Abstract
Prior studies suggest high prevalence of intracranial aneurysms (IA) in patients with infrarenal abdominal aortic aneurysms (AAA). We reviewed our multicenter experience in clinical detection/treatment of IAs in AAA patients and estimated the risk of IA in patients with AAA relative to patients without AAA. We reviewed cases of vascular surgery infrarenal AAA repairs at three Mayo Clinic sites from January 1998 to December 2018. Concurrent controls were randomly matched in a 1:1 ratio by age, sex, smoking history, and head imaging characteristics. Conditional logistic regression was used to calculate odds ratios. We reviewed 2,300 infrarenal AAA repairs. Mean size of AAA at repair was 56.9 ± 11.4 mm; mean age at repair, 75.8 ± 8.0 years. 87.5% of the cases ( n = 2014) were men. Head imaging was available in 421 patients. Thirty-seven patients were found to have 45 IAs for a prevalence of 8.8%. Mean size of IA was 4.6 ± 3.5 mm; mean age at IA detection, 72.0 ± 10.8 years. Thirty (81%) out of 37 patients were men. Six patients underwent treatment for IA: four for ruptured IAs and two for unruptured IAs. All were diagnosed before AAA repair. Treatment included five clippings and one coil-assisted stenting. Time from IA diagnosis to AAA repair was 16.4 ± 11.0 years. Two of these patients presented with ruptured AAA, one with successful repair and a second one that resulted in death. Odds of IA were higher for patients with AAA versus those without AAA (8.8% [37/421] vs. 3.1% [13/421]; OR 3.18; 95% confidence interval, 1.62–6.27, p < 0.001). Co-prevalence of IA among patients with AAA was 8.8% and is more than three times the rate seen in patients without AAA. All IAs were diagnosed prior to AAA repair. Surveillance for AAA after IA treatment could have prevented two AAA ruptures and one death.
Keywords: abdominal aortic aneurysm, stroke, aneurysm, endovascular repair, ultrasound
The prevalence of unruptured intracranial aneurysms (IAs) in the general population is estimated to be 3.2%. 1 The prevalence of infrarenal abdominal aortic aneurysms (AAA) is estimated to be 1 to 2% in the general population, with up to 10% prevalence in individuals older than 70 years of age. 2 Aneurysmal subarachnoid hemorrhage is the second leading cause of short-term stroke-related mortality (26–36%). 3 4 Rupture of an AAA carries a similarly high 30-day mortality rate of 36 to 58%. 5 6 Furthermore, genome-wide association studies have identified susceptibility loci for both IA and AAA, suggesting a shared molecular pathophysiology. 7 8 9 Estimates of the co-prevalence of IA and AAA vary widely from 2.2 to 20.3%. 10 11 12 13 14 Effective surgical and endovascular treatments exist for unruptured intracranial and AAAs; therefore, screening high-risk individuals could significantly reduce mortality related to both types of aneurysmal rupture. In a previous prospective study, 15 we observed a 12% prevalence of previously undiagnosed AAA in patients who presented with aneurysmal subarachnoid hemorrhage. The primary aim was to review a two-decade multicenter experience in the clinical detection and treatment of IAs in patients with AAA and to determine the degree to which having an AAA increases the rate of IA.
Methods
We reviewed a consecutive series of patients from our three vascular surgery centers at the three Mayo Clinic sites (Florida, Arizona, and Minnesota), that underwent infrarenal AAA repair between January 1998 and December 2018. Data collection included details of each patient's clinical presentation, comorbidities, surgical management, and follow-up through a retrospective chart review. This study was approved by the Mayo Clinic Institutional Review Board (IRB#18–010959). Informed consent was not obtained for the study, since it was deemed minimal risk to patients. The cases in this analysis were the subset of individuals from the consecutive series described above who underwent head imaging, allowing for the detection of an unruptured IA or an aneurysmal subarachnoid hemorrhage. Cases were randomly matched in a 1:1 ratio to non-AAA controls. Associations of AAA with IA were examined using a conditional logistic regression model, where the odds ratio for having an IA detected on head imaging and the corresponding 95% confidence interval (CI) were estimated. The process of random matching was facilitated by using two software programs available at our institution including Illuminate (Illuminate Software, Waco, TX) and i2b2 (i2b2 tranSMART Foundation, Wakefield, MA) and the criteria included: age, sex, type of head imaging, year of head imaging, location at which head imaging was obtained, and smoking history. The criterion for age matching was broadened to include ± 3 years due to inability to find exact matches for age to the patients in our study group.
