Impact of nondiameter aortic indices on surgical eligibility: Results from the Treatment in Thoracic Aortic Aneurysm: Surgery Versus Surveillance (TITAN: SvS) randomized controlled trial.

OBJECTIVES: Traditional criterion for intervention on an asymptomatic ascending aortic aneurysm has been a maximal aortic diameter of 5.5 cm or more. The 2022 American College of Cardiology/American Heart Association aortic guidelines adopted cross-sectional aortic area/height ratio, aortic size index, and aortic height index as alternate parameters for surgical intervention. The objective of this study was to evaluate the impact of using these newer indices on patient eligibility for surgical intervention in a prospective, multicenter cohort with moderate-sized ascending aortic aneurysms between 5.0 and 5.4 cm. METHODS: Patients enrolled from 2018 to 2023 in the randomization or registry arms of the multicenter trial, Treatment In Thoracic Aortic aNeurysm: Surgery versus Surveillance, were included in the study. Clinical data were captured prospectively in an online database. Imaging data were derived from a core computed laboratory. RESULTS: Among the 329 included patients, 20% were female. Mean age was 65.0 ± 11.6 years, and mean maximal aortic diameter was 50.8 ± 3.9 mm. In the one-third of all patients (n = 109) who met any 1 of the 3 criteria (ie, aortic size index ≥3.08 cm/m2, aortic height index ≥3.21 cm/m, or cross-sectional aortic area/height ≥ 10 cm2/m), their mean maximal aortic diameter was 52.5 ± 0.52 mm. Alternate criteria were most commonly met in women compared with men: 20% versus 2% for aortic size index (P < .001), 39% versus 5% for aortic height index (P < .001), and 39% versus 21% for cross-sectional aortic area/height (P = .002), respectively. CONCLUSIONS: One-third of patients in Treatment In Thoracic Aortic aNeurysm: Surgery versus Surveillance would meet criteria for surgical intervention based on novel parameters versus the classic definition of diameter 5.5 cm or more. Surgical thresholds for aortic size index, aortic height index, or cross-sectional aortic area/height ratio are more likely to be met in female patients compared with male patients.

Association of Cerebral Oximetry With Brain Ischemic Lesions and Functional Outcomes in Arch Repair.

BACKGROUND: This exploratory analysis of the randomized controlled Aortic Surgery Cerebral Protection Evaluation CardioLink-3 trial sought to determine if cerebral oximetry desaturation during elective proximal arch repair is associated with detrimental postoperative neuroradiologic and neurofunctional outcomes. METHODS: Cerebral oximetry and pre- and postoperative brain magnetic resonance imaging data from 101 participants were analyzed. Oximetry data from the trial allocation groups were compared; the relationships between cerebral oximetry indices and new ischemic cerebral lesions on magnetic resonance imaging and neurologic outcomes were also evaluated. RESULTS: Total cerebral desaturation events (>20% decrease from baseline) on the left (median [interquartile range], 1 [1-3] vs 1.5 [0.5-3] with innominate and axillary cannulation; P = .80) were comparable to those on the right (1 [1-3] vs 1 [0-3]; P = .75) as were the total area under the curve of desaturation (left, P = .61; right, P = .84). Seventy patients had new ischemic lesions, among whom 36 had new severe lesions. Total desaturation events and area under the curve of desaturation were similar in patients with and without new ischemic lesions or severe lesions. The nadir regional cerebral saturation was lower on the left (49% [41-56]) than the right (53% [44-59]); left desaturation episodes were associated with lower postoperative cognitive test scores (P = .004). CONCLUSIONS: The innominate and axillary cannulation techniques for elective proximal arch repair with unilateral antegrade cerebral perfusion were associated with similar occurrences of cerebral oximetry desaturation and neither were associated with new ischemic lesions.

A prebifurcated axillobifemoral polytetrafluoroethylene graft simplifies carotid to carotid to subclavian bypass.

