Incidence, characteristics, and outcomes of reintervention after mitral transcatheter edge-to-edge repair.

OBJECTIVE: The use of transcatheter edge-to-edge repair (TEER) is growing substantially, and reintervention after TEER by way of repeat TEER or mitral valve surgery (MVS) is increasing as a result. In this nationally representative study we examined the incidence, characteristics, and outcomes of reintervention after index TEER. METHODS: Between July 2013 and November 2017, we reviewed 11,396 patients who underwent index TEER using Medicare beneficiary data. These patients were prospectively tracked and identified as having repeat TEER or MVS. Primary outcomes included 30-day mortality, 30-day readmission, 30-day composite morbidity, and cumulative survival. RESULTS: Among 11,396 patients who underwent TEER, 548 patients (4.8%) required reintervention after a median time interval of 4.5 months. Overall 30-day mortality was 8.6%, 30-day readmission was 20.9%, and 30-day composite morbidity was 48.2%. According to reintervention type, 294 (53.7%) patients underwent repeat TEER, and 254 (46.3%) underwent MVS. Patients who underwent MVS were more likely to be younger and female, but had a similar comorbidity burden compared with the repeat TEER cohort. After adjustment, there were no differences in 30-day mortality (adjusted odds ratio [AOR], 1.26 [95% CI, 0.65-2.45]) or 30-day readmission (AOR, 1.14 [95% CI, 0.72-1.81]). MVS was associated with higher 30-day morbidity (AOR, 4.76 [95% CI, 3.17-7.14]) compared with repeat TEER. Requirement for reintervention was an independent risk factor for long-term mortality in a Cox proportional hazard model (hazard ratio, 3.26 [95% CI, 2.53-4.20]). CONCLUSIONS: Reintervention after index TEER is a high-risk procedure that carries a significant mortality burden. This highlights the importance of ensuring procedural success for index TEER to avoid the morbidity of reintervention altogether.

Skeletonized versus Pedicled harvesting of internal mammary artery: A systematic review and Meta-analysis.

There are two recognized internal mammary artery (IMA) harvesting techniques during coronary artery bypass grafting (CABG): pedicled and skeletonized. This systematic review and meta-analysis sought to compare the clinical outcomes of the two harvesting techniques. A comprehensive electronic literature search of PubMed, Scopus, and Embase was conducted from inception till June 2023. Thirty-one studies with a total of 13005 patients met our inclusion criteria. The results from the included studies were presented as weighted mean difference (WMD) with its relevant standard deviation (SD) for continuous variables, while Odds Ratio (OR) was used for dichotomous variables. A 95% confidence interval (CI) was used, and the results were pooled using a random effects model. The skeletonized IMA demonstrated a significantly reduced risk of sternal wound infection (SWI) compared to the pedicled IMA (OR = 0.45 [95% CI, 0.32-0.66]; p = 0.0001). The conduit length used was significantly longer in the skeletonized IMA (WMD -2.48, 95% CI, [-3.75, -1.20], P = 0.0001) and a significantly higher postoperative flow rate was observed while using skeletonization compared to the pedicled harvesting (WMD -13.11, 95% CI, [-22.52, -3.70], P = 0.006). However, no significant difference was seen in mortality between the two techniques (OR = 1.19 [95% CI, 1.00-1.41]; p = 0.05). Pedicled harvesting demonstrated significantly reduced incidents of MI (OR = 1.38 [95% CI, 1.13-1.69]; p = 0.002), while significant results in graft patency were observed favoring pedicled harvesting over skeletonization (OR = 0.63 [95% CI, 0.40-0.98]; p = 0.04).

Predictors of outcomes in patients with obesity following mitral valve surgery.

