Development of a Novel Society of Thoracic Surgeons Aortic Surgery Mortality and Morbidity Risk Model.

BACKGROUND: The Society of Thoracic Surgeons Adult Cardiac Surgery Database (STS-ACSD) was expanded in 2017 to include more granular detail on thoracic aortic surgeries. We describe the first validated risk model in thoracic aortic surgery from the STS-ACSD. METHODS: The study population consisted of patients undergoing non-emergent isolated ascending aortic aneurysm repair using open or clamped distal anastomoses, including those requiring aortic root or valve replacement. Model outcomes included operative mortality, 30-day major morbidity (cardiac reoperation, deep sternal wound infection, stroke, prolonged ventilation, renal failure) and a composite of both. To select the predictors, univariate associations and clinical face validity of models were examined. Models were evaluated by their ability to distinguish between patients with and without specific outcomes (discrimination) and their predictive accuracy (calibration). RESULTS: Between 2017 and 2021, 24,051 eligible patients underwent ascending aortic aneurysm surgery at 905 hospitals. Procedures included 8,913 aortic root replacements, 2,135 valve-sparing root replacements, 7,545 ascending aortic replacements with AVR, and 5,458 ascending aortic replacements. Circulatory arrest was performed in 7,316 (30.4%) of cases. Operative mortality was 1.9%, and 12.2% of patients experienced major morbidity including 2.4% incidence of stroke. The adjusted C-statistics for the model were 0.74, 0.67 and 0.67 for mortality, morbidity and the composite, respectively. Previous stroke and circulatory arrest were associated with new stroke. Genetic aortopathy was associated with less mortality. CONCLUSIONS: A new STS-ACSD risk model to predict mortality and morbidity after ascending aneurysm surgery has been developed, and predictors of better and worse outcomes have been identified.

Polygenic Scoring for Detection of Ascending Thoracic Aortic Dilation.

BACKGROUND: Ascending thoracic aortic dilation is a complex heritable trait that involves modifiable and nonmodifiable risk factors. Polygenic scores (PGS) are increasingly used to assess risk for complex diseases. The degree to which a PGS can improve aortic diameter prediction in diverse populations is unknown. Presently, we tested whether adding a PGS to clinical prediction algorithms improves performance in a diverse biobank. METHODS: The analytic cohort comprised 6235 Penn Medicine Biobank participants with available echocardiography and clinical data linked to genome-wide genotype data. Linear regression models were used to integrate PGS weights derived from a genome-wide association study of thoracic aortic diameter performed in the UK Biobank and were compared with the performance of the previously published aorta optimized regression for thoracic aneurysm (AORTA) score. RESULTS: Cohort participants had a median age of 61 years (IQR, 53-70) and a mean ascending aortic diameter of 3.36 cm (SD, 0.49). Fifty-five percent were male, and 33% were genetically similar to an African reference population. Compared with the AORTA score, which explained 30.6% (95% CI, 29.9%-31.4%) of the variance in aortic diameter, AORTA score+UK Biobank-derived PGS explained 33.1%, (95% CI, 32.3%-33.8%), the reweighted AORTA score explained 32.5% (95% CI, 31.8%-33.2%), and the reweighted AORTA score+UK Biobank-derived PGS explained 34.9% (95% CI, 34.2%-35.6%). When stratified by population, models including the UK Biobank-derived PGS consistently improved upon the clinical AORTA score among individuals genetically similar to a European reference population but conferred minimal improvement among individuals genetically similar to an African reference population. Comparable performance disparities were observed in models developed to discriminate cases/noncases of thoracic aortic dilation (≥4.0 cm). CONCLUSIONS: We demonstrated that inclusion of a UK Biobank-derived PGS to the AORTA score confers a clinically meaningful improvement in model performance only among individuals genetically similar to European reference populations and may exacerbate existing health care disparities.

Outcomes of a Novel Single Branched Aortic Stent Graft for Treatment of Type B Aortic Dissection.

