Comparison of open thoracoabdominal repair for chronic aortic dissections and aneurysms.

OBJECTIVE: Aortic dissection is common in patients undergoing open surgical repair of thoracoabdominal aortic aneurysms (TAAAs). Most often, dissection is chronic and is associated with progressive aortic dilatation. Because contemporary outcomes in chronic dissection are not clearly understood, we compared patient characteristics and outcomes after open TAAA repair between patients with chronic dissection and those with non-dissection aneurysm. METHODS: We retrospectively analyzed data from 3470 open TAAA repairs performed in a single practice. Operations were for non-dissection aneurysm in 2351 (67.8%) and chronic dissection in 1119 (32.2%). Outcomes included operative mortality and adverse events, a composite variable comprising operative death and persistent (present at discharge) stroke, paraplegia, paraparesis, and renal failure necessitating dialysis. Logistic regression identified predictors of operative mortality and adverse events. Time-to-event analyses examined survival, death, repair failure, subsequent progressive repair, and survival free of failure or subsequent repair. RESULTS: Compared with patients with non-dissection aneurysm, those with chronic dissection were younger, had fewer atherosclerotic risk factors, and were more likely to have heritable thoracic aortic disease and undergo extent II repair. The operative mortality rate was 8.5% (n = 296) overall and was higher in non-dissection aneurysm patients (n = 217; 9.2%) than in chronic dissection patients (n = 79; 7.1%; P = .03). Adverse events were less frequent (P = .01) in patients with chronic dissection (n = 145; 13.0%), 22 (2.0%) of whom had persistent paraplegia. Chronic dissection was not predictive of operative mortality (P = .5) or adverse events (P = .6). Operative mortality and adverse events, respectively, were independently predicted by emergency repair (odds ratio [OR], 3.46 and 2.87), chronic kidney disease (OR, 1.74 and 1.81), extent II TAAA repair (OR, 1.44 and 1.73), increasing age (OR, 1.04/year and 1.04/year), and increasing aortic cross-clamp time (OR, 1.02/minutes and 1.02/minutes). Patients with chronic dissection had lower 10-year unadjusted mortality (42% vs 69%) but more frequent repair failure (5% vs 3%) and subsequent repair for progressive aortic disease (11% vs 5%) than patients with non-dissection aneurysm (P < .001); these differences were no longer statistically significant after adjustment. CONCLUSIONS: Outcomes of open TAAA repair vary by aortic disease type. Emergency repairs and atherosclerotic diseases most commonly occur in patients with non-dissection aneurysm and independently predict operative mortality. Repair of chronic dissection is associated with low rates of adverse events, including operative mortality and persistent paraplegia, along with reasonable late survival and good durability. However, patients with chronic dissection tend to more commonly undergo subsequent repair to treat progressive aortic disease, which emphasizes the need for robust long-term imaging surveillance protocols.

From Surgical to Total Transcatheter Stage I Palliation: Exploring Evidence and Perspectives.

Neonates with single ventricle physiology and ductal-dependent systemic circulation, such as those with hypoplastic left heart syndrome, undergo palliation in the first days of life. Over the past decades, variations on the traditional Stage 1 palliation, also known as Norwood operation, have emerged. These include the hybrid palliation and the total transcatheter approach. Here, we review the current evidence and data on different Stage 1 approaches, with a focus on their advantages, challenges, and future perspectives. Overall, although controversy remains regarding the superiority or inferiority of one approach to another, outcomes after the Norwood and the hybrid palliation have improved over time. However, both procedures still represent high-risk approaches that entail exposure to sternotomy, surgery, and potential cardiopulmonary bypass. The total transcatheter Stage 1 palliation spares patients the surgical and cardiopulmonary bypass insults and has proven to be an effective strategy to bridge even high-risk infants to a later palliative surgery, complete repair, or transplant. As the most recently proposed approach, data are still limited but promising. Future studies will be needed to better define the advantages, challenges, outcomes, and overall potential of this novel approach.

Readmissions After Surgical Aortic Valve Replacement: Influence of Prosthesis Type.