Data are reported as means and standard deviations for continuous variables or as frequencies for categorical variables. Differences between categorical variables were tested using χ 2 test and differences between continuous variables were tested using Student t -test when deemed appropriate. Long-term outcomes were performed descriptively due to the small absolute number of patients with IAs among cases. Statistical analyses were performed using SAS (version 9.4; SAS Institute Inc., Cary, NC).
Results
There were 2,300 infrarenal AAA repairs during our study period. A total of 2,014 (87.5%) were men. Mean age at AAA repair was 75.8 ± 8.0 years and mean aneurysm size at repair was 56.9 ± 11.4 mm. Concurrent cross-sectional head imaging was available in 421 patients, and they included magnetic resonance angiography (MRA) in 216, magnetic resonance imaging with contrast in 132, computed tomography angiography (CTA) in 63, and computed tomography (CT) with contrast in 10 patients. Patient demographics including comorbidities, medications, body mass index, preoperative hemoglobin, and serum creatinine are included in Table 1 . There were 37 patients with 45 IAs (32 with one IA; three with two IAs; one with three IAs and one with four IAs) for a prevalence of 8.8% with one or more aneurysms. Patients with AAA + IA have significantly higher percentage of coronary artery disease (67.6 vs. 45.8%, p = 0.011), history of coronary artery bypass graft (40.5 vs. 20.3%, p = 0.005), and congestive heart failure (24.3 vs. 4.4%, p < 0.00001) compared with patients with AAA only. The three most common reasons for obtaining cross-sectional head imaging included suspicion for transient ischemic attack/stroke/subarachnoid hemorrhage ( n = 163), known intracranial or carotid artery stenosis ( n = 99), and intracranial neoplasm ( n = 43). Other reasons for imaging are shown in Table 2 .
Table 1. Demographics for patients with abdominal aortic aneurysm repair without intracranial aneurysms ( n = 384) and with intracranial aneurysms ( n = 37) .
| All patients with abdominal aortic aneurysm ( n = 421) |
Patients with abdominal aortic aneurysm without intracranial aneurysms ( n = 384) | Patients with abdominal aortic aneurysm with intracranial aneurysm ( n = 37) | p | |
|---|---|---|---|---|
| Mean ± Standard deviation | Mean ± Standard deviation | Mean ± Standard deviation | ||
| Age at time of repair (y) | 76 ± 7.8 | 76 ± 7.7 | 74 ± 8.6 | 0.10 a |
| Body mass index (kg/m 2 ) | 27.4 ± 5.1 | 27.5 ± 5.2 | 26.8 ± 4.2 | 0.48 a |
| Preoperative hemoglobin (mg/dL) | 13.1 ± 1.8 | 13.1 ± 1.8 | 13.0 ± 2.6 | 0.65 a |
| Preoperative serum creatinine (mg/dL) | 1.2 ± 0.7 | 1.2 ± 0.7 | 1.1 ± 0.3 | 0.24 a |
| Size of abdominal aortic aneurysm (mm) | 56.3 ± 11.3 | 56.4 ± 11.2 | 55.5 ± 11.8 | 0.65 a |
| Male sex | 371 (88.1%) | 341 (88.8%) | 30 (81.1%) | 0.17 b |
| Comorbidities | ||||
| Hypertension | 345 (81.9%) | 312 (81.3%) | 33 (89.2%) | 0.36 c |
| Coronary artery disease | 201 (47.7%) | 176 (45.8%) | 25 (67.6%) | 0.015 b |
| Prior coronary artery bypass graft | 93 (22.1%) | 78 (20.3%) | 15 (40.5%) | 0.006 b |
| Prior percutaneous coronary intervention | 58 (13.8%) | 53 (13.8%) | 5 (13.5%) | 0.93 b |
| Chronic obstructive pulmonary disease | 68 (16.2%) | 61 (15.9%) | 7 (18.9%) | 0.66 b |
| Diabetes mellitus | 47 (11.2%) | 42 (10.9%) | 5 (13.5%) | 0.66 b |
| Congestive heart failure | 26 (6.2%) | 17 (4.4%) | 9 (24.3%) | <0.001 b |
| Hemodialysis | 5 (1.2%) | 4 (1.0%) | 1 (2.7%) | 0.37 c |
| Statins | 306 (72.7%) | 277 (72.1%) | 29 (78.4%) | 0.52 b |
| Aspirin | 296 (70.3%) | 267 (69.5%) | 29 (78.4%) | 0.34 b |
| Beta blockers | 254 (60.3%) | 228 (59.4%) | 26 (70.3%) | 0.24 b |
| Angiotensin converting enzyme inhibitors | 147 (34.9%) | 137 (35.7%) | 10 (27.0%) | 0.26 b |
| Warfarin | 41 (9.7%) | 36 (9.4%) | 5 (13.5%) | 0.44 b |
| Clopidogrel | 37 (8.8%) | 33 (8.6%) | 4 (10.8%) | 0.76 c |
| Novel oral anticoagulant | 2 (0.5%) | 2 (0.5%) | 0 (0.0%) | 1.0 c |
Abbreviations: AAA, abdominal aortic aneurysm; IA, intracranial aneurysms.
