Relationship of intraoperative perfusion parameters to the need for immediate extracorporeal support following heart transplantation.

PURPOSE: We sought to assess the relationship of intraoperative perfusion parameters while on cardiopulmonary bypass, including oxygen delivery (DO2), to the need for ECMO following orthotopic heart transplantation (OHT). METHODS: We included all adult (>18 years old) OHTs performed at our institution since implementation of an electronic perfusion record (March 2019-February 2020). Multi-organ transplants were excluded. The primary outcome was the need for immediate venoarterial ECMO in the OR following OHT. Univariable statistics were computed across demographic, clinical, operative, and perfusion variables, including oxygen delivery (DO2) measured each minute. RESULTS: Fifty-three OHT were included with a median age of 54 years (interquartile range, 45-61). The primary outcome occurred in eight patients (15.1%). A significantly greater proportion of patients requiring ECMO had ischemic cardiomyopathy (50.0% (4/8) vs. 15.6% (7/45), p = 0.02) and had preoperative ventricular assist devices (37.5% (3/8) vs. 8.9% (4/45), p = 0.03). Median bypass times were longer in the ECMO group (217 vs. 147 minutes, p = 0.001). Phenylephrine doses were nonsignificantly higher in ECMO patients (4.1 vs. 1.9 mg, p = 0.10). No significant differences were observed in single-point median DO2 (275 vs. 294 mL O2/min/m2 BSA, p = 0.17) and nadir DO2 (226 vs. 222, p = 0.94), but increasing time and depth of DO2 below a threshold of 300 mL O2/min/m2 BSA (i.e. area over the DO2 curve (AOC) but below threshold) was significantly associated with the need for postoperative ECMO (p = 0.04). CONCLUSION: This is the first study to examine the relationship of perfusion parameters, including oxygen delivery, to outcomes following heart transplantation. We note that DO2 < 300-AOC was significantly associated with the need for postoperative ECMO following heart transplant. Further study will clarify whether potential DO2 differences in patients who require post-OHT ECMO reflect vasoplegia, or a more causative relationship which might be leveraged to improve outcomes.

Five-Year Mortality Hazard Is Reduced In Chronic Obstructive Pulmonary Disease Patients Receiving Double- versus Single-Lung Transplants.

BACKGROUND: Previous studies suggest double-lung transplant (DLT) may be associated with superior survival compared to single-lung transplantation (SLT) in chronic obstructive pulmonary disease (COPD) recipients. The purpose of this study was to compare survival in patients with COPD undergoing DLT versus SLT since the inception of the lung allocation score. METHODS: We used the United Network for Organ Sharing database to retrospectively identify adult patients with COPD who underwent isolated lung transplantation from 5/4/2005-12/31/2014. We then separated patients into DLT versus SLT. Short-term (1 y) and long-term survival (5 y) were compared between DLT and SLT cohorts by the method of Kaplan-Meier, and Cox proportional hazards modeling was used to adjust for case mix. RESULTS: Four thousand eight hundred thirty-two COPD patients were listed, and 3554 underwent lung transplantation over the study period, including 1358 SLTs (38%) and 2196 DLTs (62%). Survival 1 y after listing was 93% for those remaining wait listed (n = 1892) versus 91% for SLT (n = 1093) versus 89% for DLT (n = 1847) (log-rank P < 0.01). Survival at 1 y after transplant was 88% for both SLT and DLT groups (log-rank P = 0.93); however, 5-y survival was significantly lower after SLT (51% versus 59%, log-rank P < 0.01). After risk adjustment, hazard for 1-y mortality after DLT was not significantly reduced compared to SLT (hazard ratio 0.89 [0.69-1.14], P = 0.36) but was significantly reduced 5 y after DLT (hazard ratio 0.88 [0.78-0.99], P = 0.04). CONCLUSIONS: In the largest survival analysis of COPD recipients since the inception of the lung allocation score, the hazard for 5-y mortality was significantly reduced in recipients who underwent DLT as compared to SLT.

Outcomes after heart transplantation in sensitized patients bridged with ventricular assist devices.

