John W. Hallett

St. Francis School, Charleston, South Carolina, United States

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Publications (142)609.19 Total impact

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    ABSTRACT: Background: Providing patients and payers with publicly reported risk-adjusted quality metrics for the purpose of benchmarking physicians and institutions has become a national priority. Several prediction models have been developed to estimate outcomes after lower extremity revascularization for critical limb ischemia, but the optimal model to use in contemporary practice has not been defined. We sought to identify the highest-performing risk-adjustment model for amputation-free survival (AFS) at 1 year after lower extremity bypass (LEB). Methods: We used the national Society for Vascular Surgery Vascular Quality Initiative (VQI) database (2003-2012) to assess the performance of three previously validated risk-adjustment models for AFS. The Bypass versus Angioplasty in Severe Ischaemia of the Leg (BASIL), Finland National Vascular (FINNVASC) registry, and the modified Project of Ex-vivo vein graft Engineering via Transfection III (PREVENT III [mPIII]) risk scores were applied to the VQI cohort. A novel model for 1-year AFS was also derived using the VQI data set and externally validated using the PIII data set. The relative discrimination (Harrell c-index) and calibration (Hosmer-May goodness-of-fit test) of each model were compared. Results: Among 7754 patients in the VQI who underwent LEB for critical limb ischemia, the AFS was 74% at 1 year. Each of the previously published models for AFS demonstrated similar discriminative performance: c-indices for BASIL, FINNVASC, mPIII were 0.66, 0.60, and 0.64, respectively. The novel VQI-derived model had improved discriminative ability with a c-index of 0.71 and appropriate generalizability on external validation with a c-index of 0.68. The model was well calibrated in both the VQI and PIII data sets (goodness of fit P = not significant). Conclusions: Currently available prediction models for AFS after LEB perform modestly when applied to national contemporary VQI data. Moreover, the performance of each model was inferior to that of the novel VQI-derived model. Because the importance of risk-adjusted outcome reporting continues to increase, national registries such as VQI should begin using this novel model for benchmarking quality of care.
    No preview · Article · Oct 2015 · Journal of vascular surgery: official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter
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    ABSTRACT: Objective Carotid endarterectomy (CEA) for asymptomatic carotid artery stenosis is among the most common procedures performed in the United States. However, consensus is lacking regarding optimal preoperative imaging, carotid duplex ultrasound criteria, and ultimately, the threshold for surgery. We sought to characterize national variation in preoperative imaging, carotid duplex ultrasound criteria, and threshold for surgery for asymptomatic CEA. Methods The Society for Vascular Surgery Vascular Quality Initiative (VQI) database was used to identify all CEA procedures performed for asymptomatic carotid artery stenosis between 2003 and 2014. VQI currently captures 100% of CEA procedures performed at >300 centers by >2000 physicians nationwide. Three analyses were performed to quantify the variation in (1) preoperative imaging, (2) carotid duplex ultrasound criteria, and (3) threshold for surgery. Results Of 35,695 CEA procedures in 33,488 patients, the study cohort was limited to 19,610 CEA procedures (55%) performed for asymptomatic disease. The preoperative imaging modality used before CEA varied widely, with 57% of patients receiving a single preoperative imaging study (duplex ultrasound imaging, 46%; computed tomography angiography, 7.5%; magnetic resonance angiography, 2.0%; cerebral angiography, 1.3%) and 43% of patients receiving multiple preoperative imaging studies. Of the 16,452 asymptomatic patients (89%) who underwent preoperative duplex ultrasound imaging, there was significant variability between centers in the degree of stenosis (50%-69%, 70%-79%, 80%-99%) designated for a given peak systolic velocity, end diastolic velocity, and internal carotid artery-to-common carotid artery ratio. Although 68% of CEA procedures in asymptomatic patients were performed for an 80% to 99% stenosis, 26% were performed for a 70% to 79% stenosis, and 4.1% were performed for a 50% to 69% stenosis. At the surgeon level, the range in the percentage of CEA procedures performed for a <80% asymptomatic carotid artery stenosis is from 0% to 100%. Similarly, at the center level, institutions range in the percentage of CEA procedures performed for a <80% asymptomatic carotid artery stenosis from 0% to 100%. Conclusions Despite CEA being an extremely common procedure, there is widespread variation in the three primary determinants - preoperative imaging, carotid duplex ultrasound criteria, and threshold for surgery - of whether CEA is performed for asymptomatic carotid stenosis. Standardizing the approach to care for asymptomatic carotid artery stenosis will mitigate the significant downstream effects of this variation on health care costs.
