured neurons and microglia)., Conclusions: These findings have exciting implications for the future development of novel therapeutics to mitigate neurocognitive deficits in this group of patients., (Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Biventricular support before orthotopic heart transplantation (OHT) has been shown to adversely affect short- and long-term outcomes, but the comparative effect of support type is largely unknown. This study determined the comparative effect of univentricular and biventricular support on survival in bridged patients after OHT., Methods: The United Network of Organ Sharing database was queried for adult patients bridged to OHT with a univentricular (left ventricular assist device [LVAD]), biventricular (biventricular assist device [BiVAD]), or total artificial heart ([TAH]) device between 2004 and 2012. Unconditional and conditional survivals were compared with the Kaplan-Meier method. Cox proportional hazards regression models were constructed to determine the risk-adjusted influence of support type on death., Results: Of the 4,177 patients identified, 3,457 (20.4%), 575 (3.4%), and 145 (0.9%) were bridged with an LVAD, BiVAD, and TAH, respectively. Unadjusted 30-day, 1-year, and 5-year estimated survival was greater in LVAD patients than in the BiVAD and TAH cohorts. After risk-adjustment, BiVAD and TAH were associated with an increased risk of death at all time points. Unadjusted and adjusted 5-year survival, conditional on 1-year survival, was worse, however, in only TAH patients., Conclusions: Patients with biventricular failure bridged to OHT with a TAH or BiVAD experience worse short- and long-term survival comparison with those with an LVAD. This difference is most likely due to an increase in early death and depends on the type of BiVAD device implanted., (Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Objectives: The aim of this study was to develop a risk index specific to patients on mechanical circulatory support that accurately predicts 1-year mortality after orthotopic heart transplantation using the United Network for Organ Sharing database., Background: Few clinical tools are available to aid in the decision between continuing long-term device support and performing transplantation in patients bridging with mechanical circulatory support., Methods: Using a prospectively collected, open cohort, 6,036 patients receiving mechanical circulatory support who underwent orthotopic heart transplantation between 2000 and 2013 were evaluated and randomly separated into derivation (80%) and validation (20%) groups. Multivariate logistic regression models were constructed using variables that improved the explanatory power of the model, which was determined using multiple methods. Points for a simple additive risk index were apportioned on the basis of relative effect on odds of 1-year mortality., Results: A 75-point scoring system was created from 9 recipient and 4 donor variables. The average score in the validation cohort was 14.4 ± 7.7, and scores ranged from 0 to 57; these values were similar to those in the derivation cohort. Each 1-point increase predicted an 8.3% increase in the odds of 1-year mortality (odds ratio: 1.08; 95% confidence interval: 1.06 to 1.11). Low (0 to 10), intermediate (11 to 20), and high (>20) risk score cohorts were created, with predicted average 1-year mortalities of 8.6%, 12.8%, and 31%, respectively, in the validation cohort., Conclusions: The investigators present a novel, internally cross-validated risk index that accurately predicts mortality in bridge-to-transplantation patients., (Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Background: We sought to determine the ability of the Model for End-Stage Liver Disease eXcluding INR (MELD-XI) to predict short-term and long-term outcomes in pediatric patients undergoing orthotopic heart transplant., Methods: The United Network for Organ Sharing Database was queried for all pediatric patients (aged 1 to 18 years) undergoing orthotopic heart transplant from 2000 to 2012. The logarithmic relationship between the serum creatinine and bilirubin was used to calculate the MELD-XI score. Lowess smoothing plots were referenced, and a score threshold of 12.2 was used to stratify patients into low (75%) and high (25%) MELD-XI cohorts. Patient-specific characteristics, intraoperative variables, and postoperative outcomes were compared between the two cohorts. Differences in survival at 30 days, 1 year, and 5 years between the MELD-XI cohorts were estimated by the Kaplan-Meier method. Cox proportional hazards modeling was used to determine the risk-adjusted effect of a high MELD-XI score on death., Results: After patients with missing MELD-XI scores were excluded, 2,939 patients met the inclusion criteria. Unconditional 30-day (93.1% vs 98.0%, p < 0.001), 1-year (85.9% vs 92.9%, p < 0.001), and 5-year (71.2% vs 79.5%, p < 0.001) survivals were significantly worse in the high-score cohort. However, 1-year survival excluding 90-day deaths (94.9% vs 95.8%, p = 0.29) and 5-year survival excluding 1-year deaths (82.8% vs 85.6%, p = 0.09) were statistically equivalent. When modeled as a categoric variable, a high MELD-XI score was an independent predictor of death at 30 days (hazard ratio, 2.86; 95% confidence interval, 1.84 to 4.45; p < 0.001), 1 year (hazard ratio, 1.88; 95% confidence interval, 1.42 to 2.48, p < 0.001), and 5 years (hazard ratio, 1.41; 95% confidence interval, 1.19 to 1.77; p < 0.001). For every 1-point increase in the MELD-XI score, mortality increased 11% at 30 days, 7% at 1 year, and 4% at 5 years (p < 0.001). The MELD-XI was not predictive of conditional mortality at 1 year or 5 years., Conclusions: The MELD-XI scoring system can be used in pediatric orthotopic heart transplant to identify patients at risk for