Note: Categorical characteristics are presented as percentage (number of patients with characteristic/number of patients with data available); Continuous characteristics are presented as mean ± standard deviation (number of patients with data available).
Two-sample t -test.
Chi-square test.
Fisher's exact test.
Table 2. Reasons for cross-sectional head imaging or noninvasive intracranial arterial imaging of patients with AAA and non-AAA controls.
| Reasons | AAA patients with head imaging ( n = 421) |
Matched patients non-AAA with head imaging ( n = 421) |
|---|---|---|
| Transient Ischemic Attack/Stroke/Subarachnoid hemorrhage | 163 (38.7%) | 160 (38.0%) |
| Carotid/intracranial artery stenosis | 99 (23.5%) | 67 (15.9%) |
| Intracranial neoplasm | 43 (10.2%) | 34 (8.1%) |
| Headache/Dizziness | 30 (7.1%) | 30 (7.1%) |
| Distant neoplasm | 25 (5.9%) | 31 (7.4%) |
| Neuralgia/Seizures/Altered mental status | 20 (4.8%) | 33 (7.8%) |
| Personal/family history of intracranial aneurysm | 11 (2.6%) | 13 (3.1%) |
| Multiple sclerosis/Parkinson's disease | 10 (2.4%) | 30 (7.1%) |
| Trauma/Horner's syndrome/AVM | 7 (1.7%) | 11 (2.6%) |
Abbreviations: AAA, abdominal aortic aneurysms; AVM, arteriovenous malformation.
Reasons for AAA repair, procedural, and post-procedural outcomes details are shown in Table 3 . Of note, only five patients were repaired in an open fashion in our cohort of AAA with head imaging, and there were in total three deaths with a mortality rate of 0.7%. The only significant differences among AAA and AAA + IA groups were the estimated blood loss, transfused red blood cell units and fresh frozen plasma units; which were all driven by one patient who presented with a ruptured 74-mm right common iliac artery aneurysm, and the estimated blood loss was calculated to be 12 L requiring 20 units of red blood cells, 10 units of fresh frozen plasma, 10 units of cryoprecipitate, 10 units of platelets, and recycling of 1,500 mL of blood from the cell saver. This patient expired within 24 hours of the emergent operation due to ventricular tachycardia, and cardiopulmonary resuscitation was performed to no avail.
Table 3. Procedural and postoperative outcomes after abdominal aortic aneurysm repair in patients without intracranial aneurysms ( n = 384) and with intracranial aneurysms ( n = 37) .