    No preview · Article · Oct 2015
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    ABSTRACT: Objective: Medical management with antiplatelet (AP) and statin therapy is recommended for nearly all patients undergoing vascular surgery to reduce cardiovascular events. We assessed the association between preoperative use of AP and statin medications and postoperative in-hospital myocardial infarction (MI) in patients undergoing high-risk open surgery. Methods: We studied patients who underwent elective suprainguinal (n = 3039) and infrainguinal (n = 8323) bypass and open infrarenal abdominal aortic aneurysm repair (n = 3007) in the Vascular Quality Initiative (VQI, 2005-2014). We assessed the association between AP or statin use and in-hospital postoperative MI and MI/death. Multivariable logistic analyses were performed to identify the patient, procedure, and preoperative medication factors associated with postoperative MI and MI/death across procedures and patient cardiac risk strata. Secondary end points included bleeding, transfusion, and thrombotic complications. Results: Most patients were taking both AP and statin preoperatively (56% both agents vs 19% AP only, 13% statin only, and 12% neither agent). Use of both agents was more common for patients in the highest cardiac risk stratum (low, 54%; intermediate, 59%; high, 61%; P < .01). Increased cardiac risk was associated with higher MI rates (1.8% vs 3.8% vs 6.5% for low, intermediate, and high risk; P < .01). By univariate analysis, MI rate was paradoxically higher for patients taking both agents (3.7%, vs statin only 2.8%, AP only 2.6%, or neither AP nor statin 2.4%; P = .003). After multivariable adjustment, rates of MI in patients taking preoperative AP only (odds ratio [OR], 0.9; 95% confidence interval [CI], 0.7-1.2) and statin only (OR, 0.8; 95% CI, 0.6-1.2) were not different from those in patients taking either or neither medication (neither agent compared with taking both agents: OR, 1.0; 95% CI, 0.7-1.4; P > .05 for all). Similarly, rates of MI/death were not associated with medication status after multivariable adjustment. Estimated blood loss >1 liter (OR, 2.4; 95% CI, 1.6-3.7; P < .01) and transfusions of 1 or 2 units (OR, 2.5; 95% CI, 2.0-3.3; P < .01) and ≥3 units (OR, 4.0; 95% CI, 3.1-5.3; P < .01) were highly associated with MI, with similar findings related to composite MI/death in multivariable analysis. Rates of blood loss were slightly higher with AP use for all procedures; however, increased transfusions occurred only for infrainguinal bypass with AP use. Rates of reoperation for bleeding, graft thrombosis, or graft revision did not differ by preoperative AP use. Conclusions: Preoperative AP and statin medications as used in VQI were not associated with the rate of in-hospital MI/death after major open vascular operations. Rather, predicted cardiac risk and operative blood loss were significantly associated with in-hospital MI or MI/death. AP and statin medications appear to be more useful in reducing late mortality than early postoperative MI/death in VQI. However, they were not harmful, so their long-term benefit argues for continued use.
    No preview · Article · Sep 2015 · Journal of vascular surgery: official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter

  • No preview · Article · Dec 2014 · Journal of Vascular Surgery
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    ABSTRACT: The Society for Vascular Surgery Vascular Quality Initiative (SVS VQI) is designed to improve the quality, safety, effectiveness, and cost of vascular health care. The SVS VQI is uniquely organized as a distributed network of regional quality improvement groups across the United States. The regional approach allows for the involvement of a variety of health care professionals, the pooling of available resources and expertise, and serves as a motivating factor for each participating institution. Regional quality group sizes, administrative structure, and meeting logistics vary according to geography and regional needs. This review describes the process of forming, growing, and maintaining a regional quality improvement group of the SVS VQI.