The use of thoracic endovascular aortic repair for thoracic aortic disease will necessitate cervical debranching in cases involving the proximal arch. We have presented the case of a 57-year-old athletic woman who had developed a type A dissection that extended to the bilateral iliac arteries. After hemiarch repair, she underwent staged cervical debranching with carotid-carotid-subclavian bypass using a prebifurcated axillobifemoral graft and subsequent thoracic endovascular aortic repair. We have detailed her successful clinical course and described the benefits of using a prebifurcated graft for cervical debranching in hybrid repairs of aortic arch pathology.

Risk score for arch reconstruction under circulatory arrest with hypothermia: The ARCH score.

OBJECTIVE: Currently, there is no risk scores built to predict risk in thoracic aortic surgery. This study aims to develop and internally validate a risk prediction score for patients who require arch reconstruction with hypothermic circulatory arrest. METHODS: From 2002 to 2018, data for 2270 patients who underwent aortic arch surgery in 12 institutions in Canada were retrospectively collected. The outcomes modeled included in-hospital mortality and a modified Society of Thoracic Surgeons-defined composite for mortality or major morbidity. Multivariable logistic regression using least absolute shrinkage and selection operator selection method and mixed-effect regression model was used to select the predictors. Internal calibration of the final models is presented with an observed-versus-predicted plot. RESULTS: There were 182 in-hospital deaths (8.0%), and the incidence of Society of Thoracic Surgeons-defined composite for mortality or major morbidity was 27.9%. Variables that increased risk of mortality are age, chronic obstructive pulmonary disease, atrial fibrillation, peripheral vascular disease, New York Heart Association class ≥III symptoms, acute aortic dissection or rupture, use of elephant trunk, concomitant surgery, and increased cardiopulmonary bypass time, with median c-statistics of 0.85 on internal validation. The c-statistics was 0.77 for the model predicting Society of Thoracic Surgeons-defined composite. Internal assessment shows good overall calibration for both models. CONCLUSIONS: We developed and internally validated a risk score for patients undergoing arch surgery requiring hypothermic circulatory arrest using a multicenter database. Once externally validated, the ARCH (Arch Reconstruction under Circulatory arrest with Hypothermia) score would allow for better patient risk-stratification and aid in the decision-making process for surgeons and patient prior to surgery.

A randomized trial comparing axillary versus innominate artery cannulation for aortic arch surgery.

BACKGROUND: Cerebral protection remains the cornerstone of successful aortic surgery; however, there is no consensus as to the optimal strategy. OBJECTIVE: To compare the safety and efficacy of innominate to axillary artery cannulation for delivering antegrade cerebral protection during proximal aortic arch surgery. METHODS: This randomized controlled trial (The Aortic Surgery Cerebral Protection Evaluation CardioLink-3 Trial, ClinicalTrials.gov Identifier: NCT02554032), conducted across 6 Canadian centers between January 2015 and June 2018, allocated 111 individuals to innominate or axillary artery cannulation. The primary safety outcome was neuroprotection per the appearance of new severe ischemic lesions on the postoperative diffusion-weighted-magnetic resonance imaging. The primary efficacy outcome was the difference in total operative time. Secondary outcomes included 30-day all-cause mortality and postoperative stroke. RESULTS: One hundred two individuals (mean age, 63 ± 11 years) were in the primary safety per-protocol analysis. Baseline characteristics between the groups were similar. New severe ischemic lesions occurred in 19 participants (38.8%) in the axillary versus 18 (34%) in the innominate group (P for noninferiority = .0009). Total operative times were comparable (median, 293 minutes; interquartile range, 222-411 minutes) for axillary versus (298 minutes; interquartile range, 231-368 minutes) for innominate (P for superiority = .47). Stroke/transient ischemic attack occurred in 4 (7.1%) participants in the axillary versus 2 (3.6%) in the innominate group (P = .43). Thirty-day mortality, seizures, delirium, and duration of mechanical ventilation were similar in both groups. CONCLUSIONS: diffusion-weighted magnetic resonance imaging assessments indicate that antegrade cerebral protection with innominate cannulation is safe and affords similar neuroprotection to axillary cannulation during aortic surgery, although the burden of new neurological lesions is high in both groups.