OBJECTIVE: Sensitization has been associated with worse outcomes following heart transplantation (HTx). The use of ventricular assist devices (VAD) is a risk factor for the development of sensitization. We investigated the impact of left ventricular assist devices (LVAD) and sensitization in HTx recipients. METHODS: We queried the UNOS database for all heart transplants performed from January 2000 through December 2016. Patients were considered highly sensitized and included if panel-reactive antibody (PRA) activity was 25% or higher. Patients were separated by pretransplant LVAD utilization and subgroup analysis was performed by device type (HeartMate II or HeartWare). Outcomes included Kaplan-Meier survival and episodes of rejection within 1 year of HTx. RESULTS: Of 18 009 recipients, 2434 (14%) were highly sensitized. 1055 (43.3%) were bridged with a VAD. In multivariate analysis, LVAD use did not impact 1-year (hazards ratio [HR], 1.30; P = 0.052) or 5-year survival (HR, 1.18; P = 0.112) in highly sensitized recipients. Furthermore, episodes of rejection were not affected by LVAD status (P = 0.765). Of the 1055 sensitized LVAD-bridged transplant recipients, 624 (59%) were implanted with a HeartMate II and 99 (9.4%) were bridged with a HeartWare device. In multivariate analysis, no differences were observed in 1-year survival (HR, 0.86; P = 0.664), 5-year survival (HR, 1.35; P = 0.209), or episodes of rejection (P = 0.497). CONCLUSIONS: The use of ventricular assist devices did not impact survival or rejection within 1 year of HTx in highly sensitized patients. Highly sensitized recipients have similar outcomes regardless of prior LVAD support or type of LVAD used as a bridge to transplantation.

A Contemporary Analysis of Heart Transplantation and Bridge-to-Transplant Mechanical Circulatory Support Outcomes in Cardiac Sarcoidosis.

BACKGROUND: Patients with end-stage cardiomyopathy due to cardiac sarcoidosis (CS) may be referred for mechanical circulatory support (MCS) and heart transplantation (HT). We describe outcomes of patients with CS undergoing HT, focusing on the use of MCS as a bridge to transplant (BTT). METHODS: Using the United Network for Organ Sharing Scientific Registry of Transplant Recipients, we identified all adult waitlisted patients and isolated HT recipients from 2006 to 2015. These were divided into those with and without CS and further divided into those who did or did not receive MCS as BTT. Outcomes included 1- and 5-year post-transplantation freedom from mortality and 5-year freedom from primary graft failure. RESULTS: Over the study period, 31,528 patients were listed for HT, 148 (0.4%) of whom had CS. Among the CS patients, 34 (23%) received MCS as BTT. 18,348 patients (58%) eventually underwent HT, including 67 (0.4%) with CS, 20 (30%) of whom had received BTT MCS. Compared with non-CS diagnoses, CS patients had similar 1-year (91% vs 90%; log rank P = .88) and 5-year (83% vs 77%; log rank P = .46) freedom from mortality. Survival was also similar between CS BTT and non-CS BTT groups at 1 year (89% vs 89%; log-rank P = .92) and 5 years (72% vs 75%; log-rank P = .77). CONCLUSIONS: Survivals after HT were similar between CS and non-CS patients out to 5 years, and were also similar between CS and non-CS BTT cohorts. Both HT and BTT MCS should be considered in patients with CS.

Correlating Oxygen Delivery During Cardiopulmonary Bypass With the Neurologic Injury Biomarker Ubiquitin C-Terminal Hydrolase L1 (UCH-L1).

OBJECTIVE: The authors sought to assess the relationship between low oxygen delivery (DO2) during cardiopulmonary bypass (CPB) and a neuron-specific biomarker of neurologic injury, ubiquitin C-terminal hydrolase L1 (UCH-L1). DESIGN: Retrospective analysis of patient charts and prospectively collected blood samples. SETTING: University-affiliated tertiary care hospital. PARTICIPANTS: Adult patients undergoing cardiac surgery on CPB. INTERVENTIONS: Serum UCH-L1 levels were drawn at baseline and 6 and 24 hours after CPB cessation. DO2 was computed from perfusion records, with area-under-the-curve (AUC) computations performed to account for distance of DO2 excursions below predefined DO2 thresholds and the amount of time spent below them. Strokes were defined radiographically using computed tomography and magnetic resonance imaging. MEASUREMENTS AND MAIN RESULTS: Forty-three adults were included (median age 65 y, interquartile range 59-72). Three patients experienced strokes (imaged at 2, 7, and 8 d postoperatively). Most patients underwent isolated coronary artery bypass grafting (41%, 18 patients) or isolated aortic valve replacement (30%, 13). Median UCH-L1 levels differed from baseline to 6 and 24 hours after CPB (40, 232, and 166 pg/mL, respectively; p < 0.001). On multivariable linear regression analysis controlling for baseline and surgical variables, only DO2 AUC <225 was significantly associated with 6-hour UCH-L1 levels (p = 0.001), whereas only DO2 AUC <300 was significantly associated with 24- hour levels (p < 0.001). The 3 patients who experienced radiographic strokes had nonsignificantly elevated 24-hour UCH-L1 levels compared with control patients (585 v 151 pg/mL, p = 0.11). CONCLUSIONS: This is the first study to demonstrate an independent association between DO2 during CPB and elevations of a brain injury biomarker; additional study is needed to clarify the clinical significance of these results.