| All patients with abdominal aortic aneurysms ( n = 421) |
Patients with abdominal aortic aneurysm without intracranial aneurysms ( n = 384) | Patients with abdominal aortic aneurysm with intracranial aneurysm ( n = 37) | p | |
|---|---|---|---|---|
| n (%)/Mean ± Standard deviation | n (%)/Mean ± Standard deviation | n (%)/Mean ± Standard deviation | ||
| Reason for operation ( n ) | ||||
| Size | 384 (91.2%) | 352 (91.7%) | 32 (86.5%) | |
| Ruptured | 20 (4.8%) | 18 (4.7%) | 2 (5.4%) | |
| Symptomatic, however intact | 17 (4.0%) | 14 (3.6%) | 3 (8.1%) | 0.28 a |
| Type of surgery ( n ) | ||||
| Elective | 394 (94.3%) | 360 (93.8%) | 34 (91.9%) | |
| Emergent | 27 (5.7%) | 24 (6.2%) | 3 (8.1%) | 0.72 a |
| Surgical technique ( n ) | ||||
| Endovascular | 416 (98.8%) | 379 (98.7%) | 37 (100%) | |
| Open | 5 (1.2%) | 5 (1.3%) | 0 (0%) | 1.0 a |
| Procedural in/out | ||||
| Estimated blood loss (mL) | 339.4 ± 1051.5 | 295.0 ± 790.5 | 911.8 ± 2704.0 | 0.0027 b |
| Transfused RBC (units) | 0.3 ± 1.5 | 0.2 ± 1.0 | 0.9 ± 3.7 | 0.005 b |
| Transfused platelet (units) | 0.03 ± 0.23 | 0.03 ± 0.23 | 0.05 ± 0.22 | 0.12 b |
| Transfused FFP (units) | 0.09 ± 0.73 | 0.06 ± 0.50 | 0.4 ± 1.8 | 0.006 b |
| Use of cell saver | 13 (3.1%) | 10 (2.6%) | 3 (8.1%) | 0.10 a |
| Postoperative complications ( n ) | ||||
| Anemia requiring transfusion | 18 (4.3%) | 17 (4.4%) | 1 (2.7%) | 1.00 a |
| Myocardial infarction | 6 (1.4%) | 5 (1.3%) | 1 (2.7%) | 0.43 a |
| Ischemic colitis | 4 (1.0%) | 3 (0.8%) | 1 (2.7%) | 0.31 a |
| Reintubation | 3 (0.7%) | 3 (0.8%) | 0 (0%) | 1.0 a |
| Stroke | 1 (0.2%) | 1 (0.3%) | 0 (0%) | 1.0 a |
| Wound infection | 1 (0.2%) | 1 (0.3%) | 0 (0%) | 1.0 a |
| Length of intensive care unit stay (d) | 0.5 ± 2.7 | 0.5 ± 2.8 | 0.3 ± 0.8 | 0.14 b |
| Length of hospital stay (d) | 2.9 ± 6.8 | 2.9 ± 7.0 | 3.0 ± 4.3 | 0.54 b |
| Discharge disposition | ||||
| Home/self-care | 376 (89.3%) | 343 (89.3%) | 33 (89.2%) | |
| Skilled nursing facility | 27 (6.4%) | 24 (6.3%) | 3 (8.1%) | 0.72 a |
| In-hospital death ( n ) | 3 (0.7%) | 2 (0.5%) | 1 (2.7%) | 0.24 a |
Abbreviations: AAA, abdominal aortic aneurysm; FFP, fresh frozen plasma; IA, intracranial aneurysms; ICU, intensive care unit; RBC, red blood cells.
Note: Categorical characteristics are presented as percentage (number of patients with characteristic/number of patients with data available). Continuous characteristics are presented as median (minimum–maximum, number of patients with data available).
Fisher's exact test.
Wilcoxon rank sum test.
Patients with AAA and Positive Head Imaging with IA
The exact location of all IAs is shown in Fig. 1 . The mean aneurysm size at the time of diagnosis was 4.6 ± 3.5 mm. A total of 30 (81%) patients were men. Six patients with IA underwent treatment, four for ruptured IAs and two unruptured ( Table 4 ). They were all diagnosed prior to AAA repair. Time from diagnosis of IA to AAA repair was 16.4 ± 11.0 years (range: 2.2–33.1 years). Treatment included five clippings and one coil-assisted stenting.
Fig. 1.
Location of all intracranial aneurysms. (Reproduced with permission of Mayo Foundation for Medical Education and Research. All rights reserved.)
Table 4. All patients with AAA and IA repair.
