Lower extremity minor amputations: the roles of diabetes mellitus and timing of revascularization.

INTRODUCTION: Despite the frequent performance of minor foot amputations in patients with lower extremity vascular disease, little is known regarding the rate of conversion to major amputations and the role of bypass graft timing in relation to amputation. METHODS: Between January 1990 and December 2001, 670 patients underwent 920 minor amputations (interphalangeal, ray, or transmetatarsal) on 747 limbs. RESULTS: Of 670 patients, 468 were men (69.9%), 616 had diabetes mellitus (91.9%), and 137 (19.7%) had a serum creatinine level >2.0 mg/dL, of whom 92 were on dialysis (end-stage renal disease) (11.5%). Ipsilateral revascularization was performed < or =30 days before the initial amputation in 64.9% (485 of 747), whereas 9.8% (73 of 747) had a bypass < or =30 days postamputation. The initial amputation levels were 466 interphalangeal (62.4%), 159 transmetatarsal (21.3%), and 122 ray (16.3%). Operative 30-day mortality was 0.7% (6 of 920). Limb salvage was 89.8% at 1 year and 82.3% at 5 years. Diabetes mellitus had no impact on limb salvage (P = .61). Limb loss predictors included end-stage renal disease (odds ratio [OR], 1.72, 95% confidence interval [CI], 1.12 to 2.83, P < .01) and the need for transmetatarsal amputation as the initial procedure (OR, 1.62; 95% CI, 1.15 to 1.93; P < .01). Patients with revascularizations subsequent to an initial amputation had a significant increase in limb loss (OR, 2.11; 95% CI, 1.39 to 4.21, P < .005). Patient survival was 83.9% at 1 year and 43.5% at 5 years. Neither gender nor diabetes mellitus impacted survival; however, serum creatinine levels >2.0 mg/dL (5 years, 48.8% +/- 2.3% vs 23.9% +/- 4.2%, P < .0001) and the need for a major amputation < or =30 days (3 years, 60.8% +/- 2.1% vs 40.1% +/- 7.8%, P < .01) adversely affected survival. CONCLUSIONS: Although minor amputations can lead to limb preservation in most patients, the performance of a revascularization subsequent to amputation, transmetatarsal as the initial amputation, and end-stage renal disease are poor prognostic indicators. Inferior long-term patient survival is most closely associated with renal insufficiency and conversion to major amputation early after the initial procedure.

Preoperative cardiac evaluation does not improve or predict perioperative or late survival in asymptomatic diabetic patients undergoing elective infrainguinal arterial reconstruction.

OBJECTIVE: Patients undergoing infrainguinal arterial reconstruction frequently have increased cardiac risk factors. Diabetic patients are often asymptomatic despite advanced cardiac disease. This study investigates whether preoperative cardiac testing improves the outcome in diabetic patients at risk for cardiac disease. METHODS: We retrospectively reviewed all patients undergoing lower-extremity arterial reconstructions in a 32-month period from July 1999 to February 2002. Of the 433 patients identified undergoing 539 procedures, 295 had diabetes mellitus and considered in this study. The patients were stratified into two groups according to the present American College of Cardiology, American Heart Association (ACC/AHA) algorithm. We identified 140 patients with two or more of ACC (Eagle) criteria who met the inclusion criteria for a preoperative cardiac evaluation. These patients were separated into two groups: those undergoing a cardiac work-up (WU) according to the ACC/AHA algorithm and those not undergoing the recommended work-up (NWU). Outcomes included perioperative mortality, postoperative myocardial infarction, congestive heart failure, arrhythmia, and length of hospitalization. Significance of association was assessed by the Fisher exact test. Length of hospitalization was compared using the Kruskal-Wallis rank sum test. Survival data was analyzed with the Kaplan-Meier method. RESULTS: One hundred forty patients met the criteria for moderate risk. There were 61 patients in the NWU group and 79 in the WU group. Ten patients in the WU group underwent preoperative coronary revascularization (6 had percutaneous transluminal coronary angioplasty, 4 underwent coronary artery bypass grafting). There was no difference between perioperative mortality (WU, 1%; NWU, 2%; P = 1.00) or in postoperative cardiac morbidity, including myocardial infarction, congestive heart failure, and arrhythmia requiring treatment (WU, 5%; NWU, 6%; P = .71). There were no perioperative deaths and one episode of congestive heart failure in the group that had preoperative coronary revascularization. Median length of hospitalization was 10 days in the WU group and 8 days in the NWU group ( P = .11). Patient survival at 12 months for the NWU, WU, and revascularized groups was 85.3%, 78.5%, and 80.0%, respectively; 36-month survival was 73.6%, 62.9%, and 80.0%, respectively. The three survival curves did not differ significantly ( P = .209). CONCLUSIONS: Preoperative cardiac evaluation, as defined by the ACC/AHA algorithm, does not predict or improve postoperative morbidity, mortality, or 36-month survival in asymptomatic, diabetic patients undergoing elective lower-extremity arterial reconstruction. These data do not support the current ACC/AHA recommendations as a standard of care for diabetic patients with an intermediate clinical predictor who undergo peripheral arterial reconstruction, a high-risk surgical procedure.