INTRODUCTION: Prosthesis choice during aortic valve replacement (AVR) weighs lifelong anticoagulation with mechanical valves (M-AVR) against structural valve degeneration in bioprosthetic valves (B-AVR). METHODS: The Nationwide Readmissions Database was queried to identify patients who underwent isolated surgical AVR between January 1, 2016 and December 31, 2018, stratifying by prothesis type. Propensity score matching was used to compare risk-adjusted outcomes. Readmission at 1 y was estimated with Kaplan-Meier (KM) analysis. RESULTS: Patients (n = 109,744) who underwent AVR (90,574 B-AVR and 19,170 M-AVR) were included. B-AVR patients were older (median 68 versus 57 y; P < 0.001) and had more comorbidities (mean Elixhauser score: 11.8 versus 10.7; P < 0.001) compared to M-AVR patients. After matching (n = 36,951), there was no difference in age (58 versus 57 y; P = 0.6) and Elixhauser score (11.0 versus 10.8; P = 0.3). B-AVR patients had similar in-hospital mortality (2.3% versus 2.3%; P = 0.9) and cost (mean: $50,958 versus $51,200; P = 0.4) compared with M-AVR patients. However, B-AVR patients had shorter length of stay (8.3 versus 8.7 d; P < 0.001) and fewer readmissions at 30 d (10.3% versus 12.6%; P < 0.001) and 90 d (14.8% versus 17.8%; P < 0.001), and 1 y (P < 0.001, KM analysis). Patients undergoing B-AVR were less likely to be readmitted for bleeding or coagulopathy (5.7% versus 9.9%; P < 0.001) and effusions (9.1% versus 11.9%; P < 0.001). CONCLUSIONS: B-AVR patients had similar early outcomes compared to M-AVR patients, but lower rates of readmission. Bleeding, coagulopathy, and effusions are drivers of excess readmissions in M-AVR patients. Readmission reduction strategies targeting bleeding and improved anticoagulation management are warranted in the first year following AVR.

Mid-Term Efficacy of Subxiphoid Versus Transpleural Pericardial Window for Pericardial Effusion.

BACKGROUND: The optimal surgical technique for drainage of pericardial effusions is frequently debated. Transpleural drainage via thoracotomy or thoracoscopy is hypothesized to provide more durable freedom from recurrent pericardial effusion than a subxiphoid pericardial window. We sought to compare operative outcomes and mid-term freedom from recurrent effusion between both approaches in patients with nontraumatic pericardial effusions. METHODS: All patients at our institution who underwent a pericardial window from 2001 to 2018 were identified. After excluding those who underwent recent cardiothoracic surgery or trauma, patients (n = 46) were stratified by surgical approach and presence of malignancy. Primary outcome was freedom from recurrent moderate or greater pericardial effusion. Secondary outcomes included operative mortality and morbidity and mid-term survival. Follow-up was determined by medical record review, with a follow-up of 67 patient-years. Fisher's exact test and Wilcoxon rank-sum test were used to compare groups. Mid-term survival and freedom from effusion recurrence were determined using Kaplan-Meier method. RESULTS: Subxiphoid windows (n = 31; 67%) were more frequently performed than transpleural windows (n = 15; 33%) and baseline characteristics were similar. Effusion etiologies included malignancy (n = 22; 48%), idiopathic (n = 12; 26%), uremia (n = 8; 17%), and collagen vascular disease (n = 4; 9%). Perioperative outcomes were comparable between the two surgical approaches, except for longer drain duration (7 versus 4 d, P = 0.029) in the subxiphoid group. Operative mortality was 19.6% overall and 36.4% in patients with malignancy. Mid-term survival and freedom from moderate or greater pericardial effusion recurrence was 37% (95% confidence interval [CI]: 19%-54%) and 69% (95% CI: 52%-86%) at 5 y, respectively. There was no difference in mid-term survival (P = 0.90) or freedom from pericardial effusion recurrence (P = 0.70) between surgical approaches. Although malignant etiology had worse late survival (P < 0.01), freedom from effusion recurrence was similar to nonmalignant etiology (P = 0.70). CONCLUSIONS: Pericardial window provides effective mid-term relief of pericardial effusion. Subxiphoid and transpleural windows are equivalent in mid-term efficacy and both surgical approaches can be considered. Patients with malignancy have acceptable operative mortality with low incidence of recurrent effusion, supporting palliative indications.

Endovascular management of inferior vena cava filter thrombotic occlusion.