The Ross procedure in patients older than 50: A sensible proposition?

BACKGROUND: The Ross procedure offers several advantages in nonelderly adults; however, the optimal age cutoff remains undetermined. The aim of this study was to compare the safety and mid-term outcomes after the Ross procedure in adult patients age ≤50 years and those age >50 years. METHODS: Between 2011 and 2019, 497 consecutive patients (mean age, 47 ± 12 years; 73% male) underwent a Ross procedure in 5 Canadian centers and were followed prospectively. Of these patients, 232 (47%) were age >50 years (mean, 57 ± 4 years) and 265 (53%) were age ≤50 years (mean, 38 ± 10 years). Early and mid-term outcomes were compared between the 2 groups. RESULTS: Patients age >50 years had more comorbidities: diabetes (14% vs 4%; P < .01), chronic obstructive pulmonary disease (8% vs 2%; P < .01), and coronary artery disease (17% vs 3%; P < .01). In contrast, patients age ≤50 years had more redo surgeries (24% vs 8%; P < .01), pure aortic regurgitation (21% vs 6%; P < .01) and unicuspid valves (42% vs 9%; P < .01). In-hospital mortality was similar in the 2 groups (0.4% vs 0.4%; P = .99). There were no between-group differences in perioperative complications. The cumulative incidence of reintervention was similar at 6 years (>50 years: 0.7 ± 0.7%; ≤50 years: 4 ± 2%; P = .12). Survival at 6 years was 98 ± 2% in patient age >50 years versus 96 ± 2% in those age ≤50 years (P = .43), similar to the age- and sex-matched general population. CONCLUSIONS: The Ross procedure is a safe operation in patients age >50 years and provides excellent hemodynamics, stable valve function, and restored survival at mid-term follow-up. In expert centers, it should be considered as an alternative in selected patients age >50 years.

Frozen Elephant Trunk for Aortic Arch Reconstruction is Associated with Reduced Mortality as Compared to Conventional Techniques.

To examine the perioperative outcomes following aortic arch repair using frozen elephant trunk (FET) vs conventional elephant trunk (ET) techniques. Between 2002 and 2018, 390 patients underwent aortic repair with elephant trunk reconstruction at 9 centers: 172 patients received a FET (mean age: 65+/-13 years, 30% female, 37% aortic dissection) and 218 patients received an ET (mean age: 63+/-13 years, 37% female, 43% aortic dissection). Outcomes of interest included in-hospital mortality; stroke; and spinal cord injury (SCI). In-hospital mortality rate was 11% (n = 43) overall, 9% (n = 15) for FET and 13% (n = 28) for ET. Post-operative stroke occurred in 13% (n = 49) overall, 13% (n = 22) for FET and 12% (n = 27) for ET. The rate of post-operative SCI was 3% (n = 13) overall, 5.0% (n = 9) for FET and 2.0% (n = 4) for ET. When compared to ET, the propensity score analysis confirmed FET to be associated with lower mortality (adjusted risk difference -7.0% (95% CI -13.0 to -1.0), P = 0.02). There was no significant difference in the propensity score-adjusted risk difference for stroke between FET and ET (-0.7%, 95% CI -7.4% to 6.1%, P = 0.85), nor for SCI (3.3%, 95% CI -0.4% to 7.0%, P = 0.085) On multivariable analysis, FET was associated with lower odds of mortality (OR 0.44, 95% CI 0.21-0.95, P = 0.04), and had similar odds of stroke (OR 0.83, 95% CI 0.41-1.70, P = 0.62) and SCI (OR 2.83, 95% CI 0.83-9.60, P = 0.1). FET repair is associated with lower in-hospital mortality as compared to conventional ET, and results in similar risk of stroke and spinal cord injury. Further investigation is warranted.