Revascularization For Chronic Limb Ischemia Research Articles

Frailty predicts poor longer-term outcomes in patients following lower limb open surgical revascularization.

Frailty in vascular surgery patients is increasingly recognized as a marker of poor outcome. This provides particular challenges for patients with lower limb peripheral arterial disease who require surgical revascularization. This study aimed to assess the impact of frailty on short- and long-term outcome in this specific patient group using a specialty specific frailty score. Patients undergoing open surgical revascularization for chronic limb ischemia (January 2015-December 2016) were assessed. Demographics, mode of admission, diagnosis, and site of surgery were recorded alongside a variety of frailty-specific characteristics. We calculated the previously validated Addenbrookes Vascular Frailty Score (AVFS) and Long AVFS (LAVFS). Primary outcome was 3-year mortality. Two hundred and sixty-one patients (75% men, median age 69 years) were studied. The median length of stay was 6 days with a 3-year mortality of 23%. The predictive power of vascular frailty scores showed that for 3-year mortality, area under the receiver operator curve values (AUROC) were specific for both the AVFS score (AUROC: 0.724, 95% CI: 0.654-0.794) and LAVFS Score (AUROC: 0.741, 95%CI: 0.670-0.813). Furthermore, the cumulative AVFS and LAVFS scores both predicted mortality over the follow-up period (P=0.0001) with increased mortality among patients with higher scores. Incremental worsening of frailty, determined using a specialty specific frailty score, predicts mortality risk in patients undergoing lower limb surgical revascularization.

Neutrophil-lymphocyte ratio as a link between complex pedal ulcers and poor clinical results after infrainguinal surgical revascularization

Our aim was to evaluate the influence of preoperative neutrophil-lymphocyte ratio (NLR) on patency and clinical results after infrainguinal surgical revascularization for chronic limb ischemia. Retrospective analysis of 150 infrainguinal autologous bypasses performed to infragenicular popliteal artery or tibial vessels in 140 (93%) patients with chronic limb-threatening ischemia (CLTI) and in 10 (7%) with disabling claudication. NLR was calculated using blood samples obtained 24 hours preoperatively. The cohort was stratified into 2 groups according to interquartile ranges of NLR: "ELEVATED-NLR" (Quartile 4 N.=37) and "LOW-NLR" (Quartile 1-2-3 N.=113). Reperfused ulcers were described using the WIfI classification. Patency, freedom from MALE and amputation-free survival at 24 months were calculated using the Kaplan-Meier method. Univariate comparisons between NLR groups were performed using the Log-Rank test. Statistical differences on univariate analysis were adjusted in a multivariate model (Cox regression). NLR values were similar between CLTI and claudication. Ischemic ulcers were more frequent, (83.4% vs. 59.3% P<0.01), more severe (W2-3: 37.8% vs. 22.1% P=0.01) and pedal infection was deeper (fI 2-3: 40.5% vs. 18.6% P=0.003) in "ELEVATED-NLR" group. Severe ischemia (I3) was similar between groups. High NLR values were independent predictors of patency loss (HR: 1.77 CI95% [1.01-3.10] P=0.04), MALE (HR: 2.04 CI95% [1.03-4.04] P=0.04) and worse amputation-free survival (HR:2.10 CI95% [1.06-4.14] P=0.03) rates at 24 months. High preoperative NLR values are associated with severe and deep infected ulcers and predicts primary patency loss, higher major adverse limb events and worse amputation-free survival rates on long-term follow-up after infrainguinal surgical revascularization.

High plateletcrit is associated with early loss of patency after open and endovascular interventions for chronic limb ischemia

