Outcomes of Isolated Tibial Endovascular Interventions for Tissue Loss in CLI Patients on Hemodialysis

Association between End-Stage Renal Disease and Major Adverse Limb Events after Peripheral Vascular Intervention

PURPOSE

To examine the effect of end-stage renal disease (ESRD) on the likelihood of major adverse limb events (MALEs) in patients with Rutherford Category 4-6 critical limb ischemia (CLI) who underwent percutaneous vascular intervention (PVI).

MATERIALS AND METHODS

Two contemporaneous cohorts of patients who underwent PVI for symptomatic CLI from 2012 to 2022, differing in ESRD status, were matched using propensity score methods. This database identified 628 patients who underwent 1,297 lower extremity revascularization procedures; propensity score matching yielded 147 patients (180 limbs, 90 limbs in each group). Kaplan-Meier and Cox proportional hazard analyses were used to assess the effect of ESRD status on MALEs, stratified into major amputation (further stratified into above-knee amputation and below-knee amputation [BKA]) and reintervention (PVI or bypass).

RESULTS

After PVI, 31.3% of patients in the matched cohorts experienced a MALE (45.7% ESRD vs 18.2% non-ESRD), and 15.6% experienced a major amputation (27.1% ESRD vs 5.2% non-ESRD). Cox proportional hazards analysis revealed that ESRD was an independent predictor of MALE (hazard ratio [HR], 3.15; 95% CI, 1.58-6.29; P = .001), major amputation (HR, 7.00; 95% CI, 2.06-23.79; P = .002), and BKA (HR, 7.56; 95% CI, 1.71-33.50; P = .008).

CONCLUSIONS

ESRD is strongly predictive of MALE and major amputation risk, specifically BKA, in patients undergoing PVI for Rutherford Category 4-6 CLI. These patients warrant closer follow-up, and new methods may become necessary to predict and further reduce their amputation risk.

10-Year clinical outcomes of hemodialysis patients with peripheral arterial disease due to infrainguinal disease undergoing endovascular therapy

Although symptomatic peripheral arterial disease (PAD) is common in patients with hemodialysis (HD), few studies have evaluated the long-term clinical outcomes of revascularization in this population. The aim of the current study was to investigate the 10-year clinical outcomes of HD patients with PAD undergoing endovascular therapy (EVT). We retrospectively analyzed 750 limbs from 578 HD patients with symptomatic PAD due to infrainguinal lesions, treated with EVT, between May 2004 and November 2011. The primary outcome was 10-year mortality and the secondary outcome was 10-year freedom from major adverse limb events (MALEs). Predictors for each outcome were evaluated by Cox proportional-hazards model. The 10-year rate of survival and freedom from MALEs was 23.6 ± 3.1% and 76.4 ± 2.9%, respectively. In the multivariate analysis, patients with over 80 years [hazard ratio (HR) 2.10; 95% confidence interval (CI) 1.58-2.80; p < 0.001], non-ambulatory status (HR 1.55; 95% CI 1.19-2.03; p = 0.001), absence of hypertension (HR 1.59; 95% CI 1.19-2.08; p = 0.001), heart failure (HR 1.36; 95% CI 1.02-1.80; p = 0.03), and tissue loss (HR 1.65; 95% CI 1.28-2.12; p < 0.001) were at an increased risk of 10-year mortality. Cerebrovascular diseases (HR 1.60; 95% CI 1.03-2.49; p = 0.038), no cilostazol use (HR 1.69; 95% CI 1.09-2.70; p = 0.021), tissue loss (HR 3.87; 95% CI 2.37-6.34; p < 0.001), and poor below-the-knee (BTK) run-off (HR 1.68; 95% CI 1.04-2.71; p = 0.035) were significantly associated with MALEs. After risk stratification analysis based on risk score assignment according to number of predictors, 10-year survival and freedom from MALE were lower in the higher score groups (10-year survival rates according to number of risk factors: 0, 35.1%; 1, 20.3%; 2-5, 10.8%; respectively, p < 0.001, 10-year freedom from MALE rates in patients with greater number of risk factors: 0-1, 90.2%; 2-3, 65.5%; 4-5, 61.6%; respectively, p < 0.001). The 10-year clinical outcomes after EVT for HD patients with PAD due to infrainguinal disease were clinically suboptimal. Risk stratification based on these predictors before EVT would be useful in estimating future adverse outcome.