A Novel Risk Score to Predict New Onset Atrial Fibrillation in Patients Undergoing Isolated Coronary Artery Bypass Grafting.

BACKGROUND: Atrial fibrillation (AF) is common after cardiac surgery and contributes to increased morbidity and mortality. Our objective was to derive and validate a predictive model for AF after CABG in patients, incorporating novel echocardiographic and laboratory values. METHODS: We retrospectively reviewed patients at our institution without preexisting dysrhythmia who underwent on-pump, isolated CABG from 2011-2015. The primary outcome was new onset AF lasting >1 hour on continuous telemetry or requiring medical treatment. Patients with a preoperative echocardiographic measurement of left atrial diameter were included in a risk model, and were randomly divided into derivation (80%) and validation (20%) cohorts. The predictors of AF after CABG (PAFAC) score was derived from a multivariable logistic regression model by multiplying the adjusted odds ratios of significant risk factors (P < .05) by a factor of 4 to derive an integer point system. RESULTS: 1307 patients underwent isolated CABG, including 762/1307 patients with a preoperative left atrial diameter measurement. 209/762 patients (27%) developed new onset AF including 165/611 (27%) in the derivation cohort. We identified four risk factors independently associated with postoperative AF which comprised the PAFAC score: age > 60 years (5 points), White race (5 points), baseline GFR < 90 mL/min (4 points) and left atrial diameter > 4.5 cm (4 points). Scores ranged from 0-18. The PAFAC score was then applied to the validation cohort and predicted incidence of AF strongly correlated with observed incidence (r = 0.92). CONCLUSION: The PAFAC score is easy to calculate and can be used upon ICU admission to reliably identify patients at high risk of developing AF after isolated CABG.

Complications of CO2 insufflation during endoscopic vein harvesting.

Over the past few decades, the use of endoscopic harvest of the saphenous vein has gained popularity due to a significant reduction in rates of wound infection and improved cosmesis. The widespread adoption of this technique has introduced a set of complications associated with the use CO2 insufflation which facilitates exposure during the vein harvest. We describe a case of pneumoperitoneum with systemic acidosis and subcutaneous air following endoscopic vein harvest for coronary artery bypass grafting and review the complications that may arise from CO2 insufflation during endoscopic vein harvesting.

Predictors of Late-Onset Atrial Fibrillation Following Isolated Mitral Valve Repairs in Patients With Preserved Ejection Fraction.

BACKGROUND: We sought to determine the incidence of and risk factors for late-onset atrial fibrillation (LOAF) in patients with preserved ejection fractions undergoing mitral valve repair METHODS: We included patients undergoing isolated mitral valve repair (MVR) for degenerative disease between 1997-2014 at our institution with EF ≥60%. Patients who had AF preoperatively were excluded from the final analysis. Our primary outcome, LOAF, was defined as AF occurring after discharge following MVR (≥9 days). RESULTS: 223 patients were included in the study with a mean follow-up of 4.8 ± 4.6 years. A total of 25 patients developed LOAF, and freedom from LOAF was 93.9% at one year, and 87.3% at five years. Patients developing LOAF were of similar mean age (58 vs. 63 years in controls, p = 0.08) and had similar preoperative comorbidities, but did show a trend toward larger left atrial diameter (5.1 vs. 4.7 cm, p = 0.11). After risk adjustment with Cox regression analysis, only increasing left atrial size was associated with LOAF (HR 1.63, p = 0.04). On follow-up, 29 patients (10.8%) developed moderate or greater mitral regurgitation at a mean of 2.2 years. Using a mixed-effects model, we were unable to detect an association between recurrent mitral regurgitation following MVR and LOAF (OR 1.36, p = 0.42). CONCLUSIONS: LOAF occurs in about 13% of preserved ejection fraction patients undergoing MVR by five years. Increasing left atrial diameter is an independent predictor of LOAF. Concomitant anti-arrhythmic procedures may warrant further investigation in patients with preserved ejection fraction and enlarged left atria undergoing MVR. doi: 10.1111/jocs.12774 (J Card Surg 2016;31:486-492).