Timing of pedal bypass failure and its impact on the need for amputation.

Although the utility of dorsalis pedis (DP) bypass for limb ischemia has been well established, the fate of limbs with a failed bypass to the DP artery remains unclear. Data of all patients undergoing DP bypass grafting within a 12-year period from two university hospitals' vascular registries were retrospectively reviewed. Outcomes of early (<30 days) and delayed graft failure (>30 days) were examined. The Student's t-test and chi-squared test were used for univariate analysis; patency rates and patient survival were calculated using the Kaplan-Meier product limit method. Of 1434 DP bypass grafts, 277 (19.3%) failed grafts were identified. Sixty five (4.5%) grafts failed early (within 30 days of surgery) and 212 (14.8%) failed late at a mean time of 15.3 months (range, 1.5-105 months) after initial bypass. Of the 65 limbs with early graft failure, 28 (43.1%) proceeded directly to amputation and 20 underwent additional revascularization attempts, but limb salvage was achieved in only 7 patients; in 45 (69.2%) patients no further revascularizations were attempted. Seventy-four (34.9%) patients with late graft failure underwent redo revascularization. Thirty-nine (52.6%) had their limb saved with graft revision, but 35 patients (47.3%) ultimately lost their limb. In 138 patients with late graft failure (65.1%) no further revascularization attempts were performed. Sixty-two (44.9%) required major amputation. Overall, 49.8% of patients with failed pedal grafts ultimately suffered limb loss. Early graft failure resulted in a significantly higher rate of major amputation that did late graft failure (63.1% vs. 45.8%, respectively; p = 0.015). These results indicate that early occlusion of pedal bypass often leads to immediate major amputation and interventions to maintain graft patency in this setting are often futile. Late failure of pedal bypass is associated with a lower likelihood of amputation because of a higher rate of success of bypass revisions and a lower occurrence of critical ischemia with graft failure.

Popliteal artery aneurysms: a comparison of outcomes in elective versus emergent repair.

