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

Analysis of the effect of mild hypothermic circulatory arrest anesthesia on postoperative lung function in patients with aortic dissection

This study aims to explore the effect of mild hypothermic circulatory arrest anesthesia on postoperative lung function in patients with aortic dissection (AD). A total of 71 patients who underwent modified aortic arch replacement surgery in hospitals from January 2021 to December 2023 were selected as the study subjects. According to the differences in rectal temperature and mild hypothermia circulatory arrest temperature during surgery, patients were divided into mild hypothermia group and moderate hypothermia group. The intraoperative surgery time, infusion status, and postoperative complications of patients were compared from 3 dimensions: preoperative, intraoperative, and postoperative. The differences between 2 groups of patients under different anesthesia methods were evaluated. The general situation of preoperative grouping for patients in the mild hypothermia group and the moderate hypothermia group was basically the same, and there was no significant difference, indicating a certain degree of comparability. In the comparison of intraoperative surgery time, the surgery time, cardiopulmonary bypass time, cooling time, and rewarming time of the mild hypothermia group were (406.41 ± 35.14) min, (147.75 ± 22.58) min, (15.87 ± 6.78) min, and (70.45 ± 9.48) min, respectively, with P < .05 between the mild hypothermia group and the moderate hypothermia group. Starting from the second day after surgery and by the third day, there were a significant difference in the patient's respiratory index and oxygenation index (P < .05). There were significant postoperative changes in alanine lminotransferase, total bilirubin, and creatinine levels in both groups. On the third day after surgery, there was a significant difference in the levels of alanine lminotransferase and total bilirubin between the shallow hypothermia group and the moderate hypothermia group, with statistical significance (P < .05). Compared to the group of moderate to low temperature circulatory arrest modes, shallow low temperature circulatory arrest anesthesia is safer and more effective in the treatment of Stanford type A AD patients, and has better therapeutic effects on long-term postoperative lung function recovery in AD patients. This method can not only shorten the cardiopulmonary bypass time and hospitalization time, but also improve the postoperative recovery of patients.

Role of Helicopter Transfer and Cloud-Type Imaging for Acute Type A Aortic Dissection

BACKGROUND

 This study explored if long-distance transfer was safe for patients suffering from acute aortic dissection type A (AADA) and also analyzed the effectiveness of helicopter transfer and cloud-type imaging transfer systems for such patients in northern Hokkaido, Japan.

METHODS AND RESULTS

 The study included 112 consecutive patients who underwent emergency surgical treatment for AADA from April 2014 to September 2020. The patients were divided into two groups according to the location of referral source hospitals: the Asahikawa city group (group A, n = 49) and the out-of-the-city group (group O, n = 63). Use of helicopter transfer (n = 13) and cloud-type telemedicine (n = 20) in group O were reviewed as subanalyses.Transfer distance differed between groups (4.2 ± 3.5 km in group A vs 107.3 ± 69.2 km in group O; p = 0.0001), but 30-day mortality (10.2% in group A vs 7.9% in group O; p = 0.676) and hospital mortality (12.2% in group A vs 9.5% in group O; p = 0.687) did not differ. Operative outcomes did not differ with or without helicopter and cloud-type telemedicine, but diagnosis-to-operation time was shorter with helicopter (240.0 ± 70.8 vs 320.0 ± 78.5 minutes; p = 0.031) and telemedicine (242.0 ± 75.2 vs 319.0 ± 83.8 minutes; p = 0.007).

CONCLUSION

 We found that long-distance transfer did not impair surgical outcomes in AADA patients, and both helicopter transfer and cloud-type telemedicine system could contribute to the reduction of diagnosis-to-operation time in the large Hokkaido area. Further studies are mandatory to investigate if both the systems will improve clinical outcomes.

Case Report: Successful endovascular treatment of acute type A aortic dissection

Introduction

Open surgical repair remains the current gold standard for the treatment of acute type A aortic dissection. However, especially elderly patients with relevant comorbidities who are deemed unfit for open surgery may benefit from a minimally invasive endovascular approach.

Methods

We report a case of an 80-year-old male with retrograde acute type A aortic dissection and peripheral malperfusion after receiving thoracic endovascular aortic repair due to thoracic aortic aneurysm. Our individualized endovascular approach consisted of left carotid-subclavian bypass, proximal extension of thoracic endovascular aortic repair using a covered stent graft and a single covered stent graft for the ascending aorta in combination with an uncovered stent for the aortic arch.

Results

Postoperative computed tomographic angiography demonstrated excellent outcome with no signs of endoleak or patent false lumen. Follow-up after 3.5 years showed a stable result with no signs of stent failure or dissection progress. No aortic re-interventions were needed in the further course.

Discussion

An individualized endovascular approach may be justified for acute type A aortic dissection in elderly patients with high surgical risk if performed in specialized aortic centers. Additional short-length stent graft devices are needed to address the anatomical challenges of the ascending aorta. For enhanced remodeling of the dissected aorta, the use of an additional uncovered stent may be advisable.

The impact of malperfusion patterns in elderly patients undergoing surgery for acute type A aortic dissection

OBJECTIVES

The aim of this study is to investigate the outcome of elderly patients with surgically treated acute type A aortic dissection (ATAAD) complicated by malperfusion.

