Faculty Bibliography

PURPOSE: To retrospectively determine if arterial phase computed tomographic (CT) imaging is necessary for follow-up imaging of patients who have undergone endovascular stent-graft therapy for abdominal aortic aneurysm. MATERIALS AND METHODS: This HIPAA-compliant study was exempt from institutional review board approval; informed patient consent was waived. Eighty-five patients (66 men, 19 women; mean age, 66 years; range, 45-81 years) underwent 110 multidetector CT examinations after endovascular repair of abdominal aortic aneurysms. Nonenhanced CT images were obtained. Intravenous contrast material was then injected at 4 mL/sec, and arterial and venous phase (60 seconds) CT images were obtained. The nonenhanced and venous phase images were evaluated to determine if an endoleak was present. Subsequently, arterial phase images were analyzed. The effective dose was calculated. Ninety-five percent confidence intervals as indicators of how often arterial phase imaging would contribute to the diagnosis of endoleak were determined. RESULTS: Twenty-eight type II endoleaks were detected by using combined nonenhanced and venous phase acquisitions. Twenty-five of the 28 endoleaks were also visualized during the arterial phase. Three type II endoleaks were seen only during the venous phase. The arterial phase images depicted no additional endoleaks. Seventy-eight CT examinations performed in 67 patients revealed no endoleak during the venous phase. The arterial phase images also depicted no endoleaks at these examinations. Thus, for no more than 3.1% of all examinations, there was 95% confidence that arterial phase imaging would depict an endoleak missed at venous phase imaging. Arterial phase imaging contributed to a mean of 36.5% of the effective dose delivered. CONCLUSION: Study results indicate that arterial phase imaging may not be necessary for the routine detection of endoleaks. Radiation exposure can be decreased by eliminating this phase

Physicians in residency training will be the referring physicians of tomorrow. We sought to determine the current surgical and medical trainees' perception of vascular surgery's endovascular qualifications and capabilities. An anonymous survey was sent to all general surgery and internal medicine residents at a single academic institution. Respondents answered the question 'Which specialty is the most qualified to perform (1) inferior vena cava (IVC) filter insertion; (2) angiograms, angioplasty, and stenting of the carotid arteries; (3) renal arteries; (4) aorta; and (5) lower extremity arteries?' For each question, respondents chose one response, either vascular surgery, interventional radiology, interventional cardiology, or do not know. One hundred respondents completed the survey (general surgery, n=50; internal medicine, n=50). There was a significant difference in the attitudes of surgery and medicine residents when choosing the most qualified endovascular specialist (p<0.05). Surgery residents chose vascular surgery as the most qualified specialty for each listed procedure: carotid (80%, n=40), IVC (56%, n=28), aorta (100%, n=50), extremity (86%, n=43), renal (78%, n=39). Medicine residents chose vascular surgery as the most qualified specialty less frequently: carotid (66%, n=33), IVC (6%, n=3), aorta (88%, n=44), extremity (72%, n=36), renal (16%, n=8). There was no significant difference in specialty selection based on postgraduate year. There is a large discrepancy between surgical and medical trainees' perception of vascular surgery's endovascular abilities, particularly regarding IVC placement and renal artery interventions. If our own institution mirrors the nation, each passing year a significant portion of the 21,722 graduating internal medicine residents go into practice viewing vascular surgeons as second-tier endovascular providers. A concerted campaign should be undertaken to educate medical residents regarding the skills and capabilities of vascular surgeons