The comparative and added prognostic value of biomarkers to the Revised Cardiac Risk Index for preoperative prediction of major adverse cardiac events and all-cause mortality in patients who undergo noncardiac surgery

BACKGROUND

The Revised Cardiac Risk Index (RCRI) is a widely acknowledged prognostic model to estimate preoperatively the probability of developing in-hospital major adverse cardiac events (MACE) in patients undergoing noncardiac surgery. However, the RCRI does not always make accurate predictions, so various studies have investigated whether biomarkers added to or compared with the RCRI could improve this.

OBJECTIVES

Primary: To investigate the added predictive value of biomarkers to the RCRI to preoperatively predict in-hospital MACE and other adverse outcomes in patients undergoing noncardiac surgery. Secondary: To investigate the prognostic value of biomarkers compared to the RCRI to preoperatively predict in-hospital MACE and other adverse outcomes in patients undergoing noncardiac surgery. Tertiary: To investigate the prognostic value of other prediction models compared to the RCRI to preoperatively predict in-hospital MACE and other adverse outcomes in patients undergoing noncardiac surgery.

SEARCH METHODS

We searched MEDLINE and Embase from 1 January 1999 (the year that the RCRI was published) until 25 June 2020. We also searched ISI Web of Science and SCOPUS for articles referring to the original RCRI development study in that period.

SELECTION CRITERIA

We included studies among adults who underwent noncardiac surgery, reporting on (external) validation of the RCRI and: - the addition of biomarker(s) to the RCRI; or - the comparison of the predictive accuracy of biomarker(s) to the RCRI; or - the comparison of the predictive accuracy of the RCRI to other models. Besides MACE, all other adverse outcomes were considered for inclusion.

DATA COLLECTION AND ANALYSIS

We developed a data extraction form based on the CHARMS checklist. Independent pairs of authors screened references, extracted data and assessed risk of bias and concerns regarding applicability according to PROBAST. For biomarkers and prediction models that were added or compared to the RCRI in ≥ 3 different articles, we described study characteristics and findings in further detail. We did not apply GRADE as no guidance is available for prognostic model reviews.

MAIN RESULTS

We screened 3960 records and included 107 articles.   Over all objectives we rated risk of bias as high in ≥ 1 domain in 90% of included studies, particularly in the analysis domain. Statistical pooling or meta-analysis of reported results was impossible due to heterogeneity in various aspects: outcomes used, scale by which the biomarker was added/compared to the RCRI, prediction horizons and studied populations.  Added predictive value of biomarkers to the RCRI Fifty-one studies reported on the added value of biomarkers to the RCRI. Sixty-nine different predictors were identified derived from blood (29%), imaging (33%) or other sources (38%). Addition of NT-proBNP, troponin or their combination improved the RCRI for predicting MACE (median delta c-statistics: 0.08, 0.14 and 0.12 for NT-proBNP, troponin and their combination, respectively). The median total net reclassification index (NRI) was 0.16 and 0.74 after addition of troponin and NT-proBNP to the RCRI, respectively. Calibration was not reported. To predict myocardial infarction, the median delta c-statistic when NT-proBNP was added to the RCRI was 0.09, and 0.06 for prediction of all-cause mortality and MACE combined. For BNP and copeptin, data were not sufficient to provide results on their added predictive performance, for any of the outcomes. Comparison of the predictive value of biomarkers to the RCRI  Fifty-one studies assessed the predictive performance of biomarkers alone compared to the RCRI. We identified 60 unique predictors derived from blood (38%), imaging (30%) or other sources, such as the American Society of Anesthesiologists (ASA) classification (32%). Predictions were similar between the ASA classification and the RCRI for all studied outcomes. In studies different from those identified in objective 1, the median delta c-statistic was 0.15 and 0.12 in favour of  BNP and NT-proBNP alone, respectively, when compared to the RCRI, for the prediction of MACE. For C-reactive protein, the predictive performance was similar to the RCRI. For other biomarkers and outcomes, data were insufficient to provide summary results. One study reported on calibration and none on reclassification. Comparison of the predictive value of other prognostic models to the RCRI   Fifty-two articles compared the predictive ability of the RCRI to other prognostic models. Of these, 42% developed a new prediction model, 22% updated the RCRI, or another prediction model, and 37% validated an existing prediction model. None of the other prediction models showed better performance in predicting MACE than the RCRI. To predict myocardial infarction and cardiac arrest, ACS-NSQIP-MICA had a higher median delta c-statistic of 0.11 compared to the RCRI. To predict all-cause mortality, the median delta c-statistic was 0.15 higher in favour of ACS-NSQIP-SRS compared to the RCRI. Predictive performance was not better for CHADS₂, CHA₂DS₂-VASc, R₂CHADS₂, Goldman index, Detsky index or VSG-CRI compared to the RCRI for any of the outcomes. Calibration and reclassification were reported in only one and three studies, respectively.