Objective: Few studies have assessed the outcomes of mitral valve surgery in patients with obesity. We sought to study factors that determine the in-hospital outcomes of this population to help clinicians provide optimal care. Methods: A retrospective analysis of adult patients with obesity who underwent open mitral valve replacement or repair between January 1, 2012, and December 31, 2020, was conducted using the National Inpatient Sample. Weighted logistic regression and random forest analyses were performed to assess factors associated with mortality and the interaction of each variable. Results: Of the 48,775 patients with obesity, 34% had morbid obesity (body mass index ≥40), 55% were women, 66% underwent elective surgery, and 55% received isolated open mitral valve replacement or repair. In-hospital mortality was 5.0% (n = 2430). After adjusting for important covariates, a greater risk of mortality was associated with older patients (adjusted odds ratio [aOR], 1.24; 95% CI, 1.08-1.43), higher Elixhauser comorbidity score (aOR, 2.10; 95% CI, 1.87-2.36), prior valve surgery (aOR, 1.63; 95% CI, 1.01-2.63), and more than 2 concomitant procedures (aOR, 2.83; 95% CI, 2.07-3.85). Lower mortality was associated with elective admissions (aOR, 0.70; 95% CI, 0.56-0.87) and valve repair (aOR, 0.58; 95% CI, 0.46-0.73). Machine learning identified several interactions associated with early mortality, such as Elixhauser score, female sex, body mass index ≥40, and kidney failure. Conclusions: The complexity of presentation, comorbidities in older and female patients, and morbid obesity are independently associated with an increased risk of mortality in patients undergoing open mitral valve replacement or repair. Morbid obesity and sex disparity should be recognized in this population, and physicians should consider older patients and females with multiple comorbidities for earlier and more opportune treatment windows.

Benchmarking Outcomes of Surgical Aortic Valve Replacement in Patients With Bicuspid Aortic Valves.

BACKGROUND: The relative roles for transcatheter and surgical aortic valve replacement (SAVR) for bicuspid aortic valve (AV) stenosis are debated. This study analyzes the 5-year longitudinal outcomes of isolated SAVR in bicuspid vs tricuspid AV patients, particularly in low-risk patients. METHODS: All patients undergoing isolated index SAVR at 1146 United States hospitals in The Society of Thoracic Surgeons (STS) Adult Cardiac database between July 1, 2011, and December 31, 2018, with linkage to Medicare claims, were analyzed. RESULTS: A total of 65,687 patients were analyzed, including of 9131 bicuspid patients (13.9%). Compared with tricuspid patients, bicuspid patients were significantly younger (median 70 vs 74 years, P < .001) with lower Society of Thoracic Surgeons predicted risk of mortality scores (mean 1.6% vs 2.3%, P < .001) and lower risk profile. Risk-adjusted 30-day mortality and major morbidity were similar, but risk-adjusted 5-year mortality was significantly lower in the bicuspid patients (adjusted hazard ratio, 0.72; 95% CI, 0.66-0.77), specifically in low-risk patients (adjusted hazard ratio, 0.69; 95% CI, 0.64-0.76). Additionally, the bicuspid cohort had a lower 5-year readmission risk of heart failure, stroke, bleeding, or other cardiovascular causes (all P < .05). CONCLUSIONS: In this nationally representative study, 30-day mortality was similar, but risk-adjusted 5-year mortality was significantly lower in bicuspid patients undergoing isolated SAVR compared with tricuspid patients, specifically low-risk and normal left ventricular ejection fraction patients. This analysis provides a much-needed 5-year longitudinal national-level benchmark to better inform the discussion of transcatheter vs SAVR in bicuspid patients.

Comparison of Postdischarge Outcomes Between Valve-in-Valve Transcatheter Mitral Valve Replacement and Reoperative Surgical Mitral Valve Replacement.

Limited data are available comparing the postdischarge perioperative outcomes of isolated valve-in-valve transcatheter mitral valve replacement (VIV-TMVR) versus surgical reoperative mitral valve replacement (re-SMVR) on a nationwide scale. The objective of this study was to perform a robust head-to-head assessment of contemporary postdischarge outcomes between isolated VIV-TMVR and re-SMVR using a large national multicenter longitudinal database. Adult patients aged ≥18 years with failed/degenerated bioprosthetic mitral valves who underwent either isolated VIV-TMVR or re-SMVR were identified in the 2015 to 2019 Nationwide Readmissions Database. The risk-adjusted differences in 30-, 90-, and 180-day outcomes were compared using propensity score weighting with overlap weights to mimic the results of a randomized controlled trial. The differences between a transeptal and transapical VIV-TMVR approach were also compared. A total of 687 patients with VIV-TMVR and 2,047 patients with re-SMVR were included. After the overlap weighting to attain balance between treatment groups, VIV-TMVR was associated with significantly lower major morbidity within 30 (odds ratio [95% confidence interval (CI)] 0.0.31 [0.22 to 0.46]), 90 (0.34 [0.23 to 0.50]), and 180 (0.35 [0.24 to 0.51]) days. The differences in major morbidity were primarily driven by less major bleeding (0.20 [0.14 to 0.30]), new onset complete heart block (0.48 [0.28 to 0.84]) and need for permanent pacemaker placement (0.26 [0.12 to 0.55]). The differences in renal failure and stroke were not significant. VIV-TMVR was also associated with shorter index hospital stays (median difference [95% CI] -7.0 [4.9 to 9.1] days) and an increased ability for patients to be discharged home (odds ratio [95% CI] 3.35 [2.37 to 4.72]). There were no significant differences in total hospital costs; in-hospital or 30-, 90-, and 180-day mortality; or readmission. The findings remained similar when stratifying the VIV-TMVR access using a transeptal versus a transapical approach. The changes in outcomes over time suggest marked improvements for patients with VIV-TMVR relative to stagnant results for patients with re-SMVR from 2015 to 2019. In this large nationally representative cohort of patients with failed/degenerated bioprosthetic mitral valves, VIV-TMVR appears to confer a short-term advantage over re-SMVR in terms of morbidity, discharge home, and length of stay. It yielded equivalent outcomes for mortality and readmission. Longer-term studies are needed to assess further follow-up beyond 180 days.