| Patient, sex | Reason for abdominal imaging | Month and year of diagnosis and size of AAA | Month and year of surgical treatment for AAA | AAA size (mm) and condition | Reason for head imaging | Month and year of diagnosis of IA | Month and year of surgical treatment for IA | IA size (mm) and condition |
|---|---|---|---|---|---|---|---|---|
| Patient 1, male | Screening ultrasound due to 60 pack/y smoking history. | August 2003 38 mm |
October 2010 | AAA 55 mm Unruptured and successfully repaired |
Neurologist suspected IA with known history of AAA | May 2008 | September 2008 | 10.5 mm Unruptured |
| Patient 2, male | Presentation to the emergency department with gallstone pancreatitis, which prompted computed tomography of the abdomen. | October 2010 30 mm |
December 2010 | AAA 30 mm Right common iliac artery aneurysm 56 mm Unruptured and successfully repaired |
Ruptured IA | December 1994 | December 1994 | Ruptured |
| Patient 3, male | Presentation to the emergency department with chest pain, which prompted computed tomography of the abdomen. | June 2009 36 mm |
February 2016 | AAA 51 mm Unruptured and successfully repaired |
Ruptured IA | August 16, 1991 | August 1991 | Ruptured |
| Patient 4, male | Presentation to the emergency department with hypotension and abdominal pain, which prompted computed tomography of the abdomen. | December 2017 60 mm |
December 2017 | Right internal iliac artery aneurysm 60 mm Ruptured and successfully repaired |
Suspected stroke | March 21, 2016 | July 2016 | 5.4 mm Unruptured |
| Patient 5, female | Participation in the life line screening program. | April 2015 35 mm |
January 2018 | AAA 49 mm RCIA 22 mm Unruptured and successfully repaired |
Ruptured IA | 1985 | 1985 | Ruptured |
| Patient 6, male | Presentation to the emergency department with hypotension and abdominal pain, which prompted computed tomography of the abdomen. | November 2018 35 mm |
November 2018 | AAA 35 mm Right common iliac artery aneurysm 74 mm Ruptured and died within 24 h |
Ruptured IA | October 2005 | October 2005 | Ruptured |
Abbreviations: AAA, abdominal aortic aneurysms; IA, intracranial aneurysms; RCIA, right common iliac artery.
Patient 1 had a positive abdominal ultrasound screening as part of the United States Preventive Services Task Force (USPSTF) recommendations 16 in August 2003. Subsequently, a neurology consultation for neck pain in May 2008 recommended screening MRA of the head, which was positive for a 10.5-mm unruptured right A1/A2 segment in the anterior cerebral artery aneurysm. This aneurysm was electively repaired by stent-assisted coiling in September 2008 ( Fig. 1 ).
Patient 2 underwent repair on an emergent basis via clipping in December 1994 of a ruptured right A1 segment of the anterior cerebral artery. He subsequently presented to the emergency department (ED) in October 2010 with abdominal pain and was found to have gallstone pancreatitis on CT imaging. Concurrently in this study, he was found to have a 30-mm AAA and a 56-mm right common iliac artery aneurysm, which underwent successful repair in December 2010.
Patient 3 underwent repair on an emergent basis via clipping in August 1991 of a ruptured right M1 segment of the middle cerebral artery. He subsequently presented to the ED in June 2009 with chest pain. CT of the abdomen obtained during this visit demonstrated a 36-mm AAA, which was followed by our vascular surgeons until February 2016, at which point it underwent successful elective endovascular repair at a diameter of 51 mm.
Patient 4 underwent CTA of the head for a suspected stroke in March 2016, which demonstrated a 5.4-mm unruptured anterior communicating artery aneurysm. This underwent repair by clipping in July 2016. He subsequently presented to the ED with abdominal pain and hypotension, which prompted CT of the abdomen. This study demonstrated a ruptured right internal iliac artery aneurysm of 60 mm in diameter, which underwent successful endovascular repair.
Patient 5 underwent repair on an emergent basis via clipping in 1985 of a ruptured left middle cerebral artery bifurcation aneurysm. She then participated in a Life Line Screening Program that included an abdominal ultrasound, which demonstrated a 35-mm AAA. She was then followed by our vascular surgeons until January 2018 at which point, the AAA underwent successful elective endovascular repair at a diameter of 49 mm.
Patient 6 underwent repair on an emergent basis via clipping in October 2005 of a ruptured right middle cerebral artery trifurcation aneurysm. He subsequently presented to the ED in November 2018 with abdominal pain and hypotension. CT imaging of the abdomen obtained during this visit demonstrated a ruptured 74-mm right common iliac artery aneurysm. He underwent successful repair; however, he expired within 24 hours from the emergent operation due to ventricular tachycardia and unsuccessful cardiopulmonary resuscitation.
