Faculty Bibliography

Bow Hunter's syndrome is a condition in which patients experience vertebrobasilar symptoms on head turn. It may be a consequence of intrinsic factors such as atherosclerosis, or it may be secondary to mechanical compression. Most commonly, this occurs at the level of C2 or above. We present two rare cases of Bow Hunter's syndrome secondary to mechanical compression at the level of C7. Discussed are the anatomic conditions leading to this syndrome in these two patients, the methodology for confirming the diagnosis, and the successful management by partial resection of the transverse processes compressing the vertebral arteries

OBJECTIVE:: Current screening recommendations for abdominal aortic aneurysm (AAA) target >3-cm diameter aneurysms in ever-smoking 65- to 75-year-old males. However, more than 50% of AAA ruptures occur in individuals outside this patient cohort, and only a subset of AAAs detected are large enough to warrant surgery. In this analysis, we evaluated more than 3 million screened individuals and developed a scoring tool to identify >/=5-cm diameter AAAs in the entire population at risk. METHODS:: Between 2003 and 2008, demographics and risk factors were collected from 3.1 million people undergoing ultrasound screening for AAA by Life Line Screening, Inc. Using multivariable logistic regression analysis, we identified risk factors and developed a scoring system to predict the presence of >/=5-cm diameter AAAs. RESULTS:: Smoking had a profound influence on the risk of AAA, which increased with number of cigarettes smoked and years of smoking, and decreased following smoking cessation. Novel findings included a protective effect of exercise, normal weight, and Black/Hispanic race/ethnicity. Using these and other factors, the scoring system provided good predictive accuracy (C-statistic = 0.82), when tested against the validation subset of the study cohort. The model predicts the presence of 121,000 >/=5 cm AAA in the US population (prevalence: 0.14%). Demonstrating the inadequacy of the current screening recommendations, only 35% of these aneurysms were among males aged 65 to 75 years. CONCLUSIONS:: Based on the largest cohort of patients ever screened for AAA, we developed a screening strategy that can identify large AAAs in a broad population of individuals at risk

OBJECTIVE: With the decline of diagnostic angiography, clinicians increasingly rely upon duplex scan criteria to select appropriate asymptomatic candidates for carotid intervention. Some recent trials have enrolled patients for intervention based upon end diastolic velocities (EDVs) as low as 100 cm/second, and peak systolic velocities (PSVs) as low as 230 cm/second. In as much as we have used more selective duplex scan criteria, we reviewed the course of asymptomatic patients who had EDVs from 100 to 124 cm/second. METHODS: Of the patients evaluated in our Intersocietal Commission for the Accreditation of Vascular Laboratories (ICAVL) accredited laboratory from 2002 to 2007, 144 patients had an EDV 100 to 124 cm/second. Of these, 47 patients underwent initial carotid intervention for concomitant symptoms (10), contralateral occlusion (3), or other imaging findings felt to warrant intervention. The remaining 97 asymptomatic patients were followed. One patient had both arteries fall within this EDV range. The mean follow-up for the 98 arteries was 29.1 months (range, 2-116 months). RESULTS: Five patients (5.2%) developed ipsilateral symptoms consisting of one stroke and four transient ischemic attacks (TIAs), at a mean time of 35.3 months (range, 12-58 months). Twenty-six patients (26.8%), including 3 who also developed ipsilateral symptoms, progressed to having an EDV of >/= 125 cm/second at a mean time of 24 months (range, 2-58). Two of these (2.1%) progressed directly to occlusion without symptoms and with no documented interim worsening of stenosis. CONCLUSION: For asymptomatic individuals with an initial EDV of 100 to 124 cm/second, the risk of ipsilateral stroke is small and, therefore, medical management is appropriate in most cases. However, the risk of progression to a more severe degree of stenosis, often warranting carotid intervention, is clinically meaningful. Yearly duplex scan follow-up is necessary to assess disease progression in this patient cohort

