Eugene M. Langan

Dobutamine stress echocardiography for cardiac risk assessment before aortic surgery

PURPOSE This study evaluates dobutamine stress echocardiography (DSE) for perioperative cardiac risk assessment with elective aortic surgery. METHODS Dobutamine stress echocardiography was used to evaluate 81 patients before infrarenal aortic surgery. Patients were placed into three groups. Group I (n = 31) had normal DSEs. Group II (n = 25) had resting wall motion abnormalities without dobutamine-induced changes of ischemia. Group III (n = 25) had evidence of dobutamine-induced ischemia. Patient analysis revealed that of 46 patients with clinical indicators of coronary artery disease (CAD), only 23 had DSEs with inducible ischemia. Two of 35 patients without clinical indicators of CAD had DSEs with inducible ischemia. RESULTS The 56 patients in group I and II underwent aortic reconstruction without cardiac complications or death. Of the 25 patients in group III, surgery was deferred in five (two patients with claudication and three with aneurysms < or = 5 cm), and four underwent coronary artery bypass grafting. Outcome after coronary artery bypass grafting included one death from stroke, one aneurysm rupture, and two uncomplicated aortic reconstructions. The remaining 16 patients in group III underwent aortic surgery, with three postoperative myocardial infarctions (MI) and no deaths. CONCLUSIONS Using DSE for preoperative assessment of cardiac risk allowed us to operate on 74 of 81 patients being considered for elective aortic reconstruction, with no operative deaths and a 4.1% rate of perioperative MI. Dobutamine stress echocardiography has the ability to identify patients with asymptomatic stress-induced ischemic myocardium and its increased risk for perioperative MI (p < 0.001). Equally important, for patients with clinical indicators of CAD but without DSE-inducible ischemia, no further cardiac evaluation is necessary.

Syndecan-4 Is a Primary-Response Gene Induced by Basic Fibroblast Growth Factor and Arterial Injury in Vascular Smooth Muscle Cells

Syndecans are a family of transmembrane proteoglycans that have been implicated in cell-extracellular matrix adhesion and growth factor binding. We reported previously that syndecan-1 expression by cultured rate vascular smooth muscle cells (VSMCs) is induced by serum- or platelet-derived growth factor (PDGF). We now report that syndecan-4 mRNA is rapidly induced in cultured VSMCs in response to basic fibroblast growth factor (bFGF) or serum stimulation. In the presence of cycloheximide, induction of syndecan-4 mRNA was enhanced. These characteristics identified syndecan-4 as a primary-response gene product in VSMCs. In contrast, syndecan-1 mRNA expression in response to serum was completely blocked in the presence of cycloheximide. We also examined the expression of syndecan mRNAs in VSMCs in response to balloon catheter injury in vivo. A reverse transcriptase-polymerase chain reaction technique was developed that enabled us to amplify all four syndecan mRNAs in a single reaction tube and determine relative changes in their expression. All four syndecan mRNAs were detected in uninjured rat carotid arteries. In endothelium-denuded arteries, the medial layer (presumably VSMCs) accounted for 70% to 90% of the syndecan mRNAs in the vessel wall. The levels of syndecan-2 and syndecan-3 mRNAs were not altered significantly after balloon injury. In contrast, syndecan-4 mRNA was increased at early times after injury but then decreased to control level by 7 days. Syndecan-1 mRNA levels showed a slower but prolonged increase that reached a maximum at 7 days after injury. Immunostaining with anti-syndecan-4 antibodies demonstrated a rapid increase in syndecan-4 proteoglycan expression in the injured carotid artery.