ObjectivePlateletcrit (PCT) reflects the total platelet mass in blood and can be calculated from a complete blood count. We examined the effect of PCT on outcomes of endovascular and open interventions for chronic limb ischemia. MethodsPatients who underwent revascularization for chronic limb ischemia (Rutherford categories 3-6) between June 2001 and December 2014 were retrospectively identified. PCT on admission was recorded. Patients and limbs were divided into tertiles of low (0.046-0.211), medium (0.212-0.271), and high (0.272-0.842) PCT. Patency, limb salvage, major adverse limb events, major adverse cardiac events, and survival rates were calculated using Kaplan-Meier analysis and compared with log-rank test. Cox regression analysis was used for multivariate analysis. ResultsA total of 1431 limbs (1210 patients) were identified and divided into low PCT (477 limbs in 407 patients), medium PCT (477 limbs in 407 patients), and high PCT (477 limbs in 396 patients) groups. The patients in the high tertile were 2 years older that the patients in the other two tertiles (P = .009). Five-year primary patency was 65% ± 3% in the low-PCT group compared with 55% ± 3% and 51% ± 3% in the medium and high PCT groups, respectively (P = .004). Five-year secondary patency was 81% ± 2% in the low PCT group compared with 82% ± 2% and 72% ± 3% in the medium and high PCT groups, respectively (P = .02). Five-year limb salvage rate was 86% ± 2% in the low PCT group compared with 79% ± 3% and 74% ± 3% in the medium PCT and high PCT groups, respectively (P = .004). Multivariate regression analysis showed that low PCT was independently associated with primary patency after endovascular interventions (hazard ratio, 0.67 [0.47-0.95]; P = .02) but not after open interventions (hazard ratio, 0.72 [0.43-1.21]; P = .21). ConclusionsHigh PCT is associated with poor patency and limb salvage rates after interventions for lower extremity chronic limb ischemia. Multivariate regression analysis confirmed association of low PCT with improved primary patency after endovascular interventions but not after open interventions. High PCT may be a marker of increased platelet reactivity and could be used to identify patients at high risk for early thrombosis and failure after interventions.

Metformin Is Associated with Improved Survival and Decreased Cardiac Events with No Impact on Patency and Limb Salvage after Revascularization for Peripheral Arterial Disease

The incidence of cardiovascular and limb-specific adverse outcomes is higher in peripheral arterial disease (PAD) patients with diabetes. Metformin is associated with improved cardiovascular morbidity and mortality. However, the effect of metformin on limb-specific outcomes is unclear. The objective of this study was to assess the effect of metformin on outcomes after intervention for PAD. Patients who underwent revascularization for chronic limb ischemia (Rutherford 3-6) between June 2001 and December 2014 were retrospectively identified. Primary patency (PP), secondary patency (SP), limb salvage (LS), major adverse limb events (MALE), major adverse cardiac events (MACE), and survival rates were compared using Kaplan-Meier and Cox regression. One thousand sixty-four limbs in 1204 patients were identified (147 metformin, 196 other hypoglycemics [OH], 216 insulin, and 645 nondiabetics (nondiabetes mellitus [DM]). Non-DM had significantly lower incidence of CAD (46%) than insulin (65%), metformin (56%), and OH groups (63%) (P<0.001). Insulin patients (17%) had significantly higher incidence of end-stage renal disease (ESRD) than non-DM (3%), metformin (1.4%), and OH groups (8%) (P<0.001). Ninety four percent of patients in the metformin group were on aspirin, which was significantly higher than non-DM (86%), OH (83%), and insulin groups (86%) (P=0.02). Similarly, statin use was significantly higher in the metformin group (71%) than in OH (64%), insulin (61%), and non-DM groups (55%) (P=0.002). Majority of patients in the insulin group presented with critical limb ischemia (CLI) (93%), which was significantly greater than the metformin (59%), OH (72%), and non-DM groups (50%) (P<0.001). Sixty-month PP was significantly greater in non-DM group (62%) (P=0.005) in overall comparison with no significant difference between metformin (56%), OH (60%), and insulin (51%) groups (P=0.06). Sixty-month SP was similar in metformin (76%), OH (85%), insulin (76%), and non-DM (80%) groups (P=0.27). LS was significantly worse in insulin group (62%) (P<0.001) with no significant difference between metformin (84%), OH (83%), and non-DM (87%) groups (P=0.45). Freedom from MALE at 60 months was 53% in the insulin group, which was significantly worse as compared with metformin (71%), OH (70%), and non-DM (67%) groups (P=0.001). Sixty-month survival was significantly improved in metformin (60%) and non-DM (60%) groups as compared with that in OH (41%) and insulin groups (30%) (P<0.001). Freedom from MACE was significantly greater in metformin (44%) and non-DM (52%) groups than that in OH (37%) and insulin groups (25%) (P<0.001). Metformin use (HR, 0.7 [0.5-0.9]; P=0.008) was an independent factor associated with freedom from mortality. Metformin is associated with improved survival and decreased incidence of adverse cardiac events in PAD patients. However, it did not have an impact on patency or LS rates after open and endovascular interventions. LS was worse in diabetic patients primarily treated with insulin.

