Inclusive ABO-Incompatible Listing for Pediatric Heart Transplantation Results in Comparable Post-Transplant Rejection-Free Survival in a Single-Center Series.

ABO-incompatible (ABOi) heart transplantation (HT) has increased organ availability for infants with end-stage heart failure. Despite increasing adoption of ABOi listing for HT, data remain limited regarding pre- and post-HT immunologic profiles to guide listing practices and post-HT follow-up. Thus, the purpose of this study was to evaluate post-HT outcomes at a single center employing inclusive ABOi listing irrespective of pre-HT isohemagglutinin titers. All HT recipients listed at less than 24 months of age at our institution from 2010-2020 were included. Pre- and post-operative variables were compared for ABOi and ABO-compatible (ABOc) recipients. Separate iso-IgG and iso-IgM titers were monitored pre- and post-HT. Primary outcomes were compared between ABOi versus ABOc groups at mid-term follow-up. 51 HTs were performed on 50 patients from 2010-2020 (ABOi, N = 13; ABOc, N = 38). Six ABOi recipients received intra-operative plasma exchange for elevated titers (greater than 1:8 for IgG or IgM or reverse type greater than 2 +). Treated rejection, DSA, CAV, primary graft failure, need for re-HT, and survival were comparable between ABOi and ABOc groups at mid-term follow-up. An inclusive approach to ABOi HT listing for infants less than 24 months of age results in comparable post-transplant rejection-free survival, CAV, and prevalence of DSA at mid-term follow-up. These data define a potential role for specific IgM and IgG testing to promote understanding of risk stratification in pediatric ABOi listing, and support an inclusive strategy irrespective of high pre-HT titers to expand the number of available donor hearts for infants and older children awaiting HT.

Out of the blue: inflammatory myofibroblastic tumour identified during repair of tetralogy of Fallot with absent pulmonary valve.

Inflammatory myofibroblastic tumour of the heart is an exceedingly rare benign neoplasm. While benign, without prompt management its impact can be devastating. Tetralogy of Fallot with absent pulmonary valve is a rare form of CHD. We present the first documented case of inflammatory myofibroblastic tumour of the heart in the presence of tetralogy of Fallot with absent pulmonary valve.

Use of aortic wall patches as leaflet replacement material during aortic valve repair.

Objectives: Aortic valve repair can be limited by inadequate leaflet tissue for proper coaptation. Various kinds of pericardium have been used for cusp augmentation, but most have failed because of tissue degeneration. A more durable leaflet substitute is needed. Methods: In this report, 8 consecutive cases are presented in which autologous ascending aortic tissue was used to augment inadequate native cusps during aortic valve repair. Biologically, aortic wall is a living autologous tissue that could have exceptional durability as a leaflet substitute. Techniques for insertion are described in detail, along with procedural videos. Results: Early surgical outcomes were excellent, with no operative mortalities or complications, and all valves were competent with low valve gradients. Patient follow-up and echocardiograms to a maximum of 8 months' postrepair remain excellent. Conclusions: Because of superior biologic characteristics, aortic wall has the potential to provide a better leaflet substitute during aortic valve repair and to expand patient categories amenable to autologous reconstruction. More experience and follow-up should be generated.

Development of a Modular and Equitable Surgical Simulator.

There is a tremendous need for affordable and accessible surgical simulators in the United States and abroad. Our group developed a portable, modular, inexpensive surgical simulator designed for all levels of surgical trainees, from medical students to cardiothoracic surgery fellows, and adaptable to a variety of surgical specialties. Our goal is to provide a platform for innovative surgery simulation that applies to any learner or resource setting. We describe the development, assembly, and future directions for this simulator.

Endovascular repair of left ventricular assist device outflow graft defect.

Outflow graft complications after left ventricular assist device placement are infrequent but highly morbid. In this case report, we describe endovascular repair of multiple outflow graft defects with external hemorrhage in a complex patient using overlapping stent grafts. This approach successfully stopped the outflow graft hemorrhage and temporized the patient for subsequent cardiac transplantation.

Goal-directed resuscitation following cardiac surgery reduces acute kidney injury: A quality initiative pre-post analysis.