Prosthetic thigh arteriovenous access: outcome with SVS/AAVS reporting standards

PURPOSE Differences in the reporting methods of results for arteriovenous (AV) access can dramatically affect apparent outcome. To enable meaningful comparisons in the literature, the Society for Vascular Surgery and the American Association for Vascular Surgery (SVS/AAVS) recently published reporting standards for dialysis access. The purpose of the present study was to determine infection rates, patency rates, and possible predictive factors for prosthetic thigh AV access outcomes with the reporting standards of the SVS/AAVS. METHODS A retrospective analysis was performed of all patients who underwent placement of thigh AV access by the Surgical Teaching Service at Greenville Memorial Hospital between 1989 and 2001. Outcomes were determined based on SVS/AAVS Standards for Reports Dealing with AV Accesses. The rate of revision per year of access patency was also determined; this end point more accurately reflects the true cost and morbidity associated with AV access than do patency or infection rates alone. RESULTS One hundred twenty-five polytetrafluoroethylene thigh AV accesses were placed in 100 patients. Nine accesses were excluded from the study, six because there was no patient follow-up and 3 as a result of deaths unrelated to the access procedure and which occurred less than 30 days after access placement. There were six (4%) late access-related deaths. There were 18 (15%) early access failures, related to infection in 14 cases (12%), thrombosis in three cases (2%), and steal in one case (1%). Early failure was more common in patients with diabetes mellitus (P =.036). The primary and secondary functional patency rates were 19% and 54%, respectively, at 2 years. Infection occurred in 48 (41%) accesses. The patency and infection rates were not influenced by patient age, gender, body mass index, or diabetes mellitus. The median number of interventions per year of access patency was 1.68, and this outcome was positively correlated with body mass index (P <.001). CONCLUSIONS Prosthetic AV access in the thigh is associated with higher morbidity compared with that reported for the upper extremity, and should be considered only if no upper extremity AV access option is available. Early access failure and the requirement for an increased number of interventions to reestablish and maintain access patency are more common in patients with diabetes mellitus and obesity. The number of interventions per year of access patency is a valuable end point when assessing the outcome of AV access procedures.

Outcomes in the Management of Vascular Prosthetic Graft Infections Confined to the Groin: A Reappraisal

The management of vascular prosthetic graft infections confined to the groin continues to be controversial. To critically evaluate this problem, we reviewed the records of our vascular registry from December 1992 through February 1995 and found 17 incidences of groin sepsis involving a vascular prosthesis in 10 patients. These included a proximal prosthetic femoropopliteal bypass (n=6), an aortobifemoral graft limb (n=5), an ileofemoral bypass (n=3), a prosthetic femoral patch (n = 2), and an aortofemoral/femorofemoral bypass (n=1). The mean age of these patients was 65 years. Six patients were diabetic, four were on systemic steroids, and two were diabetic and on steroids. All infections were Szilagyi grade III including three in which the patients presented with local hemorrhage. Treatment consisted of irrigation, radical debridement with or without in situ graft replacement, and local rotational muscle flap coverage in nine cases, graft excision with extra-anatomic (obturator ileofemoral bypass) graft replacement in six cases, and excision alone in two cases. Of the 17 infections treated operatively and followed from 1 week to 18 months (median 5 months), eight (47%) showed no evidence of recurrence, six (35%) recurred, two (12%) caused early death, and one resulted in a thrombosed graft requiring extra-anatomic reconstruction. Of the nine infected grafts treated locally with muscle flaps, six showed recurrent infection from 3 weeks to 15 months and one thrombosed for a total local treatment failure rate of 78%. Only two grafts are free of infection at 4 and 5 months, respectively. Of the six incidences of infection treated with obturator bypass, four (66%) are free of infection and two resulted in patient death; both infections treated with excision alone were eradicated but resulted in a major lower extremity amputation. These data question the growing acceptance of debridement and local muscle flap coverage for the treatment of all prosthetic vascular graft infections confined to the groin, especially in patients who are diabetic or on systemic steroids.