A Predictive Model and Risk Score for Unplanned Cardiac Surgery Intensive Care Unit Readmissions.

BACKGROUND: Readmissions or "bounce back" to the intensive care unit (ICU) following cardiac surgery is associated with an increased risk of morbidity and mortality. We sought to identify clinical and system-based factors associated with ICU bounce backs in order to generate a Bounce Back After Transfer (BATS) prediction score. METHODS: We prospectively collected the clinical and financial records of all patients undergoing coronary artery bypass grafting (CABG) or surgical aortic valve replacement (AVR) between May 2013 and March 2014. Multivariable logistic regression was used to identify independent predictors of bounce backs to the ICU which served as the basis for our BATS score. RESULTS: Of the 532 patients that underwent CABG or AVR during the study period, 35 (6.6%) were readmitted to the ICU. After risk adjustment, female sex, NYHA class III/IV, urgent or emergent operative status, and postoperative renal failure were the predictors of ICU bounce backs utilized to create the BATS score. Patients in the low (<5), moderate (5-10), and high-risk (>10) score cohorts experienced bounce back rates of 3.0%, 10.4%, and 42%, respectively. After adjusting for preoperative patient risk, ICU bounce back resulted in an increase in $68,030 to a patient's total hospital charges. CONCLUSIONS: A predictive model (BATS) can determine the risk of a bounce back to the ICU after transfer to the floor. We speculate that determination of a patient's BATS upon ICU transfer would allow targeted floor care and decrease bounce back rates, along with postoperative morbidity, mortality, and cost of care.

Early Intervention in Asymptomatic Aortic Stenosis: What Are We Waiting For?

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.

Beyond Static Planning: Computational Predictive Modeling to Avoid Coronary Artery Occlusion in TAVR.

BACKGROUND: Coronary artery occlusion (CO) during transcatheter aortic valve replacement (TAVR) is a devastating complication. The objective is to assess the clinical impact of a novel computational predictive modeling algorithm for CO during TAVR planning. METHODS: From January 2020 to December 2022, 116 patients (7.6%) undergoing TAVR evaluation were deemed at increased risk of CO based on traditional criteria. Patients underwent prospective computational modeling (DASI Simulations) to assess 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 stenosis(45.7%), 47 a previous surgical AVR (40.5%), and 16 a prior TAVR (13.8%). Transcatheter valve choice, size, and/or implantation depth was modeled for all patients. Computational modeling predicted an increased risk of CO based in 39/116 (31.9%). Within this sub-cohort, 29 patients proceeded with TAVR. Procedural modifications to augment risk of CO included BASILICA (n=10), chimney coronary stents (n=8), coronary access without stent (n=3). There were no episodes of coronary compromise among patients following TAVR, either for those predicted to be at high risk of CO (with procedural modifications) or predicted low risk (standard TAVR). CONCLUSIONS: Utilization of preoperative simulations for TAVR in patient-specific geometry through computational predictive modeling of CO was an effective enhancement to procedure planning.

Laparoscopic rectopexy for rectal prolapse to reduce surgical-site infections and length of stay.