AUTHORS' CONCLUSIONS

Studies included in this review suggest that the predictive performance of the RCRI in predicting MACE is improved when NT-proBNP, troponin or their combination are added. Other studies indicate that BNP and NT-proBNP, when used in isolation, may even have a higher discriminative performance than the RCRI. There was insufficient evidence of a difference between the predictive accuracy of the RCRI and other prediction models in predicting MACE. However, ACS-NSQIP-MICA and ACS-NSQIP-SRS outperformed the RCRI in predicting myocardial infarction and cardiac arrest combined, and all-cause mortality, respectively. Nevertheless, the results cannot be interpreted as conclusive due to high risks of bias in a majority of papers, and pooling was impossible due to heterogeneity in outcomes, prediction horizons, biomarkers and studied populations. Future research on the added prognostic value of biomarkers to existing prediction models should focus on biomarkers with good predictive accuracy in other settings (e.g. diagnosis of myocardial infarction) and identification of biomarkers from omics data. They should be compared to novel biomarkers with so far insufficient evidence compared to established ones, including NT-proBNP or troponins. Adherence to recent guidance for prediction model studies (e.g. TRIPOD; PROBAST) and use of standardised outcome definitions in primary studies is highly recommended to facilitate systematic review and meta-analyses in the future.

End-stage renal disease patients undergoing angioplasty and bypass for critical limb ischemia have worse outcomes compared to non-ESRD patients: Systematic review and meta-analysis

BACKGROUND

End-stage renal disease (ESRD) is associated with increased morbidity and mortality following lower extremity amputation for critical limb ischemia (CLI). Angioplasty and bypass are used in ESRD patients with CLI; however, the treatment of choice remains controversial. We compared the long-term outcomes in patients with CLI undergoing angioplasty or bypass to evaluate the differences between patients with ESRD and those without ESRD.

METHODS

Established databases were searched for observational studies comparing outcomes following bypass or angioplasty for CLI in patients with ESRD to those in non-ESRD patients. End points included survival, limb salvage, amputation-free survival (AFS), and primary and secondary patency at 1-year post-procedure. Pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated using a random effect model.

RESULTS

We included 20 studies with a total of 24,851 patients. ESRD patients compared to non-ESRD patients with CLI had significantly lower survival post-angioplasty (OR 0.51, 95% CI 0.36-0.72, p < .001) and post-bypass (OR 0.26, 95% CI 0.15-0.45, p < .001). ESRD patients had lower rates of limb salvage post-bypass (OR 0.33, 95% CI 0.21-0.53, p < .001) and post-angioplasty (OR 0.54, 95% CI 0.41-0.70, p < .001). AFS was significantly lower in ESRD patients compared to non-ESRD patients following angioplasty (OR 0.48, 95% CI 0.32-0.71, p < .001) and bypass (OR 0.28, 95% CI 0.16-0.47, p < .001) despite no significant differences in primary patency. ESRD patients had overall worse secondary patency post-angioplasty and/or bypass (OR 0.54, 95% CI 0.32-0.94, p = .03) compared to non-ESRD patients. A meta-analysis of four studies directly comparing survival in ESRD patients with CLI based on whether they underwent angioplasty or bypass showed no difference (OR 0.93, 95% CI 0.64-1.35, p = .69).