Surgical implications of early failed endovascular intervention of the superficial femoral artery

BACKGROUND It is generally accepted that failed infrainguinal bypass with prosthetic material significantly compromises arterial run off, which may limit future revascularization. It is well known that the negative consequences of early vein graft thrombosis are limited, but the effect of failed peripheral angioplasty on the distal vasculature is poorly studied. The purpose of this study was to determine whether early failure after superficial femoral artery intervention influences subsequent revascularization options. METHODS Between July 1, 1998, and June 30, 2006, 276 patients underwent endovascular intervention of the superficial femoral artery. A prospective analysis of angiograms done before the intervention and after early failure (<or=200 days) was performed in a blinded fashion by three attending vascular surgeons to determine the optimal distal bypass site if an operation were to be performed. Inter-rater reliability of the angiogram scores was assessed using the Fleiss generalized kappa for multiple raters. Potential distal anastomotic sites were classified as above knee popliteal, below knee popliteal, tibial, or no adequate site. A consensus classification was determined for each patient (2 of 3 raters). RESULTS Of the 276 patients who underwent endovascular intervention of the superficial femoral artery, early failure was noted in 24 limbs in 23 patients. Angiographic records were available for 21 limbs in 20 patients (60% men; mean age, 65.3 +/- 11.3 years), of which 60% had critical limb ischemia, 40% had claudication, and 65% had diabetes. The distal bypass site was altered in six limbs (28.6%); four from popliteal to tibial and two from above knee to below knee popliteal. Inter-rater reliability was 0.54 (moderate/good). The procedures performed on these early failures were percutaneous transluminal angioplasty +/- stent (n = 14), infrainguinal bypass (n = 5), and no treatment (n = 1). Only 0.4% (1 of 276) of patients required major limb amputation due to early failure of a superficial femoral artery intervention. CONCLUSIONS Early failure after isolated endovascular intervention of the superficial femoral artery is infrequent and alters the distal target in 30% of early-failure patients if open bypass is planned. Salvage with repeat angioplasty, if necessary, can be accomplished in most patients, and the need for limb amputation is exceedingly rare. The early failure results in this study support a more liberal application of endovascular intervention to the superficial femoral artery in patients with lower extremity ischemia, especially claudication. The repercussions of late endovascular failure as well as the effects of disease progression need further study.

Can the Perclose suture-mediated closure system be used safely in patients undergoing diagnostic and therapeutic angiography to treat chronic lower extremity ischemia?

PURPOSE Mechanical closure devices for arterial hemostasis after angiography, such as the Perclose suture-mediated closure system, are designed to decrease time to ambulation and improve patient comfort. Although these devices are safe and efficacious, to date there has been little reported about use of the Perclose device in a cohort consisting exclusively of patients with lower extremity peripheral vascular disease. The purpose of this study was to determine the safety and efficacy of routine use of the Perclose system in patients with documented peripheral vascular disease undergoing angiography to treat chronic lower extremity ischemia. METHODS The Perclose device was placed for arterial closure after femoral artery access in 500 consecutive patients with documented peripheral vascular disease (ankle-brachial index, <0.8) who underwent diagnostic angiography or percutaneous intervention because of chronic lower extremity ischemia. These 500 patients composed 91% of all patients who underwent angiography because of chronic lower extremity ischemia between January 1, 2001, and April 1, 2002. All complications associated with the Perclose device were identified and reviewed. RESULTS Of the 500 arteries, 54% were accessed for diagnostic angiography and 46% for intervention. Perclose device placement was successful in 475 attempts (95%). Overall major complication rate was 1.4% (7 of 500 arteries). Complications included one death from retroperitoneal hemorrhage; three episodes of limb ischemia, two requiring operation and one requiring lytic therapy; two pseudoaneurysms; and one hematoma, which prolonged hospitalization. The hematoma was the only complication in the 25 patients with failed Perclose device placement. There were no infections requiring admission or operation. CONCLUSION The Perclose suture-mediated closure device is efficacious and can be used safely in selected patients with documented peripheral vascular disease. Complications associated with this device tend to be more severe than those historically reported for manual compression. Substantial experience with use of this device is required to achieve excellent results in patients with difficult anatomy.