OBJECTIVE: The purpose of this study was to assess and compare outcomes of elective versus emergent operative repair of popliteal artery aneurysms. DESIGN: A retrospective analysis of a prospectively recorded vascular surgery database from June 1992 to December 2002 was performed with chart review. Main outcome measures Patient survival, limb salvage, and graft patency were evaluated. RESULTS: Fifty-one popliteal artery aneurysms were repaired in 39 patients, all male and ranging in age from 18 to 87 years (mean 67.1). Mean follow-up was 47.8 months. Repair was elective in 37 (72.5%) and emergent in 14 (27.5%) limbs, 13 with acute ischemia and one with aneurysm rupture. Thrombolytic therapy was utilized in four ischemic limbs with no suitable bypass target vessel identified on initial arteriogram. Outflow vessels included the popliteal artery in 22 (43.1%) and infrapopliteal vessels in 29 (56.9%) limbs. Cardiac morbidity and 30-day mortality rates were 0%. Overall primary patency, secondary patency, limb salvage, and actuarial survival were 95.6%, 100%, 98.0%, and 98.0% at 1 year and 85.1%, 96.9%, 98.0%, and 83.8% at 5 years, respectively. Bypass graft redo or revision was performed for stenosis in one and occlusion in four limbs. Two amputations were performed at 6 days and 63.6 months after initial aneurysm repair. No difference was noted between elective and emergent groups with regard to patency, limb salvage, or survival (P >.26), and no association between the number of identified target vessels and limb salvage or patency was demonstrated (P =.12). CONCLUSION: In our experience, the outcome of the popliteal artery aneurysm repair was comparable in the emergent and elective settings. Aggressive tibial reconstruction plays a crucial role in the treatment of popliteal artery aneurysms, especially in those presenting with acute limb ischemia. Thrombolytic therapy is infrequently required in the acute setting, although it may be useful in patients with no identifiable outflow target vessel on initial arteriogram.

Major lower extremity amputation: outcome of a modern series.

HYPOTHESIS: Major lower extremity amputation results in significant morbidity and mortality. DESIGN: Retrospective database query and medical record review for January 1, 1990, to December 31, 2001. Mean follow-up was 33.6 months. SETTING: Academic tertiary care center. PATIENTS: Nine hundred fifty-nine consecutive major lower extremity amputations in 788 patients, including 704 below-knee amputations (BKAs) (73.4%) and 255 above-knee amputations (AKAs) (26.6%). MAIN OUTCOME MEASURES: Patient survival, cardiac morbidity, infectious complications, and subsequent operation. RESULTS: Overall 30-day mortality was 8.6%, worse for AKA (16.5%) than BKA (5.7%) patients (P<.001). Thirty-day mortality for guillotine amputation for sepsis control was 14.3% compared with 7.8% for closed amputation (P =.03). Complications included cardiac (10.2%), wound infection (5.5%), and pneumonia (4.5%). Twelve AKA (4.7%) and 129 BKA (18.4%) limbs required subsequent operation. Only 66 BKAs (9.4%) required conversion to AKA (average, 77.1 days postoperatively). Overall survival was 69.7% and 34.7% at 1 and 5 years, respectively. Survival was significantly worse for AKAs (50.6% and 22.5%) than BKAs (74.5% and 37.8%) (P<.001). Survival in patients with diabetes mellitus (DM) was 69.4% and 30.9% vs 70.8% and 51.0% in patients without DM at 1 and 5 years, respectively (P =.002). Survival in end-stage renal disease patients was 51.9% and 14.4% vs 75.4% and 42.2% in patients without renal failure at 1 and 5 years, respectively (P<.001). CONCLUSIONS: Major amputation continues to result in significant morbidity and mortality. Survivors with BKA require revision or conversion to AKA infrequently. Long-term survival is dismal for patients with DM and end-stage renal disease and those undergoing AKA.

Outcome of lower-extremity revascularization in patients younger than 40 years in a predominantly diabetic population.

