A Decade of Thoracic Endovascular Aortic Aneurysm Repair in New York State: Volumes, Outcomes, and Implications for the Dissemination of Endovascular Technology

Longitudinal outcomes of thoracic endovascular aortic repair for ruptured thoracic aortic aneurysms

BACKGROUND

Limited data exist on long-term mortality and reintervention rates after emergent thoracic endovascular aortic repair (TEVAR) for ruptured thoracic aortic aneurysm (rTAA). This study aimed to characterize the long-term outcomes of emergent TEVAR for rTAA.

METHODS

All TEVARs for rTAA and elective intact thoracic aortic aneurysms (iTAAs) were reviewed at a large academic medical center from 2005 to 2022. Long-term clinical outcomes were considered over eight years.

RESULTS

Of 321 patients undergoing TEVAR for TAA, 20% (65/321) presented with rTAA. Median clinical follow-up was 5.1 years. rTAA patients had much lower 30-day survival (69.2% vs 96.9%; P < .001) and higher rates of stroke, pneumonia, and prolonged ventilation (all P ≤ .01). Long-term survival was worse for all rTAA patients compared to all iTAA patients at 1 year (46% vs 86%), 5 years (27% vs 48%), and 8 years (20% vs 32%; all P < .001), driven largely by frequent early mortality. However, for patients surviving at least 90 days, the long-term survival difference over 8 years was minimal (34% vs 33%, log-rank P = .43) among patients presenting with ruptured vs intact TAA. Ruptured aneurysms required more reinterventions within 30 days, but had comparable late reintervention rates, with type I endoleak as the leading cause.

CONCLUSIONS

The present study is the largest to focus on long-term outcomes following TEVAR for rupture TAA. Unsuprisingly, short-term outcomes are worse in patients presenting with ruptured vs intact aneurysms. However, importantly, long-term survival in rTAA patients who do survive 90 days is comparable to that of iTAA patients.

Surgeon volume and outcomes following thoracic endovascular aortic repair for blunt thoracic aortic injury

OBJECTIVE

Thoracic endovascular aortic repair (TEVAR) for blunt thoracic aortic injury (BTAI) at high-volume hospitals has previously been associated with lower perioperative mortality, but the impact of annual surgeon volume on outcomes following TEVAR for BTAI remains unknown.

METHODS

We analyzed Vascular Quality Initiative (VQI) data from patients with BTAI that underwent TEVAR between 2013 and 2023. Annual surgeon volumes were computed as the number of TEVARs (for any pathology) performed over a 1-year period preceding each procedure and were further categorized into quintiles. Surgeons in the first volume quintile were categorized as low volume (LV), the highest quintile as high volume (HV), and the middle three quintiles as medium volume (MV). TEVAR procedures performed by surgeons with less than 1-year enrollment in the VQI were excluded. Using multilevel logistic regression models, we evaluated associations between surgeon volume and perioperative outcomes, accounting for annual center volumes and adjusting for potential confounders, including aortic injury grade and severity of coexisting injuries. Multilevel models accounted for the nested clustering of patients and surgeons within the same center. Sensitivity analysis excluding patients with grade IV BTAI was performed.

RESULTS

We studied 1321 patients who underwent TEVAR for BTAI (28% by LV surgeons [0-1 procedures per year], 52% by MV surgeons [2-8 procedures per year], 20% by HV surgeons [≥9 procedures per year]). With higher surgeon volume, TEVAR was delayed more (in <4 hours: LV: 68%, MV: 54%, HV: 46%; P < .001; elective (>24 hours): LV: 5.1%; MV: 8.9%: HV: 14%), heparin administered more (LV: 80%, MV: 81%, HV: 87%; P = .007), perioperative mortality appears lower (LV: 11%, MV: 7.3%, HV: 6.5%; P = .095), and ischemic/hemorrhagic stroke was lower (LV: 6.5%, MV: 3.6%, HV: 1.5%; P = .006). After adjustment, compared with LV surgeons, higher volume surgeons had lower odds of perioperative mortality (MV: 0.49; 95% confidence interval [CI], 0.25-0.97; P = .039; HV: 0.45; 95% CI, 0.16-1.22; P = .12; MV/HV: 0.50; 95% CI, 0.26-0.96; P = .038) and ischemic/hemorrhagic stroke (MV: 0.38; 95% CI, 0.18-0.81; P = .011; HV: 0.16; 95% CI, 0.04-0.61; P = .008). Sensitivity analysis found lower adjusted odds for perioperative mortality (although not significant) and ischemic/hemorrhagic stroke for higher volume surgeons.