    Preview · Article · Jan 2013 · Journal of vascular surgery: official publication, the Society for Vascular Surgery [and] International Society for Cardiovascular Surgery, North American Chapter

  • No preview · Article · Apr 2009 · Journal of Vascular Surgery
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    ABSTRACT: To determine carotid artery stenosis incidence after radiotherapy for head-and-neck neoplasms. This historical prospective cohort study comprised 44 head-and-neck cancer survivors who received unilateral neck radiotherapy between 1974 and 1999. They underwent bilateral carotid duplex ultrasonography to detect carotid artery stenosis. The incidence of significant carotid stenosis (8 of 44 [18%]) in the irradiated neck was higher than that in the contralateral unirradiated neck (3 of 44 [7%]), although this difference was not statistically significant (p = 0.13). The rate of significant carotid stenosis events increased as the time after radiotherapy increased. The risk of ipsilateral carotid artery stenosis was higher in patients who had undergone a neck dissection vs. those who had not. Patients with significant ipsilateral stenosis also tended to be older than those without significant stenosis. No other patient or treatment variables correlated with risk of carotid artery stenosis. For long-term survivors after neck dissection and irradiation, especially those who are symptomatic, ultrasonographic carotid artery screening should be considered.
    No preview · Article · Jan 2006 · International Journal of Radiation OncologyBiologyPhysics
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    ABSTRACT: To ascertain whether acute aortic dissection (AAD) remains the most common aortic catastrophe, as generally believed, and to detect any improvement in outcomes compared with previously reported population-based data. We determined the incidence, operative intervention rate, and long-term survival rate of Olmsted County, Minnesota, residents with a clinical diagnosis of AAD initially made between 1980 and 1994. The incidence of degenerative thoracic aortic aneurysm (TAA) rupture was also delineated. We compared these results with other population-based studies of AAD, degenerative TAA, and abdominal aortic aneurysm (AAA) rupture. During a 15-year period, we identified 177 patients with thoracic aortic disease. We focused on 39 patients with AAD (22% of the entire cohort) and 28 with TAA rupture (16%). The annual age- and sex-adjusted incidences were 3.5 per 100,000 persons (95% confidence interval, 2.4-4.6) for AAD and 3.5 per 100,000 persons (95% confidence interval, 2.2-4.9) for TAA rupture. Thirty-three dissections (85%) involved the ascending aorta, whereas 6 (15%) involved only the descending aorta. Nineteen patients (49%) underwent 22 operations for AAD, with a 30-day case fatality rate of 9%. Among all 39 patients with AAD, median survival was only 3 days. Overall 5-year survival for those with AAD improved to 32% compared with only 5% in this community between 1951 and 1980. In other studies, the annual incidences of TAA rupture and AAA rupture are estimated at approximately 3 and 9 per 100,000 persons, respectively. This study indicates that AAD and ruptured degenerative TAA occur with similar frequency but less commonly than ruptured AAA. Although timely recognition and management remain problematic, these new data suggest that recent diagnostic and operative advances are improving long-term survival in AAD.
    Full-text · Article · Mar 2004 · Mayo Clinic Proceedings
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    ABSTRACT: Popliteal artery entrapment syndrome is an uncommon entity with a spectrum of findings. Awareness of the imaging findings is important to tailor the examination for confirmation of the diagnosis and surgical planning. The diagnosis of popliteal artery entrapment syndrome requires not only depiction of the arterial changes but also identification of the abnormal anatomic structures responsible for the entrapment. Although arterial compression can be shown on conventional angiography or sonography, the underlying anatomic abnormality cannot be identified on either modality. Tailored MRI and MR angiography can show the abnormal muscular or fibrous attachment and the arterial findings necessary for diagnosis and surgical planning.