BACKGROUND: Intervention on Type B dissection frequently requires landing the proximal edge of the stent graft between the left common carotid artery and left subclavian artery (LSA). The Gore® TAG® Thoracic Branch Endoprosthesis (TBE) is a technology which allows LSA preservation with a single internal branch. METHODS: This study was a prospective non-randomized single-arm clinical trial of patients with type B aortic dissection that were treated with the single branched device. Patients with operative indications for acute, chronic or residual Type B dissections that originated distal to the origin of a left subclavian artery suitable for branch graft placement were eligible for the study. Native aortic and surgical graft proximal landing zones were eligible. RESULTS: Among the 132 patients, there were 25 (18.9%) acute type B dissections, 79 (59.8%) of chronic type B dissections and 28 (21.1%) of residual dissections after previous open Type A repair. Percutaneous access was used in 105 (79.5%) patients. Overall, 30-day mortality occurred in 6 patients (4.5%). The overall 30 day stroke rate was 2/132(1.5%) and the one-year freedom from stroke was 96.8%. Device Technical Success and Procedural Success was achieved in 129/132(97.7%) and 110/132(83.3%) of subjects, respectively and there was one instance of loss of side branch patency. There was no persistent antegrade false lumen flow observed. CONCLUSIONS: In this study of a novel branched endograft device to preserve the LSA in patients with type B dissection undergoing TEVAR, we demonstrate acceptable safety and efficacy outcomes at one year.

Long-Term Outcomes of Antegrade Thoracic Stent Grafting During Repair of Acute DeBakey I Dissection.

BACKGROUND: We aim to evaluate the impact of antegrade stenting of the distal arch and proximal descending aorta combined with non-total arch procedures in acute type A aortic dissection. METHODS: From 2005 to 2022, 733 nonsyndromic patients presented with acute DeBakey type I aortic dissection and underwent non-total arch procedure. Ninety-five patients underwent antegrade stenting and 638 did not. Propensity-score analysis was performed, and 95 optimal pairs were created. Survival was estimated using the Kaplan-Meier method and cumulative incidence of reintervention with death as a competing event was calculated and compared using Gray's method. RESULTS: Survival estimates at 10 years after propensity score matching were similar between both groups, 58.9% (95% CI, 46.5%-74.5%) vs 58.4% (95% CI, 48.3%-70.6%) (P = .6) in the non-stented vs stented group. Cumulative incidence of reintervention with competing risk of death at 10 years after propensity matching was 27% (95% CI, 17%-37%) vs 22% (95% CI, 14%-32%) (P = .44), respectively. CONCLUSIONS: Antegrade thoracic endovascular aortic repair may be beneficial for remodeling and facilitating future endovascular reinterventions and reduces the occurrence of reintervention for malperfusion.

Performance of the open-first repair strategy in type A aortic dissection with mesenteric malperfusion syndrome eligible for delayed repair.

OBJECTIVE: For patients with type A aortic dissection complicated by mesenteric malperfusion syndrome, some centers advocate a nontraditional approach based on up-front endovascular intervention and delayed open repair. However, the efficacy of this strategy cannot be understood without first understanding outcomes of the traditional open-first strategy in the same select patient population eligible for delayed repair, applying modern techniques of hybrid aortic surgery. METHODS: Patients with acute type A aortic dissection and mesenteric malperfusion syndrome were queried from a single institution. Those presenting with aortic rupture, tamponade, or cardiogenic shock (ineligible for delayed repair) were excluded. Patients were managed with immediate open aortic repair. Short-term and long-term outcomes are reported. RESULTS: A total of 1228 patients were treated for acute type A dissection in the study period, of whom 77 were included in the mesenteric malperfusion syndrome cohort. In-hospital mortality was 29% compared with 39% in an identically selected mesenteric malperfusion syndrome population undergoing delayed repair reported previously. Among patients with mesenteric malperfusion syndrome, 32% underwent additional procedures addressing distal malperfusion in a hybrid operating room during or after open repair. Concomitant proximal malperfusion (coronary, cerebral, or upper extremity) was common in the mesenteric malperfusion syndrome cohort, present in 35% of cases. Although early mortality was greater in the mesenteric malperfusion syndrome cohort compared with all acute type A dissections, 10-year survival among those discharged alive was similar (65% vs 59%, P = .18). CONCLUSIONS: The traditional open-first repair strategy performs equal to or better than the delayed repair strategy for patients with mesenteric malperfusion syndrome eligible for delayed repair.

