A systematic approach to improve the outcomes of type A aortic dissection

Inconsistent False Lumen Enhancement Predicts Late Aortic Events After Hemiarch Replacement in Acute Type A Aortic Dissection

The impact of inconsistent enhancement within the patent false lumen on the occurrence of late aortic events remains uncertain. We enrolled 55patients who exhibited a patent false lumen after hemiarch replacement. The Hounsfield unit (HU) measurements in the patent false lumen were obtained at 2 specific locations: the aortic arch (a) and the descending aorta (b). The false lumen HU score was calculated as the absolute value of 1 - a/b, representing the discrepancy in HUs within the patent false lumen. We investigated the cut-off value of the false lumen HU score with the receiver operating characteristics curve to predict the incidence of late aortic events. We divided the patients based on the cut-off value and compared the cumulative incidence of the late aortic events. The analysis of the receiver operating characteristics curve showed that the cut-off value of the false lumen HU score was 0.345. Based on this cut-off value, we divided them into 2 groups: Group A (score <0.345, n = 26) and Group B (score ≥0.345, n = 29). The baseline characteristics were similar between the 2 groups. The cumulative incidence of the late aortic events was significantly lower in Group A (7.8% at 5 years) than in Group B (39.9% at 5 years) (p = 0.02). The false lumen HU score might be useful to predict the incidence of late aortic events after hemiarch replacement.

FL% is associated with the severity of acute DeBakey type I aortic dissection in patients undergoing frozen elephant trunk and total arch replacement

Objectives

The diameter, area, and volume of the true lumen and false lumen (FL) have been measured in previous studies to evaluate the extent of DeBakey type I aortic dissection. However, these indicators have limitations because of the irregular shapes of the true and false lumens and the constant oscillation of intimal flap during systole and diastole. The ratio of arch lengths seems to be a more reliable indicator. FL% was defined as the ratio of the arch length of FL to the circumference of the aorta at the different levels of the aorta. The purpose of this article was to investigate whether FL% is a predictor of the severity of acute DeBakey type I aortic dissection in patients undergoing frozen elephant trunk (FET) and total arch replacement.

Methods

In this retrospective observational study, we analyzed a total of 344 patients with acute DeBakey type I aortic dissection that underwent FET and total arch replacement at our center from October 2015 to October 2019. The patients were divided into two groups by cluster analysis according to the perioperative course. Binary logistic regression analyses were performed to determine whether FL% could predict the severity of acute DeBakey type I aortic dissection. The area under the receiver operating characteristic curve (AUROC) was used to assess the power of the multivariate logistic regression model for the severity of acute DeBakey type I aortic dissection.

Results

The patients in the ultra-high-risk group (109 patients) had significantly more severe clinical comorbidities and complications than the patients in the high-risk group (235 patients). The ascending aortic FL% [odds ratio (OR), 11.929 (95% CI: 1.421-100.11); P = 0.022], location of initial tear [OR, 0.68 (95% CI: 0.47-0.98); P = 0.041], the degree of left iliac artery involvement [OR, 1.95 (95% CI: 1.15-3.30); P = 0.013], and the degree of right coronary artery involvement [OR, 1.46 (95% CI: 1.01-2.12); P = 0.045] on preoperative computed tomography angiography were associated with the severity of acute DeBakey type I aortic dissection. The AUROC value of this multivariate logistic regression analysis was 0.940 (95% CI: 0.914-0.967; P < 0.001). The AUROC value of ascending aortic FL% was 0.841 (95% CI: 0.798-0.884; P < 0.001) for the severity of acute DeBakey type I aortic dissection in patients undergoing FET and total arch replacement.

Conclusions

Ascending aortic FL% was validated as an essential radiologic index for assessing the severity of acute DeBakey type I aortic dissection in patients undergoing FET and total arch replacement. Higher values of ascending aortic FL% were more severe.