    No preview · Article · Dec 2003 · American Journal of Roentgenology
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    ABSTRACT: Decision-making in regard to elective repair of abdominal aortic aneurysms (AAA) requires careful assessment of factors that influence rupture risk, operative mortality, and life expectancy. Individualized consideration of these factors in each patient is essential, and the role of patient preference is of increasing importance. It is not possible or appropriate to recommend a single threshold diameter for intervention which can be generalized to all patients. Based upon the best available current evidence, 5.5 cm is the best threshold for repair in an "average" patient. However, subsets of younger, good-risk patients or aneurysms at higher rupture risk may be identified in whom repair at smaller sizes is justified. Conversely, delay in repair until larger diameter may be best for older, higher-risk patients, especially if endovascular repair is not possible. Intervention at diameter <5.5 cm appears indicated in women with AAA. If a patient has suitable anatomy, endovascular repair may be considered, and it is most advantageous for older, higher-risk patients or patients with a hostile abdomen or other technical factors that may complicate standard open repair. With endovascular repair, perioperative morbidity and recovery time are clearly reduced; however, there is a higher reintervention rate, increased surveillance burden, and a small but ongoing risk of AAA rupture. There is no justification at present for different indications for endovascular repair, such as earlier treatment of smaller AAA. Until long-term outcome of endoluminal repair is better defined and results of randomized trials available, the choice between endovascular and open repair will continue to rely heavily on patient preference.
    Preview · Article · Jun 2003 · Journal of Vascular Surgery
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    ABSTRACT: To assess the effect of demographic changes on rehabilitation of geriatric patients after amputation and the implications for future health resource allocation. Population-based study. Olmsted County, MN. Residents over the age of 65 years who had a major lower-extremity amputation because of peripheral arterial disease between 1956 and 1995. Patients who had amputations between 1956 and 1973 (earlier cohort) were compared with those who had amputations between 1974 and 1995 (later cohort). Not applicable. Demographic and clinical features, total number of amputations, amputation rates, and rate of successful prosthetic fitting over time. Of 292 patients, 93 had amputations between 1956 and 1973 and 199 between 1974 and 1995. Amputation rates declined after 1985, but the total number of amputations was unchanged. Patients in the later cohort were more likely to have a below-knee amputation (P<.001) and cerebrovascular disease (P=.008) and to be discharged to a nursing home (P<.001). There was no significant difference in median age at amputation, survival, or rates of successful prosthetic fitting over time. Although amputation rates have declined, the total number of amputations has increased. The rate of successful prosthetic fitting in the geriatric population has not changed significantly over 40 years. Amputations in the geriatric population in the United States will probably double from 28,000 to 58,000 per year by 2030, requiring considerable resources.
    No preview · Article · Oct 2002 · Archives of Physical Medicine and Rehabilitation
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    ABSTRACT: Although rare, splenic artery aneurysms (SAAs) have a definite risk of rupture. The optimal management of these aneurysms remains elusive. A retrospective chart review of all patients treated at our institutions with the diagnosis of SAA from January 1980 until December 1998 was undertaken. Follow-up was obtained via chart review and by direct phone contact of the patient or relative. No specific protocol was followed for management. From analysis of the patient data we concluded that although SAAs may rupture, not all intact aneurysms need intervention. Calcification does not appear to protect against rupture, although beta-blockade may be protective. Growth rates of SAA are slow and growth is infrequent. Selective management of SAAs is safe. Open ligation or transcatheter embolization should be considered for symptomatic aneurysms, for aneurysms > or = 2 cm in size, or for any SAA in women of childbearing years.