CONCLUSIONS

In patients undergoing TEVAR for BTAI, higher surgeon volume is independently associated with lower perioperative mortality and postoperative stroke, regardless of hospital volume. Future studies could elucidate if TEVAR for non-ruptured BTAI might be delayed and allow stabilization, heparinization, and involvement of a higher TEVAR volume surgeon.

Adoption and clinical outcomes of fenestrated endovascular aneurysm repair in a regional, multistate community hospital system

OBJECTIVE

Complex endovascular abdominal aortic aneurysm (AAA) repair techniques have evolved over the last decade, yet patterns of physician and hospital system adoption of fenestrated endovascular aneurysm repair (FEVAR) remain poorly defined. We investigated clinical outcomes, use trends, and surgeon and hospital experience for FEVAR in a large community hospital system.

METHODS

We conducted a retrospective cohort study of all FEVAR procedures within our 5-state hospital system between April 2012 and June 2021. AAA repair volumes (open, EVAR, and FEVAR) were captured at the hospital and surgeon levels using Current Procedural Terminology and International Classification of Diseases codes. Clinical and outcomes data were collected for FEVAR patients. To consider if surgeon or hospital experience influenced outcomes, sequential case number was used to divide patients into surgeon experience and hospital experience groups. Inverse probability weighted and generalized linear mixed models, adjusted for demographics and comorbidities, were built to examine risk-adjusted outcomes for surgeon and hospital experience groups.

RESULTS

Of 3850 patients treated with AAA procedures of any kind between 2012 and 2021, 160 (4.2%) underwent FEVAR. FEVAR procedures were performed by 34 different surgeons at 12 hospitals, with intraoperative complications and unplanned adjunctive procedures occurring in 18.8% (n = 30) and 19.4% (n = 31) of patients, respectively. Among FEVAR patients, in-hospital mortality was 1.3% (n = 2) and postoperative morbidity was 16.9% (n = 27). Renal function decline occurred postoperatively in 5.1% of patients. Early (<30 day) postoperative endoleaks occurred in 15.3% of patients (n = 21). Target vessel patency was 95.6% on initial postoperative imaging. Surgeon and hospital experience had a small positive impact on outcomes after the first one to three cases. Significant decreases in operative time, fluoroscopy time, and estimated blood loss were observed with increased surgeon experience, relative to a surgeon's first case (P < .05). There were lower odds of intraoperative complications after a surgeon's first case (odds ratio [OR], 0.16; 95% confidence interval [CI], 0.03-0.77, for cases 2-3) or after a hospital's first one to three cases (OR, 0.19; 95% CI, 0.04-0.89, for cases 4-8; OR, 0.12; 95% CI, 0.03-0.55 for cases 9-49).

CONCLUSIONS

Clinical outcomes of FEVAR across our hospital system compare favorably with previously published reports. Although system-wide FEVAR adoption increased 3-fold over the last decade, FEVAR continued to be performed by a minority of hospitals in our system. The results from this cohort demonstrate low rates of adverse events, high rates of technical efficiency, and a small impact of surgeon and hospital experience, thereby supporting this advanced endovascular technology as a safe, efficacious, and generalizable treatment alternative to open repair for patients with complex aortic anatomy.

Race-based outcomes of thoracic aortic aneurysms and dissections in the Global Registry for Endovascular Aortic Treatment

OBJECTIVE

This study characterizes racial differences in presentation, as well as short- and long-term outcomes after endovascular treatment of thoracic aortic aneurysm (TAA) and type B aortic dissection (TBAD).

METHODS

We queried the Gore Global Registry for Endovascular Aortic Treatment for thoracic endovascular aortic repairs (TEVARs) performed between 2010 and 2016 and followed through 2022. Pathologies represented were descending TAA, complicated TBAD, and uncomplicated TBAD. Using standard statistical tests, we compared overall and pathology-specific demographics, procedural factors, and outcomes among Black and White patients undergoing TEVAR.

