Surgical Management of Critical Limb Ischemia

Meta-analysis of outcomes from drug-eluting stent implantation in infrapopliteal arteries

BACKGROUND

Percutaneous drug-eluting stent implantation (DESI) is an emerging and promising treatment modality for infrapopliteal artery diseases (IPADs). This systematic review and meta-analysis summarizes and quantitatively analyzes the outcomes of DESI in IPADs considering the hazard ratio (HR), which is a more accurate and appropriate outcome measure than the more commonly used relative risk and odds ratio.

AIM

To explore the superiority of drug-eluting stents (DESs) vs traditional treatment modalities for IPADs.

METHODS

The following postoperative indicators were the outcomes of interest: All-cause death (ACD)-free survival, major amputation (MA)-free survival, target lesion revascularization (TLR)-free survival, adverse event (AE)-free survival, and primary patency (PP) survival. The outcome measures were then compared according to their respective HRs with 95% confidence intervals (CIs). The participants were human IPAD patients who underwent treatments for infrapopliteal lesions. DESI was set as the intervention arm, and traditional percutaneous transluminal angioplasty (PTA) with or without bare metal stent implantation (BMSI) was set as the control arm. A systematic search in the Excerpta Medica Database (Embase), PubMed, Web of Science, and Cochrane Library was performed on November 29, 2022. All controlled studies published in English with sufficient data on outcomes of interest for extraction or conversion were included. When studies did not directly report the HRs but gave a corresponding survival curve, we utilized Engauge Digitizer software and standard formulas to convert the information and derive HRs. Then, meta-analyses were conducted using a random-effects model.

RESULTS

Five randomized controlled trials and three cohort studies involving 2639 participants were included. The ACD-free and MA-free survival HR values for DESI were not statistically significant from those of the control treatment (P > 0.05); however, the HR values for TLR-free, AE-free, and PP-survival differed significantly [2.65 (95%CI: 1.56-4.50), 1.57 (95%CI: 1.23-2.01), and 5.67 (95%CI: 3.56-9.03), respectively].

CONCLUSION

Compared with traditional treatment modalities (i.e., PTA with or without BMSI), DESI for IPADs is superior in avoiding TLR and AEs and maintaining PP but shows no superiority or inferiority in avoiding ACD and MA.

Meta-analysis of outcomes from drug-eluting stent implantation in infrapopliteal arteries

BACKGROUND

Percutaneous drug-eluting stent implantation (DESI) is an emerging and promising treatment modality for infrapopliteal artery diseases (IPADs). This systematic review and meta-analysis summarizes and quantitatively analyzes the outcomes of DESI in IPADs considering the hazard ratio (HR), which is a more accurate and appropriate outcome measure than the more commonly used relative risk and odds ratio.

AIM

To explore the superiority of drug-eluting stents (DESs) vs traditional treatment modalities for IPADs.

METHODS

The following postoperative indicators were the outcomes of interest: All-cause death (ACD)-free survival, major amputation (MA)-free survival, target lesion revascularization (TLR)-free survival, adverse event (AE)-free survival, and primary patency (PP) survival. The outcome measures were then compared according to their respective HRs with 95% confidence intervals (CIs). The participants were human IPAD patients who underwent treatments for infrapopliteal lesions. DESI was set as the intervention arm, and traditional percutaneous transluminal angioplasty (PTA) with or without bare metal stent implantation (BMSI) was set as the control arm. A systematic search in the Excerpta Medica Database (Embase), PubMed, Web of Science, and Cochrane Library was performed on November 29, 2022. All controlled studies published in English with sufficient data on outcomes of interest for extraction or conversion were included. When studies did not directly report the HRs but gave a corresponding survival curve, we utilized Engauge Digitizer software and standard formulas to convert the information and derive HRs. Then, meta-analyses were conducted using a random-effects model.

RESULTS

Five randomized controlled trials and three cohort studies involving 2639 participants were included. The ACD-free and MA-free survival HR values for DESI were not statistically significant from those of the control treatment (P > 0.05); however, the HR values for TLR-free, AE-free, and PP-survival differed significantly [2.65 (95%CI: 1.56-4.50), 1.57 (95%CI: 1.23-2.01), and 5.67 (95%CI: 3.56-9.03), respectively].

CONCLUSION

Compared with traditional treatment modalities (i.e., PTA with or without BMSI), DESI for IPADs is superior in avoiding TLR and AEs and maintaining PP but shows no superiority or inferiority in avoiding ACD and MA.

Multidisciplinary Approach to PAD: Who's on Your Team?

The complexity of peripheral arterial disease (PAD) and its multiorgan involvement requires the utilization of a multispecialty team approach. Members of this team include a vascular specialty (interventional radiology, cardiology, and vascular surgery), podiatry, orthopedic surgery, primary care, infectious disease, endocrinology, plastic surgery, wound care nursing, and dietetics. A team approach has been proven to significantly improve patient outcomes as well as decreasing amputation rates. In order to promote collaboration and avoid duplication of care, the team can be broken down into three main pillars: medical management, wound care, and revascularization. A complete team approach is vital for this population, with an overall goal to treat all manifestations of the disease and prevent further progression and risk of major sequelae of the disease.