    No preview · Article · Jul 2002 · Annals of Vascular Surgery
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    ABSTRACT: The primary purpose of this study was to evaluate compliance, side effects, and safety associated with prolonged administration of doxycycline in patients with small asymptomatic abdominal aortic aneurysms (AAAs). A secondary goal was to determine how treatment with doxycycline influences circulating levels of matrix metalloproteinase-9 (MMP-9) in this patient population. Thirty-six patients with AAAs (30 men and 6 women; mean age, 69 +/- 1 years) were enrolled into a 6-month phase II study to evaluate treatment with doxycycline (100 mg orally twice a day). Aneurysm size was measured before and after treatment, and compliance and side effects were monitored. Plasma levels of doxycycline were measured midway through the study, and plasma MMP-9 concentrations were measured at baseline, 3 months, and 6 months. Thirty-three of the 36 patients (92%) completed 6 months of doxycycline treatment. Significant treatment-related side effects occurred in five patients (13.9%), including three with cutaneous photosensitivity reactions (8.3%), one with tooth discoloration (2.8%), and one with yeast infection (2.8%). A high rate of compliance with treatment was seen, despite minor but frequent side effects, including nonspecific gastrointestinal symptoms (25%), easily managed episodes of photosensitivity (22.2%), and reversible tooth discoloration (5.5%). The mean plasma doxycycline level after 3 months was 4.62 +/- 0.68 ug/mL (median, 3.64 microg/mL; range, 1.31 to 14.39 microg/mL; n = 23 patients). No significant change was seen in AAA diameter (42.7 +/- 1.3 mm at 6 months versus 41.0 +/- 0.9 mm at baseline), and the overall rate of AAA expansion was 0.63% +/- 0.25% per month. The mean plasma MMP-9 level (n = 19 patients) was elevated at baseline (118.9 +/- 37.9 ng/mL; upper limit of normal, 85 ng/mL) but subsequently decreased to 83.8 +/- 32.9 ng/mL at 3 months (not significant versus baseline) and to 66.4 +/- 24.2 ng/mL at 6 months (P =.022 versus baseline). Only 21% of patients had an elevated level of plasma MMP-9 after 6 months of treatment compared with 47% at baseline (P <.05). Prolonged administration of doxycycline is safe and well tolerated by patients with small asymptomatic AAAs and is associated with a gradual reduction in plasma MMP-9 levels. Further studies are needed to evaluate the long-term effects of doxycycline on the rate and extent of aneurysm growth and the potential use of plasma MMP-9 levels as a biomarker of aneurysm disease progression.
    Full-text · Article · Jul 2002 · Journal of Vascular Surgery
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    ABSTRACT: Aortic inflammation and the genes that regulate the immune response play an important role in abdominal aortic aneurysm pathogenesis. However, the modulating effects of such genetic and other environmental factors on the severity on aneurysm inflammation is not known. The objective of this study was to determine the influence of the human leukocyte antigen (HLA) class II genes, gender, and environmental factors on degree of abdominal aortic aneurysm tissue inflammation. Aneurysm specimens were obtained at the time of operation from 96 consecutive patients who underwent abdominal aortic aneurysm repair and were graded for degree of histologic inflammation. Multivariate analysis was used to determine the association of genetic and environmental factors with degree of inflammation and to determine the HLA-associated disease risk for aneurysm. Active cigarette smoking and female gender were independently associated with high-grade tissue inflammation identified histologically (odds ratio [OR], confidence interval [CI]: 5.6, 1.6 to 19.3; and 6.0, 1.4 to 26.2, respectively), and a specific HLA allele (DR B1(*)01) was inversely associated with inflammation (OR, CI: 0.2, 0.04 to 0.7). Overall, the HLA-DR B1(*)02 and B1(*)04 alleles were significantly associated with disease risk, more than doubling risk for abdominal aortic aneurysm (OR, CI: 2.5, 1.4 to 4.3; and 2.1, 1.2 to 3.7, respectively). Active cigarette smoking and female gender are significant disease-modulating factors associated with increased abdominal aortic aneurysm inflammation. In addition, the HLA class II immune response genes possess both disease modulating and disease risk properties, which may be useful in early aneurysm detection and surveillance.