RESULTS

We identified 438 TEVAR cases, including 236 descending TAA, 121 complicated TBAD, and 74 uncomplicated TBAD. Overall, Black patients were younger and had a higher incidence of renal insufficiency (P = .001), whereas White patients had more chronic obstructive pulmonary disease (P = .003) and cardiac arrhythmias (P = .037). In patients treated for descending TAA, Black patients had increased device- and procedure-related complications (34.3% vs 17.4%; P = .014), conversion to open repair (2.9% vs 0%; P = .011) and type II endoleak (5.7% vs 1.0%; P = .040), but no differences in mortality, length of hospital stay, or major adverse cardiovascular events. Whereas outcomes of TEVAR for uncomplicated TBAD were comparable, Black patients more frequently presented with complicated TBAD than White patients (Black, 40.5% vs White, 24.8%; P = .008) and had subsequently greater reintervention rates (28.1% vs 12.4%; P = .012), all-cause mortality (hazard ratio, 4.28; 95% confidence interval, 1.74-10.5; P = .002) and aortic-related mortality (hazard ratio, 16.7; 95% confidence interval, 1.49-186; P = .022).

CONCLUSIONS

Despite increased device- and procedure-related complications, similar short- and long-term outcomes are achieved in Black and White patients undergoing TEVAR for descending TAA and uncomplicated TBAD. However, Black patients are more likely to present with, require reintervention for, and suffer mortality from complicated TBAD.

Higher Surgeon Volume is Associated with Lower Odds of Complication Following TEVAR for Aortic Dissections

OBJECTIVE

This study aimed to understand the impact of surgeon volume on outcomes of thoracic endovascular aortic repair (TEVAR) in patients being treated for aortic dissection.

METHODS

Patients undergoing TEVAR from January 2014 - March 2021 in the Vascular Quality Initiative (VQI) database were analyzed. Patients with aortic dissection who underwent TEVAR were divided into quartiles based on the annual TEVAR volume of their vascular surgeon. The highest quartile, middle two quartiles, and lowest quartile were deemed high volume (HV), moderate volume (MV), and low volume (LV), respectively. Multivariable logistic regressions were performed to compare cohort outcomes in terms any postoperative complication, stroke, spinal cord ischemia, reintervention, and 30-day mortality. A Cox proportional hazard model was used to assess the hazard of overall postoperative mortality.

RESULTS

Amongst 1,217 patients undergoing TEVAR, 321, 621, and 275 were performed by HV, MV, and LV surgeons, respectively. HV performed >19 annual TEVARs, MV surgeons between 5 and 18, and LV surgeons ≤4. Adjusted odds of any postoperative complication revealed that HV and MV surgeons had lower odds of overall postoperative complications [(OR 0.58, (95% CI 0.30 - 0.85), p = 0.011) and (OR 0.60, (95% CI 0.38 - 0.87), p = 0.008)], respectively when compared to LV patients. HV had lower odds of respiratory complications than LV surgeons complications [(OR 0.42, (95% CI 0.17 - 0.93), p = 0.039)]. Adjusted analysis of outcomes including spinal cord ischemia, stroke, myocardial infarction, 30-day mortality, and overall mortality did not reveal statistically significant differences between cohorts.

CONCLUSION

Surgeon volume does not to impact 30-day mortality or long-term mortality after TEVAR for aortic dissection, but the odds of overall postoperative complications were lower for HV and MV surgeons when compared to LV surgeons.

Complications after thoracic endovascular aortic repair for ruptured thoracic aortic aneurysms remain high compared with elective repair

OBJECTIVE

Thoracic endovascular aortic repair (TEVAR) for ruptured thoracic aortic aneurysms is associated with increased perioperative mortality and morbidity compared with intact repair. The purpose of our study was to evaluate the factors associated with the presentation of ruptured aneurysms and adverse outcomes after repair.

METHODS

The Vascular Quality Initiative (VQI) registry was queried (2010-2020) to identify patients who had undergone TEVAR for ruptured and intact thoracic aortic aneurysms. The primary outcome was to identify the factors associated with ruptured thoracic aortic aneurysms. The secondary outcomes included perioperative mortality and morbidity, 5-year survival, and the identification of factors associated with adverse outcomes after TEVAR.