OBJECTIVE: Acute kidney injury (AKI) occurs in 20% of patients following cardiac surgery. To reduce AKI in our institution, we instituted a quality improvement (QI) initiative using a goal-directed volume resuscitation protocol. Our protocol was designed to achieve quantifiable physiologic goals (eg, cardiac index > 2.5 L/min/m2, mean arterial pressure > 65 mm Hg) using fluid and vasoactive agents. The objective of this study was to evaluate AKI in the pre- and post-QI eras, hypothesizing that AKI incidence would decrease in the post-QI era. METHODS: In this observational retrospective cohort study, we identified patients who underwent cardiac operations from July 2011 to July 2015 with a risk score available. Kidney injury was determined using the lowest postoperative GFR within 7 days of surgery and standard Risk, Injury, Failure, Loss of Kidney Function, and End-Stage Kidney Disease (RIFLE) classification criteria. The primary outcome was the rate of AKI, as defined by glomerular filtration rate-based RIFLE classification criteria injury, in the post- versus pre-QI eras. RESULTS: A total of 1979 patients were included, of whom 725 were in the pre-QI cohort, and 1254 in the post-QI cohort. Overall, rates of RIFLE classification criteria risk, injury and failure were 27.5%, 5.9%, and 3.6%, respectively. RIFLE classification criteria injury saw the largest decrease in the post-QI cohort (8.1% vs 4.6%; P = .001). Multivariable analysis demonstrated a 37% reduction in the odds of AKI in the post-QI cohort (adjusted odds ratio, 0.63; 95% confidence interval, 0.43-0.90). CONCLUSIONS: A goal-directed volume resuscitation protocol centered on patient fluid responsiveness is associated with significantly reduced risk for AKI after cardiac surgery. Protocol-driven approaches should be employed in intensive care units to improve outcomes.

Heparin-Induced Thrombocytopenia and Cardiac Surgery.

Heparin-induced thrombocytopenia (HIT) is an immune-mediated condition characterized by thrombocytopenia with possible arterial and/or venous thrombosis. The overall incidence of HIT is low but ranges from 0.1% to 5%.1,2 The incidence can be as high as 3% in patients undergoing cardiac surgery. The use of unfractionated heparin (UFH) is ubiquitous in patients who undergo cardiac procedures and carries a 10-fold higher incidence of HIT over low molecular weight heparin. Patients undergoing cardiac surgery thus form a unique group that warrants specific attention to this clinicopathologic entity considering the relatively high incidence and associated morbidity and mortality with a delay in diagnosis. In this article, we will discuss 5 clinical aspects pertinent to the diagnosis and management of HIT in cardiac surgery patients and review the current literature.

Good at One or Good at All? Variability of Coronary and Valve Operation Outcomes Within Centers.

BACKGROUND: The technical expertise required for treatment of coronary and structural heart valve disease differs. Correlation between center-specific mortality rates after coronary artery bypass grafting (CABG) and valve operations has not been demonstrated. This study tested the hypothesis that risk-adjusted outcomes between coronary and valve procedures do not correlate within centers. METHODS: Records of patients undergoing isolated CABG, isolated aortic valve replacement (AVR), or isolated mitral valve replacement (MVR) procedures from 2008 to 2015 in a multi-institutional Society of Thoracic Surgeons (STS) database were used to generate observed-to-expected (O/E) ratios for morbidity and death. Ratios were based on the STS predicted risks of morbidity and death and were calculated by procedure for each institution. Linear regression models evaluated the relationship between institutional performance in CABG and valve operations. RESULTS: A total of 22,258 records from 18 institutions were analyzed: 17,026 CABG, 3,238 isolated AVR, and 1,994 MVR procedures. With respect to deaths, the correlation coefficients were weak; for AVR and CABG, it was 0.22 and was 0.26 for MVR and CABG. With respect to morbidity, a strong relationship was seen between the morbidity O/E ratios, with coefficients of 1.03 for AVR and 0.97 for MVR, suggesting a nearly 1:1 relationship between morbidities observed in an institution's CABG and valve operations. CONCLUSIONS: Sites that perform CABG with low mortality rates may not have similarly low mortality rates with valve operations. Most striking, however, is the nearly identical O/E ratio for morbidity for CABG and valve operations at each center. These findings suggest postoperative care as a major determinant for morbidity after cardiac operation.