Patients with AAA and Head Imaging Matched to Non-AAA Patients
Patient characteristics of matched patients are summarized in Table 5 for cases and controls. IAs were identified in 8.8% of AAA patients (37/421) and in 3.1% of non-AAA patients (13/421) for an OR = 3.18; 95% CI, 1.62–6.27; p < 0.001. The three most common reasons for obtaining cross-sectional head imaging in our control patients included suspicion for transient ischemic attack/stroke/subarachnoid hemorrhage ( n = 160), known intracranial or carotid artery stenosis ( n = 67), and intracranial neoplasm ( n = 34). Other reasons for imaging are shown in Table 2 . The most challenging characteristic to match for was age. Therefore, the criterion for age matching was broadened to include ± 3 years.
Table 5. Patients characteristics of matched patients.
| Variable | AAA patients with head imaging ( n = 421) |
Matched patients non-AAA with head imaging ( n = 421) |
|---|---|---|
| Year of head imaging, no. (%) | ||
| 1994–1999 | 14 (3.3%) | 14 (3.3%) |
| 2000–2009 | 180 (42.8%) | 180 (42.8%) |
| 2010–2019 | 227 (53.9%) | 227 (53.9%) |
| Site | ||
| Florida | 71 (16.9%) | 71 (16.9%) |
| Arizona | 44 (10.5%) | 44 (10.5%) |
| Minnesota | 306 (72.7%) | 306 (72.7%) |
| Age, mean (standard deviation) | 75.9 (7.8) | 76.0 (7.8) |
| Male sex, n (%) | 371 (88.1%) | 372 (88.4%) |
| Smoking history, n (%) | ||
| Never | 69 (16.4%) | 69 (16.4%) |
| Prior | 308 (73.2%) | 308 (73.2%) |
| Current | 44 (10.5%) | 44 (10.5%) |
| Imaging type, n (%) | ||
| CT + contrast | 10 (2.4%) | 10 (2.4%) |
| MRI + contrast | 132 (31.4%) | 132 (31.4%) |
| CTA | 63 (15.0%) | 63 (15.0%) |
| MRA | 216 (51.3%) | 216 (51.3%) |
Abbreviations: AAA, abdominal aortic aneurysms; CT, computed tomography; CTA, computed tomography angiography; MRA, magnetic resonance angiography; MRI, magnetic resonance imaging.
Discussion
Several single-center case series have reported a prevalence of IA and AAA to range from 2.2 to 20.3%. 10 11 12 13 14 Most recently, a population-based study, by Wang et al demonstrated a significant increase in the rate of IA among surgical aortic aneurysm patients compared with the general population. 17 The study however, includes all aortic aneurysms. Our specific interest was in discerning the difference in prevalence following those surgical patients with AAA and available head imaging. In our review, the prevalence of IA in surgical AAA patients who had head or intracranial arterial imaging was found to be 8.8%. Furthermore, we found that patients with both AAA and IA have higher rates of coronary artery disease, prior coronary artery bypass surgery, and congestive heart failure, which is also supported by genome-wide sequencing analysis associations between myocardial infarction, AAA, and IA. 18 This association with coronary artery disease may have implications for perioperative management of patients known to have both intracranial and aortic aneurysms. Another single center review published by Shin et al 14 was able to determine a co-prevalence of 10.8% for individuals with aortic aneurysms and available head imaging with a positive IA. In our study, we were able to specifically follow those patients with infrarenal AAA and the co-prevalence of IA in specific cohort. In our study, however, we were able to match our co-prevalence group in a 1:1 ratio to non-AAA controls ( Table 5 ) using the following criteria: age, sex, type of head imaging, year of head imaging, location at which head imaging was obtained, and smoking history to assess for the odds ratio for having an IA detected on head imaging, which takes the knowledge from the previously published manuscript by Shin et al, 14 a step further than determining co-prevalence. We were able to determine an OR of 3.18; 95% CI, 1.62–6.27, p < 0.001. One of our interesting findings comes from the analysis of those patients who underwent treatment for IA ( Table 4 ). All six patients had IA diagnosed prior to AAA repair and in four instances, they presented as ruptured IA. Only one patient was diagnosed with AAA prior to IA diagnosis due to routine screening ultrasound for AAA as recommended by the USPSTF because of his age and significant smoking history. 16 A second patient participated voluntarily in a Life Line Screening Program that included an abdominal ultrasound and benefited from early diagnosis and follow-up surveillance for AAA. The remaining four individuals presented to the ED either for unrelated medical problems or an acutely ruptured aortic aneurysm. Had these individuals undergone screening ultrasound of the abdomen as we propose in our previous study, 15 these AAA would have been diagnosed earlier at a smaller size and followed under surveillance by our vascular surgeons. In two instances early detection and elective repair of AAA could have prevented acute rupture and in one instance, death.