RESULTS

Of the 3039 patients identified with a thoracic aortic aneurysm, 2806 (92%) had undergone repair for an intact aneurysm and 233 (8%) had undergone repair for a ruptured aneurysm. Chronic kidney disease was associated with a greater odds of a presentation with a ruptured aneurysm (odds ratio [OR], 3.1; 95% confidence interval [CI], 2.0-4.9; P < .001). The factors associated with a lower odds of rupture included prior aortic aneurysm repair (OR, 0.71; 95% CI, 0.49-0.97; P = .05), prior smoker (OR, 0.36; 95% CI, 0.24-0.53; P < .001), preoperative beta-blocker therapy (OR, 0.57; 95% CI, 0.41-0.80; P = .001), and preoperative statin therapy (OR, 0.68; 95% CI, 0.49-0.94; P = .020). TEVAR for ruptured thoracic aortic aneurysms was associated with higher perioperative mortality (rupture vs intact, 27% vs 4.6%; OR, 6.6; 95% CI 4.3-10; P < .001) and the composite outcome of mortality, new dialysis, paralysis, and stroke (38% vs 9.5%; OR, 5.1; 95% CI, 3.5-7.4; P < .001). The 5-year survival was significantly lower after TEVAR for ruptured thoracic aortic aneurysms (50% vs 76%; P < .001; hazard ratio, 0.39; 95% CI, 0.29-0.52; P < .001). Preoperative statin therapy was associated with higher 5-year survival (hazard ratio, 1.3; 95% CI, 1.0-1.6; P = .021).

CONCLUSIONS

TEVAR for ruptured thoracic aortic aneurysms results in increased perioperative mortality and morbidity and lower 5-year survival compared with TEVAR for intact aneurysms. Patients with prior aortic aneurysm repair, prior smoking, and preoperative beta-blocker or statin therapy were less likely to present with ruptured thoracic aneurysms. This correlation might be attributed to increased exposure to cardiovascular healthcare providers and, thus, subsequently increased screening and surveillance, allowing for elective repair of thoracic aortic aneurysms.

Low Volume Hospitals Are Not Associated with Inferior Outcomes After Thoracic Endovascular Aortic Repair

BACKGROUND

Thoracic endovascular aortic repair (TEVAR) has been used increasingly to treat complex thoracic aortic pathology. This study aimed to assess hospital volume's impact on outcomes in patients undergoing TEVAR.

STUDY DESIGN

Patients undergoing TEVAR between January 2015 and December 2019 were identified in the Vascular Quality Initiative (VQI) database. The participating centers were grouped into either low-volume hospitals (LVH) or high-volume hospitals (HVH). We assessed the impact of hospital volume on 30-day mortality and major postoperative complications using a multivariable logistic regression analysis.

RESULTS

A total of 3,584 TEVAR patients (asymptomatic = 1,720; symptomatic/ruptured =1,864) were identified at 147 centers. The median average annual number of TEVAR cases at LVH and HVH was 6 and 17 cases, respectively. There was no significant difference in 30-day mortality between LVH and HVH (asymptomatic: 3.7% vs. 3.7%, p = 0.98; symptomatic/rupture: 9.3% vs. 7.3%, p = 0.13). After adjusting for multiple clinical and anatomical factors, being treated in LVH was not associated with increased 30-day mortality (asymptomatic: OR = 0.98, 95% CI: 0.52, 1.87, p = 0.96; symptomatic/rupture: OR = 1.15, 95%CI: 0.75, 1.77, p = 0.53) nor an increased risk of major complications, including renal, neurological, cardiac, pulmonary, and femoral artery access complication (all p > 0.05).

CONCLUSION

Using a large national database, we demonstrate that LVH is not associated with inferior TEVAR outcomes than HVH. The technical aspect of the procedure might play a role in the similarity of outcomes across the different institutional experiences.

Predictors of 30-day readmission and resource utilization after thoracic endovascular aortic repair

OBJECTIVES

The introduction and expansion of thoracic endovascular aortic repair (TEVAR) have revolutionized the treatment of a variety of thoracic aortic diseases. We sought to evaluate the incidence, causes, predictors and costs associated with 30-day readmission after TEVAR in a nationally representative cohort.