Objective Inferior vena cava occlusion is a potentially life-threatening complication related to caval filters. We present our experience with filter-induced inferior vena cava occlusion in order to assess the feasibility, safety, and effectiveness of endovascular management. Methods A retrospective review of all patients undergoing inferior vena cava filter placement over a 60-month study period was performed. From this cohort, a total of 10 cases of inferior vena cava occlusion after filter placement were identified. Demographics, clinical data, procedures, and outcomes were extracted. Patients were followed to the last clinic visit or until they died. Results One-hundred eighty filters were placed by our group practice during the study period. Of those, a total of 10 patients were identified. Overall, there were 7 males; the mean age was 57.1 years (25-78 years). The median time between inferior vena cava filter placement and filter occlusion was 105 days (range 5-4745 days). All patients were clinically symptomatic at the time of their presentation. Nine out of 10 patients were successfully managed endovascularly. Trellis™-8 thrombectomy was the most common endovascular strategy performed ( n = 9). Four patients had balloon angioplasty, two of those with stent placement for chronically occluded inferior vena cava/iliac veins. No thromboembolic complications developed during a median follow-up period of 233 days (range 4-1083 days). Conclusions Endovascular management of inferior vena cava occlusion is feasible, safe, and effective in decreasing thrombus burden in the presence of an inferior vena cava filter. Further studies evaluating long-term inferior vena cava patency and optimal surveillance regimen after endovascular management of filter-related inferior vena cava occlusion are warranted.

Cervical left aortic arch with distal tortuosity causing coarctation and aneurysmal formation in a child.

We present a case of a 10-year-old female with a cervical aortic arch and distal transverse arch tortuosity causing coarctation and aneurysmal formation and describe the surgical repair of this rare congenital anomaly.

Acute humoral rejection in an infant without risk factors after heart transplantation.

Graft rejection is the most common factor that limits graft survival after transplantation. During infancy, the humoral immune system is partially suppressed and humoral rejection of a cardiac allograft has not been reported in the absence of risk factors such as prior transplantation, blood transfusions, ventricular assist devices, and elevation of panel reactive antibodies. We present a case of an infant with dilated cardiomyopathy who developed multiple episodes of acute humoral rejection after heart transplantation in the absence of risk factors.

Outcomes After Extent I Thoracoabdominal Aortic Repair: Focus on Heritable Aortic Disease.

BACKGROUND: Crawford extent I thoracoabdominal aortic aneurysm (TAAA) repairs are increasingly performed by an endovascular approach, including in patients with heritable thoracic aortic disease (HTAD). We evaluated outcomes after open extent I TAAA repair in patients with and without HTAD. METHODS: This retrospective study included 992 patients (median age, 67 years; quartile 1-quartile 3, 57-73 years) who underwent extent I TAAA (1990-2022), stratified by the presence of HTAD (n = 177 [17.8%]). Patients with HTAD had genetic aortopathies or presented at age ≤50 years, and 35% (62 of 177) had Marfan syndrome. Logistic regression was used to identify predictors of operative death and adverse event, a composite of operative death and persistent (present at discharge) stroke, paraplegia, paraparesis, and renal failure necessitating dialysis. Long-term outcomes were analyzed with competing risks analysis. RESULTS: Patients with HTAD had lower rates of operative mortality (1.7% vs 7.0%, P = .01) and composite adverse event (2.8% vs 12.3%, P < .001) than non-HTAD patients. Most HTAD patients were discharged home (92.6% vs 76.9%, P < .001). Predictors of operative death were increasing age, aortic dissection, tobacco use, chronic symptoms, and rupture. Predictors for adverse event were increasing age, acute symptoms, chronic dissection, and rupture. Patients with HTAD had substantially better repair-failure-free survival (P < .001). CONCLUSIONS: Open extent I TAAA repair was effective in patients with HTAD, with low operative mortality and adverse event rates, better late survival, and excellent long-term durability, making a compelling argument for preferring open repair in these patients.

Contemporary Midterm Outcomes After Primary Repair of Chronic Type A Aortic Dissection.