Surgical Explantation of Failed Transcatheter Aortic Valve Replacement.

BACKGROUND: Recent reports have demonstrated worse than expected outcomes of surgical explantation after transcatheter aortic valve replacement (TAVR). However in-depth analysis of the short- and mid-term risk of concomitant cardiac surgery at the time of TAVR explant is lacking. METHODS: Data from the multicenter EXPLANT-TAVR registry of patients undergoing TAVR-explant between November 2009 and September 2020 were retrospectively analyzed. Patients undergoing concomitant procedures were included, but explants performed during the same admission as the initial TAVR or concomitant procedures performed on the aortic root, ascending aorta, or arch were excluded. Outcomes were evaluated between the isolated surgical aortic valve replacement (SAVR) and concomitant SAVR groups. Median follow-up was 6.6 months. RESULTS: Among 199 patients, concomitant SAVR was performed in 94 patients (47.2%), primarily with mitral valve surgery (n = 45) followed by coronary artery bypass grafting (n = 23). Despite similar mean ages between groups (72.8 vs 73.4 years), concomitant SAVR had a higher median Society of Thoracic Surgeons Predicted Risk of Mortality score at the index TAVR (5.9% vs 3.7%, P = .001). There were no differences in median time-to-explant between groups (12.9 vs 8.7 months, P = .78). However concomitant SAVR had longer mean cardiopulmonary bypass (166 vs 114 minutes, P = .001) and cross-clamp times (123 vs 81 minutes, P = .001). Both 30-day (16.7% vs 9.9%) and 1-year mortality (36.1% vs 22.1%) were higher with concomitant SAVR but did not reach statistical significance (both P > .05). On Kaplan-Meier analysis, actuarial estimates of cumulative survival were significantly lower with concomitant SAVR at 3 years (56.8% vs 81.1%, P = .020). CONCLUSIONS: For surgical explantation after TAVR failure, concomitant SAVR is associated with increased mortality. Further studies with longer follow-up are warranted to examine the benefit from earlier intervention before concomitant disease develops.

Operative Teaching of Coronary Bypass and Need for Repeat Catheterization: Does it Matter Who is Sewing?

OBJECTIVE: There are no studies to date comparing the patency of coronary bypass grafts constructed by attending surgeons versus trainees and the potential consequences of any such disparities. We explored this issue by comparing the patency of individual anastomoses performed by residents versus the attending surgeon. DESIGN: We reviewed 765 continuous cases performed by a single surgeon which involved at least 1 coronary bypass anastomosis, totaling 2,173 distal anastomoses. At a median follow-up time of 36 months (interquartile range 20.5-47.3), 83 (10.9%) patients had undergone 110 cardiac catheterization procedures after their original operation for various indications. This angiographic information provided the data for our comparison cohorts. SETTING: Cardiac surgery practice within an academic setting PARTICIPANTS: Adult patient undergoing coronary bypass grafting RESULTS: Of the 83 patients that underwent repeat catheterization, 23 (27.7%) were resident cases, 25 (30.1%) were attending cases and 35 (42.2%) were mixed. There were 4/83 (4.8%) patients with angiographic evidence of internal mammary artery graft compromise of which 3/4 (75%) had been constructed by the attending surgeon. Angiographic evidence of saphenous vein graft compromise was appreciated in 16/83 (19.3%) patients of which 9/16 (56.3%) of the grafts were constructed by the attending surgeon. CONCLUSIONS: Liberal involvement of surgical trainees as primary operators in coronary revascularization cases led to equivalent rates of postoperative ischemic complications between the attending and resident groups. The outcome equivalence was also maintained when evaluated at the individual anastomosis patency level between the 2 groups. We conclude that academic programs should continue providing trainees significant experience as primary operating surgeons without fear of clinical outcome compromise.