Initial Outcomes of the Gore TAG Thoracic Branch Endoprosthesis for Endovascular Repair of Blunt Thoracic Aortic Injury.

BACKGROUND: Endovascular repair of blunt thoracic aortic injury (BTAI) has dramatically reduced the morbidity and mortality of intervention. Injuries requiring zone 2 coverage of the aorta traditionally require left subclavian artery (LSA) sacrifice or open revascularization. Furthermore, these injuries are associated with an increased risk of in-hospital mortality and long-term morbidity. Here we report 1-year outcomes of total endovascular repair of BTAI with the GORE® TAG® Thoracic Branch Endoprosthesis for LSA preservation. METHODS: Across 34 investigative sites, 9 patients with BTAI requiring LSA coverage were enrolled in a nonrandomized, prospective study of a single-branched aortic endograft. The thoracic branch endoprosthesis device allows for graft placement proximal to the LSA and incorporates a single side branch for LSA perfusion. RESULTS: This initial cohort included 8 male and 1 female patient with a median age of 43 (22, 76) and 12 months of follow-up. Five total years of follow-up are planned. All participants had grade 3 BTAI. All procedures took place between 2018 and 2019. The median injury severity score was 2 (0, 66). The median procedure time was 109 min (78, 162). All aortic injuries were repaired under general anesthesia and with heparinization. A spinal drain was used in one patient. Post-deployment balloon angioplasty was conducted in one case at the distal landing zone. There was one asymptomatic LSA branch occlusion 6 months after repair. It was attributed to the purposeful proximal deployment of the branch stent to accommodate an early vertebral takeoff. The occlusion did not require revascularization. There were no strokes, mortalities, or aortic adverse events (migration, endoleak, native aortic expansion, dissection, or thrombosis) through 12 months of follow-up. CONCLUSIONS: Initial cohort outcomes suggest that endovascular repair of zone 2 BTAI is feasible and has favorable outcomes using the thoracic branch device with LSA preservation. Additional cases and longer-term follow-up are required for a definitive assessment of the device's safety and durability in traumatic aortic injuries.

Axillary vs Femoral Arterial Cannulation in Acute Type A Dissection: International Multicenter Data.

BACKGROUND: Cannulation strategy in acute type A dissection (ATAD) varies widely without known gold standards. This study compared ATAD outcomes of axillary vs femoral artery cannulation in a large cohort from the International Registry of Acute Aortic Dissection (IRAD). METHODS: The study retrospectively reviewed 2145 patients from the IRAD Interventional Cohort (1996-2021) who underwent ATAD repair with axillary or femoral cannulation (axillary group: n = 1106 [52%]; femoral group: n = 1039 [48%]). End points included the following: early mortality; neurologic, respiratory, and renal complications; malperfusion; and tamponade. All outcomes are presented as axillary with respect to femoral. RESULTS: The proportion of patients younger than 70 years in both groups was similar (n = 1577 [74%]), as were bicuspid aortic valve, Marfan syndrome, and previous dissection. Patients with femoral cannulation had slightly more aortic insufficiency (408 [55%] vs 429 [60%]; P = .058) and coronary involvement (48 [8%] vs 70 [13%]; P = .022]. Patients with axillary cannulation underwent more total aortic arch (156 [15%] vs 106 [11%]; P = .02) and valve-sparing root replacements (220 [22%] vs 112 [12%]; P < .001). More patients with femoral cannulation underwent commissural resuspension (269 [30.9%] vs 324 [35.3%]; P = .05). Valve replacement rates were not different. The mean duration of cardiopulmonary bypass was longer in the femoral group (190 [149-237] minutes vs 196 [159-247] minutes; P = .037). In-hospital mortality was similar between the axillary (n = 165 [15%]) and femoral (n = 149 [14%]) groups (P = .7). Furthermore, there were no differences in stroke, visceral ischemia, tamponade, respiratory insufficiency, coma, or spinal cord ischemia. CONCLUSIONS: Axillary cannulation is associated with a more stable ATAD presentation, but it is a more extensive intervention compared with femoral cannulation. Both procedures have equivalent early mortality, stroke, tamponade, and malperfusion outcomes after statistical adjustment.