CONCLUSION

ESRD patients have worse survival, limb salvage, and AFS outcomes following angioplasty and bypass for CLI compared to non-ESRD patients. Large randomized controlled trials comparing these two modalities of treatment in this patient population are needed for further clarity.

Six-month pivotal results of tack optimized balloon angioplasty using the Tack Endovascular System in below-the-knee arteries

OBJECTIVE

No vascular implant is commercially available in the United States to treat post-angioplasty dissections in below-the-knee (BTK) arteries. The Tack Endovascular System (Intact Vascular, Wayne, Pa) is purpose-built to repair postpercutaneous transluminal angioplasty (PTA) BTK dissections. A trial was conducted to investigate the safety and efficacy of the first-of-a-kind implantable BTK device to treat post-PTA dissections in the setting of critical limb ischemia.

METHODS

The present prospective, single-arm, multicenter study evaluated the Tack Endovascular System for treating post-PTA dissections in the mid/distal popliteal, tibial, and peroneal arteries. The primary safety endpoint was major adverse limb events (MALE) plus perioperative death (POD), assessed at 30 days after the index procedure. The primary efficacy endpoint was a composite of MALE at 6 months and POD. The unpowered secondary endpoint was primary patency at 6 months. With no available on-label comparator, the primary endpoints of the present trial were determined using objective performance goals from a systematic literature search. The secondary endpoints included Tacked segment patency and target limb salvage at 6 months. The 6-month results are reported.

RESULTS

Of the 233 patients enrolled, 117 (50.2%) had Rutherford class 5 and 78 (33.5%) had Rutherford class 4. A total of 341 post-PTA dissections were treated. Each patient received at least one Tack implant, and 100% of the dissections resolved according to the angiographic core laboratory findings. The primary safety and efficacy endpoints were both met. The rate of MALE plus POD at 30 days was 1.3% (3 of 228) and freedom from MALE at 6 months plus POD at 30 days was 95.6% (196 of 205). The 6-month Tacked segment patency was 82.1% (247 of 301) and target limb salvage was 98.5% (202 of 205). The Kaplan-Meier freedom from clinically driven target lesion revascularization and amputation-free survival at 6 months was 92.0% and 95.7%, respectively. Rutherford improvement was reported in 79.4% (158 of 199). Most (90 of 122; 73.8%) preexisting wounds had healed or were improving.

CONCLUSIONS

The Tack Endovascular System is safe and effective for treating post-PTA BTK dissections through 6 months, with favorable rates of MALE plus POD, patency, clinically driven target lesion revascularization, limb salvage, and wound healing.

Systematic review and meta-analysis of outcomes of lower extremity peripheral arterial interventions in patients with and without chronic kidney disease or end-stage renal disease

OBJECTIVE

Patients with chronic kidney disease (CKD) have a greater risk of peripheral arterial disease (PAD). Although individual studies have documented an association between CKD and/or end-stage renal disease (ESRD) and adverse outcomes in patients undergoing PAD interventions in an era of technological advances in peripheral revascularization, the magnitude of the effect size is unknown. Therefore, we performed a meta-analysis to compare the outcomes of PAD interventions for patients with CKD/ESRD with those patients with normal renal function, stratified by intervention type (endovascular vs surgical), reflecting contemporary practice.

METHODS

Five databases were analyzed from January 2000 to June 2019 for studies that had compared the outcomes of lower extremity PAD interventions for patients with CKD/ESRD vs normal renal function. We included both endovascular and open interventions, with an indication of either claudication or critical limb ischemia. We analyzed the pooled odds ratios (ORs) across studies with 95% confidence intervals (CIs) using a random effects model. Funnel plot and exclusion sensitivity analyses were used for bias assessment.