OBJECTIVE: Prophylactic atropine traditionally has been used to prevent CAS-associated hemodynamic depression. Glycopyrrolate may serve as an alternative with decreased cardiac effects. This study aims to compare the efficacy of prophylactic glycopyrrolate to atropine in preventing CAS-induced hemodynamic instability and cardiac complications. METHODS: 115 consecutive CAS patients from 2004-2010 were evaluated. Primary endpoints were stroke, MI, bradycardia (HR<60 beats/min), and hypotension (systolic BP <90 mm Hg). Additional outcomes included tachycardia (HR >100 beats/min), hypertension (systolic BP >160 mm Hg), pre- and postoperative systolic BP difference, vasopressor use, arrhythmias, cardiac enzyme elevations, and access site complications. RESULTS: Of 115 patients, 65 (56.5%) patients who received atropine or glycopyrrolate prior to CAS were analyzed [40 (61.5%) patients received glycopyrrolate, 25 (38.5%) received atropine]. Mean age was 70.0 +/- 8.5 years (range, 48-86 years). Mean stenosis was 86.2 +/- 7.4% (range, 70-99%). No MI, major stroke, or death was observed in the 30-day postoperative period. Baseline systolic BP and HR were equivalent between groups. Postoperative bradycardia and hypotension were significantly lower in glycopyrrolate patients compared with atropine patients (30% vs 72%, P = .002; 2.5% vs 36%, P < .001, respectively). Postoperative hypertension was also significantly lower in the glycopyrrolate cohort (2.5% vs 16%, P = .047), whereas tachycardia, pressure changes, vasopressor use, and cardiac complications did not differ significantly. No significant differences in neurologic and access site complications were observed. CONCLUSIONS: Prophylactic glycopyrrolate, compared with atropine, reduces hemodynamic instability during CAS. The authors recommend glycopyrrolate use to prevent CAS-induced bradycardia and hypotension

OBJECTIVE: The utilization of endovascular abdominal aortic aneurysm repair (EVAR) in suitable patients has resulted in decreased perioperative morbidity and mortality. Octogenarians as a subgroup have been more readily offered EVAR, as it is less invasive, and therefore presumably better tolerated than conventional open aortic repair. The purpose of this study is to investigate periprocedural and late EVAR outcomes in octogenarians compared with patients less than 80 years of age. METHODS: From January 2003 to May 2008, 322 patients underwent EVAR. A total of 117 octogenarians were compared with 205 patients less than 80 years of age. A retrospective review of the demographic data, aneurysm details, perioperative morbidity, mortality, and late outcomes were analyzed. RESULTS: Octogenarians were significantly more likely to have a history of diabetes mellitus (51% vs 23%; P < .001), coronary artery disease (45% vs 32%; P = .0165), chronic obstructive pulmonary disease (44% vs 30%; P = .0113), and renal insufficiency (57% vs 31%; P < .0001). There were no significant differences in the rates of perioperative myocardial infarction, stroke, death, intestinal, or arterial ischemic complications between the two groups. Octogenarians had a significant higher rate of pulmonary complications (5.1% vs 1%; P < .03) and access-site hematomas (12% vs 2.4%; P = .001) than younger patients. When all significant perioperative morbidity was combined, octogenarians were twice as likely to develop complications following EVAR than younger patients (27.4% vs 11.7%; P = .001). At 5-year follow-up, younger patients were twice as likely to develop type II endoleaks. CONCLUSIONS: EVAR can be performed safely and effectively in octogenarians, and the incidence of major complications including myocardial infarction, stroke, and death is unchanged compared with younger patients. However, there is a significantly increased rate of access-site hematomas, pulmonary, and perioperative complications in octogenarians as a whole. Our findings suggest EVAR remains a suitable form of therapy in the elderly group provided there is an appropriate preoperative evaluation and perioperative monitoring following repair

BACKGROUND: Abdominal aortic aneurysm (AAA) disease is an insidious condition with an 85% chance of death after rupture. Ultrasound screening can reduce mortality, but its use is advocated only for a limited subset of the population at risk. METHODS: We used data from a retrospective cohort of 3.1 million patients who completed a medical and lifestyle questionnaire and were evaluated by ultrasound imaging for the presence of AAA by Life Line Screening in 2003 to 2008. Risk factors associated with AAA were identified using multivariable logistic regression analysis. RESULTS: We observed a positive association with increasing years of smoking and cigarettes smoked and a negative association with smoking cessation. Excess weight was associated with increased risk, whereas exercise and consumption of nuts, vegetables, and fruits were associated with reduced risk. Blacks, Hispanics, and Asians had lower risk of AAA than whites and Native Americans. Well-known risk factors were reaffirmed, including male gender, age, family history, and cardiovascular disease. A predictive scoring system was created that identifies aneurysms more efficiently than current criteria and includes women, nonsmokers, and individuals aged <65 years. Using this model on national statistics of risk factors prevalence, we estimated 1.1 million AAAs in the United States, of which 569,000 are among women, nonsmokers, and individuals aged <65 years. CONCLUSIONS: Smoking cessation and a healthy lifestyle are associated with lower risk of AAA. We estimated that about half of the patients with AAA disease are not eligible for screening under current guidelines. We have created a high-yield screening algorithm that expands the target population for screening by including at-risk individuals not identified with existing screening criteria.