Randomized Study of Noninferiority Comparing Prosthetic and Autologous Vein Above-Knee Femoropopliteal Bypasses

BACKGROUND

The main aim of this study was to compare the 5 years rates of secondary patency of above-knee femoropopliteal revascularizations with autologous veins or prosthetic grafts. The secondary objectives were to compare the rates of primary patency, limb salvage, morbidity, and mortality between the 2 groups.

METHODS

This was a single-blind randomized study of noninferiority (ratio 1:1), carried out in 11 centers of vascular surgery with 2 parallel groups between July 2002 and November 2005. Follow-up finished in May 2011. The monitoring protocol included a clinical examination and an ultrasound control at 1 month, 3 and 6 months, then annually.

RESULTS

One hundred patients were included and randomized in the study, 52 in the prosthetic group and 48 in the autologous vein group. Four patients randomized in the vein group received a prosthetic graft. No patient was excluded from the analysis. In the in intent-to-treat analysis, the 5 years secondary patency was 84.6% in the prosthetic group (IC 95%, 71.9-93.1) and 70.8% in the autologous vein group (IC 95%: 55.9-83.1), and the difference in secondary patency between the prosthetic and the autologous vein groups was 13.8% (IC 95%, -4.4 to 32.0). In the under treatment analysis, the 5 years secondary patency was 96.2% among patients receiving a prosthesis (IC 95%, 80.4-99.9) and 90.5% among patients receiving an autologous vein (IC 95%, 66.9-98.9), and the difference in the rate of patency between prostheses and veins was 5.7% (IC 95%, -13.2 to 24.6). Although there was no significant difference at 5 years, the death rate and the rate of amputation were higher in the prosthetic group.

CONCLUSIONS

Although it is impossible to conclude definitely to the noninferiority of prosthetic bypass compared with venous bypass because of the insufficient number of inclusions, this randomized study nevertheless showed at 5 years the satisfactory results obtained with prostheses compared with autologous vein for above-knee femoropopliteal bypasses.

Optimization of metabolite extraction of human vein tissue for ultra performance liquid chromatography-mass spectrometry and nuclear magnetic resonance-based untargeted metabolic profiling

Tissue extraction optimization for untargeted metabolic profiling.

Critical limb ischemia

Critical limb ischemia (CLI) continues to be a significantly morbid disease process for the aging population. Rigid guidelines for the management of patients with CLI are inappropriate due to the complexities that are involved in optimally treating these patients. A thin line exists in the decision process between medical management vs surgical management by revascularization or amputation, and the perception of "success" in this patient population is evolving. This review explores these issues and examines the challenges the treating physician will face when managing the care of patients with CLI. The epidemiology and natural history of CLI is discussed, along with the pathophysiology of the disease process. A review of the literature in regards to the different treatment modalities is presented to help the physician optimize therapy for patients with CLI. New scoring systems to help predict outcomes in patients with CLI undergoing revascularization or amputation are discussed, and an overview of the current status of patient-oriented outcomes is provided. Finally, we briefly examine emerging therapies for the treatment of CLI and provide an algorithm to help guide the practicing physician on how to approach the critically ischemic limb with regard to the complicated issues surrounding these patients.

Infrapopliteal application of sirolimus-eluting versus bare metal stents for critical limb ischemia: analysis of long-term angiographic and clinical outcome

PURPOSE

To present the 3-year angiographic and clinical results of a prospective registry investigating the performance of sirolimus-eluting stents (SESs) versus bare metal stents (BMSs) for critical limb ischemia (CLI) treatment.

MATERIALS AND METHODS

A single-center double-arm prospective registry included patients with CLI who underwent infrapopliteal revascularization with angioplasty and "bailout" use of an SES or BMS. Clinical and angiographic follow-up was scheduled at regular time intervals. Primary clinical and angiographic endpoints included mortality, limb salvage, primary patency, binary angiographic restenosis (ie, >50%), and clinically driven repeat intervention-free survival. Results were stratified according to stent type, and cumulative proportion outcomes were determined by Kaplan-Meier plots. Multivariable Cox proportional-hazards regression analysis was applied to adjust for confounding factors of heterogeneity.

RESULTS

In total, 103 patients were included in the analysis; 41 (75.6% with diabetes) were treated with a BMS (47 limbs; 77 lesions) and 62 (87.1% with diabetes) with an SES (75 limbs; 153 lesions). At 3 years, SES-treated lesions were associated with significantly better primary patency (hazard ratio [HR], 4.81; 95% CI, 2.91-7.94; P < .001), reduced binary restenosis (HR, 0.38; 95% CI, 0.25-0.58; P < .001), and better repeat intervention-free survival (HR, 2.56; 95% CI, 1.30-5.00; P = .006) versus BMS-treated ones. No significant differences were identified between SESs and BMSs with regard to overall 3-year patient mortality (29.3% vs 32.0%; P = .205) and limb salvage (80.3% vs 82.0%; P = .507).