Metformin Is Associated With Improved Survival and Decreased Cardiac Events With No Impact on Patency and Limb Salvage After Revascularization for Chronic Limb Ischemia

Metformin Is Associated With Improved Survival and Decreased Cardiac Events With No Impact on Patency and Limb Salvage After Revascularization for Chronic Limb Ischemia

Tratamento endovascular da isquemia crónica dos membros inferiores dos doentes em hemodiálise: resultados clínicos

IntroductionThe peripheral vascular atherosclerotic disease is a characteristic complication in patients with end‐stage renal disease (ESRD) and shows a particular predilection for diffuse, calcifying and infra‐popliteal involvement. Despite the advances in endovascular revascularization, the clinical efficacy in these patients is limited and poor results are expected. PurposeDetermine the clinical outcomes after endovascular revascularization for chronic limb ischemia in patients with ESRD on dialysis and compare the results with patients not on dialysis. Material and methodsWe retrospectively evaluate the results of patients who underwent endovascular revascularization for chronic limb ischemia, between January 2010 and December 2013. The patients were divided into two groups: those with normal renal function and those with end stage renal disease on dialysis. The primary end points were: limb salvage and mortality and the secondary endopoints: technical success, wound healing rate, time for wound healing and complications. ResultsOf the total of 217 patients, 32 patients were excluded due to absence of data and 9 patients with renal insuficiency but not end‐stage. 176 patients underwent endovascular revascularization (a total of 182 limbs, median age of 65 years old, 78% males). 45 patients were on dyalisis program. Median follow‐up was 26,6 months.In patients with Rutherford categories 4, 5 and 6, the limb salvage rate, at 12 months, was 90,4% in patients not on dialysis, and 69,6% in patients on dialysis. The survival rate at 12 monts was lower in patients on dialysis (86% vs 97,1%)The wound healing rate was also lower in patients on dialysis (60% vs 80%) and with longer median healing times (96 vs 61 days) DiscussionThe presence of end stage renal disease is associated with a higher rate of limb loss and mortality. Despite the discouraging results, for these patients, it should be offered the less invasive endovascular revascularization treatment and an earlier referral.

Low levels of high-density lipoproteins are associated with acute kidney injury following revascularization for chronic limb ischemia

Objectives: Perioperative acute kidney injury (AKI) is not uncommon, following revascularization. HDL has been shown to reduce organ injury in animal models. The aim of the study is to examine the association of HDL on AKI in patients undergoing revascularization for chronic limb ischemia. Methods: All patients who underwent revascularization between June 2001 and December 2009 were analyzed. Patients on dialysis and with incomplete data were excluded. Patients were grouped for HDL < or ≥40 mg/dL. Univariate and multivariate analysis were used to identify factors associated with AKI. Results: A total of 684 patients were included. Eighty-two (12.0%) patients developed postoperative AKI (15.7% in low HDL group vs. 6.3% in high HDL group, p < 0.001). The AKI group were more likely to be older (71.5 ± 10.1 vs. 68.0 ± 10.8, p = 0.01), ASA 4 class (26% vs. 14%, p < 0.001), to have albumin <3 g/dL (59% vs. 32%, p < 0.001), low HDL levels (79% vs. 58%, p < 0.001), DM (61% vs. 44%, p = 0.005), CAD (67% vs. 55%, p = 0.003), preoperative chronic kidney disease (CKD) stage III–IV (55% vs.39%, p < 0.001), to present with critical limb ischemia (82% vs. 63%, p = 0.001), and to be on ACEI (67% vs. 51%, p = 0.006). Multivariate logistic regression analysis showed low HDL (Odds Ratio (OR) 1.66 [1.23–2.24]) and serum albumin levels <3 g/dL (OR 1.66 [1.29–2.13], p < 0.001) were independently associated with increased odds for developing AKI. Propensity score analyses showed low HDL was independently associated with increased odds of AKI (OR 2.4 (1.4–4.2)). Conclusions: AKI following revascularization is not uncommon (12.0%), and lower concentrations of HDL and serum albumin are associated with increased odds of postoperative AKI. There was also a trend of higher prevalence of AKI among those with pre-existing CKD.