RESULTS

Seventeen observational studies with 13,140 patients were included. All included studies, except for two, had accounted for unmeasured confounding using either multivariable regression analysis or case-control matching. The maximum follow-up period was 114 months (range, 0.5-114 months). The incidence of target lesion revascularization (TLR) was greater in those with CKD/ESRD than in those with normal renal function (OR, 1.68; 95% CI, 1.25-2.27; P = .001). The incidence of major amputations (OR, 1.97; 95% CI, 1.37-2.83; P < .001) and long-term mortality (OR, 2.28; 95% CI, 1.45-3.58; P < .001) was greater in those with CKD/ESRD. The greater TLR rates with CKD/ESRD vs normal renal function were only seen with endovascular interventions, with no differences for surgical interventions. The differences in rates of major amputations and long-term mortality between the CKD/ESRD and normal renal function groups were statistically significant, regardless of the intervention type.

CONCLUSIONS

Patients with CKD/ESRD who have undergone lower extremity PAD interventions had worse outcomes than those of patients with normal renal function. When stratifying our results by intervention (endovascular vs open surgery), greater rates of TLR for CKD/ESRD were only seen with endovascular and not with open surgical approaches. Major amputations and all-cause mortality were greater in the CKD/ESRD group, irrespective of the indication. Evidence-based strategies to manage this at-risk population who require PAD interventions are essential.

Impact of Kidney Disease on Peripheral Arterial Interventions: A Systematic Review and Meta-Analysis

BACKGROUND

There are limited data on outcomes of patients undergoing peripheral arterial disease (PAD) interventions who have comorbid CKD/ESRD versus those who do not have such comorbid condition. We performed a systematic review and meta-analysis to analyze outcomes in this patient population.

METHODS

Five databases were searched for studies comparing outcomes of lower extremity PAD interventions for claudication and critical limb ischemia (CLI) in patients with CKD/ESRD versus non-CKD/non-ESRD from January 2000 to June 2019.

RESULTS

Our study included 16 observational studies with 44,138 patients. Mean follow-up was 48.9 ± 27.4 months. Major amputation was higher with CKD/ESRD compared with non-CKD/non-ESRD (odds ratio [OR 1.97] [95% confidence interval [CI] 1.39-2.80], p = 0.001). Higher major amputations with CKD/ESRD versus non-CKD/non-ESRD were only observed when indication for procedure was CLI (OR 2.27 [95% CI 1.53-3.36], p < 0.0001) but were similar for claudication (OR 1.15 [95% CI 0.53-2.49], p = 0.72). The risk of early mortality was high with CKD/ESRD patients undergoing PAD interventions compared with non-CKD/non-ESRD (OR 2.55 [95% CI 1.65-3.96], p < 0.0001), which when stratified based on indication, remained higher with CLI (OR 3.14 [95% CI 1.80-5.48], p < 0.0001) but was similar with claudication (OR 1.83 [95% CI 0.90-3.72], p = 0.1). Funnel plot of included studies showed moderate bias.

CONCLUSIONS

Patients undergoing lower extremity PAD interventions for CLI who also have comorbid CKD/ESRD have an increased risk of experiencing major amputations and early mortality. Randomized trials to understand outcomes of PAD interventions in this at-risk population are essential.

Far-infrared therapy improves ankle brachial index in hemodialysis patients with peripheral artery disease

Ankle brachial index (ABI) is a diagnostic tool for peripheral artery disease (PAD), which is an important issue in hemodialysis (HD) patients. We enrolled 198 maintenance HD patients in this study. PAD is defined as ABI ≤ 0.90. Only PAD patients received far-infrared (FIR) therapy using the WS TY101 FIR emitter for 40 min during each HD session, three times weekly for 6 months. The ABI was measured at the bilateral lower extremities for 4 times [pre-dialytic timing (0 min) and 40 min after the initiation of HD session at both day 0 and 6 months after the FIR therapy]. The primary outcome is the change in ABI. There were 51 out of 198 patients with PAD. In comparison with the period without FIR therapy in the 51 PAD patients, 6 months of FIR therapy significantly improved the ABI of the right/left side for 0 min (from 0.77 ± 0.19 to 0.81 ± 0.20, p = 0.027/0.79 ± 0.20 to 0.81 ± 0.17, p = 0.049), 40 min during HD (from 0.73 ± 0.23 to 0.83 ± 0.19, p < 0.001/from 0.77 ± 0.21 to 0.83 ± 0.18, p < 0.001), and the incremental change between 0 and 40 min (from - 0.04 ± 0.14 to 0.05 ± 0.13, p = 0.007/from - 0.05 ± 0.13 to 0.03 ± 0.11, p = 0.012), respectively. In conclusion, the application of FIR therapy for 40 min, three times weekly for 6 months, has improved the ABI of both lower extremities, thus providing a new strategy of PAD treatment in HD patients.