    Full-text · Article · Jun 2002 · Journal of Vascular Surgery
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    ABSTRACT: Questions remain concerning the optimal site of graft origin and the extent of revascularization necessary to achieve excellent results for chronic mesenteric ischemia (CMI). Endovascular therapy also is performed for CMI. These factors prompted us to review our results to provide a current standard. Ninety-eight patients who underwent operation for CMI from 1989 to 1998 were reviewed. Patients with acute ischemia and arcuate ligament syndrome were excluded. Seventy-six women (78%) and 22 men (22%), with an average age of 66 years (range, 36 to 87 years), participated in the study. Abdominal pain was present in 95 patients (97%), and weight loss in 92 patients (94%). The superior mesenteric artery was severely diseased (70% to 99% stenosis or occlusion) in 90 patients (92%), the celiac artery in 81 patients (83%), and both arteries in 76 patients (78%). Bypass grafts were performed in 91 patients (93%), 77 antegrade and 14 retrograde. Of the other seven patients, five had endarterectomies, one reimplantation, and one patch angioplasty. Multivessel reconstruction was performed in 79 patients (81%), and single-vessel reconstruction in 19 (19%). Twelve patients had concomitant aortic reconstruction. Three early graft thromboses were seen. Five hospital deaths occurred (5.1%); one case had concomitant aortic reconstruction (1/12 versus 4/86; P = not significant). All five patients who died were older than 70 years (5/41 versus 0/57; P =.011). The median follow-up period was 1.9 years (range, 0 to 9.6 years). Follow-up was complete in all survivors. The 1-year, 5-year, and 8-year survival rates were 83%, 63%, and 55%, respectively. These rates were worse than the rates of the age-matched/gender-matched control subjects (P <.001). Survival was worse in patients greater than 70 years of age (P =.0013). Survival was unaffected by the number of vessels revascularized. The patients with retrograde grafts had decreased median survival rates (4.0 versus 5.7 years; P =.026), but they were older (75 versus 65 years; P =.0013). The 1-year and 5-year symptom-free survival rates were 95% and 92%, respectively. Symptoms recurred in six patients (6%): four had recurrent stenosis/occlusion and two had patent grafts. Symptom-free survival was unaffected by the number of vessels revascularized or by graft orientation. Operation for CMI was successful for most patients, with low operative mortality and excellent long-term relief of symptoms. Selective concomitant aortic procedures did not increase mortality rates. The rate of symptomatic recurrences was not different for single-vessel versus multiple-vessel reconstructions or for antegrade versus retrograde grafts. Patients older than 70 years had increased operative mortality and decreased survival rates. Endovascular therapy may be appropriate for this subset of patients.
    Preview · Article · May 2002 · Journal of Vascular Surgery
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    ABSTRACT: To determine the feasibility, safety, and clinical yield of angiographic screening among hypertensive patients undergoing coronary angiography. This study was a prospective cohort analysis of hypertensive patients who underwent cardiac catheterization at a tertiary care referral center from July 1998 to March 1999. Abdominal aortography was performed to screen for renal artery stenosis, the percentage of which was measured. The mean +/- SD age of the 297 study patients was 64.9+/-10.2 years; 58.6% were male, and 98.0% were white. Mean +/- SD systolic/diastolic blood pressure was 142.8+/-22.5/79.6+/-11.4 mm Hg. Aortography required a mean incremental dose of 62+/-9 mL of nonionic contrast agent. No complications were attributable to aortography. Of 680 renal arteries, 611 (90%) were visualized adequately. Also, 53% of patients had normal renal arteries, 28% had stenoses less than 50%, and 19.2% had stenoses of 50% or more. Renal artery stenosis was bilateral in 3.7% of patients and high grade (>70% stenosis) in 7%. Patients with renal artery stenosis were more likely to have had a previous coronary intervention. In multivariate analysis, systolic blood pressure (odds ratio [OR], 1.2; 95% confidence interval [CI], 1.03-138; P=.02), history of stroke or transient ischemic attack (OR, 2.7; 95% CI, 1.27-5.78; P=.01), and cancer (OR, 2.0; 95% CI, 1.02-3.82; P=.04) independently correlated with renal artery stenosis of 50% or more. The prevalence of incidental renal artery stenosis among hypertensive patients undergoing coronary catheterization is significant. Therefore, screening abdominal aortography should be considered in these patients to better define their risk of cardiovascular complications.