The LEGS Score: A Proposed Grading System to Direct Treatment of Chronic Lower Extremity Ischemia

ObjectiveTo prospectively compare the Lower Extremity Grading System (LEGS)-derived “recommended treatment” to the actual treatment performed and to analyze LEGS intergrader scoring consistency by comparing blinded scoring results between physician graders. Summary Background DataDue to technical advances and the increased medical complexity of the aging population, the most appropriate treatment for chronic lower extremity ischemia—open surgery versus endovascular—is again in flux. In an attempt to standardize management, the LEGS score, based on the best available outcomes data, was devised by the physicians of an established vascular service. MethodsFrom March to June 2002, all chronically ischemic lower extremities that met standard indications for revascularization were prospectively enrolled and independently graded with the LEGS score by an “endovascular surgeon” and an “open surgeon” for comparative analysis. The results were then blindly evaluated to determine whether the LEGS-derived “recommended treatment” agreed with the actual treatment rendered and to assess for intergrader consistency. Agreement was assessed using kappa statistical analysis. ResultsOf the 137 presenting limbs (mean patient age 66.4 yo; 43% claudication, 57% limb-threatening ischemia), 107 were treated (65% endovascular, 30% open surgery, 5% amputation), 16 were pending treatment, and 14 were not treated because of patient refusal (n = 13) or death (n = 1). The LEGS score predicted the actual or offered clinical treatment in 90% of cases. The LEGS score comparison between physician graders resulted in identical “recommended treatment” in 116 of 128 cases for a 90.6% agreement. ConclusionsA reproducible scoring system to guide the treatment of patients with chronic lower extremity ischemia is possible. While systems like the LEGS score may have potential clinical application, their use as a treatment standardization tool for future prospective outcomes comparisons between open and endovascular surgery will be essential.

Do Current Outcomes Justify More Liberal Use of Revascularization for Vasculogenic Claudication? A Single Center Experience of 1,000 Consecutively Treated Limbs

BACKGROUND The purpose of this study was to reconsider current recommended treatment guidelines for vasculogenic claudication by examining the contemporary results of surgical intervention. STUDY DESIGN We performed a retrospective review of 1,000 consecutive limbs in 669 patients treated for medically refractory vasculogenic claudication and prospectively followed. Outcomes measured included procedural complication rates, reconstruction patency, limb salvage, maintenance of ambulatory status, maintenance of independent living status, survival, symptom resolution, and symptom recurrence. RESULTS Of the 1,000 limbs treated, endovascular therapy was used in 64.3% and open surgery in 35.7% of patients; aortoiliac occlusive disease was treated in 70.1% and infrainguinal disease in 29.9% of patients. The overall 30-day periprocedural complication rate was 7.5%, with no notable difference in complication rates when comparing types of treatment or levels of disease. Overall reconstruction primary patency rates were 87.7% and 70.8%; secondary patencies were 97.8% and 93.9%; limb salvage, 100% and 98.8%; and survivals, 95.4% and 76.9%, at 1 and 5 years, respectively. More than 96% of patients maintained independence and ambulatory ability at 5 years. Overall symptom resolution occurred in 78.8%, and symptom recurrence occurred in 18.1% of limbs treated, with slightly higher resolution and recurrence noted in patients treated with endovascular therapy. CONCLUSIONS Contemporary treatment of vasculogenic claudication is safe, effective, and predominantly endovascular. These data support a more liberal use of revascularization for patients with claudication and suggest that current nonoperative treatment guidelines may be based more on surgical dogma than on achievable outcomes.

