Predictors of intracranial cerebral artery stenosis in patients before cardiac surgery and its impact on perioperative and long-term stroke risk

The link between impaired oxygen supply and cognitive decline in peripheral artery disease

Although peripheral artery disease (PAD) primarily affects large arteries outside the brain, PAD is also associated with elevated cerebral vulnerabilities, including greater risks for brain injury (such as stroke), cognitive decline and dementia. In the present review, we aim to evaluate recent literature and extract information on potential mechanisms linking PAD and consequences on the brain. Furthermore, we suggest novel therapeutic avenues to mitigate cognitive decline and reduce risk of brain injury in patients with PAD. Various interventions, notably exercise, directly or indirectly improve systemic blood flow and oxygen supply and are effective strategies in patients with PAD or cognitive decline. Moreover, triggering protective cellular and systemic mechanisms by modulating inspired oxygen concentrations are emerging as potential novel treatment strategies. While several genetic and pharmacological approaches to modulate adaptations to hypoxia showed promising results in preclinical models of PAD, no clear benefits have yet been clinically demonstrated. We argue that genetic/pharmacological regulation of the involved adaptive systems remains challenging but that therapeutic variation of inspired oxygen levels (e.g., hypoxia conditioning) are promising future interventions to mitigate associated cognitive decline in patients with PAD.

Association between fasting blood glucose and intracranial cerebral artery stenosis: a secondary analysis based on a retrospective cross-sectional study in Korean adults

AIMS

Diabetes mellitus (DM) is one of the main risk factors for intracranial cerebral artery stenosis (ICAS), and fasting blood glucose (FBG) might be an effective predictor of ICAS. However, there are a few studies revealing the relationship between FBG and ICAS. We aim to identify the association between FBG and ICAS in Koreans.

METHODS

This was a secondary study based on a cross-sectional study. A total of 1011 Korean individuals who were asymptomatic but with high cerebrovascular risk underwent an examination in a Korean medical centre from March 2008 to December 2014. The main measure was FBG, while the main outcome was ICAS. Multivariate logistic regression analyses of FBG in the presence of ICAS were performed to examine the potential association. The author used the data provided by the paper "Association between Serum Alkaline Phosphatase Level and Cerebral Small Vessel Disease" for secondary analysis.

RESULTS

The average age of the participants was 64.2 ± 9.1 years old, and approximately 35% of them were males. There were 24 participants suffering from ICAS in the first FBG tertile (< 5.4 mmol/L), while there were 26 in the second tertile (5.4-7.1 mmol/L) and 50 in the third tertile (≥ 7.1 mmol/L). The non-adjusted relationship between FBG and ICAS was positive. After controlling potential confounders, the association of FPG with ICAS remained positive, as well as in subgroups analysis, such as age, sex, hypertension, diabetes mellitus, hyperlipidaemia and COAD. The association remained unchanged after adjusted sex, age, hypertension, DM, uric acid, hyperlipidaemia, and CAOD (OR = 1.08, 95% CI = 1.02-1.15). The analyses also showed that the positive association was statistically significant (P < 0.05) among individuals without diabetes.

CONCLUSIONS

This study showed a positive relationship between FBG and ICAS, which suggests that clinicians may need to be simultaneously concerned about FBG and ICAS.

Is carotid screening redundant for patients undergoing coronary artery bypass grafting?

OBJECTIVES

Stroke is a devastating complication following coronary artery bypass grafting, which thankfully occurs with low incidence. The role of preoperative carotid ultrasound remains unclear. Whilst it is a cheap and reliable way of diagnosing carotid stenosis (CS), it is unclear if and how this knowledge should impact on subsequent patient management.

METHODS

A systematic review of the literature was performed using the PRISMA guideline. A literature search was conducted on the MEDLINE database from 1950 to May 2020 using the OVID interface. Fifteen papers out of a total of 5931 were identified for inclusion.

RESULTS

The evidence overall suggests that patients with severe CS are likely to have an increased incidence of postoperative stroke-however, the prevalence of severe CS is low, and even in this cohort of patients, the incidence is not particularly high.

CONCLUSION

In screened patients identified to have severe CS, there appears to be a generally low appetite for undertaking carotid intervention internationally either before or concurrently with the coronary artery bypass grafting. Putting this all together, the widespread screening of asymptomatic patients would appear to not be justified.