BACKGROUND: Without surgical repair, acute type A aortic dissection (TAAD) is usually fatal. However, some patients survive without an early operation and progress to the chronic phase. Contemporary outcomes of primary surgical repair of chronic TAAD are unclear, so we evaluated them at our single-practice service. METHODS: During 1990 to 2021, 205 patients underwent repair of TAAD in the chronic phase (>60 days after onset). The 2 relevant DeBakey classifications were nearly equally represented: type I, 52% (n = 107), and type II, 48% (n = 98). The median interval between dissection onset and repair was 7 months (interquartile range, 3-25 months). Kaplan-Meier and competing-risk analyses provided time-dependent outcomes. RESULTS: At the time of intervention, most patients (40%) had chronic symptoms. Type I patients were younger than type II patients; however, comorbidities were similar. Most patients (n = 183 [87%]) underwent hemiarch or total arch repair, although total arch replacement was more common in type I dissection (P < .001). There were 15 operative deaths (7%), and 7 strokes (3%) persisted to the time of death or discharge. No patient had persistent paraplegia. Median follow-up was 5 years (interquartile range, 2-11 years). The 5-year reoperation-free survival was 61% (95% CI, 54%-68%), and the incidence of reoperation was 3% (95% CI, 0.4%-5%). Patients with type I and type II dissection did not differ significantly in survival (P = .2). CONCLUSIONS: Durable repair can be achieved with reasonable operative risk. Treatment is individualized and is associated with low rates of persistent neurologic complications. Despite differing operative approaches by DeBakey type, early and late outcomes were similar.

Racial/ethnic differences persist in treatment choice and outcomes in isolated intervention for coronary artery disease.

OBJECTIVE: Studies have noted racial/ethnic disparities in coronary artery disease intervention strategies. We investigated trends and outcomes of coronary artery disease treatment choice (coronary artery bypass grafting or percutaneous coronary intervention) stratified by race/ethnicity. METHODS: We queried the National Inpatient Sample for patients who underwent isolated coronary artery bypass grafting or percutaneous coronary intervention (2002-2017). Outcomes were stratified by race/ethnicity (White, African American, Hispanic, Asian). Multivariable logistic regression evaluated associations between race/ethnicity and receiving coronary artery bypass grafting versus percutaneous coronary intervention, in-hospital mortality, and costs. RESULTS: Over the 15-year period, 2,426,917 isolated coronary artery bypass grafting surgeries and 7,184,515 percutaneous coronary interventions were performed. Compared with White patients, African American patients were younger (62 [interquartile range, 53-70] vs 66 [interquartile range, 57-75] years), were more likely to have Medicaid insurance (12.2% vs 4.4%), and had more comorbidities (Charlson-Deyo index, 1.9 ± 1.6 vs 1.7 ± 1.6) (all P < .01). After adjustment for patient comorbidities, presence of acute myocardial infarction, insurance status, and geography, African Americans were the least likely of all racial/ethnic groups to undergo coronary artery bypass grafting (odds ratio, 0.76; P < .01), a consistent trend throughout the study. African American patients had higher risk-adjusted mortality after coronary artery bypass grafting (odds ratio, 1.09; P < .01). Race/ethnicity was not associated with increased mortality after percutaneous coronary intervention. African American patients had higher hospitalization costs for coronary artery bypass grafting (+$5816; P < .01) and percutaneous coronary intervention (+$856; P < .01) after controlling for confounders. CONCLUSIONS: In this contemporary national analysis, risk-adjusted frequency of coronary artery bypass grafting versus percutaneous coronary intervention for coronary artery disease differed by race/ethnicity. African American patients had lower odds of undergoing coronary artery bypass grafting and worse outcomes. Reasons for these differences merit further investigation to identify opportunities to reduce potential disparities.

Development of a Machine Learning Model to Predict Outcomes and Cost After Cardiac Surgery.

BACKGROUND: Machine learning (ML) algorithms may enhance outcomes prediction and help guide clinical decision making. This study aimed to develop and validate a ML model that predicts postoperative outcomes and costs after cardiac surgery. METHODS: The Society of Thoracic Surgeons registry data from 4874 patients who underwent cardiac surgery (56% coronary artery bypass grafting, 42% valve surgery, 19% aortic surgery) at our institution were divided into training (80%) and testing (20%) datasets. The Extreme Gradient Boosting decision-tree ML algorithms were trained to predict three outcomes: operative mortality, major morbidity or mortality, and Medicare outlier high hospitalization cost. Algorithm performance was determined using accuracy, F1 score, and area under the precision-recall curve (AUC-PR). The ML algorithms were validated in index surgery cases with The Society of Thoracic Surgeons risk scores for mortality and major morbidities and with logistic regression and were then applied to nonindex cases. RESULTS: The ML algorithms with 25 input parameters predicted operative mortality (accuracy 95%; F1 0.31; AUC-PR 0.21), major morbidity or mortality (accuracy 71%, F1 0.47; AUC-PR 0.47), and high cost (accuracy 84%; F1 0.62; AUC-PR 0.65). Preoperative creatinine, complete blood count, patient height and weight, ventricular function, and liver dysfunction were important predictors for all outcomes. For patients undergoing nonindex cardiac operations, the ML model achieved an AUC-PR of 0.15 (95% CI, 0.05-0.32) for mortality and 0.59 (95% CI, 0.51-0.68) for major morbidity or mortality. CONCLUSIONS: The extreme gradient boosting ML algorithms can predict mortality, major morbidity, and high cost after cardiac surgery, including operations without established risk models. These ML algorithms may refine risk prediction after cardiac surgery for a wide range of procedures.

