Validation of external and internal exposome of the findings associated to cerebral small vessel disease: A Mendelian randomization study

The exposome characterizes all environmental exposures and their impact on a disease. To determine the causally-associated components of the exposome for cerebral small vessel disease (CSVD), we performed mendelian randomization analysis of 5365 exposures on six clinical and subclinical CSVD measures. We found statistically significant evidence (FDR-corrected P < 0.05) that hypertension, high cholesterol, longer television-watching time, lower educational qualifications, younger age of first sexual intercourse, smoking, reduced pulmonary function, higher subjective overall health rating, and frequent tiredness were associated with increased risk of intracerebral hemorrhage or small vessel stroke. Adiposity, diabetes, frequent alcoholic drinks, higher white blood cell count and neutrophil count were significantly associated with higher risk of non-lobar hemorrhage or small vessel stroke, but not lobar hemorrhage. Hypertension, higher arm or leg fat-free mass and higher sitting height were significantly associated with higher white matter hyperintensities. The results were robust to sensitivity analyses and showed no evidence of horizontal pleiotropy. We also identified 41 exposures suggestively associated (uncorrected P < 0.05) with multiple CSVD measures as the “the CSVD exposome”. This exposome-wide association study provides insight into CSVD development and prevention.

Comparison of transcranial doppler ultrasound indices in large and small vessel disease cerebral infarction

Background: Atherosclerotic involvement of large and small cerebral arteries leading to infarction is among the most prevalent subtypes of stroke worldwide. The hemodynamic changes due to these arterial pathologies can be studied non-invasively and in real-time by using transcranial Doppler (TCD) techniques. TCD indices of the studied arteries may guide the clinician in differentiating these two underlying arterial pathologies. Methods: A cross-sectional study of patients with small and large vessel types of cerebral infraction based on the Trial of ORG 10172 in Acute Stroke Treatment (TOAST) stroke classification was undertaken in the inpatient population of neurology service of Razi Hospital, Tabriz, Iran, from October 2018 to October 2019. After clinical diagnosis, all cases underwent TCD studies, brain magnetic resonance imaging (MRI), and brain and cervical four-vessel magnetic resonance angiography (MRA). The results of TCD indices related to major arteries of the circle of Willis were tabulated and compared between large and small vessel subtypes of cerebral infarction. Results: A statistically significant difference between right middle cerebral artery (MCA) pulsatility index (PI), left MCA PI, right internal carotid artery (ICA) PI, end-diastolic velocity (EDV), left ICA PI, left ICA EDV, left anterior cerebral artery (ACA) PI, and right vertebral artery (VA) PI measures of the two groups was seen (P < 0.05). In comparison to the large vessel group, left ACA, right VA, and bilateral MCAs and ICAs in the small-vessel stroke group demonstrated an elevated PI. Conclusion: A significant increase of PI occurs in the majority of intracranial arteries of patients with small vessel stroke. This makes PI a valuable marker for differentiating strokes with different underlying pathophysiologies.

Safety and Efficacy of Drug-Coated Balloons Versus Drug-Eluting Stents in Acute Coronary Syndromes: A Prespecified Analysis of BASKET-SMALL 2

Background: Drug-coated balloons (DCBs) are an established treatment strategy for coronary artery disease. Randomized data on the application of DCBs in patients with an acute coronary syndrome (ACS) are limited. We evaluated the impact of clinical presentation (ACS versus chronic coronary syndrome) on clinical outcomes in patients undergoing DCB or drug-eluting stent (DES) treatment in a prespecified analysis of the BASKET-SMALL 2 trial (Basel Kosten Effektivitäts Trial–Drug-Coated Balloons Versus Drug-Eluting Stents in Small Vessel Interventions). Methods: BASKET-SMALL 2 randomized 758 patients with small vessel coronary artery disease to DCB or DES treatment and followed them for 3 years regarding major adverse cardiac events (cardiac death, nonfatal myocardial infarction, and target vessel revascularization). Results: Among 758 patients, 214 patients (28.2%) presented with an ACS (15 patients [7%], ST-segment–elevation myocardial infarction; 109 patients [50.9%], non–ST-segment–elevation myocardial infarction; 90 patients [42.1%], unstable angina pectoris). At 1-year follow-up, there was no significant difference in the incidence of the primary end point by randomized treatment in patients with ACS (hazard ratio, 0.50 [95% CI, 0.19–1.26] for DCB versus DES) or chronic coronary syndrome (hazard ratio, 1.29 [95% CI, 0.67–2.47] for DCB versus DES). There was no significant interaction between clinical presentation and treatment effect ( P for interaction, 0.088). For cardiac death ( P for interaction, 0.049) and nonfatal myocardial infarction ( P for interaction, 0.010), a significant interaction between clinical presentation and treatment was seen at 1 year with lower rates of these secondary end points in patients with ACS treated by DCB. At 3 years, there were similar major adverse cardiac event rates throughout groups without significant interaction between clinical presentation and treatment ( P for interaction, 0.301). All-cause mortality was higher in ACS compared with chronic coronary syndrome; however, there was no difference between DCB and DES irrespective of clinical presentation. Conclusions: In this subgroup analysis of the BASKET-SMALL 2 trial, there was no interaction between indication for percutaneous coronary intervention (acute versus chronic coronary syndrome) and treatment effect of DCB versus DES in patients with small vessel coronary artery disease. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01574534.