BACKGROUND: Rectal prolapse is commonly seen in patients with significant co-morbidities. Multiple approaches have been described, including the use of laparoscopy. The purpose of this study was to determine if laparoscopic approaches for repair of rectal prolapse are associated with less short-term morbidity than open approaches. METHODS: The American College of Surgeons National Surgical Quality Improvement Program database was queried for patients who underwent laparoscopic or open rectopexy (R) or sigmoid resection and rectopexy (SR + R) between 2005 and 2008. Co-morbidities analyzed included diabetes, body mass index, chronic obstructive pulmonary disease, hypertension, cardiac (history of congestive heart failure, myocardial infarction, peripheral vascular disease, previous percutaneous cardiac intervention or surgery), and neurologic disorder (history of transient ischemic attack or cerebrovascular accident). Postoperative complications analyzed included surgical-site infections (SSIs), pneumonia, reintubation, pulmonary embolus, stroke, myocardial infarction, and sepsis. The χ (2) or t test/ANOVA were used to assess significance for categoric and continuous variables, respectively. Logistic regression analysis was used to determine risk factors for morbidity after rectal prolapse repair. RESULTS: Altogether, 685 patients underwent surgical treatment of rectal prolapse. Most patients underwent open SR + R (open: 247 SR + R, 193 R; laparoscopic: 161 SR + R, 84 R). All patients had similar co-morbidity profiles. Patients undergoing laparoscopic R were significantly older (mean age 61.4 years) than those in the other three groups (p = 0.04). Operating time ranged from 128 min (open R) to 185 min (laparoscopic SR + R; p < 0.001). Open SR + R and open R were associated with significantly more morbidity than laparoscopic SR + R and R [odds ratio (OR) 0.42, 95 % confidence interval (CI) 0.22-0.83, p = 0.01]. Comparing all four procedures, there was a trend to decreased overall morbidity with laparoscopic R, but without statistical significance (OR 0.31, 95 % CI 0.07-1.40, p = 0.13). Length of hospital stay (LOS) and SSI rates were significantly lower with laparoscopic R than with the other three procedures. CONCLUSIONS: Patients who undergo laparoscopic rectopexy have a shorter LOS and lower SSI rate than patients who undergo other abdominal procedures for repair of rectal prolapse. Further study is necessary to determine the long-term outcomes from laparoscopic rectopexy, but in high-risk patients the laparoscopic approach can decrease perioperative risk.

Technology and health information technology in colorectal surgery: electronic literature support.

The advent of the Internet has revolutionized the management of reporting and accessing research and data. The authors review the current resources available to surgeons through websites, accumulated published data repositories, and libraries. The change in how we publish and present peer-reviewed data over the last 20 years is also discussed as well as the future of health information technology.

Correlating oxygen delivery on cardiopulmonary bypass with Society of Thoracic Surgeons outcomes following cardiac surgery.

BACKGROUND: The relationship between low oxygen delivery (DO2) on cardiopulmonary bypass and morbidity and mortality following cardiac surgery remains unexamined. METHODS: We reviewed patients undergoing Society of Thoracic Surgeons index procedures from March 2019 to July 2020, coincident with implementation of a new electronic perfusion record that provides for continuous recording of DO2 and flow parameters. Continuous perfusion variables were analyzed using area-over-the-curve (AOC) calculations below predefined thresholds (DO2 <280 mL O2/min/m2, cardiac index <2.2 L/min, hemoglobin < baseline, and mean arterial pressure <65 mm Hg) to quantify depth and duration of potentially harmful exposures. Multivariable logistic regression adjusted by Society of Thoracic Surgeons predicted-risk scores were used to assess for relationship of perfusion variables with the primary composite outcome of any Society of Thoracic Surgeons index procedure, as well as individual Society of Thoracic Surgeons secondary outcomes (eg, mortality, renal failure, prolonged ventilation >24 hours, stroke, sternal wound infection, and reoperation). RESULTS: Eight hundred thirty-four patients were included; 42.7% (356) underwent isolated coronary artery bypass grafting (CABG), whereas 57.3% underwent nonisolated CABG (eg, valvular or combined CABG/valvular operations). DO2 <280-AOC trended toward association with the primary outcome across all cases (P = .07), and was significantly associated for all nonisolated CABG cases (P = .02)-more strongly than for cardiac index <2.2-AOC (P = .04), hemoglobin <7-AOC (P = .51), or mean arterial pressure <65-AOC (P = .11). Considering all procedures, DO2 <280-AOC was independently associated prolonged ventilation >24 hours (P = .04), an effect again most pronounced in nonisolated-CABG cases (P = .002), as well as acute kidney injury <72 hours (P = .04). Patients with glomerular filtration rate <65 mL/min and baseline hemoglobin <12.5 g/dL appeared especially vulnerable. CONCLUSIONS: Low DO2 on bypass may be associated with morbidity/mortality following cardiac surgery, particularly in patients undergoing nonisolated CABG. These results underscore the importance of goal-directed perfusion strategies.

Hyperinsulinemic hypoglycemia after Roux-en-Y gastric bypass: unraveling the role of gut hormonal and pancreatic endocrine dysfunction.