Humphrey and Taylor 19 recognized the histopathological and biomechanical characteristics of these two aneurysms and suggested using computational tools and models to describe the evolving geometry, nonlinear wall properties, and hemodynamics responsible for possible rupture of aneurysms during each cardiac cycle to aid the clinician on how to better understand each aneurysm and which one should be intervened upon earlier than later and which surgical technique will better serve the patient for a good outcome. We believe that the presented evidence in our manuscript suggests that there may be utility to screening for AAA in those patients with IA. Large prospective studies of systematic screening of AAA in patients with IA that include patient-centered outcomes are justified.
Limitations
Our study's main limitations include the fact that, this is a retrospective chart review of a highly selected group of patients including those that underwent AAA repair. Furthermore, not all patients undergoing AAA repair underwent head imaging and finally, our control group is not based on a random selection of healthy individuals, but include those patients have legitimate reasons for cross-sectional head imaging. Therefore, cautious interpretation of our conclusions is warranted.
Conclusion
Co-prevalence of IA in this retrospective review among patients with AAA was 8.8%. This rate is higher than detected in a randomly sampled population without known AAA who underwent head imaging for various indications. Our conditional logistic regression model using non-AAA-matched patients confirms this higher prevalence. All IAs were diagnosed prior to AAA repair. Surveillance for AAA after IA treatment could have prevented two AAA ruptures and one death. This review would suggest a merit to screening for AAA in individuals with IA.
Article Highlights
Type of Research
Retrospective case–control study using an institutional Vascular Surgery database from January 1998 to December 2018.
Key Findings
The prevalence of IA within AAA patients is calculated to be 8.8%. Further, the OR of finding IA in the AAA population was 3.18; 95% CI, 1.62–6.27, p < 0.001.
Take Home Message
This review suggests a merit to screening for AAA in individuals with IA.
Table of Contents Summary
Co-prevalence of IAs among patients with AAAs was 8.8%. This rate was over three times higher than in the general population (OR 3.18; 95% CI, 1.62–6.27, p < 0.001). Patients with AAAs may be at sufficiently high risk to merit screening for IAs.
Footnotes
Conflict of Interest None declared.
References
- 1.Vlak M H, Algra A, Brandenburg R, Rinkel G J. Prevalence of unruptured intracranial aneurysms, with emphasis on sex, age, comorbidity, country, and time period: a systematic review and meta-analysis. Lancet Neurol. 2011;10(07):626–636. doi: 10.1016/S1474-4422(11)70109-0. [DOI] [PubMed] [Google Scholar]
- 2.Sidawy A PB. 2019. Rutherford's Vascular Surgery and Endovascular Therapy. 9th ed; pp. 875–884. [Google Scholar]
- 3.American Heart Association/American Stroke Association Stroke Council ; American Heart Association/American Stroke Association High Blood Pressure Research Council ; Quality of Care and Outcomes in Research Interdisciplinary Working Group . Broderick J, Connolly S, Feldmann E. Guidelines for the management of spontaneous intracerebral hemorrhage in adults: 2007 update: a guideline from the American Heart Association/American Stroke Association Stroke Council, High Blood Pressure Research Council, and the Quality of Care and Outcomes in Research Interdisciplinary Working Group. Circulation. 2007;116(16):e391–e413. doi: 10.1161/CIRCULATIONAHA.107.183689. [DOI] [PubMed] [Google Scholar]
- 4.American Heart Association Stroke Council ; Council on Cardiovascular Radiology and Intervention ; Council on Cardiovascular Nursing ; Council on Cardiovascular Surgery and Anesthesia ; Council on Clinical Cardiology . Connolly E S, Jr, Rabinstein A A, Carhuapoma J R. Guidelines for the management of aneurysmal subarachnoid hemorrhage: a guideline for healthcare professionals from the American Heart Association/American Stroke Association. Stroke. 2012;43(06):1711–1737. doi: 10.1161/STR.0b013e3182587839. [DOI] [PubMed] [Google Scholar]