OBJECTIVE: Incidence of perioperative complications is increased and outcome is poor in young patients undergoing vascular surgery. We extensively reviewed results of lower-extremity procedures in this group of patients to further define the extent of short-term and long-term morbidity. METHODS: Results from our vascular registry were retrospectively reviewed for 76 lower-extremity revascularization procedures performed between January 1990 and May 2000 in 51 patients younger than 40 years. This represents 1.88% of 4052 lower-extremity bypass procedures performed during this period. Perioperative cardiac complications, long-term survival, graft patency, and limb salvage were evaluated. Kaplan-Meier curves were generated, and their significance was determined with the Cox-Mantel test. RESULTS: Forty-nine percent of patients were male, and 51% were female; mean age at presentation was 35.9 years (range, 27.5-39.8 years). Preoperative morbidity included diabetes mellitus (96.1%), smoking (70.6%), hypertension (78.4%), coronary artery disease (37.3%), hyperlipidemia (33.3%), and renal dysfunction (52.9%). Overall rate for 30-day postoperative mortality was 0.0%, for myocardial infarction was 0.0%, and for congestive heart failure was 1.32%. Thirty-day graft failure was 11.1% (n = 9). At 1 year, primary patency was 71.0%, secondary patency was 82.5%, and limb salvage was 87.1%; and at 5 years these rates were 51.9%, 63.4%, and 77.2%, respectively. After the initial surgery 11.8% (n = 6) of patients required at least one additional ipsilateral revascularization procedure, 31.3% (n = 16) required a bypass graft in the contralateral limb, and 23.5% (n = 12) ultimately required amputation. In patients who required additional ipsilateral procedures, 1-year primary patency rate was 66.7%, secondary patency rate was 62.5%, and limb salvage rate was 77.8%, compared with 5-year rates of 44.4%, 41.7%, and 64.8%, respectively, representing a decrease in patency compared with primary revascularization procedures. Overall survival at 1 year was 88.2%, compared with 73.3% at 5 years. Patients with preexisting renal disease had significantly decreased survival at 5 years compared with those without renal dysfunction (64.5% vs 82.6%; P =.019). CONCLUSIONS: Our data suggest that age younger than 40 years is not associated with increased perioperative morbidity and mortality. However, these patients have a significant rate of early graft failure and dismal long-term survival, especially in patients with preexisting renal dysfunction. In addition, ipsilateral repeat operations have a marginal success rate.

Recurrent stenosis and contralateral occlusion: high-risk situations in carotid endarterectomy?

Carotid angioplasty and stenting (CAS) has been proposed as a treatment option for carotid occlusive disease in high-risk patients including those with recurrent stenosis (RS) and contralateral occlusion (CO). This study reviews the results of carotid endarterectomy (CEA) in patients with RS and CO. We conducted a retrospective review from our vascular registry of 1670 patients who underwent CEAs ( n = 1950) from January 1990 through December 2001. Procedures included RS 86 (4.4%), CO 112 (5.7%), and control 1752 (89.9%). There were 37 strokes in the entire group (1.9%). Among the high-risk group with RS and CO, there were 6 strokes, (RS n = 2, CO n = 4) 3%. There were 31 strokes in the control group 1.8% ( p = NS). Postoperative TIAs were observed more frequently in patients with CO ( n = 2) or RS ( n = 2), 1.8% and 2.3%, respectively ( p < 0.05). Neck hematomas, intracerebral hemorrhages, and myocardial infarctions did not differ between groups. Three deaths occurred within 30 days (0.15%); one was a patient with CO. Renal failure and symptomatic disease were each associated with a higher risk of perioperative stroke; among patients with renal failure there were 6 strokes (4.6%) p < 0.05, in symptomatic patients there were 26 strokes (2.7%) p < 0.05. Multivariate logistic regression analysis confirmed that preoperative renal disease and surgery for symptomatic disease were both significant predictors of perioperative stroke ( p < 0.05; odds ratio 2.177 and 2.943 respectively) while neither RS nor CO was from these results we concluded that the presence of RS and CO do not increase the risk of perioperative stroke in CEA.

Infrainguinal revascularization after renal transplantation.