Clinical presentation and outcome after failed infrainguinal endovascular and open revascularization in patients with chronic limb ischemia

Failure of prior endovascular (EV) interventions for chronic limb ischemia has been reported to negatively affect patency and limb salvage after subsequent revascularization procedures. The goal of our study was to compare the clinical presentation of patients who failed infrainguinal EV and open revascularizations (OR) and the effect of the initial intervention on final outcomes. From June 2001 to October 2010, 216 patients (237 limbs; 66 disabling claudication [DC], 171 critical limb ischemia [CLI]) presented with failed infrainguinal OR or EV revascularization for chronic limb ischemia. Clinical presentation, reinterventions, patency and limb salvage rates, and final outcomes were analyzed. The EV group (n = 143) had more diabetes (44% vs 57%; P = .048) and ulcers (26% vs 38%; P = .039), whereas the OR group (n = 94) had more multilevel revascularizations (59% vs 33%; P < .001), rest pain (23% vs 9%; P = .002), and infrapopliteal interventions (58% vs 38%; P = .038). Presentation at time of failure was non-limb-threatening ischemia in 70% of DC and 16% of CLI patients (P < .001), with no difference in those initially treated with EV or OR. In CLI, 23% presented with acute limb ischemia in the OR group vs 10% in the EV group (P = .024). Early failure (<3 months) occurred in 15% of DC and in 36% of CLI patients and was more in the OR than in the EV group (30% vs 7% for DC [P = .011] and 71% vs 38% for CLI [P = .024]). Overall, 195 (82%) had attempted reinterventions (79% in DC and 85% in CLI; P = .245). In DC patients, 48% of OR had OR + EV and 26% had EV; 32% of EV had OR + EV and 47% had EV reinterventions. In CLI patients, 40% of OR had OR + EV and 42% had EV; 17% of EV had OR + EV; and 70% had EV reinterventions. A patent revascularized limb was achieved in 66% of OR and in 92% of EV patients (P < .001). Patency and limb salvage were significantly better in the EV group, mainly due to the difference in CLI patients, whereas survival was identical. Clinical presentation after failed infrainguinal revascularization is determined by the initial indication. CLI patients are more likely to present early with acute limb ischemia, especially after OR. EV reinterventions play a significant role in the management of patients with failed revascularization, and EV failure is associated with better outcomes than those after OR failure, likely due to OR patients having more disadvantaged anatomy and advanced disease at the time of their initial presentation.

Low Levels of High-Density Lipoproteins Are Associated With Acute Kidney Injury Following Revascularization for Chronic Limb Ischemia

Low Levels of High-Density Lipoproteins Are Associated With Acute Kidney Injury Following Revascularization for Chronic Limb Ischemia

Orbital atherectomy for infrapopliteal disease: Device concept and outcome data for the OASIS trial

The purpose of this study was to assess the safety and short-term efficacy of orbital atherectomy for chronic infrapopliteal arterial occlusive disease. Infrapopliteal occlusive disease is a common cause of critical limb ischemia and claudication. There are no American College of Cardiology/American Heart Association guidelines for infrapopliteal revascularization for chronic limb ischemia. One hundred twenty four patients (201 stenoses) were enrolled in a prospective non-randomized multicenter registry of orbital atherectomy for severe infrapopliteal disease. Data were collected as part of an investigational device exemption from the Food and Drug Administration. The primary safety endpoint of major adverse events (MAE) at 30-days (death, myocardial infarction, amputation, or repeat revascularization) was observed in four patients (3.2%). The primary efficacy endpoint (final diameter stenosis) was 17.8 +/- 13.5%. The secondary endpoints of procedural success (final diameter stenosis < or =30%) and 6 month MAE (death, amputation, or target vessel revascularization) were observed in 90.1 and 10.4% of patients, respectively. Stand-alone atherectomy was performed in 116 lesions (57.4%). At 6-months, no patients required surgical bypass or unplanned amputation, and improvement in Rutherford ordinal scale was observed in 78.2% of patients. Orbital atherectomy is a unique approach to infrapopliteal disease, and provides predictable and safe lumen enlargement. Short-term data demonstrate substantial symptomatic improvement and infrequent need for further revascularization or amputation.