OBJECTIVES: Patients with diabetes mellitus have been shown to have an increased incidence of complications after elective major vascular surgery. The objective of this study was to evaluate a large series of diabetic patients undergoing carotid endarterectomy (CEA) to determine if outcome differed from nondiabetic patients and to examine predisposing factors of poor outcome among diabetic patients. METHODS: A retrospective review of a prospectively compiled database was performed. From 1992 through 2000, 2151 CEAs were performed at our institution. Of these, 507 were in diabetic patients (23.6%), and the remaining 1644 procedures were in nondiabetic patients (76.4%). RESULTS: Diabetic patients were significantly more likely than nondiabetic patients to have hypertension (70.8% vs 64.5%, P = .01) and cardiac disease (54.6% vs 49.1%, P = .03). They were more likely than nondiabetic patients to be symptomatic before surgery (52.5% vs 47.1%, P = .04) and to have sustained a preoperative stroke (21.3% vs 17.7%, P = .07). No differences were noted in other recorded demographic factors or in intraoperative factors between diabetic and nondiabetic patients. Despite these differences, diabetic patients had similar perioperative outcomes compared with nondiabetic patients, including perioperative myocardial infarction (0.6% vs 0.4%, P = NS), perioperative death (0.8% vs 0.5%, P = NS), and perioperative neurologic events such as transient ischemic attack and stroke (3.2% vs 2.4%, P = NS). Among diabetic patients alone, cigarette smoking, general anesthesia, the use of a shunt, and the lack of clamp tolerance while under regional anesthesia predicted adverse perioperative neurologic outcome, and contralateral occlusion was associated with increased perioperative mortality. CONCLUSIONS: Despite an increased prevalence of cardiac disease and preoperative neurologic symptoms among diabetic patients undergoing CEA, the rates of perioperative cardiac morbidity, mortality, and stroke were equal to nondiabetic patients. In contrast to nondiabetic patients, current cigarette smoking appeared to predict increased adverse neurologic outcomes among diabetic patients, and the presence of contralateral occlusion among diabetic patients appeared to predispose them towards increased perioperative mortality. The use of a general anesthetic appeared to increased perioperative neurologic risk among diabetic patients; however, this may be related to surgeon bias in the selection of anesthetic technique. Although diabetic patients may have an increase in complications after other major vascular surgical procedures, the presence of diabetes mellitus does not appear to significantly increase risk

Interval gangrene-necrosis of tissue proximal to a successful distal revascularization procedure-is an exceeding rare complication. To date, only nine cases have been reported in the literature, and all were secondary to traditional open bypass procedures. We report the first case, to our knowledge, of interval gangrene after endovascular stent placement in the superficial femoral artery. We believe that with the increasing utilization of endovascular techniques to treat limb ischemia, the serious complication of interval gangrene must be revisited. Assessment of collateral circulation, precise stent placement, and the appropriate choice of stents and stent grafts will become increasing important as more and more of these lesions are treated with endovascular techniques.

Endovascular intervention can provide an alternative method of treatment for visceral artery aneurysms. We conducted a retrospective review of all patients with visceral artery aneurysms at a single university medical center from 1990 to 2003, focusing on the outcome of endovascular therapy. Sixty-five patients with visceral artery aneurysms were identified: 39 splenic (SAA), 13 renal, seven celiac, three superior mesenteric (SMA), and three hepatic. Eleven patients (16.9%) had symptoms attributable to their aneurysms, which included a total of four ruptures (6.2%): three splenic and one hepatic. Management consisted of 18 (27.7%) endovascular interventions, nine (13.9%) open surgical repairs, and 38 (58.5%) observations. Mean aneurysm diameter for patients treated expectantly was significantly less than for those who underwent intervention (p = 0.001). Endovascular interventions included 15 (83.3%) embolizations (11 SAA, three renal, one hepatic) and three (16.7%) stent grafts (two SMA, one renal). The initial technical success rate of the endovascular procedures was 94.4% (17/18). However, there were four patients (22.2%) with major endovascular procedure-related complications: one late recurrence requiring open surgical repair, two large symptomatic splenic infarcts, and one episode of severe pancreatitis. These four patients had distal splenic artery aneurysms at or adjacent to the splenic hilum. There were no endovascular procedure-related deaths. Reasons for performing open surgical repair included three SAA ruptures diagnosed at laparotomy and complex anatomy not amenable to endovascular intervention (six patients). One surgical patient had a postoperative small bowel obstruction treated nonoperatively; and there was one perioperative death in a patient operated on emergently for rupture. Endovascular management of visceral artery aneurysms is a reasonable alternative to open surgical repair in carefully selected patients. Individual anatomic considerations play an important role in determining the best treatment strategy if intervention is warranted. However, four of 11 (36.4%) patients with distal splenic artery aneurysms treated with endovascular embolization developed major complications. Based on our experience, traditional surgical treatment of SAA with repair or ligation and concomitant splenectomy when necessary may be preferred in these cases

