Implications of silent strokes

Efficacy of alogliptin combined with motor imagery under hyperbaric oxygen in diabetic nephropathy with silent cerebral infarction

In the present study, we evaluated the curative effect of dipeptidyl peptidase-IV (DPP-IV) inhibitor alogliptin combined with motor imagery under hyperbaric oxygen in diabetic nephropathy (DN) with silent cerebral infarction (SCI). Two-hundred newly diagnosed DN patients with and without SCI were included. The SCI patients were divided into two treatment groups: Alogliptin (A group, n=50) and alogliptin combined with motor imagery under hyperbaric oxygen (B group, n=50). The degrees of neurocognitive dysfunction were evaluated at baseline and after 6 months of treatment. Thromboelastograms (TEGs) mapping were conducted. Serum glycoprotein VI (GPVI) mRNA expression and urine 11-DH-TXB₂ levels were determined. Compared to group A patients, the severity of neurofunctional defects, GPVI mRNA expression and 11-DH-TXB₂ levels were significantly lower in group B (P<0.05), while comprehensive, MoCA scores were higher in group B. The MoCA subscores of visuospatial/executive function, attention and concentration were significantly higher compared to group A (P<0.05). The sub-scores of computation, abstract thinking, language competence, memory and orientation were also higher in group B but the differences were not significant (P>0.05). TEG indexes were improved in both groups after treatment as manifested by increased R and K values, but there was significant improvement in group B. Intra-group comparisons revealed a time-dependent effect of treatment. In conclusion, the treatment of alogliptin combined with motor imagery under hyperbaric oxygen can better promote thrombolysis absorption, restore brain damage and improve neurocognitive function in DN with silent cerebral infarction.

Reliability of Two Ankle-Brachial Index Methods to Predict Silent Lacunar Infarcts: A Population-Based Study in Stroke-Free Older Adults (the Atahualpa Project)

Individuals with an abnormal ankle-brachial index (ABI) are four times more likely to have a silent lacunar infarct (SLI), but reliability of ABI in predicting the presence of these lesions has not been estimated yet. We compared two methods of calculating ABI to assess their reliability in predicting SLIs. Stroke-free Atahualpa residents aged ≥ 60 years underwent MRI of the brain and ABI determinations. Persons with ABI ≥ 1.4 were excluded. Using receiver operator characteristic curve analysis, we calculated the reliability of the traditional as well as an alternative ABI method to identify individuals with SLI. The traditional ABI uses the higher systolic pressure of either the dorsalis pedis or the posterior tibial arteries as the numerator, whereas the alternative ABI uses the lower pressure. Of the 247 participants, 38 (15%) had traditional and 95 (38%) had alternative ABIs ≤ 0.9. Twenty-one individuals had SLI. Traditional and alternative ABIs ≤ 0.9 identified 9 and 13 individuals with SLI, respectively. The traditional ABI had sensitivity of 42.9% (22.6-65.6%) and specificity of 87.2% (81.9-91.1%). The alternative ABI had sensitivity of 61.9% (38.6-81%) and specificity of 63.7% (57-69.9%). The area under the curve for the predictive value of SLI was 0.65 (0.54-0.76) for the traditional and 0.63 (0.52-0.74) for the alternative ABI ≤ 0.9. The ABI is moderately reliable for identifying candidates for MRI screening in studies assessing the burden of SLI in older adults. The traditional ABI seems to be more suitable for this purpose.

Silent Cerebral Embolism during Atrial Fibrillation Ablation:Pathophysiology, Prevention and Management

Although many efforts have been directed to improve atrial fibrillation transcatheter ablation safety, thromboembolism to the brain remains one of the major complications. In fact several studies have confirmed occurrence of silent cerebral embolic lesions by post-procedure magnetic resonance imaging. The present review will focus on the possible mechanisms leading to silent cerebral embolism in an attempt to provide recommendations holding the potential to reduce the incidence of this clinically relevant complication.

Impact of ablation catheter irrigation design on silent cerebral embolism after radiofrequency catheter ablation of atrial fibrillation: results from a pilot study

INTRODUCTION

Silent cerebral lesions (SCL) are a sensitive tool to evaluate thromboembolic risk of catheter ablation. Recent data showed the possibility to reduce thrombus formation when the electrode-tissue interface cooling is optimized by a homogeneous flushing of saline along the entire surface of the distal electrode through a larger number of irrigation holes. The study aim is to compare procedural parameters and safety of pulmonary vein isolation (PVI) performed by using open-irrigated catheters with different irrigation design.

METHODS AND RESULTS

Eighty patients (74% males; age 57 ± 12 years) with paroxysmal AF randomly underwent PVI performed with a new irrigation design catheter (group A, 40 patients) versus a standard irrigated catheter (group B, 40 patients). A cerebral magnetic resonance imaging (MRI) was performed before and after the procedure. Postprocedural brain MRI unveiled SCL in 2 patients in group A and in 3 in group B (5% vs 7.5%, P = 0.500). Intraprocedural ACT was the only independent factor associated with the occurrence of SCL (OR = 0.996; 95% CI 0.994-0.998, P < 0.001). Among procedural parameters, we observed a reduction of irrigation saline volume of 662 mL in group A versus group B (P < 0.001).

CONCLUSION

PVI performed with a new irrigated catheter did not reduce significantly the SCL risk when compared to a standard irrigated catheter. Intraprocedural ACT reduces the SCL risk of 0.4% for each point of ACT increase. For ACT > 320 seconds no SCL occurred. Finally, compared to a standard irrigated catheter, PVI performed with a new irrigation design catheter reduces significantly saline volume infusion.

Analysis of cognitive dysfunction with silent cerebral infarction: a prospective study in Chinese patients

To investigate the relationship between Silent Cerebral Infarction (SCI) and cognitive impairment to testify that Montreal Cognitive Assessment (MoCA) is a more sensitive screening tool than the Mini Mental State Examination (MMSE) to identify cognitive deficits in patients with SCI. We recruited 196 individuals in Shanghai of China and divided them into 2 groups: the SCI group including 112 individuals (45 men and 67 women; aged from 43 to 70 years old) and the control group including 84 individuals (43 men and 41 women; aged from 42 to 79 years old). We collected information including participants' gender, age, blood glucose, kidney function, blood lipids, blood pressure, Electrocardiogram (ECG), carotid artery ultrasound, MMSE score, and MoCA score. SAS software (version 9.1) was used to perform statistical analysis on physical examinations outcomes from 196 participants. Furthermore, multiple logistic regression model was built up to screen out the independent risk factors of SCI. Besides, Receiver Operator Characteristic (ROC) analysis was also used. Multivariate logistic regression analysis showed that abnormal ECG and existence of carotid artery plaques were independent risk factors of SCI occurrence, while MoCA scores was negatively associated with SCI risk. Moreover, MoCA might be more valuable in predicting vascular cognitive impairment (VCI) than MMSE (0.667 vs 0.626). We found that the MMSE was generally insensitive to detect cognitive impairment; but the MoCA has a good balance of sensitivity and specificity at the cut-score of 26. We found that the patients with SCI might accompany with VCI and the MoCA appeared to be an excellent screening test for patients with SCI, worthy of being promoted in the clinical practitioning on Chinese population.