Anatomic feasibility of a modular Endo-Bentall stent graft system for type A aortic dissection

OBJECTIVE

The implementation of thoracic endovascular aortic repair in patients with type A aortic dissection has been strictly constrained due to the pulsatile movement and distensibility and the insufficient length of landing zones on ascending aorta. The most prevalent anatomical limitation is the insufficient length of proximal and distal landing zones. We propose a modularly designed Endo-Bentall stent graft system to broaden the scope of thoracic endovascular aortic repair in the ascending aorta by covering intimal tears in the aortic root and ascending aorta and reconstructing coronary arteries. This study was conducted to assess the anatomical feasibility of a novel stent graft design.

METHODS

In this study, we included 152 patients with type A aortic dissection for image measurement and analysis. All computed tomography angiography images were assessed on a 3mensio Workstation version 10.2 (3mensio Medical Imaging B.V.) utilizing the centerline method. We compared the diameters and lengths at various planes in relation to the proposed anatomical criteria for the modular Endo-Bentall stent graft system.

RESULTS

The patients were predominantly male (67.1%), with a median age of 56.5 years (interquartile range, 50.0-65.0 years). Among all aortic dissections, 91.5% extended proximally to the sinotubular junction, whereas only 8.6% were restricted to the tubular ascending aorta. The median perimeter-derived diameter of the aortic annulus was 24.1 mm. The median maximum aortic diameter at the sinotubular junction and brachiocephalic trunk were 44.6 mm and 43.5 mm, respectively. The median height of the left coronary artery, right coronary artery, and sinus of Valsalva were 12.7 mm, 16.7 mm, and 28.4 mm, respectively. After applying exclusion criteria, 66.4% of all patients were anatomically eligible for the modular Endo-Bentall stent graft system. A total of 85.1% of patients were suitable for stent grafts with lengths of 70 mm, 80 mm, or 90 mm. Both antegradely and retrogradely tapered stent grafts were required, according to the diameter differences between the STJ and brachiocephalic trunk.

CONCLUSIONS

Utilizing the modular Endo-Bentall stent-graft design, approximately two-thirds of patients with type A aortic dissection are anatomically eligible for endovascular repair. Further animal studies are required to optimize the device design.

Contemporary utilization of the axillary artery in cardiac surgery

INTRODUCTION

The axillary artery is a reliable inflow vessel when addressing pathology of the aortic root and aortic arch that may preclude standard central cannulation strategies. This narrative review examines the use of the axillary artery in cardiac surgery. Anatomy, indications for use, cannulation strategies, and potential complications will be discussed.

METHODS

A comprehensive review of the current literature was performed using PubMed, Cochrane Review, and authoritative committee guidelines. A narrative review incorporating current available evidence was undertaken.

COMMENT

Use of the axillary artery in select cardiac surgical cases is reliable, reproducible, and may be preferable in certain cases involving ascending aortic pathology, reoperative surgery, porcelain aorta, access for transcatheter valve therapies, and peripheral mechanical circulatory support.

Toward standard abbreviations and acronyms for use in articles on aortic disease

Objectives

Academic medical literature is fraught with complex article-specific acronyms and abbreviations that can impair communication and make reading arduous. Our goal is to ease frustration with bespoke, inconsistent, and variable sets of abbreviations that currently exist for common aorta-related terminology (eg, anatomy, imaging, disease, and therapy). We hope to ease reading and improve communication in the aortic sphere of cardiovascular literature.

Methods

We reviewed a total of 205 published references related to aortic disease, including a systematic review of aorta-related articles in the Journal of Thoracic and Cardiovascular Surgery from the years 2020 and 2021. The array of variable definitions, abbreviations, and acronyms encountered in different papers that refer to the same terminology was striking, revealing that there were few standardized abbreviations in the aortic literature. We cataloged these terms, their associated abbreviations, and their frequency of use, and compiled a list of proposed standard abbreviations for commonly used terms that could be implemented uniformly in articles written about aortic diseases.