PURPOSE: To retrospectively determine whether differential temporal changes in signal intensity of the vertebral arteries, measured at a bolus-timing examination with a test dose of a gadolinium-based contrast agent, are present in patients with subclavian steal syndrome. MATERIALS AND METHODS: Institutional review board exemption was obtained, and informed consent was not required for this retrospective study. The study complied with the Health Insurance Portability and Accountability Act. Twenty-five patients with known or clinically suspected atherosclerotic disease of the aortic arch and branch vessels underwent breath-hold contrast material-enhanced magnetic resonance (MR) angiography with circulation time derived from a timing examination by using a test bolus of a gadolinium-based contrast agent. Eight patients (three men and five women aged 54-80 years; mean, 70 years) had subclavian stenosis or occlusion with retrograde vertebral artery flow confirmed with time-of-flight MR angiography, nine patients (eight men and one woman aged 31-91 years; mean, 70 years) had mild to severe ostial stenosis of a single vertebral artery, and eight patients (including four men and four women aged 53-86 years; mean, 73 years) had normal vertebral arteries. The difference in time to peak signal intensity between the right and left vertebral arteries was compared among the three groups by using Fisher exact and Cochran-Mantel-Haenszel tests. RESULTS: The delay in peak enhancement in the ipsilateral vertebral artery ranged from 2 to 4 seconds (mean, 2.5 seconds) in all eight patients with subclavian steal syndrome. In eight of nine patients with ostial vertebral artery stenosis and eight controls, both vertebral arteries filled simultaneously. The presence of unilateral delayed vertebral artery enhancement was significantly associated with retrograde flow in patients with subclavian steal syndrome, compared with patients with normal flow (P < .01) and those with ostial vertebral artery stenosis (P < .01). CONCLUSION: A bolus-timing examination performed with a test bolus of the gadolinium-based contrast agent via the neck vessels that demonstrates at least a 2-second delay in peak contrast enhancement in the right or left vertebral arteries may, in the appropriate clinical setting, indicate subclavian steal syndrome

PURPOSE: To retrospectively determine the natural history of type II endoleaks detected at thin-section multi-detector row computed tomographic (CT) angiography. MATERIALS AND METHODS: Neither institutional review board approval nor patient informed consent was required. Between December 1999 and December 2000, 83 patients (73 men and 10 women; mean age, 61 years; range, 55-75 years) underwent endovascular repair of an infrarenal abdominal aortic aneurysm with an endoluminal stent graft. Postprocedural abdominal CT angiography was performed every 3-12 months for the evaluation of endoleaks and the maximal sac diameter. A retrospective analysis of all postprocedural CT angiographic reports was performed until November 2003 to document the presence and development of type II endoleaks and the maximal orthogonal aneurysmal sac size. Findings at CT angiography were evaluated with regard to clinical outcomes and treatment in all patients in whom type II endoleaks were observed. The postprocedural follow-up period was 1.5-4.5 years (mean, 2.5 years). RESULTS: Twenty type II endoleaks were identified in 16 (19%) of the 83 patients. Four (20%) of the 20 endoleaks were embolized secondary to an increasing aneurysmal sac size when compared with that at preoperative CT angiography. These four leaks occurred in two patients, each with two separate endoleaks. Sixteen (80%) of the 20 endoleaks in 14 patients were managed with continued observation. In these patients, the aneurysmal sac size was stable or had decreased when compared with the size at preoperative CT angiography. Ten (62.5%) of the 16 endoleaks have sealed spontaneously during the follow-up, and six (37.5%) have persisted with stable or decreased aneurysmal sac size. None of the patients experienced aneurysmal sac rupture. CONCLUSION: Type II endoleaks with a stable or decreased aneurysmal sac size can be followed up with CT angiography secondary to the high rate of spontaneous resolution and a low risk of rupture