Predictive Parameters for Clinical Outcome in Patients with Critical Limb Ischemia Who Underwent Percutaneous Transluminal Angioplasty (PTA): A Systematic Review

Purpose

To identify possible risk factors in predicting clinical outcome in critical limb ischemia (CLI) patients undergoing percutaneous transluminal angioplasty (PTA).

Materials and Methods

PubMed and EMBASE were searched for studies analyzing CLI and clinical outcome after PTA from January 2006 to April 2017. Outcome measures were ulcer healing, amputation free survival (AFS)/limb salvage and overall survival. Data on predictive factors for ulcer healing, AFS/limb salvage and survival were extracted.

Results

Ten articles with a total of 2448 patients were included, all cohorts and based on prospective-designed databases. For ulcers, it seems that complete healing can be achieved in most of the patients within 1 year. No significant predictive factors were found. AFS/limb salvage: AFS rates for 1, 2 and 3 years ranged from 49.5 to 75.2%, 37 to 58% and 22 to 59%, respectively. Limb salvage rates for 1, 2 and 3 years ranged from 71 to 95%, 54 to 93.3% and 32 to 92.7%, respectively. All studies had different univariate and multivariate outcomes for predictive factors; however, age and diabetes were significant predictors in at least three studies. Survival: Survival rates for 1, 2 and 3 years ranged from 65.4 to 91.5%, 45.7 to 76% and 37.3 to 83.1%, respectively. Different predictive factors were found; however, age was found in 2 out of 5 studies reporting on predictive factors.

Conclusions

In several studies two factors, age and diabetes, were found as predictive factors for AFS/limb salvage and survival in patients with CLI undergoing PTA. Therefore, we believe that these factors should be taken into account in future research.

Level of Evidence

Level 2a.

Outcomes of Isolated Tibial Endovascular Intervention for Rest Pain in Patients on Dialysis

BACKGROUND

Tibial interventions for critical limb ischemia are frequent in patients with end-stage renal disease (ESRD) presenting with critical ischemia. The aim of this study was to examine impact of ESRD on the patient-centered outcomes following tibial endovascular Intervention for rest pain.

METHODS

A database of patients undergoing lower extremity endovascular interventions between 2006 and 2016 was retrospectively queried. Patients with rest pain (Rutherford 4) were identified. Patients with claudication (Rutherford 1 to 3) and tissue loss (Rutherford 5 and 6) were excluded. Patients were categorized by the presence or absence of ESRD. Patient-orientated outcomes of clinical efficacy (CE; absence of recurrent symptoms, maintenance of ambulation, and absence of major amputation), amputation-free survival (AFS; survival without major amputation), and freedom from major adverse limb events (MALEs; above ankle amputation of the index limb or major reintervention new bypass graft, jump/interposition graft revision) were evaluated.

RESULTS

A total of 829 patients (56% male, average age 59 years; 658 nonhemodialysis [non-HD] and 171 HD) underwent isolated tibial intervention in one leg for rest pain. Technical success was 99% with a median of 2 vessels treated per patient. There was no difference in the distribution of Trans-Atlantic Inter-Society Consensus I lesions, but both the modified Society for Vascular Surgery (SVS) runoff score and the pedal runoff score were worse in the HD group. The 30-day major adverse cardiac events and 30-day MALEs were equivalent in both groups. CE was 38 ± 9% and 19 ± 8% at 5 years for the non-HD and HD groups, respectively (P < 0.01). Overall, AFS was 45 ± 8% and 18 ± 9% at 5 years for the non-HD and HD groups, respectively (P < 0.01). Freedom from MALE was 41 ± 9% and 21 ± 8% at 5 years for the non-HD and HD groups, respectively (P < 0.01).

CONCLUSIONS

Patients with ESRD who present with rest pain have equivalent short-term outcomes to those not on dialysis but do not achieve long-term satisfactory CE and AFS after isolated tibial intervention for rest pain.