Contemporary Management of Diabetic Neuropathic Foot Ulceration: A Study of 917 Consecutively Treated Limbs

BACKGROUND For patients with diabetic neuropathic foot ulceration, the current treatment paradigm is heavily weighted toward limb revascularization; aligning incentives to perform more surgery and less ulcer management/prevention. Our purpose was to perform an analysis of functional outcomes to assess this current treatment paradigm. STUDY DESIGN Nine hundred and seventeen neuropathic ulcerated feet in 706 patients with diabetes were analyzed. Four hundred and sixty limbs (50.2%) had concomitant ischemia, 219 of which were revascularized (137 angioplasty and 82 open surgery). Outcomes measured included ulcer healing, survival, limb salvage, amputation-free survival, maintenance of ambulation, and independence. Independent predictors of outcomes were measured using an Extended Cox Model. RESULTS Overall outcomes (n = 917) were: ulcer healed, n = 250 (27%; mean time to healing 33 weeks); functionally healed, n = 488 (53%; mean time to functional healing 29 weeks); 5-year limb salvage, 68%; survival, 38%; amputation-free survival, 30%; maintenance of ambulation, 64%; and maintenance of independence, 74%. There was little difference in ulcer healing rates for patients with or without ischemia (28.5% versus 26%; p = 0.4). However, ischemia was a significant marker of poor outcomes (nonischemic ulcer, ischemic ulcer revascularized, and ischemic ulcer not revascularized: 5-year limb salvage of 80%, 61%, and 51%; p < 0.001); survival (47%, 37%, and 24%; p = 0.03); amputation-free survival (37%, 28%, and 17%; p < 0.001); maintenance of ambulation (74%, 55%, and 55%; p < 0.001); and maintenance of independence (82%, 72%, and 58%; p = 0.01). Wound healing was an independent predictor of survival and amputation-free survival (survival: hazard ratio = 0.58; 95% CI,0.46-0.73; amputation-free survival: hazard ratio = 0.42; 95% CI, 0.33-0.53). CONCLUSIONS The current treatment paradigm is associated with relatively poor healing rates and substantial late morbidity and mortality. Although revascularization is effective treatment for ischemia, it is probably overvalued when compared with the potential improvement afforded by better medical foot wound management.

An analysis of limb-threatening lower extremity wound complications after 1090 consecutive coronary artery bypass procedures

The objective of this study was to examine and characterize limb-threatening lower extremity wound or soft tissue complications after coronary artery bypass (CABG) and determine risk factors for their cause. While minor wound problems of the leg after CABG are not uncommon, serious limb-threatening complications, though less frequent, do occur and are often de-emphasized in the surgical literature. A review of 1090 consecutive CABG procedures performed from January 1, 1995 through December 31, 1995 was instituted, which screened for limb-threatening lower extremity wound or soft tissue complications defined as wounds that: required additional surgery for treatment; prolonged the length of stay; or which required lengthy home health nursing for treatment. Minor lymph leaks, leg swelling, infections or wound problems treated as an outpatient were excluded. Of 1090 patients, 54 (5.0%) experienced a limb-threatening lower extremity complication. Complications were categorized as vein harvest incision non-healing (n = 36, 66.7%), decubitus ulceration (n = 11, 20.4%), forefoot ischemia/embolization (n = 10, 18.5%), groin hematoma/abscess (n = 6, 11.1%), severe cellulitis (n = 3, 5.6%), or a combination (n = 12, 22.2%). Statistically significant risk factors by univariate and bivariate analysis for a complication included older age (68 years vs 62 years, p = 0.007), female sex (57% vs 28%, p, 0.001), diabetes (57% vs 33%, p = 0.005) and longer pump time (129 min vs 114 min, p = 0.009). These complications necessitated five major lower extremity amputations and nine revascularization procedures. Chronic lower extremity ischemia from peripheral vascular disease (PVD) was a major contributing factor for the development of wounds in at least 23 (42.6%) of these patients, though suspected in only 10 (43.5%) preoperatively. A non-healing vein harvest incision below the knee of a patient retrospectively found to have inadequate distal circulation for healing occurred in 17 (31.5%) of the total 54 cases. It was concluded that non-healing vein incisions, decubitus ulcers and forefoot ischemic lesions frequently occurring in older diabetic females with undetected pre-existing PVD, comprise the majority of limb-threatening leg complications after CABG. Nearly one-third of the complications may have been avoided had the vein harvest incision not been made at the ankle of a patient with unappreciated PVD.