Characteristics of Intracranial Aneurysms According to Levels of Coronary Artery Calcium

Low and Borderline Ankle-Brachial Index Is Associated With Intracranial Aneurysms: A Retrospective Cohort Study

BACKGROUND AND OBJECTIVES

A low ankle-brachial index (ABI) has been linked to systemic inflammation and an elevated risk of cardiovascular events, most notably myocardial infarction and stroke. Intracranial aneurysms (IAs) share similar risk factors with other cardiovascular diseases. However, the association between low ABI and IAs has not been sufficiently investigated. Our objective was to investigate the potential connection between ABI values and the prevalence of unruptured IAs.

METHODS

This retrospective cohort study reviewed 2751 patients who had ABI measurements at a public tertiary hospital from January 2011 to December 2013. Patients with available cerebrovascular imaging or a diagnosis of ruptured IA were included in the study (n = 776) to examine the association between ABI and saccular IAs. The patients were classified into 4 groups: low ABI (≤0.9, n = 464), borderline ABI (0.91-0.99; n = 47), high ABI (>1.4, n = 57), and normal ABI (1.00-1.40; n = 208).

RESULTS

The prevalence of IAs was 20.3% (18.1% unruptured IAs) in the low ABI group, 14.9% (12.8% unruptured IAs) in the borderline ABI group, 7.0% (5.3% unruptured IAs) in the high ABI group, and 2.4% (1.9% unruptured IAs) in the normal ABI group (P < .001). There were no significant differences in the prevalence of ruptured IAs between the ABI groups (P = .277). Sex- and age-adjusted multinomial regression, including clinically relevant variables, revealed that low ABI (odds ratio [OR], 13.02; 95% CI, 4.01-42.24), borderline ABI (OR, 8.68; 95% CI, 2.05-36.69), and smoking history (OR, 2.01; 95% CI, 1.07-3.77) were associated with unruptured IAs.

CONCLUSION

The prevalence of unruptured IAs was 9-fold higher in the low ABI group and nearly 7-fold higher in the borderline ABI group when compared with the normal ABI group. ABI measurements could be clinically relevant for identifying individuals at higher risk of IAs and may help guide screening and preventive strategies.

Is coronary artery calcium an independent risk factor for white matter hyperintensity?

BACKGROUND

Cardiovascular diseases have been considered the primary cause of disability and death worldwide. Coronary artery calcium (CAC) is an important indicator of the severity of coronary atherosclerosis. This study is aimed to investigate the relationship between CAC and white matter hyperintensity (WMH) in the context of diagnostic utility.

METHODS

A retrospective analysis was conducted on 342 patients with a diagnosis of WMH on magnetic resonance images (MRI) who also underwent chest computed tomography (CT) scans. WMH volumes were automatically measured using a lesion prediction algorithm. Subjects were divided into four groups based on the CAC score obtained from chest CT scans. A multilevel mixed-effects linear regression model considering conventional vascular risk factors assessed the association between total WMH volume and CAC score.

RESULTS

Overall, participants with coronary artery calcium (CAC score > 0) had larger WMH volumes than those without calcium (CAC score = 0), and WMH volumes were statistically different between the four CAC score groups, with increasing CAC scores, the volume of WMH significantly increased. In the linear regression model 1 of the high CAC score group, for every 1% increase in CAC score, the WMH volume increases by 2.96%. After including other covariates in model 2 and model 3, the β coefficient in the high CAC group remains higher than in the low and medium CAC score groups.

CONCLUSION

In elderly adults, the presence and severity of CAC is related to an increase in WMH volume. Our findings suggest an association between two different vascular bed diseases in addition to traditional vascular risk factors, possibly indicating a comorbid mechanism.