CONCLUSIONS

Infrapopliteal application of SESs for CLI significantly improves angiographic long-term patency and reduces infrapopliteal vascular restenosis versus BMSs, thereby lessening the rate of clinically driven repeat interventions.

Primary cryoplasty therapy provides durable support for limb salvage in critical limb ischemia patients with infrapopliteal lesions: 12-month follow-up results from the BTK Chill Trial

PURPOSE

To report the 12-month follow-up data from the prospective 16-center Below-the-Knee (BTK) Chill Trial, which examined the use of primary cryoplasty for BTK occlusive disease in patients with critical limb ischemia (CLI).

METHODS

The trial included 108 patients (77 men; mean age 73 +/- 11 years, range 41-101) with CLI (Rutherford categories 4-6) involving 111 limbs with 115 target infrapopliteal lesions. Angiographic inclusion criteria were reference vessel diameter > or = 2.5 mm and < or = 5.0 mm and target lesion stenosis > or = 50%. The primary study endpoints were acute technical success (the ability to achieve < or = 50% residual stenosis and continuous inline flow to the foot) and absence of major amputation of the target limb at 6 months. Secondary endpoints were serious adverse events specifically related to use of primary cryoplasty and absence of major amputation of the target limb at 1, 3, and 12 months.

RESULTS

Acute technical success was achieved in 108 (97.3%) of treated limbs, with only 1 clinically significant dissection (> or = type C) and 2 residual stenoses >50%; stent placement was required following cryoplasty in only 3 (2.7%) procedures. At 6 months and 1 year, major amputation was avoided in 93.4% (85/91) and 85.2% (69/81) of patients, respectively. Through 1 year, 21% (17/81) of patients underwent target limb revascularization. Rates of major amputation and death at 1 year were 0% for limbs of patients with initial Rutherford category 4; 11.4% and 0%, respectively, for initial category 5; and 40.0% and 31.8% for initial category 6. One-year rates of major amputation and death were 20.4% and 8.8%, respectively, for diabetics, versus 4.0% and 10.7% for non-diabetics. At 1 year, major amputation occurred in 16.7% (2/12) of limbs that were expected to be amputated at the time of treatment.

CONCLUSION

Cryoplasty therapy is a safe and effective method of treating infrapopliteal disease, providing excellent results and a high rate of limb salvage in patients with CLI. Study outcomes through 1 year support the use of cryoplasty as a primary treatment option for patients with CLI secondary to BTK occlusive disease.

Sirolimus-eluting versus bare stents after suboptimal infrapopliteal angioplasty for critical limb ischemia: enduring 1-year angiographic and clinical benefit

PURPOSE

To report the 1-year angiographic and clinical outcome from a prospective single-center study investigating the infrapopliteal application of sirolimus-eluting versus bare metal stents in patients with critical limb ischemia (CLI) who underwent below-the-knee endovascular revascularization.

METHODS

Stenting was performed as a bailout procedure for suboptimal angioplasty results (flow-limiting dissection, elastic recoil, or postangioplasty residual stenosis >30%). In the first 29 patients, infrapopliteal stenting was performed with bare metal stents (group B) and with sirolimus-eluting stents in the other 29 patients (group S).

RESULTS

Below-the-knee angioplasty and stenting involved 65 lesions in 40 infrapopliteal arteries of 29 limbs in group B and 66 lesions in 41 infrapopliteal arteries of 29 limbs in group S. Baseline comorbidities (hyperlipidemia and symptomatic cardiac and carotid disease) were more pronounced in group S (p<0.05). At 6 months, sirolimus-eluting stents demonstrated significantly higher primary patency (OR 5.625, 95% CI 1.711 to 18.493, p = 0.004) and decreased in-stent binary restenosis (OR 0.067, 95% CI 0.021 to 0.017, p<0.001) and in-segment binary restenosis (OR 0.229, 95% CI 0.099 to 0.533, p = 0.001). After 1 year, sirolimus-eluting stents were steadily associated with increased primary patency (OR 10.401, 95% CI 3.425 to 31.589, p<0.001) and significantly less in-stent (OR 0.156, 95% CI 0.060 to 0.407, p<0.001) and in-segment (OR 0.089, 95% CI 0.023 to 0.349, p = 0.001) binary restenosis. In addition, sirolimus-eluting stents were associated with significantly fewer cumulative target lesion reinterventions at 6 months (OR 0.057, 95% CI 0.008 to 0.426, p = 0.005) and 1 year (OR 0.238, 95% CI 0.067 to 0.841, p = 0.026). No significant differences between groups B and S were noted at 1 year with respect to mortality (10.3% versus 13.8%, respectively), minor amputation (17.2% versus 10.3%), or limb salvage (100% versus 96%).

CONCLUSION

The application of sirolimus-eluting stents reduces the restenosis rate in the infrapopliteal arteries and the rate of repeat endovascular procedures the first year after treatment.