Coronary artery bypass grafting at safety-net versus non-safety-net hospitals.

Objectives: Safety-net hospitals (SNHs) provide essential services to predominantly underserved patients regardless of their ability to pay. We hypothesized that patients who underwent coronary artery bypass grafting (CABG) would have inferior observed outcomes at SNHs compared with non-SNHs but that matched cohorts would have comparable outcomes. Methods: We queried the Nationwide Readmissions Database for patients who underwent isolated CABG from 2016 to 2018. We ranked hospitals by the percentage of all admissions in which the patient was uninsured or insured with Medicaid; hospitals in the top quartile were designated as SNHs. We used propensity-score matching to mitigate the effect of confounding factors and compare outcomes between SNHs and non-SNHs. Results: A total of 525,179 patients underwent CABG, including 96,133 (18.3%) at SNHs, who had a greater burden of baseline comorbidities (median Elixhauser score 8 vs 7; P = .04) and more frequently required urgent surgery (57.1% vs 52.8%; P < .001). Observed in-hospital mortality (2.1% vs 1.8%; P = .004) and major morbidity, length of stay (9 vs 8 days; P < .001), cost ($46,999 vs $38,417; P < .001), and readmission rate at 30 (12.4% vs 11.3%) and 90 days (19.0% vs 17.7%) were greater at SNHs (both P < .001). After matching, none of these differences persisted except length of stay (9 vs 8 days) and cost ($46,977 vs $39,343) (both P < .001). Conclusions: After matching, early outcomes after CABG were comparable at SNHs and non-SNHs. Improved discharge resources could reduce length of stay and curtail cost, improving the value of CABG at SNHs.

Ninety-Day Readmission After Open Surgical Repair of Stanford Type A Aortic Dissection.

BACKGROUND: Investigations into readmissions after surgical repair of acute Stanford type A aortic dissection (TAAD) remain scarce. We analyzed potential risk factors for readmission after TAAD. METHODS: The 2013 to 2014 US Nationwide Readmissions Database was queried for TAAD index hospitalizations and 90-day readmissions indicated by diagnostic and procedural codes. Multivariable analysis was completed to identify risk factors and the most common reasons for readmission. RESULTS: We identified 6975 patients (65% men; mean age, 60.0 ± 0.4 years) who underwent surgical repair for TAAD. Overall 2062 patients (29.6%) were readmitted within 90 days: 634 (30.7%) during the first 30 days and 1428 (69.3%) during days 31 through 90. Readmitted patients had a higher prevalence of chronic kidney disease at index admission (18.0% vs 11.6%, P = .002), greater overall index length of stay (17.8 ± 0.6 vs 15. 5 ± 0.4 days; P = .0003), and greater index hospitalization cost ($90,637 ± $2691 vs $80,082 ± $2091; P = .0003). Mortality during readmission was 3.6% (n = 74). Indications for readmission were most commonly cardiac (26.2%), infectious (17.8%), and pulmonary (11.7%). Multivariate analysis identified 2 independent risk factors for readmission: acute kidney injury (odds ratio, 1.49; 95% confidence interval, 1.24-1.78; P < .0001) and an Elixhauser comorbidity index > 4 (odds ratio, 1.26; 95% confidence interval, 1.06-1.49; P = .009). CONCLUSIONS: After surgical repair of TAAD, approximately 30% of patients were readmitted within 90 days, two-thirds of them during the 31- to 90-day period. Targeted improvements in perioperative care and postdischarge follow-up of patients with multiple comorbidities could mitigate readmission rates. Efforts to reduce readmissions should be continued throughout the 90-day period.