Reassessing the July Effect: 30 Years of Evidence Show No Difference in Outcomes.

OBJECTIVE: The aim of this study was to critically evaluate whether admission at the beginning versus end of the academic year is associated with increased risk of major adverse outcomes. SUMMARY BACKGROUND DATA: The hypothesis that the arrival of new residents and fellows is associated with increases in adverse patient outcomes has been the subject of numerous research studies since 1989. Methods: We conducted a systematic review and random-effects meta-analysis of July Effect studies published before December 20, 2019, looking for differences in mortality, major morbidity, and readmission. Given a paucity of studies reporting readmission, we further analyzed 7 years of data from the Nationwide Readmissions Database to assess for differences in 30-day readmission for US patients admitted to urban teaching versus nonteach-ing hospitals with 3 common medical (acute myocardial infarction, acute ischemic stroke, and pneumonia) and 4 surgical (elective coronary artery bypass graft surgery, elective colectomy, craniotomy, and hip fracture) conditions using risk-adjusted logistic difference-in-difference regression. RESULTS: A total of 113 studies met inclusion criteria; 92 (81.4%) reported no evidence of a July Effect. Among the remaining studies, results were mixed and commonly pointed toward system-level discrepancies in efficiency. Metaanalyses of mortality [odds ratio (95% confidence interval): 1.01 (0.98-1.05)] and major morbidity [1.01 (0.99-1.04)] demonstrated no evidence of a July Effect, no differences between specialties or countries, and no change in the effect over time. A total of 5.98 million patient encounters were assessed for readmission. No evidence of a July Effect on readmission was found for any of the 7 conditions. CONCLUSION: The preponderance of negative results over the past 30 years suggests that it might be time to reconsider the need for similarly-themed studies and instead focus on system-level factors to improve hospital efficiency and optimize patient outcomes.

Association Between Peripheral Versus Central Access for Alternative Access Transcatheter Aortic Valve Replacement and Mortality and Stroke: A Report From the Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry.

BACKGROUND: In some patients, the alternative access route for transcatheter aortic valve replacement (TAVR) is utilized because the conventional transfemoral approach is not felt to be either feasible or optimal. However, accurate prognostication of patient risks is not well established. This study examines the associations between peripheral (transsubclavian/transaxillary, and transcarotid) versus central access (transapical and transaortic) in alternative access TAVR and 30-day and 1-year end points of mortality and stroke for all valve platforms. METHODS: Using data from The Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry with linkage to Medicare claims, patients who underwent alternative access TAVR from June 1, 2015 to June 30, 2018 were identified. Adjusted and unadjusted Cox proportional hazards modeling were performed to determine the association between alternate access TAVR site and 30-day and 1-year end points of mortality and stroke. RESULTS: Of 7187 alternative access TAVR patients, 3725 (52%) had peripheral access and 3462 (48%) had central access. All-cause mortality was significantly lower in peripheral access versus central access group at in-hospital and 1 year (2.9% versus 6.3% and 20.3% versus 26.6%, respectively), but stroke rates were higher (5.0% versus 2.8% and 7.3% versus 5.5%, respectively; all P<0.001). These results persisted after 1-year adjustment (death adjusted hazard ratio, 0.72 [95% CI, 0.62-0.85] and stroke adjusted hazard ratio, 2.92 [95% CI, 2.21-3.85]). When broken down by individual subtypes, compared with transaxillary/subclavian access patients, transapical, and transaortic access patients had higher all-cause mortality but less stroke (P<0.05). CONCLUSIONS: In this real-world, contemporary, nationally representative benchmarking study of alternate access TAVR sites, peripheral access was associated with favorable mortality and morbidity outcomes compared with central access, at the expense of higher stroke. These findings may allow for accurate prognostication of risk for patient counseling and decision-making for the heart team with regard to alternative access TAVR.

Ninety-Day Risk-Standardized Home Time as a Performance Metric for Cardiac Surgery Hospitals in the United States.