Outcomes for Low-Risk Surgical Aortic Valve Replacement: A Benchmark for Aortic Valve Technology.

BACKGROUND: Two large, randomized trials are underway evaluating transcatheter aortic valve replacement (AVR) against conventional surgical AVR. We analyzed contemporary, real-world outcomes of surgical AVR in low-risk patients to provide a practical benchmark of outcomes and cost for evaluating current and future transapical AVR technology. METHODS: From 2010 to 2015, 2,505 isolated AVR operations were performed for severe aortic stenosis at 18 statewide cardiac institutions. Of these, 2,138 patients had a Society of Thoracic Surgeons predicted risk of mortality of less than 4%, and 1,119 met other clinical and hemodynamic criteria as outlined in the PARTNER 3 (The Placement of Transcatheter Aortic Valves) protocol. Patients with endocarditis, end-stage renal disease, ejection fraction of less than 0.45, bicuspid valves, and previous valve replacements were excluded. Outcomes of interest included operative death and postoperative adverse events. RESULTS: The median Society of Thoracic Surgeons predicted risk of mortality for the study-eligible patients was 1.44%, with a median age of 72 years (interquartile range [IQR], 65 to 78 years). Operative mortality was 1.3%, permanent stroke was 1.3%, and pacemaker requirement was 4.2%. The most common adverse events were transfusion of 2 or more units of red blood cells (18%) and atrial fibrillation (28%). The median length of stay was 6 days (IQR, 5 to 8 days). Median total hospital cost was $37,999 (IQR, $30,671 to $46,138). Examination of complications by age younger than 65 vs 65 or older demonstrated a significantly lower need for transfusion (11.2%, p < 0.001) and incidence of atrial fibrillation (17.1%, p < 0.001) but no difference in operative mortality (2.2% vs 0.9%, p = 0.1), major morbidity (10.4% vs 12.6%, p = 0.3), or total hospital costs. CONCLUSIONS: Low-risk patients undergoing surgical AVR in the current era have excellent results. The most common complications were atrial fibrillation and bleeding. These real-world results should provide additional context for upcoming transcatheter clinical trial data.

Regional Practice Patterns and Outcomes of Surgery for Acute Type A Aortic Dissection.

BACKGROUND: The surgical management of acute type A aortic dissection is evolving, and many aortic centers of excellence are reporting superior outcomes. We hypothesize that similar trends exist in a multiinstitutional regional consortium. METHODS: Records for 884 consecutive patients who underwent aortic operations (2003 to 2015) for acute type A aortic dissection were extracted from a regional The Society of Thoracic Surgeons database. Patients were stratified into three equal operative eras. Differences in outcomes and risk factors for morbidity and mortality were determined. RESULTS: Surgical procedures for type A aortic dissection are increasing in extent and complexity. Aortic root repair was performed in 16% of early era cases compared with 67% currently (p < 0.0001). Similarly, aortic arch repair increased from 27% to 37% cases (p < 0.0001). Cerebral perfusion is currently used in 85% of circulatory arrest cases, most frequently antegrade (57%). Total circulatory arrest times increased (29 minutes vs 31 minutes vs 36 minutes; p = 0.005), but times without cerebral perfusion were stable (12 minutes vs 6 minutes; p = 0.68). Although the operative mortality rate remained stable at 18.9% during the 3 operative eras, there were significant decreases in pneumonia and reoperations (p < 0.05). Predictors of operative mortality and major morbidity are age (odds ratio [OR], 1.04; p < 0.0001), previous stroke (OR, 2.09; p = 0.03), and elevated creatinine (OR, 1.31; p = 0.01). Importantly, the extent of aortic operation did not increase risk for morbidity or mortality. CONCLUSIONS: Operative morbidity and mortality remain significant for type A aortic dissection, but lower than historical outcomes. The extent of aortic surgery has increased, resulting in adaptive cerebral protection changes in contemporary "real-world" practice.

Impact of Transcatheter Technology on Surgical Aortic Valve Replacement Volume, Outcomes, and Cost.