Abdominal Aortic Calcification Volume Is Associated with Wall Enhancement of Unruptured Intracranial Aneurysm

OBJECTIVE

Inflammatory atherosclerotic remodeling of unruptured intracranial aneurysms (UIAs) wall, which could be detected as aneurysm wall enhancement (AWE) in MR vessel wall imaging (VWI), plays a pivotal role in pathophysiology of progression to rupture. On the other hand, abdominal aortic calcification reflects the extent of systemic atherosclerosis, which in turn predicts the risk of atherosclerotic cardiovascular as well as cerebrovascular diseases. This study sought to investigate whether the abdominal aortic calcification was associated with increased wall enhancement of UIAs in VWI.

METHODS

This retrospective study reviewed subjects who underwent evaluation using 3T MR-VWI of UIAs and abdominal CT before endovascular treatments for UIAs between 2018 to 2020. Abdominal aortic calcification volume (ACV) was quantitatively measured from abdominal CT scans between renal arteries and bifurcation. The presence of AWE was correlated with patient profile, aneurysm morphology, and the ACV.

RESULTS

A total of 42 patients with 50 UIAs were included. AWE was detected in 19 (38.0%) UIAs. Maximum diameter (9.2 ± 5.0 mm vs 5.3 ± 1.5 mm, P < 0.01) and the ACV (8.2 ± 6.0 mL vs 4.7 ± 4.6 mL, P = 0.038) were significantly higher in UIAs with AWE than those without AWE.

CONCLUSIONS

The ACV was significantly associated with increased wall enhancement of UIAs. Systemic atherosclerosis might be a risk factor for the instability of UIAs. Future studies examining the effect of medications for systemic atherosclerosis on the extent of AWE in UIAs is warranted.

Association of Donor Brain Death Due to Stroke With Prognosis After Heart Transplantation

BACKGROUND

The proximate cause of donor brain death is not considered a conventional risk factor in modern heart transplantation.

OBJECTIVES

This study aimed to investigate the effect of the cause of donor brain death on recipients.

METHODS

Using the United Network for Organ Sharing registry, long-term mortality and allograft failure were compared in recipients who underwent heart transplantation in the United States from 2005 through 2018 between allograft recipients from donors with stroke as the cause of brain death (n = 3,761) vs nonstroke causes (n = 14,677). Inverse probability weighting was used for risk adjustment. Interactions were investigated between the cause of brain death and other conventional donor risk factors for recipient mortality.

RESULTS

There was an interaction between the cause of brain death and donor age (P_interaction = 0.008). When allografts were procured from donors aged 40 years or younger, stroke as the cause of brain death was associated with an increased risk of mortality (23% vs 19% at 5 years; HR: 1.17; 95% CI: 1.02-1.35) and allograft failure (HR: 1.30; 95% CI: 1.04-1.63). When donors were older than 40 years, the cause of brain death was not associated with outcomes.

CONCLUSIONS

As the cause of donor brain death, stroke had a substantially different effect on recipient and allograft survival depending on donor age. In the case of younger donor ages, stroke was associated with higher recipient mortality and allograft failure than other causes of brain death. The strength of this association decreased with increasing donor age such that the increased hazard was no longer present in donors older than approximately 40 years.

Increased Concentrations of Atherogenic Proteins in Aneurysm Sac Are Associated with Wall Enhancement of Unruptured Intracranial Aneurysm

Current MR-vessel wall imaging (VWI) of unruptured intracranial aneurysms (UIAs) permits the visualization of wall structures. Aneurysm wall enhancement (AWE) was associated with atherosclerotic remodeling of the aneurysm wall accompanied by infiltration of inflammatory cells, potentially contributing to rupture. This study sought to investigate whether the luminal concentrations of atherosclerotic proteins in the aneurysm sac were associated with increased wall enhancement of UIAs in VWI. Subjects undergoing endovascular treatment for UIAs were prospectively recruited. All subjects underwent evaluation using 3 T-MRI including pre/post contrast VWI of the UIAs. Blood samples were collected from the aneurysm sac and the parent artery during endovascular procedures. The presence of AWE was correlated with the delta difference in concentration between the aneurysm sac and the parent artery for each atherosclerotic protein. A total of consecutive 45 patients with 50 UIAs were enrolled. The delta differences of anti-oxidized low-density lipoprotein (LDL) antibody, small dense LDL, and lipoprotein(a) [Lp(a)] were significantly higher in UIAs with AWE compared with those without AWE (767.6 ± 1957.1 versus - 442.4 ± 1676.3 mIU/mL, p = 0.02, 114.8 ± 397.7 versus - 518.5 ± 1344.4 μg/mL, p = 0.04, and - 5.6 ± 11.3 versus - 28.7 ± 38.5 μg/mL, p = 0.01, respectively). In multivariate logistic regression analysis, the delta Lp(a) was significantly associated with AWE (p = 0.04). Increased concentrations of atherogenic proteins in the aneurysm sac were significantly associated with wall enhancement of UIAs. Future studies examining the effect of medications for atherosclerosis on the atherogenic proteins within the aneurysm sac and hence the wall enhancement are warranted.