Results

We present suggested acronyms and abbreviations for common terminology related to the aorta. It is anticipated that this standard list will evolve over time as the literature and technology of the field grows and develops.

Conclusions

A proposed standard set of acronyms and abbreviations for aorta-related terminology is provided that, if found useful, could be implemented broadly in the aortic literature.

Comparing short-term/long-term outcomes of heart transplants that occur inside and outside of normal working hours

Aims

Heart transplantation involves many factors such as donor selection, recipient management, multidisciplinary assessment, coordination with other organ teams, and transportation. Because of some unpredictable factors, heart transplantation can be conducted at any time of day. The purpose of this study is to investigate if outcomes differ between heart transplants taking place inside or outside of normal working hours.

Methods and results

We reviewed patients who underwent heart transplantation at our institution from January 2010 to July 2020 (n = 329). Based on the documented start time of the recipient surgeries, the cohort was divided into two groups: working hours (Group A: 7:30 to 17:00; n = 92) and after hours (Group B: 17:00 to 7:30; n = 237). We compared these groups using propensity score matching analysis. After propensity score matching, 78 pairs of patients were successfully matched. We reviewed early and late clinical outcomes including survival. Long‐term survival was compared using the Kaplan–Meier method. In the propensity‐score matched patients, there were no significant differences in the baseline characteristics between two groups. In‐hospital mortality was not significantly different between the two groups (Group A: 6.4% vs. Group B: 2.6%, P = 0.44). Ischaemic time and cross‐clamp time did not differ between the groups. In terms of postoperative complications, there were no significant differences between two groups in stroke (6.4% vs. 3.9%, P = 0.72), primary graft dysfunction requiring extracorporeal membrane oxygenation (5.1% vs. 7.7%, P = 0.75), re‐exploration for bleeding (9.0% vs. 12.8%, P = 0.44), and newly required haemodialysis (7.7% vs. 6.4%, P = 0.75). The survival rate in Group A (88.1% at 1 year, 81.3% at 3 years) was not significantly different from Group B (90.5% at 1 year, 82.3% at 3 years, log rank = 0.96).

Conclusion

There was no significant difference in clinical outcomes between heart transplants taking place inside or outside of working hours. A high quality of care can be provided for heart transplant patients even during after hours.

An Incident of a Massive Pulmonary Embolism Following Acute Aortic Dissection. a Case Report

Acute aortic dissection and acute pulmonary embolism are two life-threatening emergencies. The presented case is of an 81-year-old man who has been diagnosed with an acute Stanford type A aortic dissection and referred to a tertiary hospital for surgical treatment. After a successful aortic repair and an overall favourable postoperative recovery, he was diagnosed with cervical and upper extremity deep vein thrombosis and was anticoagulated accordingly. He later presented with massive bilateral pulmonary embolism.

Cannulation strategies & circulation management in type-A aortic dissection

Type A aortic dissection most often requires emergent surgery to prevent malperfusion, stroke, and/or rupture of aorta. To achieve the structural goals of the operation, the conduct of the surgery is targeted from it inception at restoring true lumen flow. In this regard, institution of cardiopulmonary bypass and circulation management is key to allow adequate systemic flow, perfusion of brain and visceral organs and comprehensive systemic cooling to achieve circulatory arrest when needed. Different strategies have been used to establish adequate true lumen perfusion with varying success rates, with the most common still being femoral cannulation. More recently axillary and central cannulation strategies have shown satisfactory results by allowing more reliable true lumen flow. Cannulation approach should, therefore, depend on individual patient characteristics, presentation, and true lumen anatomy.

Valve-sparing aortic root replacement after type A aortic dissection repairs

OBJECTIVE

Aortic root reoperation after aortic dissection repair sometimes requires aortic root replacement. A valve-preserving technique should be applied when the aortic cusp is normal. Valve-sparing aortic root reconstruction using the reimplantation technique resolves aortic valve regurgitation, root dilatation, and pseudoaneurysm in the proximal anastomosis. Our experience in aortic root reoperation is presented.