Outcomes of Aortic Valve Replacement for Chronic Aortic Insufficiency: Analysis of the Society of Thoracic Surgeons Database.

BACKGROUND: This study evaluated outcomes and risk factors for surgical aortic valve replacement (SAVR) for aortic insufficiency (AI) in a national cohort. We analyzed the incidence, outcomes, and risk factors for SAVR for AI in the Society of Thoracic Surgeons Adult Cardiac Surgery Database. METHODS: The national database was queried for patients with moderate or greater AI undergoing isolated SAVR between July 2011 and December 2018. Patients with moderate or greater aortic stenosis, acute dissection, active endocarditis, concomitant procedures, or emergent operation were excluded. AI was staged using guideline criteria based on symptoms and ventricular remodeling. Operative mortality and morbidity were compared between stages, and risk factors for operative death were identified. RESULTS: A total of 12,564 patients underwent isolated SAVR for AI from 2011 to 2018. Patients were most frequently AI stage D (7019 [57.5%]), compared with B (1405 [11.2%]), C1 (1128 [9.0%]), or C2 (1325 [10.5%]). Operative mortality was 1.1% overall, and increased between stage C1, C2, and D (0.4% vs 0.7% vs 1.6%, respectively, P < .01), along with major morbidity (5.1% vs 7.5% vs 9.9%, respectively; P < .01). Mortality was higher in patients with severe ventricular dilation and an ejection fraction of less than 0.30 (2.7% vs 1.0%, P < .01). Risk factors for death were symptomatic AI, decreased ejection fraction, age, weight, body surface area, and dialysis. CONCLUSIONS: Operative mortality and morbidity for isolated SAVR for AI is very low in a national cohort, providing a benchmark for future transcatheter approaches. Operative risk increases with advanced ventricular remodeling. SAVR before development of ventricular remodeling may be appropriate in patients with severe AI.

Readmission After Bioprosthetic vs Mechanical Mitral Valve Replacement in the United States.

BACKGROUND: Choosing between a bioprosthetic and a mechanical mitral valve is an important decision for both patients and surgeons. We compared patient outcomes and readmission rates after bioprosthetic mitral valve replacement (Bio-MVR) vs mechanical mitral valve replacement (Mech-MVR). METHODS: The Nationwide Readmissions Database was queried to identify 31 474 patients who underwent isolated MVR (22 998 Bio-MVR, 8476 Mech-MVR) between January 1, 2016, and December 31, 2018. Propensity score matching by age, sex, elective status, and comorbidities was used to compare outcomes between matched cohorts by prosthesis type. Freedom from readmission within the first calendar year was estimated by Kaplan-Meier analysis and compared between matched cohorts. RESULTS: Bio-MVR patients were older (median age, 69 vs 57 years; P < .001) and had more comorbidities (median Elixhauser score, 14 vs 11; P < .001) compared with Mech-MVR patients. After propensity score matching (n = 15 549), Bio-MVR patients had similar operative mortality (3.5% vs 3.4%; P = .97) and costs ($50 958 vs $49 782; P = .16) but shorter lengths of stay (8 vs 9 days; P < .001) and fewer 30-day (16.0% vs 18.1%; P = .04) and 90-day (23.8% vs 26.8%; P = .01) readmissions compared with Mech-MVR patients. The difference in readmissions persisted at 1 year (P = .045). Readmission for bleeding or coagulopathy complications was less common with Bio-MVR (5.7% vs 10.1%; P < .001). CONCLUSIONS: Readmission was more common after Mech-MVR than after Bio-MVR. Identifying and closely observing patients at high risk for bleeding complications may bridge the readmissions gap between Bio-MVR and Mech-MVR.

Outcomes, Cost, and Readmission After Surgical Aortic or Mitral Valve Replacement at Safety-Net and Non-Safety-Net Hospitals.