METHODS

Adult patients undergoing isolated TEVAR were identified in the National Readmissions Database from 2010 to 2014. Hospital costs were estimated by converting individual hospital charge data adjusted to 2014 consumer price indices. Multivariable logistic regression was utilized to determine hospital- and patient-level factors associated with readmissions.

RESULTS

A total of 24 983 TEVARs were noted during the study period; the average age of the patients was 65 ± 16 years; 40% were women. The most common indication was an intact thoracic aneurysm (43.5%), followed by aortic dissection (30.5%). The average cost of the index admission was $63 644 ± $52 312; the average hospital stay was 11 ± 14 days; the index mortality rate was 6.7%. Readmissions within 30 days occurred in 17.4% of patients. Indications for readmission were varied; the most common aetiologies were cardiac (17.8%), infectious (16.0%) and pulmonary (12.1%). On multivariable analysis, the strongest predictor of readmission was the diagnosis, with a ruptured thoraco-abdominal aneurysm having the highest readmission burden (adjusted odds ratio 2.23, 1.17-4.24; P = 0.015). Notably, hospital volume did not predict index hospital length of stay, costs or 30-day readmissions (all P > 0.10).

CONCLUSIONS

Annual TEVAR volume was not associated with any of the outcomes assessed. Rather, indication for TEVAR was the strongest predictor for many outcomes. As TEVAR becomes increasingly utilized, a focus on cardiac and vascular diseases may reduce readmissions and improve quality of care.

Epidemiology of aortic dissection

Aortic dissection remains a highly morbid diagnosis. The treatment of aortic dissection has undergone several paradigm shifts since it was first understood. However, despite the robust research in treatment, the epidemiology of aortic dissection is limited. In this review, we discuss the historical perspectives of aortic dissection with a review of risk factors and presentation. We review the trends in incidence during the past 40 years, with consideration for sex, race, and ethnicity in admission. We further focus our discussion of the classically described Type B aortic dissection treatment. Lastly, we review the impact of long-term events, readmissions, cost assessments, and quality of life studies of patients with aortic dissection. Care for those with aortic dissection remains a long-term challenge for providers and a multispecialty approach is needed for complete patient management.

A systematic review of the effect of surgeon and hospital volume on survival in aortic, thoracic and fenestrated endovascular aneurysm repair

BACKGROUND

Endovascular aneurysm repair (EVAR) is becoming a mainstay in vascular surgery, both in metropolitan and regional hospitals. This review aims to assess the impact of hospital and surgeon volume on perioperative mortality specific to this surgery type to support the use of this treatment modality extensively.

METHODS

A literature search was performed on multiple dedicated medical databases using a detailed search strategy with terms focusing on hospital volume and EVARs. Inclusion and exclusion criteria were used to screen and evaluate suitable sources, focusing on operators and hospitals performing EVARs and the morbidity/mortality as outcomes. The results were then appraised using a PRISMA framework.

RESULTS

We reviewed 45 articles. Twelve articles met inclusion criteria for complete review. There was no level 1 evidence, and only a single systematic review and meta-analysis. EVAR and thoracic EVAR perioperative mortality had no correlation with hospital volume. Limited evidence was presented for fenestrated EVAR, where a mortality risk based on hospital volume remains unanswered. Open procedures for aneurysm repair had perioperative mortality outcomes that grossly correlated with hospital volume, supporting their use in high-volume centers.

CONCLUSIONS

With open aneurysm repairs having an increased mortality risk in low-volume centers, and endovascular treatment options gaining momentum, there is considerable support for the use of EVAR and thoracic EVAR in smaller regional centers safely and effectively. There is very limited evidence in the use of fenestrated EVAR, which remains unanswered, but presents a significant opportunity for research.