Valve-Sparing Aortic Root Replacement State-of-the-Art Review, Part II: Surgical Techniques.

Aortic valve disease is common, and valve-preserving operations are preferred whenever possible. Valve-sparing aortic root replacement (VSRR) has become an important tool for managing aortic root pathology in children and adults. The learning curve for this operation is challenging, but with increasing experience and technical modifications, early and late outcomes continue to improve. Durable long term results vary based on underlying anatomy, pathology, and patient selection, as well as surgeon expertise. Part II of this VSRR State-of-the-Art Review article provides technical pearls related to VSRR.

Valve-Sparing Aortic Root Replacement State-of-the-Art Review, Part I: Anatomy and Physiology.

Aortic valve disease is common, and valve-preserving operations are preferred whenever possible. Valve-sparing aortic root replacement has become an important tool for managing aortic root pathology in children and adults. The learning curve for this operation is challenging, but with increasing experience and technical modifications, early and late outcomes continue to improve. Durable long-term results vary based on the underlying anatomy, pathology, and patient selection, as well as surgeon expertise. The first installment of this Valve-Sparing Aortic Root Replacement State-of-the-Art Review article addresses patient anatomy and physiology as it relates to candidacy for VSRR.

The non to moderately dilated root in acute type A aortic dissection: outcomes of the PENN-BERN registry in young, non-syndromic patients.

OBJECTIVES: There is an ongoing debate regarding whether patients benefit more from root replacement compared to a reconstruction of the sinuses of Valsalva in acute type A aortic dissection (aTAAD). In those with known or suspected connective tissue disorders, root replacement is considered appropriate. However, there are currently no diameter-based guidelines regarding the best approach in patients with minimally to moderately dilated root and no connective tissue disorders. METHODS: From January 2005 to December 2022, a two-centre registry of aTAAD was created. Patients were included based on their age (≤60 years), the absence of root entry and dilatation >50 mm and the absence of syndromic hereditable aortic disease. Patients were divided into 2 groups based on the proximal procedure, root reconstruction and root replacement. Propensity score pair matching was performed based on preoperative characteristics. RESULTS: Cumulative incidence of reintervention at 10 years was slightly higher after root reconstruction 13% vs 3.9% in the matched group (P = 0.040). Survival at 10 years was not affected by the procedure independently of the matching 72.1% vs 71.4% (P = 0.2). Uni- and multivariate Cox regressions showed that a root diameter of >40 mm was associated with a hazard ratio of 7.7 (95% confidence interval 2.6-23) and 5.4 (7-17), respectively, for reoperation for aneurysm and pseudoaneurysm. CONCLUSIONS: Rate of reoperation due to proximal pseudoaneurysm and aneurysm could be significantly reduced with a lower threshold of 40 mm to replace the aortic root in aTAAD than in elective cases.

Five-Year Outcomes After Bicuspid Aortic Valve Replacement With a Novel Tissue Bioprosthesis.

BACKGROUND: This study investigated the safety and effectiveness of surgical aortic valve replacement with RESILIA tissue (Edwards Lifesciences) through 5 years in patients with native bicuspid aortic valves. Outcomes were compared with those for patients with tricuspid aortic valves. METHODS: Of 689 patients from the COMMENCE (ProspeCtive, nOn-randoMized, MulticENter) trial who received the study valve, 645 had documented native valve morphology and core laboratory-evaluable echocardiograms from any postoperative visit, which were used to model hemodynamic outcomes over 5 years. Linear mixed-effects models were used to estimate longitudinal changes in mean gradient and effective orifice area. RESULTS: Patients with native bicuspid aortic valves (n = 214) were more than a decade younger than those with tricuspid aortic valves (n = 458; 59.8 ± 12.4 years vs 70.2 ± 9.5 years; P < .001). The bicuspid aortic valve cohort exhibited no structural valve deterioration over 5 years, and rates of paravalvular leak and transvalvular regurgitation were low (0.7% and 2.9%, respectively [all mild] at 5 years). These outcomes mirrored those in patients with native tricuspid aortic valves. The model-estimated postoperative mean gradient and effective orifice area, as well as the rate of change of these outcomes, adjusted for age, body surface area, and bioprosthesis size, did not differ between the 2 cohorts. CONCLUSIONS: Among patients with bicuspid aortic valves, RESILIA tissue valves demonstrated excellent outcomes to 5 years, including no structural valve deterioration and very low rates of paravalvular and transvalvular regurgitation. These results are encouraging for RESILIA tissue durability in young patients.