BACKGROUND: Profound hypoglycemia occurs rarely as a late complication after Roux-en-Y gastric bypass (RYGB). We investigated the role of glucagon-like-peptide-1 (GLP-1) in four subjects who developed recurrent neuro-glycopenia 2 to 3 y after RYGB. METHODS: A standardized test meal (STM) was administered to all four subjects. A 2 h hyperglycemic clamp with GLP-1 infusion during the second hour was performed in one subject, before, during a 4 wk trial of octreotide (Oc), and after 85% distal pancreatectomy. After cessation of both glucose and GLP-1 infusion at the end of the 2 h clamp, blood glucose levels were monitored for 30 min. Responses were compared with a control group (five subjects 12 mo status post-RYGB without hypoglycemic symptoms). RESULTS: During STM, both GLP-1 and insulin levels were elevated 3- to 4-fold in all subjects, and plasma glucose-dependent insulinotropic peptide (GIP) levels were elevated 2-fold. Insulin responses to hyperglycemia ± GLP-1 infusion in one subject were comparable to controls, but after cessation of glucose infusion, glucose levels fell to 40 mg/dL. During Oc, the GLP-1 and insulin responses to STM were reduced (>50%). During the clamp, insulin response to hyperglycemia alone was reduced, but remained unchanged during GLP-1. Glucagon levels during hyperglycemia alone were suppressed and further suppressed after the addition of GLP-1. With the substantial drop in glucose during the 30 min follow-up, glucagon levels failed to rise. Due to persistent symptoms, one subject underwent 85% distal pancreatectomy; postoperatively, the subject remained asymptomatic (blood glucose: 119-220 mg/dL), but a repeat STM showed persistence of elevated levels of GLP-1. Histologically enlarged islets, and ß-cell clusters scattered throughout the acinar parenchyma were seen, as well as ß-cells present within pancreatic duct epithelium. An increase in pancreatic and duodenal homeobox-1 protein (PDX-1) expression was observed in the subject compared with control pancreatic tissue. CONCLUSIONS: A persistent exaggerated hypersecretion of GLP-1, which has been shown to be insulinotropic, insulinomimetic, and glucagonostatic, is the likely cause of post-RYGB hypoglycemia. The hypertrophy and ectopic location of ß-cells is likely due to overexpression of the islet cell transcription factor, PDX-1, caused by prolonged hypersecretion of GLP-1.

Impact of the New Pulmonary Hypertension Definition on Heart Transplant Outcomes: Expanding the Hemodynamic Risk Profile.

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.

Children's Heart Assessment Tool for Transplantation (CHAT) Score: A Novel Risk Score Predicts Survival After Pediatric Heart Transplantation.

BACKGROUND: Given the shortage of donor organs in pediatric heart transplantation (HTx), pretransplant risk stratification may assist in organ allocation and recipient optimization. We sought to construct a scoring system to preoperatively stratify a patient's risk of one-year mortality after HTx. METHODS: The United Network for Organ Sharing database was queried for pediatric (<18 years) patients undergoing HTx between 2000 and 2016. The population was randomly divided in a 4:1 fashion into derivation and validation cohorts. A multivariable logistic regression model for one-year mortality was constructed within the derivation cohort. Points were then assigned to independent predictors ( P < .05) based on relative odds ratios (ORs). Risk groups were established based on easily applicable, whole-integer score cutoffs. RESULTS: A total of 5,700 patients underwent HTx; one-year mortality was 10.7%. There was a similar distribution of variables between derivation (n = 4,560) and validation (n = 1,140) cohorts. Of the 12 covariates included in the final model, nine were allotted point values. The low-risk (score 0-9), intermediate-risk (10-20), and high-risk (>20) groups had a 5.18%, 10%, and 28% risk of one-year mortality ( P < .001), respectively. Both intermediate-risk (OR = 2.46, 95% confidence interval [95% CI]: 1.93-3.15; P < .001) and high-risk (OR = 9.24, 95% CI: 6.92-12.35; P < .001) scores were associated with an increased risk of one-year mortality when compared to the low-risk group. CONCLUSIONS: The Children's Heart Assessment Tool for Transplantation score represents a pediatric-specific, recipient-based system to predict one-year mortality after HTx. Its use could assist providers in identification of patients at highest risk of poor outcomes and may aid in pretransplant optimization of these children.