Impact of diabetes mellitus on infrainguinal bypass grafting

Indications for a "Surgery-First" Approach for the Treatment of Lower Extremity Arterial Disease

BACKGROUND

In recent years, there has been a tendency toward an "endovascular-first" approach for the treatment for femoropopliteal arterial disease. The purpose of this study is to determine if there are patients that are better served with an initial femoropopliteal bypass (FPB) rather than an endovascular attempt at revascularization.

METHODS

A retrospective analysis of all patients undergoing FPB between June 2006 - December 2014 was performed. Our primary endpoint was primary graft patency, defined as patent using ultrasound or angiography without secondary intervention. Patients with <1-year follow-up were excluded. Univariate analysis of factors significant for 5-year patency was performed using χ2 tests for binary variables. A binary logistic regression analysis incorporating all factors identified as significant by univariate analysis was used to identify independent risk factors for 5-year patency. Event-free graft survival was evaluated using Kaplan-Meier models.

RESULTS

We identified 241 patients undergoing FPB on 272 limbs. FPB indication was disabling claudication in 95 limbs, chronic limb-threatening ischemia (CLTI) in 148, and popliteal aneurysm in 29. In total, 134 FPB were saphenous vein grafts (SVG), 126 were prosthetic grafts, 8 were arm vein grafts, and 4 were cadaveric/xenografts. There were 97 bypasses with primary patency at 5 or more years of follow-up. Grafts patent at 5 years by Kaplan-Meier analysis were more likely to have been performed for claudication or popliteal aneurysm (63% 5-year patency) as compared with CLTI (38%, P < 0.001). Statistically significant predictors (using log rank test) of patency over time were use of SVG (P = 0.015), surgical indication of claudication or popliteal aneurysm (P < 0.001), Caucasian race (P = 0.019) and no history of COPD (P = 0.026). Multivariable regression analysis confirmed these 4 factors as significant independent predictors of 5-year patency. Of note, there was no statistical correlation between FPB configuration (above or below knee anastomosis, in-situ versus reversed saphenous vein) and 5-year patency. There were 40 FPBs in Caucasian patients without a history of COPD receiving SVG for claudication or popliteal aneurysm that had a 92% estimated 5-year patency by Kaplan-Meier survival analysis.

CONCLUSIONS

Long-term primary patency that was substantial enough to consider open surgery as a first intervention was demonstrated in Caucasian patients without COPD, having good quality saphenous vein, and who underwent FPB for claudication or popliteal artery aneurysm.

Racial/Ethnic Disparities in Amputation and Revascularization

This study investigates whether ethnic minorities presenting with critical limb ischemia (CLI) are more likely to undergo major limb amputation compared to white patients. The Nationwide Inpatient Sample (NIS) database was used to identify all patients admitted with CLI; lower extremity revascularization; and major lower extremity amputation from 1998 to 2005. The NIS identified 240 139 patients presenting with CLI—68.2% white, 19.5% black, 9.0% Hispanic, and 1.24% Asian. In all, 83 328 patients underwent revascularization—73.7% white, 15.9% black, 7.4% Hispanic, and 1.1% Asian. The majority of the interventions were open. In all, 111 548 patients underwent a major lower extremity amputation—61% white, 25.4% black, 10.1% Hispanic, and 1.1% Asian. The mean Charlson comorbidity scores for amputation were 2.1 for whites, 2.0 for blacks, 2.3 for Hispanics, and 2.5 for Asians (for all data, P < .05).Blacks make up a disproportionately higher proportion of patients admitted for CLI and undergoing amputation, with a lower proportion undergoing revascularization.

The role of established and emerging risk factors in peripheral vascular graft occlusion

Several studies have evaluated the association between established as well as emerging vascular risk factors with peripheral graft occlusion. There is evidence for a link between the risk for graft occlusion and total serum cholesterol, low-density lipoprotein cholesterol and triglyceride levels. The overall effect of smoking shows a 2.35-fold increase in risk of graft failure. Studies involving diabetic patients undergoing peripheral bypass may have failed to detect higher occlusion rates, possibly due to increased morbidity and mortality as well as higher amputation rates even if the graft is patent. Both antiplatelet agents and anticoagulation seem to be effective in the prevention of graft occlusion. Unconvincing data have been published with regards to the effect of hypertension on graft patency. Emerging factors such as fibrinogen, lipoprotein (a), C-reactive protein and homocysteine levels should also be considered when assessing the risk of graft occlusion. More research is needed to prevent graft occlusion due to the obvious clinical relevance, quality of life and cost issues.