BACKGROUND: Transcatheter aortic valve replacement (TAVR) represents a disruptive technology that is rapidly expanding in use. We evaluated the effect on surgical aortic valve replacement (SAVR) patient selection, outcomes, volume, and cost. METHODS: A total of 11,565 patients who underwent SAVR, with or without coronary artery bypass grafting (2002 to 2015), were evaluated from the Virginia Cardiac Services Quality Initiative database. Patients were stratified by surgical era: pre-TAVR era (2002 to 2008, n = 5,113), early-TAVR era (2009 to 2011, n = 2,709), and commercial-TAVR era (2012 to 2015, n = 3,743). Patient characteristics, outcomes, and resource utilization were analyzed by univariate analyses. RESULTS: Throughout the study period, statewide SAVR volumes increased with median volumes of pre-TAVR: 722 cases/year, early-TAVR: 892 cases/year, and commercial-TAVR: 940 cases/year (p = 0.005). Implementation of TAVR was associated with declining Society of Thoracic Surgeons predicted risk of mortality among SAVR patients (3.7%, 2.6%, and 2.4%; p < 0.0001), despite increasing rates of comorbid disease. The mortality rate was lowest in the current commercial-TAVR era (3.9%, 4.3%, and 3.2%; p = 0.05), and major morbidity decreased throughout the time period (21.2%, 20.5%, and 15.2%; p < 0.0001). The lowest observed-to-expected ratios for both occurred in the commercial-TAVR era (0.9 and 0.9, respectively). Resource utilization increased generally, including total cost increases from $42,835 to $51,923 to $54,710 (p < 0.0001). CONCLUSIONS: At present, SAVR volumes have not been affected by the introduction of TAVR. The outcomes for SAVR continue to improve, potentially due to availability of transcatheter options for high-risk patients. Despite rising costs for SAVR, open approaches still provide a significant cost advantage over TAVR.

A novel chronic advanced stage abdominal aortic aneurysm murine model.

OBJECTIVE: The purpose of this study was to establish a reliable, chronic model of abdominal aortic aneurysm (AAA). METHODS: Wild-type 8-week-old C56BL/6 male mice (n = 120) were equally divided into three groups: (1) BAPN group: 0.2% 3-aminopropionitrile fumarate salt (BAPN) drinking water was provided to mice 2 days before surgery until the end of study. Sham aneurysm induction surgery was performed using 5 µL of heat deactivated elastase. (2) Elastase group: mice were given regular drinking water without BAPN. During aneurysm induction surgery, 5 µL of the active form of elastase (10.3 mg protein/mL, 5.9 U/mg protein) was applied on top of the infrarenal abdominal aorta adventitia for 5 minutes. (3) BAPN+elastase group: mice were given BAPN drinking water and the active form of elastase application, as above. On postoperative days 7, 14, 21, 28, and 100, aortic samples were collected for histology, cytokine array, and gelatin zymography after aortic diameter measurement. RESULTS: Compared with the elastase group, the BAPN+elastase group had a higher AAA formation rate (93% vs 65%; P < .01) with more advanced AAAs (25 of 42 vs 1 of 40 for stage II and III; P < .001). Aneurysms from the BAPN+elastase group demonstrated persistent long-term growth (221.5% ± 36.6%, 285.8% ± 78.6%, and 801% ± 160% on days 21, 28, and 100, respectively; P < .001), with considerable thrombus formation (54%) and rupture (31%) at the advanced stages of AAA development. Cytokine levels (pro-matrix metalloproteinase 9, interleukin-1ß, interleukin-6, chemokine [C-C motif] ligand 5, triggering receptor expressed on myeloid cells 1, monocyte chemotactic protein 1, and tissue inhibitor of metalloproteinase 1) in the BAPN+elastase group were higher than in the elastase group on day 7. After day 7, cytokine levels returned to baseline, with the exception of elevated matrix metalloproteinase 2 activity. By histology, CD3-positive T cells in the BAPN+elastase group were elevated on days 28 and 100. CONCLUSIONS: A combination of oral BAPN administration and periaortic elastase application induced a chronic, advanced-stage AAA with characteristics of persistent aneurysm growth, thrombus formation, and spontaneous rupture. Future studies should use this model, especially for examining tissue remodeling during the late stages of aneurysm development.

