Ruptured abdominal aortic aneurysm (rAAA) is the 15th leading cause of death in the United States accounting for more than 8500 hospital deaths per year [
In an effort to reduce the number of AAA-related deaths, the United States Congress approved the Screening Abdominal Aortic Aneurysms Very Efficiently (SAAAVE) Act in January 2007. The SAAAVE Act permits a single screening ultrasound examination as part of the “Welcome to Medicare” package for patients with defined risk factors for AAA. Specifically, males between the age of 65 and 75 years who have smoked greater than 100 cigarettes or patients of any age/gender with a strong family history are eligible for this screening examination [
Despite the introduction of the SAAAVE Act, screening for AAA remains underutilized with less than 10,000 beneficiaries being screened in 2007 [
This study was approved by the Geisinger Medical Center Institutional Review Board. All patients presenting to Geisinger Medical Center with a diagnosis of rAAA between January 1, 2004 and December 31, 2010 were identified by Current Procedural Terminology (CPT) and International Classification of Diseases 9th revision (ICD-9) codes. These selected patients were then retrospectively reviewed through the use of the electronic health record (EHR) and a clinical decision intelligence system (CDIS) data warehouse to verify the correct diagnosis. The CDIS data warehouse at Geisinger Medical Center receives updated data every 24 hours from the EHR as well as regular data updates from multiple other source systems, including hospital billing, financial decision support, insurance claims, and high-use third-party reference datasets. Any patient with a rAAA who was evaluated in an outpatient setting within 6 months of the date of rupture was included in the study.
Demographics, cardiovascular risk factors, physical exam findings, prior radiologic evaluations, and preadmission medications were obtained from the EHR and/or CDIS. In addition, radiographic imaging with abdominal ultrasound (Duplex) and computed tomography (CT) scan prior to aneurysm rupture was independently reviewed separately by a vascular surgeon and a radiologist for each patient to establish whether the diagnosis of AAA was previously established or overlooked. Aneurysm diameter (the greatest transverse measurement perpendicular to the center line) at the time of rupture was measured by direct review of the radiographic images or, if not available, it was taken from the operating surgeon’s documentation within the EHR. Data were analyzed using Society for Vascular Surgery reporting standards [
Between January 1, 2004 and December 31, 2010, 149 patients presented to Geisinger Medical Center with a diagnosis of rAAA. Demographics and cardiovascular risk factors are detailed in Table
Demographics, medical comorbidities, and current medical therapy in 52 patients evaluated in the outpatient setting ≤6 months of diagnosis of ruptured AAA.
Variable | Mean ± SD | Total 52 |
---|---|---|
| ||
Age (years) | 73.5 ± 8.9 | |
Male | 36 (69) | |
Female | 16 (31) | |
Hypertension | 42 (80.8) | |
Peripheral vascular disease | 13 (25) | |
Diabetes | 15 (28.8) | |
Hyperlipidemia | 32 (61.5) | |
Coronary artery disease | 27 (51.9) | |
Chronic obstructive pulmonary disease | 20 (38.5) | |
Congestive heart failure | 5 (9.6) | |
Chronic kidney disease | 19 (36.5) | |
Smoking | ||
Never | 4 (7.7) | |
Current | 21 (40.4) | |
Quit | 16 (30.8) | |
Unknown | 11 (21.1) | |
Aspirin | 30 (55.6) | |
Clopidogrel | 5 (9.3) | |
Beta blocker | 28 (51.9) | |
Statin | 27 (50) | |
ACEI/ARB | 24 (44.4) |
AAA: abdominal aortic aneurysm; ACEI: angiotensin converting enzyme inhibitor; ARB: angiotensin receptor blocker; chronic kidney disease, GFR < 60.
Of the 149 patients presenting with a rAAA, 52 patients (34.9%) had an EHR documented outpatient evaluation in a Geisinger Health System ambulatory care setting within 6 months of the date of rupture, and these 52 patients form the basis of this study (Figure
Medical specialty and average time (days) from ambulatory care visit for 52 patients evaluated ≤6 months prior to diagnosis of ruptured AAA.