METHODS

From January 2000 to March 2019, 26 patients underwent reoperative valve-sparing aortic root reconstruction using the reimplantation technique. The time from the initial operation to reoperation was 69.3 ± 51.6 months. Aortic root reoperation was required for a fragile wall at the previous proximal anastomosis or aortic root dilatation. We aimed to stabilize the aortic root without valve regurgitation. The native aortic cusp was aggressively preserved when nearly normal. Indications included root dilatation (n = 13), pseudoaneurysm of the previous proximal anastomosis (n = 11), and aortic valve regurgitation (n = 4).

RESULTS

There was no early postoperative mortality. Follow-up was 49 ± 47 months (range 4-161 months). The 3, 5, and 10-year survival was 88.9% ± 7.4%, 88.9% ± 7.4%, and 77.8% ± 12.2%, respectively. Freedom from recurrence of a greater than moderate degree of aortic valve regurgitation at 3, 5, and 10 years was 86.5% ± 8.9%, 86.5% ± 8.9%, and 86.5% ± 8.9%, respectively. One patient underwent aortic valve replacement for recurrent aortic valve regurgitation 15 months after the valve-sparing reoperation.

CONCLUSIONS

Midterm outcomes of reoperative valve-sparing aortic root reconstruction using the reimplantation technique and postoperative aortic valve performance were satisfactory.

Preoperative Imaging Risk Findings for Postoperative New Stroke in Patients With Acute Type A Aortic Dissection

Background: Stroke is a common postoperative complication in patients with acute type A aortic dissection (ATAAD). We aimed to explore the preoperative imaging risk findings for postoperative new stroke in patients with ATAAD.

Methods: From January 2015 to December 2018, 174 patients with ATAAD who underwent preoperative aortic computed tomography angiography (CTA) and cerebral diffusion-weighted imaging (DWI) as well as postoperative brain CT were included, and divided into DWI (+) and DWI (–) groups. Pre- and intraoperative variables were collected, and logistic regression analysis was used to determine the independent risk predictors of postoperative new stroke.

Results: The incidence of postoperative new stroke was 18.4% (32/174) in patients with ATAAD. Postoperative stroke was detected in 13 (31.0%) patients in the DWI (+) group and in 19 (14.4%) patients in the DWI (–) group with significant difference (P = 0.016). In the DWI (+) group, the lesions of the cerebral infarction located in the unilateral cerebral hemisphere and distributed more than three lobes (P = 0.007) were an independent risk factor for postoperative new stroke. Hypotension (P = 0.002), retrograde ascending aorta dissection with thrombosis of the false lumen (P = 0.010), aortic arch entry (P = 0.035), and coronary artery involvement (P = 0.001) were independent risk factors for postoperative stroke in the DWI (–) cohort.

Conclusions: Patients with ATAAD with cerebral infarction are more likely to develop postoperative new stroke; thus, a preoperative DWI examination may be necessary. DWI lesions distributed more than 3 lobes in the unilateral hemisphere suggest a high possibility of postoperative stroke. For patients with ATAAD with normal brain, particular attention should be given to the CTA findings of false lumen thrombosis, aortic arch entry, and coronary artery involvement to avoid postoperative stroke.

Rapid Response in Type A Aortic Dissection: Is There a Decisive Time Interval for Surgical Repair?

Background and Aim of the Study The objective was to evaluate whether there is a decisive time interval for patients to undergo surgery and to analyze if a rapid response in acute aortic dissection type A (AADA) affects patient selection.

Methods In 283 patients undergoing surgery for AADA, median time from onset of initial symptoms to skin incision was 6.9 hours (interquartile range [IQR], 5.0–11.7 hours). Patients were divided into three groups according to median time point of surgery (median ± 3 hours, i.e., 4–10; < 4; and >10 hours).