Revascularization for peripheral vascular disease in Aboriginal and non-Aboriginal patients

BACKGROUND

Canadian Aboriginal subjects have a higher prevalence of diabetes, renal disease, and lower extremity amputation than non-Aboriginal subjects. However, limited information is available about patient outcomes for arterial bypass surgery in Canadian Aboriginal compared with non-Aboriginal subjects.

METHODS

A retrospective study of all patients undergoing revascularization for peripheral vascular disease at a tertiary care referral center was performed.

RESULTS

A total of 828 procedures were performed on 678 patients between 1995 and 2002: 108 (13%) procedures on 84 (12%) Aboriginal patients and 720 (87%) procedures on 594 (88%) non-Aboriginal patients. Aboriginal patients had a higher prevalence of diabetes, chronic renal failure, and end-stage renal disease than non-Aboriginal patients. Aboriginal patients presented with more serious complications (gangrene [Aboriginal, 63 [58%] of 108 patients; non-Aboriginal, 112 [16%] of 720 patients; P < .0001] and nonhealing ulcer [Aboriginal, 29 [27%] of 108 patients; non-Aboriginal, 131 [18%] of 720 patients; P < .05]) and required urgent or emergency revascularization (Aboriginal, 47 [49%] of 95 patients; non-Aboriginal, 228 [36%] of 634 patients; P < .02) more frequently than non-Aboriginal patients. The 60-month patient mortality was similar for both groups (Aboriginal, 20 [24%] of 84 patients; non-Aboriginal, 160 [27%] of 594 patients; not significant), but Aboriginal patients had loss of limb more frequently (Aboriginal, 19 [18%] of 108 patients; non-Aboriginal, 62 [9%] of 720 patients; P < .0001) and had loss of primary graft patency more frequently (Aboriginal, 39 [36%] of 108 patients; non-Aboriginal, 155 [22%] of 720 patients; P < .0001) than non-Aboriginal patients.

CONCLUSIONS

Canadian Aboriginal subjects had worse outcomes with revascularization than non-Aboriginal subjects, but ethnicity and diabetes were not independent risk factors for poor outcome. Multivariate analysis showed that the poor outcomes in mortality, limb salvage, and primary graft patency among Aboriginal patients undergoing revascularization may be attributed to renal disease and a more advanced mode of presentation of peripheral vascular disease complications at the time of intervention.

Review of prevalence and outcome of vascular disease in patients with diabetes mellitus

OBJECTIVES

Review the literature to determine the prevalence and outcome in patients with diabetes that undergo surgery to correct carotid artery stenosis, lower extremity arterial disease, and abdominal aortic aneurysm (AAA).

DESIGN AND MATERIALS

Studies were obtained from searches over the past 15 years on the National Library of Medicine's online search engine.

RESULTS

The review demonstrated an equivalent prevalence of carotid artery stenosis requiring surgery in patients with diabetes, it favored no increase risk of post-CEA stroke, and it was split on perioperative morbidity and mortality risk. There was an increase prevalence of lower extremity arterial disease requiring surgery in patients with diabetes, it favored equivalent patency and limb salvage rates, and it was split on the morbidity and mortality risk. The review demonstrated a decrease in AAA prevalence among patients with diabetes, it found an increase in the morbidity risk, and equivalent mortality risk.

CONCLUSIONS

Stroke, graft patency, and limb salvage rates in patients with diabetes after surgery are similar to patients without diabetes; however, their risk of complications is increased after surgery and the mortality risk may be higher after CEA.

Prospective randomized study on reversed saphenous vein infrapopliteal bypass to treat limb-threatening ischemia: common femoral artery versus superficial femoral or popliteal and tibial arteries as inflow

PURPOSE

Use of inflow sources distal to the common femoral artery (CFA) for bypass to infrapopliteal arteries is a compromise measure when the length of the vein is not adequate. The purpose of this study was to compare the clinical outcome of vein infrapopliteal bypass arising from the CFA and from the distal superficial femoral or popliteal and tibial arteries in patients with limb-threatening ischemia.

METHODS

Over 13 years, 160 vein infrapopliteal vein bypass procedures (160 patients) were randomized into 2 groups, 80 with inflow arising from the CFA (group 1) and 80 with inflow from below the CFA (group 2). Patency and limb salvage rates were assessed with the Kaplan-Meier method. All patients underwent graft surveillance at discharge and at 30 days and 6 months after surgery, then every 6 months thereafter. Follow-up ranged from 30 days to 127 months (mean, 49 months).

