Echocardiographic evidence of innate aortopathy in the human intracranial aneurysm

Prevalence of Intracranial Aneurysm in Patients With Aortic Disease in Korea: A Nationwide Population-Based Study

Background Patients with aortic disease (AD) might have a higher prevalence of intracranial aneurysm (IA). The present study evaluated the prevalence of IA in patients with AD and identified potential risk factors of IA using nationwide representative cohort sample data. Methods and Results We defined AD as both aortic dissections and aortic aneurysms. This study used a nationwide representative cohort sample from the Korea National Health Insurance Service-National Sample Cohort database from 1.1million patients. Using χ² or Fisher's exact tests, the prevalence of the IA in patients with AD and potential risk factors for their concurrence were analyzed. The prevalence of IA in patients with AD was 6.8% (155/2285). The adjusted odds ratios (OR) for having concurrent IA in patients with AD was 3.809 (95% CI, 3.191-4.546; P<0.01). Patients with AD and hypertension were >19 times more likely to be affected by IA (adjusted OR, 18.679; 95% CI, 16.555-21.076; P<0.01). Patients with AD and diabetes mellitus, old age (>60 years), and male sex were >4, 3, and 2 times more likely to be affected by IA, respectively (adjusted OR, 4.291, 3.469, and 1.983, respectively; 95% CI, 3.914-4.704, 3.152-3.878, and 1.779-2.112, respectively). Subgroup analysis with socioeconomic status or disability revealed that the prevalence of IA was significantly higher in all groups. Conclusions In the current population-based study, the prevalence of IA in patients with AD was quadrupled compared with that in the general population. Early IA screening might be considered among patients with AD for appropriate management.

New Pathophysiological Considerations on Cerebral Aneurysms

Cerebral aneurysm is a common cerebrovascular disease that is sometimes complicated by rupture or an enlarged mass. We are now aggressively evaluating and managing unruptured cerebral aneurysms based on a significant concern for the high morbidity and mortality related to its associated complications. However, the actual rupture rate is very low and the diagnostic and treatment modalities are expensive and invasive, which may lead to unnecessary costs and potential medical complications. This disproportionate situation is related to a poor understanding of the natural course and pathophysiology of cerebral aneurysms. In consideration of the concept that not all cerebral aneurysms must be removed, we need to examine their course and progression more accurately. Cerebral aneurysms may follow a variety of pathophysiological scenarios over their lifetime, from formation to growth and rupture. The disease course and the final outcome can differ depending on the timing and intensity of the pathological signals acting on the cerebral vessel wall. We should delineate a method of predicting the stability and risk of rupture of the lesion based on a comprehensive knowledge of the vessel wall integrity. This review deals with the basic knowledge and advanced concepts underlying the pathophysiology of cerebral aneurysms.

Dilating Vascular Diseases: Pathophysiology and Clinical Aspects

Atherosclerotic disease of the vessels is a significant problem affecting mortality and morbidity all over the world. However, dilatation of the vessels either in the arterial system or in the venous territory is another vessel disease. Varicocele, pelvic, and peripheral varicose veins and hemorrhoids are aneurysms of the venous vascular regions and have been defined as dilating venous disease, recently. Coronary artery ectasia, intracranial aneurysm, and abdominal aortic aneurysm are examples of arterial dilating vascular diseases. Mostly, they have been defined as variants of atherosclerosis. Although there are some similarities in terms of pathogenesis, they are distinct from atherosclerotic disease of the vessels. In addition, pathophysiological and histological similarities and clinical coexistence of these diseases have been demonstrated both in the arterial and in the venous system. This situation underlies the thought that dilatation of the vessels in any vascular territory should be considered as a systemic vessel wall disease rather than being a local disease of any vessel. These patients should be evaluated for other dilating vascular diseases in a systematic manner.

Prevalence of Intracranial Aneurysms in Patients with Aortic Aneurysms

BACKGROUND AND PURPOSE

Previous studies have suggested an association between aortic aneurysms and intracranial aneurysms with a higher prevalence of intracranial aneurysms in patients with aortic aneurysms. The aims of the present study were to evaluate the incidence of intracranial aneurysms in a large cohort of patients with aortic aneurysms and to identify potential risk factors for intracranial aneurysms in this population.

MATERIALS AND METHODS

We included all patients with aortic aneurysms (either abdominal and/or thoracic) who had available cerebral arterial imaging and were seen at our institution during a 15-year period. We identified patients with intracranial aneurysms. Patient demographics, comorbidities, and aortic aneurysm and intracranial aneurysm sizes and locations were analyzed. Univariate analysis was performed with a χ(2) test for categoric variables and a Student t test or ANOVA for continuous variables.

RESULTS

A total of 1081 patients with aortic aneurysms were included. Of them, 440 (40.7%) had abdominal aortic aneurysms, 446 (41.3%) had thoracic aortic aneurysms, and 195 (18.0%) had both abdominal aortic and thoracic aortic aneurysms. The overall prevalence of associated intracranial aneurysms in patients with aortic aneurysms was 11.8% (128/1081), with 12.7% (56/440), 10.8% (48/446), and 12.3% (24/195), respectively, in patients with abdominal aortic aneurysms, thoracic aortic aneurysms, and both thoracic aortic aneurysms and abdominal aortic aneurysms. Female patients had a higher risk of associated intracranial aneurysms (OR = 2.08; 95% CI, 1.49-3.03; P = .0002). There was a slight association between abdominal aortic aneurysm size and the prevalence of intracranial aneurysms (OR = 1.02; 95% CI, 1.01-1.03; P = .045). There was no significant association between the locations of the aortic and intracranial aneurysms (P = .93).

CONCLUSIONS

The prevalence of intracranial aneurysms is high in patients with aortic aneurysms. Further studies examining the role and cost-effectiveness of intracranial aneurysm screening in patients are warranted.

Site-Specific Relationship Between Intracranial Aneurysm and Aortic Aneurysm

BACKGROUND AND PURPOSE

The high prevalence of intracranial aneurysms (IAs) in patients with a bicuspid aortic valve or coarctation of the aorta suggests a link between IA and aortic pathology. However, studies reporting this link do not sufficiently address the heterogeneity of IAs arising from different anatomic locations. This study aimed to explore whether a location-specific relationship exists between the 2 kinds of aneurysms.

METHODS

Retrospective institutional analysis of patients aged ≥18 years with both IA and an aortic aneurysm (AA) was performed from 2005 to 2014. IAs were categorized based on their locations: internal carotid artery, other anterior circulation, and posterior arteries. AAs were classified as ascending, descending, infrarenal, or multiple. We analyzed the clinical characteristics and the distribution of IA in each AA group.

RESULTS

Of 2375 patients, 660 with available intracranial angiography were screened for IA. We identified 71 patients with 97 IAs. The frequency of both anterior circulation-IAs and internal carotid artery-IAs differed significantly among the AA groups (P=0.001 and P=0.01, respectively). Anterior circulation-IAs were most frequently observed in ascending AA group and least frequently in infrarenal AA group. In contrast, internal carotid artery-IAs were found mostly in infrarenal AA group, least in ascending AA group. Proportions of patients having anterior circulation-IA and internal carotid artery-IA were also highest in ascending AA group and infrarenal AA group, respectively. The number of posterior arteries-IAs was too small to characterize.

CONCLUSIONS

The differing distribution patterns of IA among AA groups suggest a site-specific sharing of pathomechanism between the 2 types of aneurysms.