Cerebrovascular imaging of cerebral ischemia in acute type A aortic dissection

Extra-anatomic revascularization and a new cannulation strategy for preoperative cerebral malperfusion due to severe stenosis or occlusion of supra-aortic branch vessels in acute type A aortic dissection

Objectives

Acute type A aortic dissection (ATAAD) with severe stenosis or occlusion of the true lumen of aortic arch branch vessels often leads to an increased incidence of severe postsurgical neurological complications and mortality rate. In this study, we aimed to introduce our institutional extra-anatomic revascularization and cannulation strategy with improved postoperative outcomes for better management of patients with cerebral malperfusion in the setting of ATAAD.

Methods

Twenty-eight patients with ATAAD complicated by severe stenosis or occlusion of the aortic arch branch vessels, as noted on combined computed tomography angiography of the aorta and craniocervical artery, between January 2021 and June 2022 were included in this study. Basic patient characteristics, surgical procedures, hospitalization stays, and early follow-up results were analyzed.

Results

The median follow-up duration was 16.5 months (interquartile range: 11.5-20.5), with a 100% completion rate. The 30-day mortality rates was 7.1% (2/28 patients); two patients had multiple cerebral infarctions on preoperative computed tomography and persistent coma. Postoperative transient neurological dysfunction occurred in 10.7% (3/28) of the patients, and no new permanent neurological dysfunction occurred. Of all the patients, 3.6% (1/28) had novel acute renal failure. No other deaths, secondary surgeries, or serious complications occurred during the early follow-up period.

Conclusions

Use of extra-anatomic revascularization and a new cannulation strategy before cardiopulmonary bypass is safe and feasible and may reduce the high incidence of postoperative neurological complications in patients with ATAAD and cerebral malperfusion.

Cerebral infarction and risk factors in acute type A aortic dissection with arch branch extension

OBJECTIVE

Stanford type A aortic dissection (AAD) may affect the supra-aortic arteries, which are associated with acute ischemic stroke (AIS) or transient ischemic attack (TIA). This study aimed to investigate cerebral perfusion, the infarction incidence and risk factors in AAD patients.

METHODS

A total of 156 consecutive AAD patients were enrolled and divided into two groups according to whether the aortic arch branches were involved: the affected group (n = 90) and the unaffected group (n = 66). Clinical, echocardiographic/carotid Doppler data and cerebral infarction morbidity were compared between the groups. Independent predictors of 30-day AAD mortality were identified through multivariable Cox regression, and perioperative risk factors were analyzed.

RESULTS

In total, 57.7% of AAD patients had aortic arch branch involvement. Abnormal Doppler waveforms were more common in the affected group (p < 0.05). Regarding intracranial perfusion, the blood flow volumes (BFVs) of the bilateral internal carotid arteries (ICAs) and right vertebral artery (RVA) in the affected group were significantly reduced (p < 0.05). The incidence of cerebral infarction in the affected group was significantly higher than that in the unaffected group (35.6% vs. 19.7%, p = 0.031). Multivariable analysis revealed that age >45 years old, right internal carotid artery (RICA) involvement and reduced left ventricular ejection fraction (LVEF) were significant predictors of perioperative death.

CONCLUSIONS

Aortic arch branch involvement is common in patients with AAD and is associated with reduced cerebral blood flow (especially on the right side) and a higher incidence of cerebral infarction. Age, extension of the RICA dissection and LVEF impairment are independent risk factors for AAD-related death.

Preoperative neurological dysfunctions: what is their meaning in patients presenting with acute type A aortic dissection?

INTRODUCTION

Type A aortic dissection (AAD) is a life-threatening disease with very high mortality. The gold standard treatment is surgical, as medical treatment has been proven to be ineffective. It is still unclear the role of preoperative neurological dysfunction in the prognosis of the patient. Therefore, the choice of performing surgery in patients with neurological symptoms is still left to the surgeon at the time of the diagnosis. The aim of this study is to make a narrative review of the current literature about the management of patients with neurological symptoms in AAD patients.