Postoperative Hypoglycemia Is Associated With Worse Outcomes After Cardiac Operations.

BACKGROUND: Hypoglycemia is a known risk of intensive postoperative glucose control in patients undergoing cardiac operations. However, neither the consequences of hypoglycemia relative to hyperglycemia, nor the possible interaction effects, have been well described. We examined the effects of postoperative hypoglycemia, hyperglycemia, and their interaction on short-term morbidity and mortality. METHODS: Single-institution Society of Thoracic Surgeons (STS) database patient records from 2010 to 2014 were merged with clinical data, including blood glucose values measured in the intensive care unit (ICU). Exclusion criteria included fewer than three glucose measurements and absence of an STS predicted risk of morbidity or mortality score. Primary outcomes were operative mortality and composite major morbidity (permanent stroke, renal failure, prolonged ventilation, pneumonia, or myocardial infarction). Secondary outcomes included ICU and postoperative length of stay. Hypoglycemia was defined as below 70 mg/dL, and hyperglycemia as above 180 mg/dL. Simple and multivariable regression models were used to evaluate the outcomes. RESULTS: A total of 2,285 patient records met the selection criteria for analysis. The mean postoperative glucose level was 140.8 ± 18.8 mg/dL. Overall, 21.4% of patients experienced a hypoglycemic episode (n = 488), and 1.05% (n = 24) had a severe hypoglycemic episode (<40 mg/dL). The unadjusted odds ratio (UOR) for operative mortality for patients with any hypoglycemic episode compared with those without was 5.47 (95% confidence interval [CI] 3.14 to 9.54), and the UOR for major morbidity was 4.66 (95% CI 3.55 to 6.11). After adjustment for predicted risk of morbidity or mortality and other significant covariates, the adjusted odds (AOR) of operative mortality were significant for patients with any hypoglycemia (AOR 4.88, 95% CI 2.67 to 8.92) and patients with both events (AOR 8.29, 95% CI 1.83 to 37.5) but not hyperglycemia alone (AOR 1.62, 95% CI 0.56 to 4.69). The AOR of major morbidity for patients with both hypoglycemic and hyperglycemic events was 14.3 (95% CI 6.50 to 31.4). CONCLUSIONS: Postoperative hypoglycemia is associated with both mortality and major morbidity after cardiac operations. The combination of both hyperglycemia and hypoglycemia represents a substantial increase in risk. Although it remains unclear whether hypoglycemia is a cause, an early warning sign, or a result of adverse events, this study suggests that hypoglycemia may be an important event in the postoperative period after cardiac operations.

B-Cell Depletion Promotes Aortic Infiltration of Immunosuppressive Cells and Is Protective of Experimental Aortic Aneurysm.

OBJECTIVE: B-cell depletion therapy is widely used for treatment of cancers and autoimmune diseases. B cells are abundant in abdominal aortic aneurysms (AAA); however, it is unknown whether B-cell depletion therapy affects AAA growth. Using experimental models of murine AAA, we aim to examine the effect of B-cell depletion on AAA formation. APPROACH AND RESULTS: Wild-type or apolipoprotein E-knockout mice were treated with mouse monoclonal anti-CD20 or control antibodies and subjected to an elastase perfusion or angiotensin II infusion model to induce AAA, respectively. Anti-CD20 antibody treatment significantly depleted B1 and B2 cells, and strikingly suppressed AAA growth in both models. B-cell depletion resulted in lower circulating IgM levels, but did not affect the levels of IgG or cytokine/chemokine levels. Although the total number of leukocyte remained unchanged in elastase-perfused aortas after anti-CD20 antibody treatment, the number of B-cell subtypes was significantly lower. Interestingly, plasmacytoid dendritic cells expressing the immunomodulatory enzyme indole 2,3-dioxygenase were detected in the aortas of B-cell-depleted mice. In accordance with an increase in indole 2,3-dioxygenase+ plasmacytoid dendritic cells, the number of regulatory T cells was higher, whereas the expression of proinflammatory genes was lower in aortas of B-cell-depleted mice. In a coculture model, the presence of B cells significantly lowered the number of indole 2,3-dioxygenase+ plasmacytoid dendritic cells without affecting total plasmacytoid dendritic cell number. CONCLUSIONS: The present results demonstrate that B-cell depletion protects mice from experimental AAA formation and promotes emergence of an immunosuppressive environment in aorta.