BACKGROUND: Safety-net hospitals provide essential services to vulnerable patients with complex medical and socioeconomic circumstances. We hypothesized that matched patients at safety-net hospitals and non-safety-net hospitals would have comparable outcomes, costs, and readmission rates after isolated surgical aortic valve replacement (AVR) or mitral valve replacement (MVR). METHODS: The National Readmissions Database was queried to identify patients who underwent isolated AVR (n = 109 744) or MVR (n = 31 475) from 2016 to 2018. Safety-net burden was defined as the percentage of patients who were uninsured or insured with Medicaid, with hospitals in the top quartile designated as safety-net hospitals. After propensity score matching, outcomes for AVR and MVR at safety-net hospitals vs non-safety-net hospitals were compared. RESULTS: Overall, 17 925 AVRs (16%) and 5516 MVRs (18%) were performed at safety-net hospitals, and these patients had higher comorbidity rates, had lower socioeconomic status, and more frequently required urgent surgery. Observed inhospital mortality was similar between safety-net hospitals and non-safety-net hospitals (AVR 2.2% vs 2.1%, P = .4; MVR 4.8% vs 4.3%, P = .1). After matching, rates of inhospital mortality, major morbidity, and readmission were similar; however, safety-net hospitals had longer length of stay after AVR (7 vs 6 days, P = .001) and higher total cost after AVR ($49 015 vs $42 473, P < .001) and MVR ($59 253 vs $52 392, P < .001). CONCLUSIONS: Isolated surgical AVR and MVR are both performed at safety-net hospitals with outcomes comparable to those at non-safety-net hospitals, supporting efforts to expand access to these procedures for underserved populations. Investment in care coordination resources to reduce length of stay and curtail cost at safety-net hospitals is warranted.

Machine Learning to Predict Outcomes and Cost by Phase of Care After Coronary Artery Bypass Grafting.

BACKGROUND: Machine learning may enhance prediction of outcomes after coronary artery bypass grafting (CABG). We sought to develop and validate a dynamic machine learning model to predict CABG outcomes at clinically relevant pre- and postoperative time points. METHODS: The Society of Thoracic Surgeons (STS) registry data elements from 2086 isolated CABG patients were divided into training and testing datasets and input into Extreme Gradient Boosting decision-tree machine learning algorithms. Two prediction models were developed based on data from preoperative (80 parameters) and postoperative (125 parameters) phases of care. Outcomes included operative mortality, major morbidity or mortality, high cost, and 30-day readmission. Machine learning and STS model performance were assessed using accuracy and the area under the precision-recall curve (AUC-PR). RESULTS: Preoperative machine learning models predicted mortality (accuracy, 98%; AUC-PR = 0.16; F1 = 0.24), major morbidity or mortality (accuracy, 75%; AUC-PR = 0.33; F1 = 0.42), high cost (accuracy, 83%; AUC-PR = 0.51; F1 = 0.52), and 30-day readmission (accuracy, 70%; AUC-PR = 0.47; F1 = 0.49) with high accuracy. Preoperative machine learning models performed similarly to the STS for prediction of mortality (STS AUC-PR = 0.11; P = .409) and outperformed STS for prediction of mortality or major morbidity (STS AUC-PR = 0.28; P < .001). Addition of intraoperative parameters further improved machine learning model performance for major morbidity or mortality (AUC-PR = 0.39; P < .01) and high cost (AUC-PR = 0.64; P < .01), with cross-clamp and bypass times emerging as important additive predictive parameters. CONCLUSIONS: Machine learning can predict mortality, major morbidity, high cost, and readmission after isolated CABG. Prediction based on the phase of care allows for dynamic risk assessment through the hospital course, which may benefit quality assessment and clinical decision-making.

Nationwide database analysis of one-year readmission rates after open surgical or thoracic endovascular repair of Stanford Type B aortic dissection.

Objective: We examined readmissions and resource use during the first postoperative year in patients who underwent thoracic endovascular aortic repair or open surgical repair of Stanford type B aortic dissection. Methods: The Nationwide Readmissions Database (2016-2018) was queried for patients with type B aortic dissection who underwent thoracic endovascular aortic repair or open surgical repair. The primary outcome was readmission during the first postoperative year. Secondary outcomes included 30-day and 90-day readmission rates, in-hospital mortality, length of stay, and cost. A Cox proportional hazards model was used to determine risk factors for readmission. Results: During the study period, type B aortic dissection repair was performed in 6456 patients, of whom 3517 (54.5%) underwent thoracic endovascular aortic repair and 2939 (45.5%) underwent open surgical repair. Patients undergoing thoracic endovascular aortic repair were older (63 vs 59 years; P < .001) with fewer comorbidities (Elixhauser score of 11 vs 17; P < .001) than patients undergoing open surgical repair. Thoracic endovascular aortic repair was performed electively more often than open surgical repair (29% vs 20%; P < .001). In-hospital mortality was 9% overall and lower in the thoracic endovascular aortic repair cohort than in the open surgical repair cohort (5% vs 13%; P < .001). However, the 90-day readmission rate was comparable between the thoracic endovascular aortic repair and open surgical repair cohorts (28% vs 27%; P = .7). Freedom from readmission for up to 1 year was also similar between cohorts (P = .6). Independent predictors of 1-year readmission included length of stay more than 10 days (P = .005) and Elixhauser comorbidity risk index greater than 4 (P = .033). Conclusions: Approximately one-third of all patients with type B aortic dissection were readmitted within 90 days after aortic intervention. Surprisingly, readmission during the first postoperative year was similar in the open surgical repair and thoracic endovascular aortic repair cohorts, despite marked differences in preoperative patient characteristics and interventions.