Percutaneous Endovascular Treatment for Chronic Limb Ischemia

Percutaneous transluminal methods of revascularization for chronic limb ischemia have traditionally been used as an adjunctive or secondary mode of treatment. This study examines the outcomes of patients treated via endovascular methods as the primary form of treatment. The records of 66 patients (average age, 71.3 years; range, 53 to 92) with chronic limb ischemia treated from November 2000 to January 2002 at a single institution with endovascular methods were retrospectively reviewed. Thirty-one patients had disabling claudication, 15 had rest pain, 17 had minor tissue loss, and 3 had major tissue loss. There were 94 lesions in the 66 limbs: 45 lesions in the superficial femoral artery, 28 lesions in the popliteal artery, and 21 lesions in tibial arteries. Occlusive lesions were treated by subintimal angioplasty. Stenoses were treated by percutaneous transluminal angioplasty (PTA). The median length of the lesions was 12 cm. Forty-six stents were placed in 32 patients; 34 patients did not receive stents. The approach was contralateral in 71% (47/66) and ipsilateral in 29% (19/66) of cases. Patients were followed up with physical exam, anklebrachial index (ABI), and duplex ultrasonography. Post-intervention medical treatment included aspirin and clopidogrel. Long-term patency was correlated with age, comorbidities, risk factors, and the use of stents in addition to angioplasty. Endovascular treatment was technically successful in 65 of 66 patients (98%). Residual stenosis (<30%) was found in three cases, two in patients with PTA alone and one patient with PTA and a stent. Mean length of follow-up was 6.3 months (range, 6 weeks to 15 months). Post-intervention ABI improved from a mean of 0.65 to a mean of 1.01 (p < 30.05). The perioperative complication rate was 9% and included three cases of hematoma and one case each of thrombosis, lymphocele, and rash reaction to medications. Outcome measures included primary patency (89%), assisted primary patency (96%), and limb salvage (97%) at 6 months. Restenosis of >50% occurred in four patients and occlusion occurred in two. At 6 months, patients with one or more stents had a patency rate of 84% (27/32), whereas those without a stent had a patency rate of 94% (32/34) (p = NS). Endovascular treatment is a safe, feasible, and effective method with a high short-term patency rate and may be used as an alternative to bypass for chronic limb ischemia.

Results of a Prospective Randomized Trial Evaluating Surgery Versus Thrombolysis for Ischemia of the Lower Extremity The STILE Trial

This study was designed to evaluate intra-arterial thrombolytic therapy as part of a treatment strategy for patients requiring revascularization for lower limb ischemia caused by nonembolic arterial and graft occlusion. Patients with native arterial or bypass graft occlusion were randomized prospectively to either optimal surgical procedure or intra-arterial, catheter-directed thrombolysis with recombinant tissue plasminogen activator (rt-PA) or urokinase (UK). Thrombolysis patients required successful catheter placement into the occlusion before infusion of either rt-PA at 0.05 mg/kg/hr for up to 12 hours or UK of 250,000 units bolus followed by 4000 units/min x 4 hours, then 2000 units/min for up to 36 hours. A composite clinical outcome of death, ongoing/recurrent ischemia, major amputation, and major morbidity was the primary endpoint. Additional endpoints were reduction in surgical procedure, clinical outcome classification, length of hospitalization, and outcome by duration of ischemia. Randomization was terminated at 393 patients because a significant primary endpoint occurred by the first interim analysis. Failure of catheter placement occurred in 28% of patients who were randomized to lysis, and thus, were considered treatment failures. Thirty-day outcomes demonstrated significant benefit to surgical therapy compared with thrombolysis (p < 0.001), primarily because of a reduction in ongoing/recurrent ischemia (p < 0.001). However, clinical outcome classification at 30 days was similar. Stratification by duration of ischemia indicated that patients with ischemic deterioration of 0 to 14 days had lower amputation rates with thrombolysis (p = 0.052) and shorter hospital stays (p < 0.04). Patients with ischemic deterioration of > 14 days who who were treated surgically had less ongoing/recurrent ischemia (p < 0.001) and trends toward lower morbidity (p = 0.1). At 6-month follow-up, there was improved amputation-free survival in acutely ischemic patients treated with thrombolysis (p = 0.01); however, chronically ischemic patients who were treated surgically had significantly lower major amputations rates (p = 0.01). More than half of thrombolysis patients (55.8%) had a reduction in magnitude of their surgical procedure (p < 0.001). There was no difference in efficacy or safety between rt-PA and UK; however, in the thrombolysis group as a whole, fibrinogen depletion predicted hemorrhagic complications (p < 0.01). Surgical revascularization of patients with < 6 months of ischemia is more effective and safer than catheter-directed thrombolysis. Although ongoing/recurrent ischemia is greater in the patients undergoing thrombolysis, 30-day clinical outcomes are similar, probably because of cross-over treatment to surgery. There is no difference in efficacy or safety between rt-PA and UK, although bleeding occurs in patients with greater fibrinogen depletion. A significant reduction in planned surgical procedure is observed after thrombolysis. Patients with acute ischemia (0-14 days) who were treated with thrombolysis had improved amputation-free survival and shorter hospital stays. However, for patients with chronic ischemia (> 14 days), surgical revascularization was more effective and safer than thrombolysis. Combining a treatment strategy of catheter-directed thrombolysis for acute limb ischemia with surgical revascularization for chronic limb ischemia offers the best overall results.