poor outcomes. Because long-term survival is largely driven by early death, renal insufficiency and congestive hepatopathy should be optimized before transplant., (Copyright © 2016 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Acute kidney injury (AKI) continues to complicate cardiac operations. We sought to determine whether nadir oxygen delivery (DO2) on cardiopulmonary bypass (CPB) was a risk factor for AKI while also accounting for other postoperative factors., Methods: Using propensity scoring, we matched 85 patients who developed AKI after cardiac operations on CPB with 85 control patients who did not. We analyzed the following variables through midnight on postoperative day 1 (POD1): DO2, antibiotics, blood products and vasopressors (intraoperatively and postoperatively), and hemodynamic variables., Results: Univariable analysis revealed AKI patients had lower nadir DO2 on CPB (208 vs 230 mL O2/min/m(2) body surface area, p = 0.03), lower intensive care unit admission blood pressure gradient across the kidney (mean arterial pressure minus central venous pressure; 60 vs 68 mm Hg; p < 0.001), a greater proportion of patients with mean arterial pressure of less than 60 mm Hg for more than 15 minutes in the postoperative period (70% vs 42%, p < 0.001), a greater chance of having a cardiac index of less than 2.2 (74% vs 49%, p = 0.02), and greater total vasopressor use through the end of POD1 (5.2 vs 2.3 mg, p = 0.002). On multivariable analysis, predictors of AKI were a DO2 on CPB of less than 225 mL O2/min/m(2) (odds ratio, 2.46; 95% confidence interval, 1.21 to 5.03; p = 0.01) and postoperative mean arterial pressure of less than 60 mm Hg for more than 15 minutes (odds ratio, 3.96; 95% confidence interval, 1.92 to 8.20; p < 0.001). An average postoperative pressor dose greater than 0.03 μg/kg/min did not reach significance (odds ratio, 1.98; 95% confidence interval, 0.95 to 4.11; p = 0.07)., Conclusions: Postoperative hypotension on POD0 or POD1 and low DO2 on CPB both independently increase the AKI risk in cardiac surgical patients., (Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: The aim of this study was to determine the utility of the Model for End-Stage Liver Disease Excluding INR (MELD-XI) in predicting early outcomes (30 days and 1 year) and late outcomes (5 years) in patients after orthotopic heart transplantation (OHT)., Methods: The United Network for Organ Sharing database was queried for all adult patients (aged ≥ 18 years) undergoing OHT from 2000 to 2012. A MELD-XI was calculated and the population stratified into score quartiles. Early and late survivals were compared among the MELD-XI cohorts. Multivariable Cox proportional hazards models were constructed to determine the capacity of MELD-XI (when modeled both as a categoric and a continuous variable) to predict 30-day, 1-year, and 5-year mortality. Conditional models were also designed to determine the effect of early mortality on long-term survival., Results: A total of 22,597 patients were included for analysis. The MELD-XI cutoff scores were established as follows: low (≤ 10.5), low-intermediate (10.6 to 12.6), intermediate-high (12.7 to 16.4), and high (>16.4). The high MELD-XI cohort experienced statistically worse 30-day, 1-year, and 5-year unconditional survivals when compared with patients with low scores (p < 0.001). Similarly, a high MELD-XI score was also predictive of early and late mortality (p < 0.001) after risk adjustment. There was, however, no difference in 5-year survival between the high score and low score cohorts after accounting for 1-year deaths. Subanalysis of patients bridged to transplant with a continuous-flow left ventricular assist device demonstrated similar findings., Conclusions: This is the first known study to examine the relationship between a high MELD-XI score and outcomes in patients after OHT. Patients with hepatic or renal dysfunction before OHT should be closely monitored and aggressively optimized as early mortality appears to drive long-term outcomes., (Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: In this study we sought to construct a novel scoring system to pre-operatively stratify a patient's risk of 1-year mortality after lung transplantation (LTx) based on recipient- and donor-specific characteristics., Methods: The UNOS database was queried for adult (≥18 years) patients undergoing LTx between May 1, 2005 and December 31, 2012. The population was randomly divided in a 4:1 fashion into derivation and validation cohorts. A multivariable logistic regression model for 1-year mortality was constructed within the derivation cohort. Points were then assigned to independent predictors (p < 0.05) based on relative odds ratios. Risk groups were established based on score ranges., Results: During the study period, 9,185 patients underwent LTx and the 1-year mortality was 18.0% (n = 1,654). There was a similar distribution of variables between the derivation (n = 7,336) and validation (n = 1,849) cohorts. Of the 14 covariates included in the final model, 9 were ultimately allotted point values (maximum score = 70). The model exhibited good predictive strength (c = 0.65) in the derivation cohort and demonstrated a strong correlation between the observed and expected rates of 1-year mortality in the validation cohort (r = 0.87). The low-risk (score 0 to 11), intermediate-risk (score 12 to 21) and high-risk (score ≥22) groups had a 10.8%, 17.1% and 32.0% risk of mortality (p < 0.001), respectively., Conclusions: This is the first scoring system that incorporates both recipient- and donor-related factors to predict 1-year mortality after LTx. Its use could assist providers in the identification of patients at highest risk for poor post-transplant outcomes., (Copyright © 2015 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.)