Intracranial aneurysm is predicted by abdominal aortic calcification index: A retrospective case-control study

BACKGROUND AND AIMS

Patients with intracranial aneurysms (IA) have excess mortality for cardiovascular diseases, but little is known on whether atherosclerotic manifestations and IA coexist. We investigated abdominal aortic calcification index (ACI) association with unruptured and ruptured IAs.

METHODS

This retrospective case-control study reviews all tertiary centers patients (n = 24,660) who had undergone head computed tomography angiography (CTA), magnetic resonance angiography (MRA) or digital subtraction angiography (DSA) for any reason between January 2003 and May 2018. Patients (n = 2020) with unruptured or ruptured IAs were identified, and patients with available abdominal CT were included. IA patients were matched by sex and age to controls (available abdomen CT, no IAs) in ratio of 1:3. ACI was measured from abdomen CT scans and patient records were reviewed.

RESULTS

1720 patients (216 ruptured IA (rIA), 246 unruptured IA (UIA) and 1258 control) were included. Mean age was 62.9 ± 11.9 years and 58.2% were female. ACI (OR 1.02 per increment, 95%CI 1.01-1.03) and ACI>3 (OR 5.77, 95%CI 3.29-10.11) increased risk for rIA compared to matched controls. UIA patients' ACI was significantly higher but ACI did not increase odds for UIA compared to matched controls. History of coronary artery disease was less frequent in rIA patients. There was no calcification in aorta in 8.8% rIA and 13.6% UIA patients (matched controls 25.7% and 22.6% respectively, p < 0.01).

CONCLUSIONS

Aortic calcification is greater in rIA and UIA patients than matched controls. ACI increases risk for rIAs.

Intracranial aneurysms in patients receiving kidney transplantation for autosomal dominant polycystic kidney disease

BACKGROUND

Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited kidney disease, leading to kidney failure. One of the most serious extrarenal complications of ADPKD is comorbid intracranial aneurysms. The aim of this study is to evaluate the prevalence, rupture rate, and treatment outcomes of intracranial aneurysms in ADPKD.

METHODS

Adult patients with a documented diagnosis of ADPKD who received kidney transplantation at our center from January 1994 to December 2018 were included in the study. Medical history, physical examination, laboratory findings, imaging studies, and operation records were collected and analyzed from our database.

RESULTS

Among 154 kidney transplant recipients with ADPKD, 113 (73.4%) patients were screened for intracranial aneurysms preoperatively. Twenty three patients (14.9%) had intracranial aneurysms with mean diameter size of 4.5 ± 2.7 mm. Nine patients (5.8%) experienced aneurysm rupture and the mean age at time of rupture was 34.9 ± 9.3 years. Twelve patients (52.2%) presented with multiple aneurysms. The most common aneurysm location was the bifurcation of the middle cerebral artery (34.9%). Clipping was the most common treatment in both ruptured and unruptured aneurysms.

CONCLUSIONS

Intracranial aneurysms are more frequent in patients with ADPKD, and the average age of intracranial artery rupture in patients with ADPKD is earlier than in the general population. It is necessary to consider proper evaluation and management of intracranial aneurysms when counseling ADPKD patients who will undergo kidney transplantation.