    Full-text · Article · Apr 2002 · Mayo Clinic Proceedings
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    ABSTRACT: Acute mesenteric ischemia (AMI) is a morbid condition with a difficult diagnosis and a high rate of complications, which is associated with a high mortality rate. For the evaluation of the results of current management and the examination of factors associated with survival, we reviewed our experience. The clinical data of all the patients who underwent operation for AMI between January 1, 1990, and December 31, 1999, were retrospectively reviewed, clinical outcome was recorded, and factors associated with survival rate were analyzed. Fifty-eight patients (22 men and 36 women; mean age, 67 years; age range, 35 to 96 years) underwent study. The cause of AMI was embolism in 16 patients (28%), thrombosis in 37 patients (64%), and nonocclusive mesenteric ischemia (NMI) in five patients (8.6%). Abdominal pain was the most frequent presenting symptom (95%). Twenty-five patients (43%) had previous symptoms of chronic mesenteric ischemia. All the patients underwent abdominal exploration, preceded with arteriography in 47 (81%) and with endovascular treatment in eight. Open mesenteric revascularization was performed in 43 patients (bypass grafting, n = 22; thromboembolectomy, n = 19; patch angioplasty, n = 11; endarterectomy, n = 5; reimplantation, n = 2). Thirty-one patients (53%) needed bowel resection at the first operation. Twenty-three patients underwent second-look procedures, 11 patients underwent bowel resections (repeat resection, n = 9), and three patients underwent exploration only. The 30-day mortality rate was 32%. The rate was 31% in patients with embolism, 32% in patients with thrombosis, and 80% in patients with NMI. Multiorgan failure (n = 18 patients) was the most frequent cause of death. The cumulative survival rates at 90 days, at 1 year, and at 3 years were 59%, 43%, and 32%, respectively, which was lower than the rate of a Midwestern white control population (P <.001). Six of the 16 late deaths (38%) occurred because of complications of mesenteric ischemia. Age less than 60 years (P <.003) and bowel resection (P =.03) were associated with improved survival rates. The contemporary management of AMI with revascularization with open surgical techniques, resection of nonviable bowel, and liberal use of second-look procedures results in the early survival of two thirds of the patients with embolism and thrombosis. Older patients, those who did not undergo bowel resection, and those with NMI have the highest mortality rates. The long-term survival rate remains dismal. Timely revascularization in patients who are symptomatic with chronic mesenteric ischemia should be considered to decrease the high mortality rate of AMI.
    Full-text · Article · Mar 2002 · Journal of Vascular Surgery
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    ABSTRACT: The objectives of this study were the comparison of patients who needed mesh closure of the abdomen with patients who underwent standard abdominal closure after ruptured abdominal aortic aneurysm repair and the determination of the impact of timing of mesh closure on multiple organ failure (MOF) and mortality. We performed a case-control study of patients who needed mesh-based abdominal closure (n = 45) as compared with patients who underwent primary closure (n = 90) after ruptured abdominal aortic aneurysm repair. Before surgery, the patients who needed mesh abdominal closure had more blood loss (8 g versus 12 g of hemoglobin; P <.05), had prolonged hypotension (18 minutes versus 3 minutes; P <.01), and more frequently needed cardiopulmonary resuscitation (31% versus 2%; P <.01) than did the patients who underwent primary closure. During surgery, the patients who needed mesh closure also had more severe acidosis (base deficit, 14 versus 7; P <.01), had profound hypothermia (32 degrees C versus 35 degrees C; P <.01), and needed more fluid resuscitation (4.0 L/h versus 2.7 L/h; P <.01). With this adverse clinical profile, the patients who needed mesh closure had a higher mortality rate than did the patients who underwent primary closure (56% versus 9%; P <.01). However, the patients who underwent mesh closure at the initial operation (n = 35) had lower MOF scores (P <.05), a lower mortality rate (51% versus 70%), and were less likely to die from MOF (11% versus 70%; P <.05) than the patients who underwent mesh closure after a second operation in the postoperative period for abdominal compartment syndrome (n = 10). This study reports the largest experience of mesh-based abdominal closure after ruptured abdominal aortic aneurysm repair and defines clinical predictors for patients who need to undergo this technique. Recognition of these predictors and initial use of mesh closure minimize abdominal compartment syndrome and reduce the rate of mortality as the result of MOF.