EVIDENCE ACQUISITION

A bibliographical research was performed on PubMed, looking for papers containing the words: "((preoperative neurological symptoms in type a aortic dissection) OR brain injury type A aortic dissection) AND ("2010"[Date - Publication]: "3000"[Date - Publication])". A total of 35 papers were found.

EVIDENCE SYNTHESIS

A total of 6 papers were chosen to be reviewed. All of them concluded that even patients with severe neurological symptoms (up to comatose state) had a good chance to recover neurological functions after surgery if treated in the first hours from the onset of symptoms. Interestingly, a hemorrhagic stroke was rarely found.

CONCLUSIONS

Preoperative neurological dysfunction have been long considered a contraindication to surgery. Nevertheless, several authors show neurological and survival good results in patients with preoperative neurological dysfunction. They also stress the importance of surgical timing finding in 5 to 10 hours the surgical time limit to improve neurological dysfunction. A preoperative neurological dysfunction could be considered a strong advice towards surgical intervention. It is time to change and consider prompt surgery not only for survival but also for cerebral protection.

Clinical analysis of aortic dissection with sudden coma and paraplegia as the main symptoms

Objective

This study aimed to investigate the clinical characteristics of patients with aortic dissection presenting with neurological symptoms as the initial symptoms.

Methods

Clinical characteristics, radiological abnormalities, and prognosis were analyzed in two female patients with aortic dissection. The main clinical symptoms were sudden coma and paraplegia. A detailed clinical examination was performed and computed tomography scans were evaluated.

Results

The initial symptoms of the patients involved the nervous system. Chest and abdominal computed tomography scans were performed to confirm the diagnosis of aortic dissection. Both patients died.

Conclusion

Patients who present with nervous system symptoms as the first symptoms of aortic dissection, which lead to misdiagnosis and missing the diagnosis, are rare. Improvement in the understanding of this disease is required to ensure that patients receive a timely diagnosis in the early stages.

Carotid Artery Stenting for the Treatment of Fatal Acute Cerebral Infarction Associated with Aortic Dissection

Acute aortic dissection (AAD) complicated with acute cerebral infarction lacks a unified treatment plan. We report probably the most effective treatment of a type A AAD with acute cerebral infarction leading to coma. A 43-year-old man presented with acute hemiplegia and unconsciousness. He was diagnosed as acute cerebral infarction. After an ineffective emergency intravenous thrombolysis, a Digital Subtraction Angiography (DSA) examination revealed the severe cerebral artery occlusion, and the TICI 3 level was achieved by stent implantation in the left common carotid artery with significant neurological recovery. A type A AAD was found at the 1 month follow-up ultrasound examination and a further thoracic surgery was performed successfully. Carotid ultrasound is helpful for the diagnosis of AAD from acute cerebral infarction. Carotid artery stenting followed by thoracic surgery is effective in this kind of emergency situations. Further studies are needed to determine the exact indications.

Acute ischemic stroke as a complication of Stanford type A acute aortic dissection: a review and proposed clinical recommendations for urgent diagnosis

BACKGROUND

Stanford type A acute aortic dissection requires emergency surgery. Because patients with ischemic stroke as a complication of Stanford type A acute aortic dissection do not often complain of chest or back pain, probably due to consciousness disturbance, amnesia, or aphasia, a fatal course following inappropriate intravenous rt-PA therapy and delay of appropriate surgical treatment sometimes occur.

REVIEW AND PROPOSED RECOMMENDATIONS

When treating any suspected stroke patients, emergency services and initial urgent care doctors should always suspect aortic dissection. Even in the absence of chest or back pain, the initial urgent care doctor needs to immediately perform chest contrast CT if suspecting aortic dissection from blood pressure laterality or upper mediastinal widening on chest X-ray. Whenever aortic dissection cannot be ruled out from initial clinical information, the initial urgent care doctor should evaluate the common carotid artery (CCA). Dissection extension to the CCA or flow abnormality of the CCA is often detected if aortic dissection is a cause of ischemic stroke or transient ischemic attack. Head CT or MRI including vascular imaging is preferable. D-dimer should be measured in hospitals where available. As soon as aortic dissection is identified, the initial urgent care doctor needs to consult with cardiovascular surgeons or cardiologists for appropriate treatment.