BACKGROUND: Assessing hospital performance for cardiac surgery necessitates consistent and valid care quality metrics. The association of hospital-level risk-standardized home time for cardiac surgeries with other performance metrics such as mortality rate, readmission rate, and annual surgical volume has not been evaluated previously. METHODS: The study included Medicare beneficiaries who underwent isolated or concomitant coronary artery bypass graft, aortic valve, or mitral valve surgery from January 1, 2013, to October 1, 2019. Hospital-level performance metrics of annual surgical volume, 90-day risk-standardized mortality rate, 90-day risk-standardized readmission rate, and 90-day risk-standardized home time were estimated starting from the day of surgery using generalized linear mixed models with a random intercept for the hospital. Correlations between the performance metrics were assessed using the Pearson correlation coefficient. Patient-level clinical outcomes were also compared across hospital quartiles by 90-day risk-standardized home time. Last, the temporal stability of performance metrics for each hospital during the study years was also assessed. RESULTS: Overall, 919 698 patients (age 74.2±5.8 years, 32% women) were included from 1179 hospitals. Median 90-day risk-standardized home time was 71.2 days (25th-75th percentile, 66.5-75.6), 90-day risk-standardized readmission rate was 26.0% (19.5%-35.7%), and 90-day risk-standardized mortality rate was 6.0% (4.0%-8.8%). Across 90-day home time quartiles, a graded decline was observed in the rates of in-hospital, 90-day, and 1-year mortality, and 90-day and 1-year readmission. Ninety-day home time had a significant positive correlation with annual surgical volume (r=0.31; P<0.001) and inverse correlation with 90-day risk-standardized readmission rate (r=-0.40; P <0.001) and 90-day risk-standardized mortality rate (r=-0.60; P <0.001). Use of 90-day home time as a performance metric resulted in a meaningful reclassification in performance ranking of 22.8% hospitals compared with annual surgical volume, 11.6% compared with 90-day risk-standardized mortality rate, and 19.9% compared with 90-day risk-standardized readmission rate. Across the 7 years of the study period, 90-day home time demonstrated the most temporal stability of the hospital performance metrics. CONCLUSIONS: Ninety-day risk-standardized home time is a feasible, comprehensive, patient-centered metric to assess hospital-level performance in cardiac surgery with greater temporal stability than mortality and readmission measures.

Aortic root management in acute type A aortic dissection: A nationwide analysis.

OBJECTIVE: Acute type A aortic dissection (ATAAD) is a life-threatening condition and surgical repair often includes aortic valve replacement (AVR). Aortic valve repair (AVr) is increasingly being reported with favorable outcomes from single-center experiences. This study examined national trends and outcomes of AVr in patients with ATAAD. METHODS: Adults with a primary diagnosis of acute thoracic aortic dissection who underwent proximal aortic surgery from January 2016 to December 2017 were obtained from the National Inpatient Sample. Patients were stratified into an isolated aortic surgery group (no aortic valve procedure), concomitant AVR, or concomitant AVr groups. The primary outcome was in-hospital mortality and secondary outcomes included stroke, acute kidney injury, heart block, and bleeding. Propensity score matching was used to address patient and hospital-level confounders between AVR and AVr groups. RESULTS: In total, 5115 patients underwent surgery for ATAAD and were included. Overall, 3220 (63%) underwent isolated ATAAD repair, while 1120 (22%) had concomitant AVR, and 775 (15%) had concomitant AVr. In 455 propensity-matched pairs, there was no difference in mortality or stroke between AVr and AVR groups, however, heart block (1.1% vs. 7.5%, p < .001) and bleeding (65.9% vs. 81.3%, p < .001) were significantly less common among those who underwent AVr. Patients who underwent AVr had shortest LOS (11.9 vs. 13.5 days, p < .001). There were no differences in outcomes of AVr in ATAAD based on hospital size or teaching status. CONCLUSION: In selected patients, AVr is being performed safely in the setting of ATAAD with mortality and composite outcomes comparable to AVR.

Does the "July effect" of new trainees at teaching hospitals impact outcomes for patients hospitalized with heart failure? Real-world analyses of more than half a million US admissions.