    Full-text · Article · Feb 2002 · Journal of Vascular Surgery
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    ABSTRACT: Objective: To determine the feasibility, safety, and clinical yield of angiographic screening among hypertensive patients undergoing coronary angiography. Patients and Methods: This study was a prospective cohort analysis of hypertensive patients who underwent cardiac catheterization at a tertiary care referral center from July 1998 to March 1999. Abdominal aortography was performed to screen for renal artery stenosis, the percentage of which was measured. Results: The mean ± SD age of the 297 study patients was 64.9±10.2 years; 58.6% were male, and 98.0% were white. Mean ± SD systolic/diastolic blood pressure was 142.8±22.5/79.6±11.4 mm Hg. Aortography required a mean incremental dose of 62±9 mL of nonionic contrast agent. No complications were attributable to aortography. Of 680 renal arteries, 611 (90%) were visualized adequately. Also, 53% of patients had normal renal arteries, 28% had stenoses less than 50%, and 19.2% had stenoses of 50% or more. Renal artery stenosis was bilateral in 3.7% of patients and high grade (>70% stenosis) in 7%. Patients with renal artery stenosis were more likely to have had a previous coronary intervention. In multivariate analysis, systolic blood pressure (odds ratio [OR], 1.2; 95% confidence interval [CI], 1.03-1.38; P=.02), history of stroke or transient ischemic attack (OR, 2.7; 95% CI, 1.27-5.78; P=.01), and cancer (OR, 2.0; 95% CI, 1.02-3.82; P=.04) independently correlated with renal artery stenosis of 50% or more. Conclusion: The prevalence of incidental renal artery stenosis among hypertensive patients undergoing coronary catheterization is significant. Therefore, screening abdominal aortography should be considered in these patients to better define their risk of cardiovascular complications.
    No preview · Article · Jan 2002
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    ABSTRACT: Infected aortic aneurysms are rare, difficult to treat, and associated with significant morbidity. The purpose of this study was to review the management and results of patients with infected aortic aneurysms and identify clinical variables associated with poor outcome. The clinical data and early and late outcomes of 43 patients treated for infected aortic aneurysms during a 25-year period (1976-2000) were reviewed. Variables were correlated with risk of aneurysm-related death and vascular complications, defined as organ or limb ischemia, graft infection or occlusion, and anastomotic or recurrent aneurysm. Infected aneurysms were infrarenal in only 40% of cases. Seventy percent of patients were immunocompromised hosts. Ninety-three percent had symptoms, and 53% had ruptured aneurysms. Surgical treatment was in situ aortic grafting (35) and extra-anatomic bypass (6). Operative mortality was 21% (9/42). Early vascular complications included ischemic colitis (3), anastomotic disruption (1), peripheral embolism (1), paraplegia (1), and monoparesis (1). Late vascular complications included graft infection (2), recurrent aneurysm (2), limb ischemia (1), and limb occlusion (1). Mean follow-up was 4.3 years. Cumulative survival rates at 1 year and 5 years were 82% and 50%, respectively, significantly lower than survival rates for the general population (96% and 81%) and for the noninfected aortic aneurysm cohort (91% and 69%) at same intervals. Rate of survival free of late graft-related complications was 90% at 1 year and 5 years, similar to that reported for patients who had repair of noninfected abdominal aortic aneurysms (97% and 92%). Variables associated with increased risk of aneurysm-related death included extensive periaortic infection, female sex, Staphylococcus aureus infection, aneurysm rupture, and suprarenal aneurysm location (P <.05). For risk of vascular complications, extensive periaortic infection, female sex, leukocytosis, and hemodynamic instability were positively associated (P <.05). Infected aortic aneurysms have an aggressive presentation and a complicated early outcome. However, late outcome is surprisingly favorable, with no aneurysm-related deaths and a low graft-related complication rate, similar to standard aneurysm repair. In situ aortic grafting is a safe and durable option in most patients.
    Preview · Article · Nov 2001 · Journal of Vascular Surgery

Publication Stats

8k Citations
609.19 Total Impact Points

Institutions

  • 2014
    • St. Francis School
      Charleston, South Carolina, United States
  • 1985-2006
    • Mayo Clinic - Rochester
      • • Department of Surgery
      • • Department of Cardiovascular Diseases
      Rochester, Minnesota, United States
  • 2002
    • Uniformed Services University of the Health Sciences
      • Department of Surgery
      Bethesda, MD, United States
  • 1993
    • Loma Linda University
      لوما ليندا، كاليفورنيا, California, United States
    • University of Minnesota Rochester
      Rochester, Minnesota, United States