Emergent thoracic endovascular aortic aneurysm repair for ruptured aneurysm: in-hospital and long-term results

The use of thoracic endovascular aortic repair (TEVAR) has rapidly increased following Food and Drug Administration (FDA) approval in 2005. Initially used for the repair of intact thoracic aneurysms and aortic dissections, TEVAR is now routinely used for the treatment of ruptured thoracic aortic aneurysm as well. Emergent TEVAR for the repair of ruptured aneurysm has demonstrated improved perioperative mortality and morbidity compared to traditional open repair. Spinal cord ischemia and permanent paraplegia rates are also lower following TEVAR compared to open repair. However, TEVAR requires routine surveillance and has demonstrated the need for reintervention compared to open repair. Furthermore, the perioperative survival benefits of TEVAR were attenuated on mid-term and long-term survival analysis.

Distribution of Elective Ileal Pouch-Anal Anastomosis Cases for Ulcerative Colitis: a Study Utilizing the University Health System Consortium Database

BACKGROUND

Trends and distribution of ileal pouch-anal anastomosis (IPAA) procedures for patients with ulcerative colitis (UC) are unknown. We examined the frequency, distribution, and volume-outcome relationship for this relatively infrequent procedure using a large national data source.

METHODS

Data were obtained from the University HealthSystem Consortium (UHC) for patients with a primary diagnosis of UC admitted electively and who underwent surgical intervention between 2012 and 2015.

RESULTS

The mean age of the study population (n = 6875) was 43 years and 57% were men. Among these, one-third (n = 2307) underwent an IPAA, while 24% (n = 1160) underwent total abdominal colectomy, 16% (n = 1134) underwent proctectomy, and 2% (n = 108) underwent total proctocolectomy with end ileostomy. The frequency of IPAA cases among all elective surgical cases was relatively stable at 33-35% over the study period. A total of 131 hospitals, out of 279 hospitals participating in the UHC (47%), performed IPAA. UHC contains all inpatient data on more than 140 (> 90%) academic medical centers in the US and their affiliates. Most hospitals (101) performed < 5 cases annually. The median number of IPAA cases performed annually was 1.8 [IQR 0.8 - 4.3]. The top 10 hospitals performed one-half (48%) of IPAA cases, but only 18% of another type of complex pelvic dissection cases such as low anterior resection. Short-term postoperative complications after IPAA, however, were similar regardless of IPAA volume.

CONCLUSIONS

Nearly one-half of IPAA cases were performed at only 10 hospitals out of the 131 hospitals performing IPAA in the study. IPAA procedures are infrequently performed by most academic medical centers in the US. The redistribution of IPAA procedures, likely a result of previously established referral patterns and centralization, has a potential impact on the training of future colorectal fellows as well as access to care.

Mid-Term Survival after Thoracic Endovascular Aortic Repair by Indication in the Medicare Population

BACKGROUND

Thoracic endovascular aortic repair (TEVAR) is indicated for treatment of aneurysms, dissections, and traumatic injury. We describe mid-term mortality and reintervention rates in Medicare beneficiaries undergoing TEVAR.

STUDY DESIGN

Patients who underwent TEVAR between 2006 and 2014 were identified by CPT codes in a 20% Medicare sample. Indication for aortic repair (aneurysm, dissection, trauma) was ascertained via ICD-9 codes. Follow-up was evaluated until 2015. Kaplan-Meier survival analysis and Cox regression were used to compare mortality, with reintervention and mortality rates expressed as a composite outcome in a hazard ratio with 95% confidence interval (hazard ratio [HR] 95% CI).

RESULTS

There were 3,095 patients who underwent TEVAR during the study period: 1,465 (47%) for aneurysm, 1,448 (47%) for dissection, and 182 (5.9%) for trauma. Mean patient age was 74.4 years, and 44.5% were female. Median follow-up was 2.7 years. The overall 30-day, 1-year, and 5-year, and 8-year survival rates were 93%, 78%, 49%, and 33%, respectively. Thirty-day mortality was highest in traumatic indications, but overall mortality was highest in patients undergoing TEVAR for aneurysm. Freedom from combined reintervention and mortality at 30 days, 1 year, 5 years, and 8 years was 89%, 73%, 43%, and 29%, respectively. Reintervention was highest in patients undergoing TEVAR for dissection (12.8%), followed by aneurysm (10.0%) and trauma (5.5%). Advanced age (HR 1.03 per year, 95% CI 1.02-1.03), congestive heart failure (CHF) (HR 1.48, 95% CI 1.33-1.65), dementia (HR 1.40, 95% CI 1.14-1.28), and rupture (HR 1.38, 95% CI 1.24-1.54) were associated with mortality.