Neuropathology of Vascular Brain Health: Insights From Ex Vivo Magnetic Resonance Imaging–Histopathology Studies in Cerebral Small Vessel Disease

Sporadic cerebral small vessel disease (SVD) is a major contributor to vascular cognitive impairment and dementia in the aging human brain. On neuropathology, sporadic SVD is characterized by abnormalities to the small vessels of the brain predominantly in the form of cerebral amyloid angiopathy and arteriolosclerosis. These pathologies frequently coexist with Alzheimer disease changes, such as plaques and tangles, in a single brain. Conversely, during life, magnetic resonance imaging (MRI) only captures the larger manifestations of SVD in the form of parenchymal brain abnormalities. There appears to be a major knowledge gap regarding the underlying neuropathology of individual MRI-detectable SVD abnormalities. Ex vivo MRI in postmortem human brain tissue is a powerful tool to bridge this gap. This review summarizes current insights into the histopathologic correlations of MRI manifestations of SVD, their underlying cause, presumed pathophysiology, and associated secondary tissue injury. Moreover, we discuss the advantages and limitations of ex vivo MRI-guided histopathologic investigations and make recommendations for future studies.

Indirect Flow Diversion for Off-Centered Bifurcation Aneurysms and Distant Small-Vessel Aneurysms, a Retrospective Proof of Concept Study From Five Neurovascular Centers

Background: Treatment of cerebral aneurysms using hemodynamic implants such as endosaccular flow disruptors and endoluminal flow diverters has gained significant momentum during recent years. The intended target zone of those devices is the immediate interface between aneurysm and parent vessel. The therapeutic success is based on the reduction of aneurysmal perfusion and the subsequent formation of a neointima along the surface of the implant. However, a subset of aneurysms–off-centered bifurcation aneurysms involving the origin of efferent branches and aneurysms arising from peripheral segments of small cerebral vessels–oftentimes cannot be treated via coiling or implanting a hemodynamic implant at the neck level for technical reasons. In those cases, indirect flow diversion–a flow diverter deployed in the main artery proximal to the parent vessel of the aneurysm–can be a viable treatment strategy, but clinical evidence is lacking in this regard.Materials and Methods: Five neurovascular centers contributed to this retrospective analysis of patients who were treated with indirect flow diversion. Clinical data, aneurysm characteristics, anti-platelet medication, and follow-up results, including procedural and post-procedural complications, were recorded.Results: Seventeen patients (mean age: 60.5 years, range: 35–77 years) with 17 target aneurysms (vertebrobasilar: n = 9) were treated with indirect flow diversion. The average distance between the flow-diverting stent and the aneurysm was 1.65 mm (range: 0.4–2.4 mm). In 15/17 patients (88.2%), perfusion of the aneurysm was reduced immediately after implantation. Follow-ups were available for 12 cases. Delayed opacification (OKM A3: 11.8%), reduction in size (OKM B1-3: 29.4%) and occlusion (D1: 47.1%) were observable at the latest investigation. Clinically relevant procedural complications and adverse events in the early phase and in the late subacute phase were not observed in any case.Conclusion: Our preliminary data suggest that indirect flow diversion is a safe, feasible, and effective approach to off-centered bifurcation aneurysms and distant small-vessel aneurysms. However, validation with larger studies, including long-term outcomes and optimized imaging, is warranted.