BACKGROUND: Although evidence suggests that end-stage renal disease is associated with poor limb salvage and patient survival after arterial revascularization, little is known about the effect of renal transplantation. We analyzed the outcome in patients with renal transplants who underwent infrainguinal bypass procedures. METHODS: Data prospectively entered into our vascular registry were reviewed for all patients who underwent lower extremity bypass procedures from January 1, 1990, through January 31, 2002. Sixty patients were identified who had a functioning renal allograft at infrainguinal revascularization. Kaplan-Meier survival curves were generated for limb salvage, patency, and patient survival and were compared with the Mantel-Cox log- rank test. RESULTS: Sixty patients (40 men, 20 women; mean age, 47.1 years) underwent 76 bypass procedures in 71 limbs. Preoperative demographic data included diabetes (59 of 60 patients, 98.3%), coronary artery disease (26 of 60 patients, 43.3%), and preoperative serum creatinine concentration (SCr) greater than 2.0 mg/dL (9 of 60 patients, 11.7%). Mean follow-up was 25.1 months. Overall major complication rate was 11.8%, and 30-day mortality rate was 1.3%. Survival was 93.3% at 1 year and 66.6% at 5 years. Limb salvage was 87% at 1 year and 78% at 5 years. Primary graft patency was 78% at 1 year and 44% at 5 years. Preoperative SCr less than or equal to 2.0 mg/dL was associated with improved overall patient survival (5-year survival, 73.4% vs 37.5%; P =.01, log-rank test). Limb salvage and patency rates were not significantly affected by preoperative SCr greater than 2.0 mg/dL. CONCLUSIONS: Lower extremity bypass can be performed safely and effectively in patients who have undergone renal transplantation. However, the importance of a well-functioning renal allograft at surgery is demonstrated by marked improvement in patient survival.

A decade of experience with dorsalis pedis artery bypass: analysis of outcome in more than 1000 cases.

OBJECTIVE: The purpose of this study was to review our experience over the last decade with the dorsalis pedis bypass for ischemic limb salvage in patients with diabetes mellitus. METHODS: The study was a retrospective analysis of a computerized vascular registry and chart review. From January 10, 1990 to January 11, 2000, 1032 bypasses to the dorsalis pedis artery were performed in 865 patients (27.6% of the 3731 lower extremity arterial bypass procedures performed in that time period). Five hundred ninety-seven patients (69%) were male, with a mean age of 66.8 years. Ninety-two percent had diabetes mellitus. All procedures were done for limb salvage. Conduits included 317 nonreversed saphenous vein (30.7%), 273 in situ (26.4%), 235 reversed vein (22.8%), 170 arm vein (16.5%), 35 other vein (3.4%), and two polytetrafluoroethylene (0.2%) grafts. The inflow arteries were as follows: 294 common femoral (28.5%), 550 popliteal (53.2%), 114 superficial femoral (11%), and 74 other (7.2%). RESULTS: The mortality rate within 1 month of surgery was 0.9%, and 42 grafts (4.2%) failed in the same interval, although 13 were successfully revised. In a follow-up period that ranged from 1 to 120 months (mean, 23.6 months), primary patency, secondary patency, limb salvage, and patient survival rates were 56.8%, 62.7%, 78.2%, and 48.6%, respectively at 5 years and 37.7%, 41.7%, 57.7%, and 23.8% at 10 years. Both polytetrafluoroethylene grafts failed in less than 1 year. Primary graft patency was worse in female patients (46.5% female versus 61.6% male at 5 years; P <.009) but better in patients with diabetes (65.9% diabetes mellitus versus 56.3% non-diabetes mellitus at 4 years; P <.04). Saphenous vein grafts performed better than all other conduits with a secondary patency rate of 67.6% versus 46.3% at 5 years (P <.0001). Multivariate analysis showed that length of stay greater than 10 days and dorsalis pedis bypass for the surgical indication of previous graft occlusion were independently predictive of worse graft patency at 1 year and use of saphenous vein as conduit was predictive of better patency. CONCLUSION: Dorsalis pedis bypass is durable with a high likelihood of ischemic foot salvage over many years. Saphenous vein is the preferred conduit when available. Short vein grafts from distal inflow sites are possible in more than 50% of cases. These results justify the routine use of pedal arterial reconstruction for patients with diabetes with ischemic foot complications.