- 5.Pae S J, Carr J A. Ruptured abdominal aortic aneurysms in community practice: age and operative variables predict survival. Am Surg. 2007;73(09):912–916. [PubMed] [Google Scholar]
- 6.Schechter M A, Pascarella L, Thomas S, McCann R L, Mureebe L. Endovascular and open repair of ruptured infrarenal aortic aneurysms at a tertiary care center. Ann Vasc Surg. 2017;41:83–88. doi: 10.1016/j.avsg.2016.10.037. [DOI] [PubMed] [Google Scholar]
- 7.Gretarsdottir S, Baas A F, Thorleifsson G. Genome-wide association study identifies a sequence variant within the DAB2IP gene conferring susceptibility to abdominal aortic aneurysm. Nat Genet. 2010;42(08):692–697. doi: 10.1038/ng.622. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.van 't Hof F N, Ruigrok Y M, Baas A F. Impact of inherited genetic variants associated with lipid profile, hypertension, and coronary artery disease on the risk of intracranial and abdominal aortic aneurysms. Circ Cardiovasc Genet. 2013;6(03):264–270. doi: 10.1161/CIRCGENETICS.113.000022. [DOI] [PubMed] [Google Scholar]
- 9.Aneurysm Consortium ; Vascular Research Consortium of New Zealand . van 't Hof F N, Ruigrok Y M, Lee C H. Shared genetic risk factors of intracranial, abdominal, and thoracic aneurysms. J Am Heart Assoc. 2016;5(07):e002603. doi: 10.1161/JAHA.115.002603. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 10.Kuzmik G A, Feldman M, Tranquilli M, Rizzo J A, Johnson M, Elefteriades J A. Concurrent intracranial and thoracic aortic aneurysms. Am J Cardiol. 2010;105(03):417–420. doi: 10.1016/j.amjcard.2009.09.049. [DOI] [PubMed] [Google Scholar]
- 11.Lee D, Ahn S J, Cho E S. High prevalence of intracranial aneurysms in patients with aortic dissection or aneurysm: feasibility of extended aorta CT angiography with involvement of intracranial arteries. J Neurointerv Surg. 2017;9(10):1017–1021. doi: 10.1136/neurintsurg-2016-012619. [DOI] [PubMed] [Google Scholar]
- 12.Norrgård O, Angqvist K A, Fodstad H, Forssell A, Lindberg M.Co-existence of abdominal aortic aneurysms and intracranial aneurysms Acta Neurochir (Wien) 198787(1-2):34–39. [DOI] [PubMed] [Google Scholar]
- 13.Rouchaud A, Brandt M D, Rydberg A M. Prevalence of intracranial aneurysms in patients with aortic aneurysms. AJNR Am J Neuroradiol. 2016;37(09):1664–1668. doi: 10.3174/ajnr.A4827. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 14.Shin Y W, Jung K H, Moon J. Site-specific relationship between intracranial aneurysm and aortic aneurysm. Stroke. 2015;46(07):1993–1996. doi: 10.1161/STROKEAHA.115.009254. [DOI] [PubMed] [Google Scholar]
- 15.Erben Y BK, Freeman W D, Lin M.Co-prevalence of abdominal aortic aneurysms in patients with intracranial aneurysms may support routine screening with abdominal ultrasound: from the brain and aortic aneurysms study (BAAS) Neurocrit Care 2019. Sep 25. 10.1007/s12028-019-00828-y [DOI] [PubMed] [Google Scholar]
- 16.https://www.uspreventiveservicestaskforce.org/Page/Document/UpdateSummaryFinal/abdominal-aortic-aneurysm-screening https://www.uspreventiveservicestaskforce.org/Page/Document/UpdateSummaryFinal/abdominal-aortic-aneurysm-screening
- 17.Wang J C, Chien W C, Chung C H. Association between surgical repair of aortic aneurysms and the diagnosis of intracranial aneurysms. J Vasc Surg. 2020;71(02):481–489. doi: 10.1016/j.jvs.2019.04.466. [DOI] [PubMed] [Google Scholar]
- 18.Helgadottir A, Thorleifsson G, Magnusson K P. The same sequence variant on 9p21 associates with myocardial infarction, abdominal aortic aneurysm and intracranial aneurysm. Nat Genet. 2008;40(02):217–224. doi: 10.1038/ng.72. [DOI] [PubMed] [Google Scholar]
- 19.Humphrey J D, Taylor C A. Intracranial and abdominal aortic aneurysms: similarities, differences, and need for a new class of computational models. Annu Rev Biomed Eng. 2008;10:221–246. doi: 10.1146/annurev.bioeng.10.061807.160439. [DOI] [PMC free article] [PubMed] [Google Scholar]