Usefulness of Psoas Muscle Area to Predict Mortality in Patients Undergoing Transcatheter Aortic Valve Replacement.

Frailty has become high-priority theme in cardiovascular diseases because of aging and increasingly complex nature of patients. Low muscle mass is characteristic of frailty, in which invasive interventions are avoided if possible because of decreased physiological reserve. This study aimed to determine if the psoas muscle area (PMA) could predict mortality and to investigate its utility in patients who underwent transcatheter aortic valve replacement (TAVR). We retrospectively reviewed 232 consecutive patients who underwent TAVR. Cross-sectional areas of the psoas muscles at the level of fourth lumbar vertebra were measured by computed tomography and normalized to body surface area. Patients were divided into tertiles according to the normalized PMA for each gender (men: tertile 1, 1,708 to 1,178 mm(2)/m(2); tertile 2, 1,176 to 1,011 mm(2)/m(2); and tertile 3, 1,009 to 587 mm(2)/m(2); women: tertile 1, 1,436 to 962 mm(2)/m(2); tertile 2, 952 to 807 mm(2)/m(2); and tertile 3, 806 to 527 mm(2)/m(2)). Smaller normalized PMA was independently correlated with women and higher New York Heart Association classification. After adjustment for multiple confounding factors, the normalized PMA tertile was independently associated with mortality at 6 months (adjusted hazard ratio 1.53, 95% confidence interval 1.06 to 2.21). Kaplan-Meier analysis showed that tertile 3 had higher mortality rates than tertile 1 at 6 months (14% and 31%, respectively, p = 0.029). Receiver-operating characteristic analysis showed that normalized PMA provided the increase of C-statistics for predicting mortality for a clinical model and gait speed. In conclusion, PMA is an independent predictor of mortality after TAVR and can complement a clinical model and gait speed.

Enteral Access is not Required for Esophageal Cancer Patients Undergoing Neoadjuvant Therapy.

BACKGROUND: The nutritional status of esophageal cancer patients during neoadjuvant therapy remains a challenging problem. The objective of this study was to determine whether routine enteral feeding tube placement improved nutritional status and perioperative outcomes for patients undergoing neoadjuvant therapy for esophageal cancer. METHODS: The Society of Thoracic Surgeons database was used to identify patients who underwent neoadjuvant therapy and esophagectomy at our institution between 2010 and 2014. Nutritional status before and after neoadjuvant therapy was determined through standardized nutrition consultations. Predictors of change in nutrition and adverse events were evaluated with multivariable and univariate logistic regressions. RESULTS: Two hundred thirty-four esophagectomy patients were identified, and 127 (54%) received neoadjuvant therapy. Of those receiving neoadjuvant therapy, 80% (102/127) presented with dysphagia, and 48% (61/127) received enteral feeding access (EA). Multivariable regression revealed that high initial albumin level, high initial body mass index, and presence of EA were associated with nutritional stability during neoadjuvant therapy. However, 27.9% (17/61) of patients who received EA did not use their access at all or did not use it consistently during the course of preoperative treatment. The preoperative grades of malnutrition and esophagectomy outcomes were similar between groups (EA vs no EA). CONCLUSIONS: EA is associated with improved nutritional status for patients undergoing neoadjuvant therapy for esophageal cancer. However, adverse events and suboptimal use are common. Esophagectomy outcomes were similar for patients with and without EA. These results support judicious patient selection for EA, expedited neoadjuvant therapy, and close collaboration with nutritionists.

Minimally Invasive Atrial Fibrillation Surgery: Hybrid Approach.

Atrial fibrillation is a challenging pathologic process. There continues to be a great need for the development of a reproducible, durable cure when medical management has failed. An effective, minimally invasive, sternal-sparing intervention without the need for cardiopulmonary bypass is a promising treatment approach. In this article, we describe a hybrid technique being refined at our center that combines a thoracoscopic epicardial surgical approach with an endocardial catheter-based procedure. We also discuss our results and review the literature describing this unique treatment approach.