Development of a Risk Score to Predict 90-Day Readmission After Coronary Artery Bypass Graft.

BACKGROUND: Readmission after coronary artery bypass grafting (CABG) is used for quality metrics and may negatively affect hospital reimbursement. Our objective was to develop a risk score system from a national cohort that can predict 90-day readmission risk for CABG patients. METHODS: Using the National Readmission Database between 2013 and 2014, we identified 104,930 patients discharged after CABG, for a total of 234,483 patients after weighted analysis. Using structured random sampling, patients were divided into a training set (60%) and test data set (40%). In the training data set, we used multivariable analysis to identify risk factors. A point system risk score was developed based on the odds ratios. Variables with odds ratio less than 1.3 were excluded from the final model to reduce noise. Performance was assessed in the test data set using receiver operator characteristics and accuracy. RESULTS: In the United States, overall 90-day readmission rate after CABG was 19% (n = 44,559 of 234,483). Nine demographic and clinical variables were identified as important in the training data set. The final risk score ranged from 0 to 52; the 2 largest risks were associated with length of stay greater than 10 days (score = +10) and Medicaid insurance (score = +7). The final model's C-statistic was 0.67. Using an optimal cutoff of 18 points, the accuracy of the risk score was 77%. CONCLUSIONS: Ninety-day readmission after CABG surgery is frequent. A readmission risk score higher than 18 points predicts readmission in 77% of patients. Based on 9 demographic and clinical factors, this risk score can be used to target high-risk patients for additional postdischarge resources to reduce readmission.

Primary Aortic Root Replacement Outcomes and Risk Factors in Pediatric Patients.

BACKGROUND: The study sought to identify the optimal aortic root replacement (ARR) strategy for pediatric patients, and a single-center experience was analyzed. METHODS: Retrospective review of patients undergoing ARR from 1995 to 2018 was performed. Patients were stratified by surgical strategy (pulmonary autograft [Ross procedure], aortic homograft, mechanical valve conduit [Bentall procedure], or porcine xenograft [Freestyle bioprosthesis]) and aortic annulus size. RESULTS: ARR was performed in 206 patients with a median follow-up of 5.0 (interquartile range, 1.4-11.4) years. Root replacements included Ross procedure (n = 98), homograft (n = 83), Bentall procedure (n = 18), and Freestyle bioprosthesis (n = 7). Overall survival was 92%, and freedom from reoperation or death was 81%. Reoperation-free survival was superior in the Ross group when compared with other groups. Because surgical options differ based on the size of the aortic annulus, the analysis was arbitrarily stratified. When the aortic annulus diameter was greater than 19 mm (n = 74), procedures included Ross procedure (n = 23), homograft (n = 29), Bentall procedure (n = 17), and Freestyle bioprosthesis (n = 5). Reoperation-free survival at median follow-up (5 years) was 86%, 58%, 100%, and 100%, respectively. The Bentall procedure offered the longest freedom from reoperation. In the subset with aortic annulus diameter less than 19 mm and a pulmonary valve suitable for a Ross procedure, patients underwent the Ross procedure (n = 75) or homograft ARR (n = 36). At median follow-up (3.8 years), reoperation-free survival was longer after the Ross procedure than after homograft ARR (88% vs 46%; P < .001). CONCLUSIONS: In patients with a large aortic annulus, a Bentall ARR offers the longest reoperation-free survival. For patients with small aortic roots, a Ross procedure provides better a reoperation-free survival than does homograft ARR.