Background: This study evaluated the potential association of institutional volume with survival and mortality subsequent to major complications in a modern cohort of pediatric patients after orthotopic heart transplantation (OHT)., Methods: The United Network of Organ Sharing database was queried for pediatric patients (aged ≤18 years) undergoing OHT between 2000 and 2010. Institutional volume was defined as the average number of transplants completed annually during each institution's active period and was evaluated as categoric and as a continuous variable. Logistic regression models were used to determine the effect of institutional volumes on postoperative outcomes, which included renal failure, stroke, rejection, reoperation, infection, and a composite complication outcome. Cox modeling was used to analyze the risk-adjusted effect of institutional volume on 30-day, 1-year, and 5-year mortality. Kaplan-Meier estimates were used to compare differences in unconditional survival., Results: A total of 3,562 patients (111 institutions) were included and stratified into low-volume (<6.5 transplants/year, 91 institutions), intermediate-volume (6.5 to 12.5 transplants/year, 12 institutions), and high-volume (>12.5 transplants/year, 8 institutions) tertiles. Unadjusted survival was significantly different at 30 days (p = 0.0087) in the low-volume tertile (94.2%; 95% confidence interval, 92.7% to 95.4%) compared with the high-volume tertile (96.8%; 95% confidence interval, 95.7% to 97.7%). No difference was observed at 1 or 5 years. Risk-adjusted Cox modeling demonstrated that low-volume institutions had an increased rate of mortality at 30 days (hazard ratio, 1.91; 95% confidence interval, 1.02 to 3.59; p = 0.044), but not at 1 or 5 years. High-volume institutions had lower incidences of postoperative complications than low-volume institutions (30.3% vs 38.4%, p < 0.001). Despite this difference in the rate of complications, survival in patients with a postoperative complication was similar across the volume tertiles., Conclusions: No association was observed between institutional volume and adjusted or unadjusted long-term survival. High-volume institutions have a significantly lower rate of postoperative complications after pediatric OHT. This association does not correlate with increased subsequent mortality in low-volume institutions. Given these findings, strategies integral to the allocation of allografts in adult transplantation, such as regionalization of care, may not be as relevant to pediatric OHT., (Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Although the exact cause of dysphagia after cardiac operations is unknown, timely diagnosis is critical to avoid a devastating aspiration event. Accordingly, we sought to generate the risk of dysphagia in cardiac surgery (RODICS) score to identify patients at risk for its development after heart surgery., Methods: All adult heart surgery patients at our institution between January 2011 and March 2012 were analyzed. A videofluoroscopic swallow study stratified patients into two groups based on the presence or absence of dysphagia. Covariates (p < 0.20) were included in a multivariable model to determine the strongest independent predictors of postoperative dysphagia. Based on the relative odds ratios of significant variables, the RODICS score was generated. Risk cohorts were then created based on easily applicable, whole-integer score cutoffs., Results: During the study period, 115 of 1,314 patients (8.8%) undergoing heart surgery were diagnosed with clinically significant dysphagia. The 38-point RODICS score comprises seven patient-specific characteristics and perioperative factors. The low risk (less than 4), intermediate risk (5 to 9), and high risk (more than 9) cohorts had postoperative dysphagia rates of 3.0%, 6.8%, and 21.6%, respectively (p < 0.001). The intermediate-risk cohort (odds ratio 2.3, 95% confidence interval: 1.33 to 4.27, p = 0.01) and high-risk cohort (odds ratio 8.9, 95% confidence interval: 5.22 to 15.32, p < 0.001) were at significantly higher risk of dysphagia developing. The RODICS score demonstrated excellent discriminatory ability (area under the curve 0.75)., Conclusions: The incidence and impact of dysphagia after open cardiac operations is significant. This novel scoring system could lead to prompt identification of patients at high risk for postoperative dysphagia and potentially minimize the complications of aspiration., (Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)