Variable | Days (range) | Total |
---|---|---|
| ||
Outpatient visit—rAAA | 52.4 (0–166) | |
PCP | 30 (57.7) | |
Cardiology | 7 (13.5) | |
Ophthalmology | 4 (7.7) | |
Vascular Surgery | 3 (5.8) | |
Dermatology | 2 (3.8) | |
Hematology/Oncology | 1 (1.9) | |
Urology | 1 (1.9) | |
Infectious disease | 1 (1.9) | |
Nephrology | 1 (1.9) | |
Cardiothoracic | 1 (1.9) | |
Orthopedics | 1 (1.9) |
PCP: primary care provider; AAA: abdominal aortic aneurysm.
Comparison of outpatient physical exams findings in 38 patients versus vascular surgery fellow physical examination findings in 52 patients.
Variable | ACP total 38 | VSF total 52 |
|
---|---|---|---|
|
| ||
Tenderness | 2 (3.8) | 12 (23.1) | .008 |
Pulsatile mass | 1 (1.9) | 10 (19) | .004 |
Tenderness + pulsatile mass | 1 (1.9) | 16 (30.8) | <.0001 |
| |||
Total exam | 4 (7.7) | 38 (73.1) | <.00001 |
ACP: ambulatory care provider in outpatient setting; VSF: vascular surgery fellow in emergency department setting.
Reference diagram of 149 patients diagnosed with ruptured abdominal aortic aneurysm and availability of both inpatient and outpatient complete EHR data. CPT, Current Procedural Terminology; ICD-9, International Classification of Diseases ninth revision; EHR, electronic health record.
The 52 study group patients had a mean BMI of 28.2 kg/m2 and a mean AAA diameter of 76 mm. BMI and AAA size were evaluated in patients with and without palpable pulsatile masses in the emergency department (Table
BMI, AAA size, and vascular fellow examination for pulsatile abdominal mass of the 52 study patient presenting with ruptured AAA.
Variable | Mean ± SD | Range |
---|---|---|
BMI (kg/m2) without pulsatile mass | 28.9 ± 6.0 | 16.1–52.0 |
BMI (kg/m2) with pulsatile mass | 27.7 ± 7.1 | 16.1–52.0 |
AAA size (mm) without pulsatile mass | 73.2 ± 18.4 | 44.0–120 |
AAA size (mm) with pulsatile mass | 79.5 ± 18.4 | 55.0–120 |
BMI: body mass index; AAA: abdominal aortic aneurysm.
Twenty-one (40.3%) patients underwent 27 radiographic studies (Duplex and/or CT scan) of the abdomen and/or pelvis prior to the date of rupture. Thirteen of these patients had radiographic evidence of an AAA within 1 year of presenting with an rAAA and 8 patients had radiographic evidence of an AAA more than a year prior to rupture. Three patients had Duplex alone, 12 patients had CT scan alone, and 6 patients underwent both imaging modalities. Twelve of these 21 patients were referred and evaluated in the vascular surgery clinic based on the results of these imaging studies. Of these 12 patients, 4 declined repair, 4 were followed for AAA sizes <50 mm, 2 patients were offered repair and ruptured in the interim (2 weeks and 3 weeks) after evaluation, and 2 patients (one with AAA diameter of 40 mm and the other with AAA diameter of 67 mm at the time of diagnosis) were lost to followup. The remaining 9 patients were not evaluated in the vascular surgery clinic prior to the date of rupture. Reasons for the lack of referral could not be determined based on review of the EHR.
Per the current SAAAVE Act criteria, only 9/52 (17.3%) study patients would have been eligible for the Welcome to Medicare screening aortic ultrasound (Table
SAAAVE Act eligibility in 52 study patients with ruptured AAA at the time of presentation.
Variable | Total (52) | Smoking | FHx | Eligible |
---|---|---|---|---|
|
|
|
| |
Age (male) | ||||
65–75 | 10 (19.2) | 7 | 0 | 7 (13.5) |
<65 | 7 (13.5) | 5 | 0 | 0 |
>75 | 19 (36.5) | 11 | 1 | 1 (1.9) |
Female | 16 (30.8) | 13 | 1 | 1 (1.9) |
| ||||
Total | (17.3) |
AAA: abdominal aortic aneurysm; Smoking: smoking history (>100 cigarettes); FHx: family history.