Results Almost 50% of patients presented in a critical preoperative state at hospital admission. Subanalysis identified patients being operated within 4 hours as an exclusive high-risk cohort (higher rates of preoperative neurologic dysfunction, tamponade, and cardiopulmonary resuscitation). Patients undergoing surgery between 4 and 10 hours showed a significantly better long-term survival (p = 0.021). Surgery within this time interval had a clear protective effect on 30-day mortality (odds ratio [OR]: 0.448. 95% confidence interval [CI]: 0.219–0.915). High age (OR: 1.037; 95% CI: 1.008–1.067), preoperative malperfusion syndrome (OR: 2.802; 95% CI: 1.351–5.811), and preoperative tamponade (OR: 2.621; 95% CI: 1.171–5.866) were factors predicting 30-day mortality.

Conclusion Rapid response in AADA interacts with the natural course of the disease resulting in an overrepresentation of critical patients. While the cohort below 4 hours represents the high-risk patients, time from symptom onset to initiation of surgery should not exceed 10 hours.

Acute type A aortic dissection - a review

Acute type A aortic dissection (ATAAD) is still one of the most challenging diseases that cardiac surgeons encounter. This review is based on the current literature and includes the results from the Nordic Consortium for Acute Type-A Aortic Dissection (NORCAAD) database. It covers different aspects of ATAAD and concentrates on the outcome of surgical repair. The diagnosis is occasionally delayed, and ATAAD is usually lethal if prompt repair is not performed. The dynamic nature of the disease, the variation in presentation and clinical course, and the urgency of treatment require significant attentiveness. Many surgical techniques and perfusion strategies of varying complexity have been described, ranging from simple interposition graft to total arch replacement with frozen elephant trunk and valve-sparing root reconstruction. Although more complex techniques may provide long-term benefit in selected patients, they require significant surgical expertise and experience. Short-term survival is first priority so an expedited operation that fits in with the surgeon's level of expertise is in most cases appropriate.

Cerebral perfusion issues in type A aortic dissection

Stroke events are very common in acute type A aortic dissection. Cerebral malperfusion could manifest at presentation due to prolonged arch vessels hypoperfusion or develop after surgery for inadequate cerebral protection during arch repair. To reduce this detrimental complication there are several adjuncts that can be adopted for cerebral protection such as direct antegrade or retrograde cerebral perfusion (RCP) and use period of deep to moderate hypothermic circulatory arrest time; however, they are often insufficient as preoperative malperfusion already caused irreversible ischemic damages. The aim of the current review article is to analyze the principal series reporting on neurological injuries during type A aortic dissection to focus on the outcomes according to the type of surgical management and identify possible predictors to better manage this complication.

Management of acute aortic dissection and thoracic aortic rupture

Background

Both acute aortic dissection and ruptured aortic aneurysm are leading causes of death in cardiovascular disease. These life-threatening conditions have recently been categorized as acute aortic syndrome. This review describes the etiology, clinical presentation, and therapeutic options for acute aortic syndrome including acute aortic dissection and ruptured aortic aneurysm.

Main body

Several diagnostic tools for detecting these critical conditions have been developed including computed tomography, ultrasonography, magnetic resonance imaging, and laboratory tests. Early and accurate diagnosis is most important to determine appropriate treatment. Initial treatment for these conditions should be aimed at controlling pain and the hemodynamic state with further treatment based on the imaging diagnosis and hematological assessment. Surgical outcomes after acute aortic syndrome are improving gradually; however, mortality remains high. Recently, thoracic endovascular aortic repair has become an alternative technique to treat complicated type B aortic dissection. Rapid treatment after early diagnosis is essential to save patients’ lives.

Conclusions

Continuous advances in imaging and treatment technologies are improving short- and long-term outcomes in patients with acute aortic syndrome. Knowledge and interest in intensive care medicine in this area are contributing to improved outcomes, and further research into this life-threatening disease will lead to improvements in diagnosis and management.