Validation of the GERAADA score to predict 30-day mortality in acute type A aortic dissection in a single high-volume aortic centre.

OBJECTIVES: This study aimed to evaluate employing the German Registry of Acute Aortic Dissection Type A (GERAADA) score to predict 30-day mortality in an aortic centre in the USA. METHODS: Between January 2010 and June 2021, 689 consecutive patients underwent surgery for acute type A dissection at a single institution. Excluded were patients with missing clinical data (N = 4). The GERAADA risk score was retrospectively calculated via a web-based application. Model discrimination power was calculated with c-statistics from logistic regression and reported as the area under the receiver operating characteristic curve with 95% confidence intervals. The calibration was measured by calculating the observed versus estimated mortality ratio. The Brier score was used for the overall model evaluation. RESULTS: Included were 685 patients [mean age 60.6 years (SD: 13.5), 64.8% male] who underwent surgery for acute type A aortic dissection. The 30-day mortality rate was 12.0%. The GERAADA score demonstrated very good discrimination power with an area under the receiver operating characteristic curve of 0.762 (95% confidence interval 0.703-0.821). The entire cohort's observed versus estimated mortality ratio was 0.543 (0.439-0.648), indicating an overestimation of the model-calculated risk. The Brier score was 0.010, thus revealing the model's acceptable overall performance. CONCLUSIONS: The GERAADA score is a practical and easily accessible tool for reliably estimating the 30-day mortality risk of patients undergoing surgery for acute type A aortic dissection. This model may naturally overestimate risk in patients undergoing surgery in experienced aortic centres.

Seven-year outcomes following aortic valve replacement with a novel tissue bioprosthesis.

OBJECTIVE: As bioprosthetic aortic valve replacement (AVR) extends to younger cohorts, tissue durability is of paramount importance. We report 7-year outcomes from an AVR bioprosthesis utilizing novel tissue. METHODS: This was an international investigational device exemption trial for novel AVR with annual follow-up and a subset re-consented at 5 years for extended 10-year follow-up. Safety end points and echocardiographic measurements were adjudicated by an independent clinical events committee and by a dedicated core laboratory, respectively. RESULTS: Between January 2013 and March 2016, 689 patients underwent AVR with the study valve. Mean age was 66.9 ± 11.6 years, Society of Thoracic Surgeons risk score was 2.0% ± 1.8%, and 74.3% of patients were New York Heart Association functional class II and III. Five-year follow-up was completed by 512 patients, and 225 re-consented for extended follow-up. Follow-up duration was 5.3 ± 2.2 years (3665.6 patient-years), and 194 and 195 patients completed 6- and 7-year follow-ups, respectively. One-, 5-, and 7-year freedom from all-cause mortality was 97.7%, 89.4%, and 85.4%, respectively. Freedom from structural valve deterioration at 7 years was 99.3%. At 7 years, effective orifice area and mean gradients were 1.82 ± 0.57 cm2 (n = 153), and 9.4 ± 4.5 mm Hg (n = 157), respectively. At 7 years, predominantly none (96.8% [152 out of 157]) or trivial/trace (2.5% [4 out of 157]) paravalvular regurgitation and none (84.7% [133 out of 157]) or trivial/trace (11.5% [18 out of 157]) transvalvular regurgitation were observed. CONCLUSIONS: We report the longest surgical AVR follow-up with novel tissue in an investigational device exemption trial utilizing an independent clinical events committee and an echocardiography core laboratory. This tissue demonstrates excellent outcomes through 7 years and is the benchmark for future surgical and transcatheter prostheses.