Although minimally invasive (MI) cardiac surgery reduces blood loss, hospital stay, and recovery time, some MI approaches require femoral arterial cannulation, which introduces a heretofore unknown risk of femoral arterial injury. This study was performed to examine the risk of femoral arterial injury after Port Access MI cardiac surgery (PA-MICS) with femoral cannulation. Data were prospectively obtained on 739 consecutive patients who had PA-MICS with femoral cannulation between June 1996 and April 2000, identifying any patient with new (<30 days postoperative) arterial insufficiency from the cannulation site. Patient characteristics (gender, age, height, weight, body surface area, smoking, peripheral vascular disease, diabetes) and operative variables (cannula size, cross-clamp time) were examined with univariate and multivariate analysis to identify risk factors for arterial injury. Injuries were defined and classified by radiologic and intraoperative assessment, and follow-up was obtained by patient examination and from the medical records. Femoral arterial occlusion (FAC) occurred in 0.68% (5/739) of patients (4 women, 1 man; age range 26-74 years). The risk of femoral injury was higher in women: 1.31% vs 0.23% (p = 0.07). One patient had intraoperative limb ischemia from iliofemoral dissection and was treated by axillopopliteal bypass. Four patients presented postoperatively with claudication. Three of these had iliofemoral arterial occlusion or localized iliofemoral dissection and were treated with iliofemoral bypass, and 1 patient had localized femoral artery stenosis treated by angioplasty. With a mean follow-up of 17.8 months (range 13-26 months) limb salvage was achieved in all patients. Secondary or tertiary interventions were required in 40% (2/5), both in patients with iliofemoral occlusion, and 1 patient (20% of femoral injuries, 0.135% of overall series) has chronic graft occlusion and long-term claudication. The risk of arterial injury after femoral arterial cannulation and perfusion for Port Access surgery was low (0.68%). This risk is increased in women and is unpredictable. Initial vascular repair has a significant failure rate, and secondary interventions are often necessary. Although the femoral cannulation and perfusion technique is safe overall, the risk must be clearly recognized

This is a retrospective review of all carotid endarterectomies (CEA) (n=91) done from 1993 to 2002 at an inner-city hospital (Group I). This group was compared to a randomly selected group of patients (n=445) treated at a private hospital (Group II). The same high-volume surgeons performed CEAs at both hospitals. The majority of Group I patients (71.4%) were members of racial minority groups. They were also more likely to be younger (p<0.001), hypertensive (p<0.03), diabetic (p<0.001), and current smokers (p<0.001); have contralateral carotid artery occlusion (p=0.04); and present with stroke (p<0.001) than Group II patients. Despite this, the incidence of postoperative myocardial infarction (2.2% vs 0.2%, p=0.08), stroke (1.1% vs 1.6%, NS), and death (1.1% vs 0%, NS) was comparable between the 2 groups. Aggressive preoperative workup for occult cardiac disease in Group I revealed an incidence of 25.9% (n=15). Of these, 5 (33.3%) were found to have coronary artery disease severe enough to warrant intervention before CEA. In an inner-city population with increased medical comorbidities, more severe cerebrovascular disease, and relatively low volume of carotid surgery, the results of CEA were comparable to those in patients treated at a high-volume private hospital. The presence of high-volume surgeons, operating at the low-volume municipal hospital, may contribute to the low complication rate. Finally, aggressive preoperative cardiac workup in this underserved population revealed a meaningful incidence of occult coronary artery disease requiring intervention before CEA