RESULTS

Groups were similar with regard to age, sex, and most atherosclerotic risk factors. Gangrene as an indication for surgery was statistically more frequent in group 1 (73.7% vs 48.7%; P = .002), whereas nonhealing ulcer and rest pain were statistically more frequent in group 2 (respectively, 51.2% vs 25%; P = .001 and 46.2% vs 28.7%; P = .03). No patients died during the perioperative (30 days) period. At 1, 3, and 5 years patency and limb salvage rates were comparable between groups, tending toward significance for the 5-year primary patency rate (73% vs 57%; P = .08).

CONCLUSIONS

In the absence of significant proximal disease, infrapopliteal revascularization arising distal to the CFA can ensure patency and limb salvage rates statistically similar to those with use of the CFA. Moreover, procedures arising distal to the CFA required fewer graft revisions to maintain patency of failing grafts.

Diabetes and the outcome of infrainguinal bypass for critical limb ischaemia

AIM

To examine the influence of diabetes mellitus (DM) on the outcome of infrainguinal bypass operations performed for critical foot ischaemia in Chinese patients.

METHODS

A prospective audit of 265 consecutive infrainguinal bypass operations.

RESULTS

Diabetic patients suffered more frequently from ischaemic heart disease (48% vs 25%, P=0.001) and tissue loss (90% vs 79%, P=0.01) at presentation. Cigarette smoking was more prevalent in the non-diabetic (NDM) group (72% vs 51%, P=0.001). Arterial segments distal to the common femoral artery were more often used as inflow to bypass graft in DM patients (36% vs 22%, P=0.02). Operative mortality (seven DM vs one NDM, P=0.19). Early graft failure (7% in DM group vs 10% in NDM group, P=0.24), wound infection rate (24% in DM group vs 17% in NDM group, P=0.21), early limb loss (9% in DM group vs 6% in NDM group, P=0.66) were comparable. However, hospital mortality was higher in DM patients (8% vs 1%, P=0.04). DM patients more frequently required further surgical debridement postoperatively (20% vs 9%, P=0.04). Long-term, patient survival was inferior in the DM group (43% NDM vs 33% DM at 5 years, P=0.03). Primary graft patency (46% DM vs 34% NDM at 4 years P=0.19), secondary graft patency (57% DM vs 47% NDM at 4 years P=0.14) and limb salvage rate (78% vs 81% at 5 years, P=0.79) were comparable.

CONCLUSION

Diabetes mellitus adversely affects hospital mortality and long-term survival. Graft patency and limb salvage are not compromised by the presence of DM.

Graft patency and clinical outcome of femorodistal arterial reconstruction in diabetic and non-diabetic patients: results of a multicentre comparative analysis

OBJECTIVE

in diabetic patients with critical limb ischaemia (CLI) an inferior success rate following infrainguinal bypass surgery is quite often suggested. The aim of this retrospective analysis was, therefore, to evaluate the graft patency and, particularly, the clinical outcome at 1 year in diabetic compared with non-diabetic patients.

MATERIAL AND METHODS

two hundred and eleven patients (diabetics 94; non-diabetics 117) with femorodistal reconstruction for CLI were studied. Groups were comparable with regard to the Fontaine classification, the distribution of vascular risk factors, graft material, distal anastomosis site, and the angiographic runoff grading.

RESULTS

diabetes did not adversely affect graft function. For diabetics and non-diabetics primary cumulative patency rate at 1 year was found to be 66 and 56%, respectively (p=0.10) and a virtually identical limb salvage rate of 85 and 83% was achieved (p=0.76). With regard to healing of ischaemic foot ulcers a trend against diabetics was noted with a healing rate of 81% compared to 96% in non-diabetics at 1 year (p=0.067); gangrenous foot lesions could be equally remedied in 94% and in 87% among patients with and without diabetes (p=0.44). The survival rate of diabetics, however, was significantly lower with 78% at 1 year compared with 95% in non-diabetic patients (p=0.0004).

CONCLUSIONS

our preliminary results support the view that infrainguinal bypass grafting can be safely done even in diabetics. Despite increased mortality in this group, liberal indication for reconstructive vascular surgery seems to be justified by favourable patency rates and clinical outcome in selected patients.