Using a polygenic score to account for genomic risk factors in a model to detect individuals with dilated ascending thoracic aortas.

Background: Ascending thoracic aortic dilation is a complex trait that involves modifiable and non-modifiable risk factors and can lead to thoracic aortic aneurysm and dissection. Clinical risk factors have been shown to predict ascending thoracic aortic diameter. Polygenic scores (PGS) are increasingly used to assess clinical risk for multifactorial diseases. The degree to which a PGS can improve aortic diameter prediction is not known. In this study we tested the extent to which the addition of a PGS to clinical prediction algorithms improves the prediction of aortic diameter. Methods: The patient cohort comprised 6,790 Penn Medicine Biobank (PMBB) participants with available echocardiography and clinical data linked to genome-wide genotype data. Linear regression models were used to integrate PGS weights derived from a large genome wide association study of thoracic aortic diameter in the UK biobank and were compared to the performance of the standard and a reweighted variation of the recently published AORTA Score. Results: Cohort participants were 56% male, had a median age of 61 years (IQR 52-70) with a mean ascending aortic diameter of 3.4 cm (SD 0.5). Compared to the AORTA Score which explained 28.4% (95% CI 28.1% to 29.2%) of the variance in aortic diameter, AORTA Score + PGS explained 28.8%, (95% CI 28.1% to 29.6%), the reweighted AORTA score explained 30.4% (95% CI 29.6% to 31.2%), and the reweighted AORTA Score + PGS explained 31.0% (95% CI 30.2% to 31.8%). The addition of a PGS to either the AORTA Score or the reweighted AORTA Score improved model sensitivity for the identifying individuals with a thoracic aortic diameter ≥ 4 cm. The respective areas under the receiver operator characteristic curve for the AORTA Score + PGS (0.771, 95% CI 0.756 to 0.787) and reweighted AORTA Score + PGS (0.785, 95% CI 0.770 to 0.800) were greater than the standard AORTA Score (0.767, 95% CI 0.751 to 0.783) and reweighted AORTA Score (0.780 95% CI 0.765 to 0.795). Conclusions: We demonstrated that inclusion of a PGS to the AORTA Score results in a small but clinically meaningful performance enhancement. Further investigation is necessary to determine if combining genetic and clinical risk prediction improves outcomes for thoracic aortic disease.

Outcomes of aortic valve repair with the reimplantation technique and maintenance of commissural orientation.

Background: Debate still persists on whether valve-sparing root reimplantation (VSRR) of a very asymmetric bicuspid aortic valve (BAV) should be completed such that the asymmetry of the native commissural orientation is retained, or if it should be made symmetric (180°-180°). Herein, we present our approach, in which the native asymmetry is preserved, and the valve is reimplanted in a 210°-150° orientation. Methods: A retrospective review was performed of 130 patients with BAV who underwent VSRR between January 1, 2004 and March 1, 2023 at a single institution. Of this total, 37 were reimplanted asymmetrically (210°-150°). The primary outcome was > moderate aortic insufficiency (AI). Secondary outcomes included severe aortic stenosis (AS), reintervention, and survival. Results: The included 37 patients were mostly male [94.6% (35/37)] with mean age of 46.3 years, and with low rates of comorbidities. At least moderate AI was present in 40.5% (15/37) prior to surgery. All BAV in this series were Sievers Type 1 with a mean commissural angle of 128.2°. Leaflet repair was required in 81.1% (30/37), most commonly involving central plication of the conjoined cusp [96.7% (29/30)] and raphe release [73.3% (22/30)]. There was no 30-day mortality or stroke. At 10 years, the cumulative incidences of > moderate AI, severe AS, and reintervention were 7.6% (0-17.2%), 7.1% (0-19.7%), and 5.3% (0.3-22%), respectively. There was no mortality for the entire duration of the study period. Conclusions: This series demonstrates excellent 10-year outcomes of maintaining commissural orientation in asymmetric BAV reimplantation procedures. However, further study with additional patients, longer follow-up, and direct comparison to symmetric reimplantation for similar BAV morphology is required.