CONCLUSIONS

Midterm survival is lower in patients who undergo TEVAR for dissection and aneurysm compared with trauma. Aneurysmal disease, advanced age, CHF, dementia, and aortic rupture are associated with mortality and reintervention in TEVAR.

Volume-Outcome Relationships in Surgical and Endovascular Repair of Aortic Dissection

BACKGROUND

As surgical mortality decreases and endovascular utilization increases, it is unknown whether volume-outcome relationships exist in thoracic aortic dissection repair. We characterized volume-outcome relationships for surgical and endovascular management of thoracic aortic dissection.

METHODS

Patients aged more than 18 years undergoing repair of thoracic aortic dissection in the United States between 2010 and 2014 were identified in seven all-payer state inpatient administrative databases. Patients were divided into groups based on type of repair: surgical repair of type A dissection (TAAD), surgical repair of type B dissection (TBAD), and endovascular repair (TEVAR). Hierarchical logistic regression models evaluated the association between hospital volume and in-hospital mortality.

RESULTS

Overall in-hospital mortality rate was 13.4% (890 of 6650), highest after TAAD (463 of 2918, 15.9%), followed by TBAD (270 of 1934, 14.0%) and TEVAR (157 of 1798, 8.7%). Volume-outcome relationships for adjusted in-hospital mortality were demonstrated for TAAD and TBAD (P-trend < .001), but not TEVAR (P-trend = .11). Adjusted in-hospital mortality differed most for TAAD (fewer than 3 cases per year: 21%, 95% confidence interval, 18% to 24%; vs 11 or more cases per year: 12%, 95% confidence interval, 8% to 16%; P < .001) and TBAD (fewer than 2 cases per year: 18%, 95% confidence interval, 15% to 22%; vs 11 or more cases per year: 9%, 95% confidence interval, 5% to 12%; P < .001), whereas TEVAR did not differ between quartiles. Adjusted mortality was lower at centers with 26 or more overall annual thoracic dissection repairs, compared with any of the three lower-volume quartiles (P < .001).

CONCLUSIONS

This study demonstrated lower mortality at high-volume hospitals for overall repair of aortic dissection, persisting separately for surgical repair of TAAD and TBAD, but not TEVAR. As endovascular technology advances and practice patterns consequently change, analyses should focus on understanding the balance between procedural volume, mortality, and access to care for thoracic aortic dissection.

CNB-001 reduces paraplegia in rabbits following spinal cord ischemia

Spinal cord ischemia associated with trauma and surgical procedures including thoraco-abdominal aortic aneurysm repair and thoracic endovascular aortic repair results in devastating clinical deficits in patients. Because spinal cord ischemia is inadequately treated, we studied the effects of [4-((1E)-2-(5-(4-hydroxy-3-methoxystyryl-)-1-phenyl-1H-pyrazoyl-3-yl) vinyl)-2-methoxy-phenol)] (CNB-001), a novel curcumin-based compound, in a rabbit SCI model. CNB-001 is known to inhibit human 5-lipoxygenase and 15-lipoxygenase and reduce the ischemia-induced inflammatory response. Moreover, CNB-001 can reduce the level of oxidative stress markers and potentiate brain-derived neurotrophic factor and brain-derived neurotrophic factor receptor signaling. The Tarlov scale and quantal analysis technique results revealed that CNB-001 administered as an intravenous dose (bolus) 30 minutes prior to spinal cord ischemia improved the behaviors of female New Zealand White rabbits. The improvements were similar to those produced by the uncompetitive N-methyl-D-aspartate receptor antagonist memantine. At 48 hours after aortic occlusion, there was a 42.7% increase (P < 0.05) in tolerated ischemia duration (n = 14) for rabbits treated with CNB-001 (n = 16), and a 72.3% increase for rabbits treated with the positive control memantine (P < 0.05) (n = 23) compared to vehicle-treated ischemic rabbits (n = 22). CNB-001 is a potential important novel treatment for spinal cord ischemia induced by aortic occlusion. All experiments were approved by the CSMC Institutional Animal Care and Use Committee (IACUC #4311) on November 1, 2012.