The aim of this study was to investigate whether current screening guidelines, in conjunction with routine ambulatory medical care evaluation, are an effective way to identify as well as screen patients at risk for AAA. Our review identified that only 17% of patients who presented to our institution with an rAAA would have been eligible for a screening ultrasound based upon the SAAAVE Act criteria at the time of rupture. These findings suggest that current AAA screening guidelines are not adequate to make a substantial reduction in aneurysm related mortality. Given the high mortality associated with rAAA, expanding screening criteria may have enabled earlier detection in the remaining 83% of our patients, thus providing the opportunity for referral and elective repair.
Our findings, while being of great concern, also fail to account for those who qualify for an aneurysm screening but do not utilize it. As others have documented, achieving a high initial rate of screening attendance, along with a low elective operative mortality rate, is vital for any meaningful decrease in AAA-related mortality [
Moreover, we also need to educate primary care providers about the specialty of vascular surgery and the services we provide, for patient referral to a vascular surgeon is an important step in the elective AAA repair process. It is a curious finding that 40% of our study patients had radiographic evidence of AAA prior to rupture, but many were not referred and evaluated in the vascular surgery clinic. Similar findings were reported by MacDonald et al. who retrospectively identified a known AAA in 34/104 (33%) patients presenting with rAAA [
Another interesting finding of our investigation, albeit less novel, is that physical examination (PE) is not adequate to diagnose an AAA. In the outpatient ambulatory medical setting, despite most of these 52 patients have been seen and evaluated by primary care physicians and cardiologists within 6 months of rupture, the diagnosis of AAA based on physical exam was rare. These findings were somewhat anticipated and are not meant to be an indictment against our medical colleagues, but rather emphasize the fact that in routine real world experience, patients at risk for AAA often go undiagnosed when simple history and physical exam are employed in the outpatient care setting. Even in the experienced hands of vascular surgery fellows concerned about the diagnosis of AAA, physical examination was only accurate about 50% of the time on the actual day of rupture. Perhaps altered hemodynamics and abdominal distention played a role in masking the physical exam findings by the vascular fellows in the emergency department, but the results nonetheless further emphasize that physical exam alone is not reliable in diagnosing rAAA even in this population of patients with large aneurysms and modest BMI values. Other authors have reported similar findings. Specifically, Anjum et al. described the difficulty of aortic palpation in obese patients prior to elective open AAA repair in 1995 [
Lastly, a significant gender issue exists regarding AAA screening for women resulting in missed opportunities for earlier detection. Approximately 30% of our study patients were women, but only one of these women (based on family history) would have been SAAAVE Act eligible. Multiple articles have documented the lower prevalence of AAA in women versus men. In 2007, DeRubertis et al. came to a similar conclusion documenting AAA prevalence rates of 0.7% and 3.9% for women and men, respectively [
There are several limitations to our study. The total number of study group patients is small due to our exclusion of patients not evaluated within 6 months of the date of rupture. It is also quite likely that many of the remaining 97/149 patients were in fact seen in the ambulatory setting within 6 months of rupture but were outside of our health system and therefore not eligible for the study due to a lack of complete outpatient EHR data. In regard to the accuracy of the outpatient visit physical examination findings, to be fair to the primary care physicians and cardiologists, many of the patients were likely being evaluated for other medical problems and underwent focused exams of other organ systems, thus accounting for the fact that only 36/52 patients had outpatient abdominal examinations documented in the EHR. Also, the physical examinations performed in the emergent department by the vascular fellows were biased due to the vascular fellows’ awareness of the likely diagnosis of rAAA. Lastly, this is a retrospective study without any comparison group or potential for randomization.
Routine medical evaluation in the primary care setting fails to diagnose patients at risk for ruptured abdominal aortic aneurysm. Improved utilization of the one-time screening ultrasound exam covered by Medicare in the SAAAVE Act and continued education of our primary care colleagues are needed in order to increase the diagnostic yield for detecting AAA in high risk patients.
The authors would like to thank Jove Graham and his research staff from the Henry Hood Center for Health Research at Geisinger Medical Center for efficiently facilitating the data collection process for this project.