Introduction: The "July effect" refers to the potential of adverse clinical outcomes related to the annual turnover of trainees. We investigated whether this impacts inpatient heart failure (HF) outcomes. Methods: Data from all adults (≥18 years) admitted with a primary diagnosis of HF at US teaching hospitals from the 2012-2014 National Inpatient Sample were analyzed. Non-teaching hospital admissions were excluded. The primary outcome was in-hospital mortality. Secondary metrics included hospital length of stay (LOS) and total cost adjusted for inflation. Logistic and linear regression models were used to adjust for confounders. Admissions were classified into 4 quarters (Q1-Q4), based on the academic calendar. Q1 and Q4 were designated to assess the effect of novice (July effect) versus experienced trainees, respectively. Results: There were 699,675 HF admissions during Q1 and Q4 in the study period. Mean age was 71 ± 15 years and 48% were females. There were 20,270 in-hospital deaths, with no difference between Q1 and Q4; crude odds ratio (OR) 1.00, 95% confidence interval (CI) 0.94-1.07, p = 0.95. After risk adjustment, there was no in-hospital mortality difference between Q1 and Q4 admissions; adjusted OR 0.96, 95% CI 0.89-1.03, p = 0.23. There was no difference in hospital LOS or total cost; 5.8 versus 5.8 days, p = 0.66 and $13,755 versus $13,586, p = 0.46, in Q1 and Q4, respectively. Conclusions: In this nationally representative sample, there was no evidence of a "July effect" on inpatient HF outcomes in the US. This suggests that HF patients should not delay seeking care during trainee transitions at teaching hospitals.

Defining Referral Regions for Inpatient Trauma Care: The Utility of a Novel Geographic Definition.

INTRODUCTION: Geographic variation is an inherent feature of the US health system. Despite efforts to account for geographic variation in trauma system strengthening, it remains unclear how trauma "regions" should be defined. The objective of this study is to evaluate the utility of a novel definition of Trauma Referral Regions (TRR) for assessing geographic variation in inpatient trauma across the age span of hospitalized trauma patients. METHODS: Using 2016-2017 State Inpatient Databases, we assessed the extent of geographic variability in three common metrics of hospital use (localization index, market share index, net patient flow) among TRRs and, as a comparison, trauma regions alternatively defined based on Hospital Referral Regions, Hospital Service Areas, and counties. RESULTS: A total of 860,593 admissions from 102 TRRs, 127 Hospital Referral Regions, 884 Hospital Service Areas, and 583 counties were included. Consistent with expectations for distinct trauma regions, TRR presented with high average localization indices (mean [standard deviation]: 83.4 [11.7%]), low market share indices (mean [standard deviation]: 11.9 [7.0%]), and net patient flows close to 1.00. Similar results were found among stratified pediatric, adult, and older adult patients. Associations between TRRs and variations in important demographic features (e.g., travel time by road to the nearest Level I or II Trauma Center) suggest that while indicative of standalone trauma regions, TRRs are also able to simultaneously capture critical variations in regional trauma care. CONCLUSIONS: TRRs offer a standalone set of geographic regions with minimal variation in common metrics of hospital use, minimal geographic clustering, and preserved associations with important demographic factors. They provide a needed, valid means of assessing geographic variation among trauma systems.

The impact of hospital size on national trends and outcomes in isolated open proximal aortic surgery.

OBJECTIVE: To determine the impact of hospital size on national trend estimates of isolated open proximal aortic surgery for benchmarking hospital performance. METHODS: Patients age >18 years who underwent isolated open proximal aortic surgery for aneurysm and dissection from 2002 to 2014 were identified using the National Inpatient Sample. Concomitant valvular, vessel revascularization, re-do procedures, endovascular, and surgery for descending and thoracoabdominal aorta were excluded. Discharges were stratified by hospital size and analyzed using trend, multivariable regression, propensity-score matching analysis. RESULTS: Over a 13-year period, 53,657 isolated open proximal aortic operations were performed nationally. Although the total number of operations/year increased (∼2.9%/year increase) and overall in-hospital mortality decreased (∼4%/year; both P < .001 for trend), these did not differ by hospital size (P > .05). Large hospitals treated more sicker and older patients but had shorter length of stay and lower hospital costs (both P < .001). Even after propensity-score matching, large hospital continued to demonstrate superior in-hospital outcomes, although only statistically for major in-hospital cardiac complications compared with non-large hospitals. In our subgroup analysis of dissection versus non-dissection cohort, in-hospital mortality trends decreased only in the non-dissection cohort (P < .01) versus dissection cohort (P = .39), driven primarily by the impact of large hospitals (P < .01). CONCLUSIONS: This study demonstrates increasing volume and improving outcomes of isolated open proximal aortic surgeries nationally over the last decade regardless of hospital bed size. Moreover, the resource allocation of sicker patients to larger hospital resulted shorter length of stay and hospital costs, while maintaining similar operative mortality to small- and medium-sized hospitals.