METHODS

Patients ≥70 years old who underwent surgical treatment for ATAAD between January 2000 and December 2020 were enrolled in this study and stratified by their specific Penn Classification into 4 different subgroups, where Penn Abc was defined as multilevel malperfusion. Short- and long-term outcomes were investigated. Multivariable binary logistic regression was performed to identify risk factors for 1-year mortality.

RESULTS

Four hundred elderly patients underwent surgical treatment for ATAAD. A total of 204 (51%) patients had no evidence of malperfusion (Penn Aa), 106 (26.5%) had localized organic malperfusion (Penn Ab), 44 (11%) patients had systemic malperfusion (Penn Ac) and 46 (11.5%) suffered from multilevel malperfusion (Penn Abc). For the latter, in-hospital mortality was 70% (P < 0.001). Age (P < 0.006) and multilevel malperfusion (P < 0.001) were independent risk factors for 1-year mortality. Patients with multilevel malperfusion showed the worst 1-year survival (P < 0.001). In the case of Penn Aa, in-hospital mortality was 13% (P < 0.001).

CONCLUSIONS

Surgery may lead to satisfactory results in the absence of malperfusion, even in octogenarians. Elderly patients with multilevel malperfusion show very poor surgical outcome. In these patients, the decision for surgery should be taken with caution. Operation, if performed, should be carried out by experienced teams only.

Acute Lung Injury in aortic dissection : new insights in anesthetic management strategies

Acute aortic dissection (AAD) is a severe cardiovascular disease characterized by rapid progress and a high mortality rate. The incidence of acute aortic dissection is approximately 5 to 30 per 1 million people worldwide. In clinical practice, about 35% of AAD patients are complicated with acute lung injury (ALI). AAD complicated with ALI can seriously affect patients' prognosis and even increase mortality. However, the pathogenesis of AAD combined with ALI remains largely unknown. Given the public health burden of AAD combined with ALI, we reviewed the anesthetic management advances and highlighted potential areas for clinical practice.

Cerebral Protection Strategies and Stroke in Surgery for Acute Type A Aortic Dissection

Background: Perioperative stroke remains a devastating complication in the operative treatment of acute type A aortic dissection. To reduce the risk of perioperative stroke, different perfusion techniques can be applied. A consensus on the preferred cerebral protection strategy does not exist. Methods: To provide an overview about the different cerebral protection strategies, literature research on Medline/PubMed was performed. All available original articles reporting on cerebral protection in surgery for acute type A aortic dissection and neurologic outcomes since 2010 were included. Results: Antegrade and retrograde cerebral perfusion may provide similar neurological outcomes while outperforming deep hypothermic circulatory arrest. The choice of arterial cannulation site and chosen level of hypothermia are influencing factors for perioperative stroke. Conclusions: Deep hypothermic circulatory arrest is not recommended as the sole cerebral protection technique. Antegrade and retrograde cerebral perfusion are today’s standard to provide cerebral protection during aortic surgery. Bilateral antegrade cerebral perfusion potentially leads to superior outcomes during prolonged circulatory arrest times between 30 and 50 min. Arterial cannulation sites with antegrade perfusion (axillary, central or carotid artery) in combination with moderate hypothermia seem to be advantageous. Every concept should be complemented by adequate intraoperative neuromonitoring.

Time is of the essence: where can we improve care in acute aortic dissection?

OBJECTIVES

In acute aortic dissection type A various components of the diagnostic and logistic pathways may affect the time to definitive treatment. This study aimed to characterize these components and to identify factors delaying the optimal management within our institutional referral network.

METHODS

Between January 2017 and January 2020, 96 consecutive patients with classical aortic dissection type A were admitted (28%) or referred (72%) to our tertiary care centre and analysed retrospectively. Data are presented as medians (25th-75th quartile).

RESULTS

Median age was 66 years (56-74), 63% were male. Most of the patients were primarily admitted to a cardiology department (40%), whereas about a fourth were admitted to departments for internal medicine (26%) and general surgery (27%). The median interval from the onset of symptoms to hospital admission was 2.1 (1-4.4) h. From admission to confirmed diagnosis it took 2.1 (0.6-9.5) h and the median interval from confirmed diagnosis to admission at our specialized tertiary care aortic centre was 1.5 (0.9-2.4) h. Following admission to our centre, 1.1 (0.5-1.9) h passed until the induction of anaesthesia and 0.8 (0.0-1.1) h until the start of surgery. The total interval from the onset of symptoms to the start of surgery was 7.6 h (5.1-12.3).

CONCLUSIONS

The marked variability of the time from symptoms to diagnosis at any medical facility demonstrates the importance of awareness in the optimization of the treatment of acute aortic dissection type A.

State of the Art Review: Surgical Treatment of Acute Type A Aortic Dissection

Acute type A aortic dissection (ATAAD) is a life-threatening event that requires immediate surgical treatment. Improvements in surgical treatment, graft technology, organ protection and imaging techniques have led to improved clinical outcomes. Individualized treatment concepts have emerged based on more advanced planning tools that allow for a tailored approach even in complex situations such as multi-level malperfusion. This review provides an overview of the current surgical treatment of ATAAD, focusing on new disease classifications, preoperative computed tomography angiography (CTA) assessment, new prosthesis and stent technologies, and organ-protection strategies.