Faculty Bibliography

OBJECTIVE:This study evaluated the frequency and clinical impact of thromboembolic complications after frozen elephant trunk aortic arch repair using the Thoraflex device (Terumo Aortic). METHODS:A total of 128 consecutive patients (mean age 67.9 ± 13.7 years, 31.0% female) underwent frozen elephant trunk aortic arch repair using the Thoraflex device between September 2014 and May 2021 in 4 Canadian centers. Patient baseline characteristics, intraoperative details, and frozen elephant trunk thromboembolic complications were collected retrospectively and analyzed. RESULTS:Fifteen patients (11.7%) had thrombus visualized within the frozen elephant trunk stent graft on imaging (n = 8; 53.3%) or had a thromboembolic event (n = 9; 60.0%) before hospital discharge. Sites of embolism were mesenteric (n = 8; 88.9%), renal (n = 4; 44.4%), and iliofemoral (n = 1; 11.1%). Patients who experienced thromboembolic complications were more likely to have a history of autoimmune disease (n = 3; 20.0% vs n = 2; 1.8%; P = .01) and implantation of a longer frozen elephant trunk stent graft (150 mm vs 100 mm) (n = 13; 86.7% vs n = 45; 39.8%; P < .001). All patients with thromboembolic complications received therapeutic anticoagulation, and a smaller proportion required an open surgical (n = 5; 33.3%) or an endovascular (n = 2; 13.3%) intervention. Radiographic resolution of thromboembolic complications was observed in 86.7% of patients (n = 13). In-hospital mortality occurred in 1 patient, stroke occurred in 1 patient, and transient spinal cord injury occurred in 1 patient. CONCLUSIONS:Thromboembolic complications occur more often than previously recognized after frozen elephant trunk aortic arch repair using the Thoraflex device and are associated with increased rates of surgical and endovascular reintervention. Prevention and management of these complications require further study.

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.

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.

BACKGROUND:Acute kidney injury (AKI) after repair of type A acute aortic dissection (TAAAD) has been shown to affect both short- and long-term outcomes. This study aimed to validate the impact of postoperative AKI on in-hospital and long-term outcomes in a large population of dissection patients presenting to multinational aortic centers. Additionally, we assessed risk factors for AKI including surgical details. METHODS:Patients undergoing surgical repair for TAAAD enrolled in the International Registry of Acute Aortic Dissection database were evaluated to determine the incidence and risk factors for the development of AKI. RESULTS:A total of 3307 patients were identified. There were 761 (23%) patients with postoperative AKI (AKI group) vs 2546 patients without (77%, non-AKI group). The AKI group had a higher rate of in-hospital mortality (n = 193, 25.4% vs n = 122, 4.8% in the non-AKI group, P < .001). Additional postoperative complications were also more common in the AKI group including postoperative cerebrovascular accident, reexploration for bleeding, and prolonged ventilation. Independent baseline characteristics associated with AKI included a history of hypertension, diabetes, chronic kidney disease, evidence of malperfusion on presentation, distal extent of dissection to abdominal aorta, and longer cardiopulmonary bypass time. Kaplan-Meier survival curves revealed decreased 5-year survival among the AKI group (P < .001). CONCLUSIONS:AKI occurs commonly after TAAAD repair and is associated with a significantly increased risk of operative and long-term mortality. In this large study using the International Registry of Acute Aortic Dissection database, several factors were elucidated that may affect risk of AKI.

BACKGROUND:to investigate the frequency and distribution of new ischemic brain lesions detected by diffusion-weighted imaging on brain magnetic resonance imaging after aortic arch surgery. METHODS:This preplanned secondary analysis of the randomized, controlled ACE (Aortic Surgery Cerebral Protection Evaluation) CardioLink-3 trial compared the safety and efficacy of innominate versus axillary artery cannulation during elective proximal aortic arch surgery. Participants underwent pre and postoperative magnetic resonance imaging. New ischemic lesions were defined as lesions visible on postoperative, but not preoperative diffusion weighted imaging. RESULTS:=0.06) were associated with greater number of lesions. CONCLUSIONS:In patients who underwent elective proximal aortic arch surgery, new ischemic brain lesions were common, and predominantly involved the middle cerebral artery territory or cerebellum. Underlying small vessel disease, lower temperature nadir during surgery, and advanced age were risk factors for perioperative ischemic lesions. REGISTRATION:URL: https://www. CLINICALTRIALS:gov; Unique identifier: NCT02554032.

PURPOSE OF REVIEW:The burden of tricuspid regurgitation (TR) is high in the aging population, almost 4% in the age group over 75 have moderate or more TR. This carries a poor prognosis and an increased incidence of mortality, prolonged hospitalization, and rehospitalization in symptomatic patients with severe TR is observed. Percutaneous tricuspid valve intervention has emerged as a viable therapeutic option, with an increasingly large toolbox of both tricuspid repair and replacement devices. The optimal strategy, timing and patient selection for transcatheter intervention are yet to be determined. This review focuses on the current strengths and limitations of transcatheter tricuspid repair vs. replacement, drawing on lessons learned from surgery. RECENT FINDINGS:Early outcome studies have been published in the last 2 years for many of the new percutaneous tricuspid valve devices. We have summarized these results and compared them to surgical tricuspid valve repair and replacement. We found that surgical data shows a tendency to better outcome with tricuspid valve repair compared to replacement. For transcatheter interventions studies comparing repair and replacement are lacking but both interventions show good procedural success rates and are efficient in reducing the grade of tricuspid regurgitation. SUMMARY:Transcatheter tricuspid valve interventions offer a safe and effective alternative to tricuspid surgery or medical therapy. The decision between valve replacement and repair should be based on patient anatomy, operator experience and device availability until head-to-head comparison of different devices are available.

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.