Validation of JCLIMB, SPINACH, and VQI Calculators for Prediction of Two Year Survival in Patients With Chronic Limb Threatening Ischaemia After Infra-Inguinal Surgical or Endovascular Revascularisation

OBJECTIVE

This study aimed to evaluate three survival prediction models: the JAPAN Critical Limb Ischaemia Database (JCLIMB), Surgical Reconstruction Versus Peripheral Intervention in Patients With Critical Limb Ischaemia (SPINACH), and Vascular Quality Initiative (VQI) calculators.

METHODS

Multicentre data of patients who underwent infrainguinal revascularisation for chronic limb threatening ischaemia between 2018 and 2021 were analysed retrospectively. The prediction models were validated using a calibration plot analysis with the intercept and slope. The discrimination was evaluated using area under the curve (AUC) analysis. The observed two year overall survival (OS) was evaluated by the Kaplan - Meier method. The two year OS predicted by each model at < 50%, 50 - 70%, and > 70% was defined as high, medium, and low risk, respectively.

RESULTS

A total of 491 patients who underwent infra-inguinal revascularisation were analysed. The rates of surgical revascularisation, endovascular therapy, and hybrid therapy were 26.5%, 70.1%, and 5.5%, respectively. The average age was 75.6 years, and the percentages of patients with diabetes mellitus and dialysis dependent end stage renal disease were 66.6% and 44.6%, respectively. The tissue loss rate was 85.7%. The intercept and slope were -0.13 and 1.18 for the JCLIMB, 0.11 and 0.82 for the SPINACH, and -0.15 and 1.10 for the VQI. The AUC for the two year OS of JCLIMB, SPINACH, and VQI were 0.758, 0.756, and 0.740, respectively. The observed two year OS rates of low, medium, and high risk using the JCLIMB calculator were 80.1%, 61.1%, and 28.5%, respectively (p < .001), using the SPINACH calculator were 81.0%, 57.0%, and 38.1%, respectively (p < .001), and using the VQI calculator were 77.8%, 45.8%, and 49.6%, respectively (p < .001).

CONCLUSION

The JCLIMB, SPINACH, and VQI survival calculation models were useful, although the OS predicted by the VQI model appeared to be lower than the observed OS.

Global Limb Anatomic Staging System Inframalleolar Modifier Predicts Limb Salvage and Wound Healing in Patients with Chronic Limb Threatening Ischaemia Undergoing Endovascular Infrainguinal Revascularisation

OBJECTIVE

This study aimed to analyse the influence of the Global Anatomic Staging System (GLASS) and inframalleolar (IM) disease on the treatment outcomes of patients with chronic limb threatening ischaemia (CLTI) who undergo endovascular treatment (EVT) METHODS: Data of patients who underwent infrainguinal endovascular therapy (EVT) for CLTI between 2015 and 2019 at two centres were analysed retrospectively. The endpoints were major amputation, major adverse limb events (MALE), and wound healing.

RESULTS

Overall, 276 patients and 340 limbs were analysed. The number of revascularisations for an infrapopliteal lesion was 48 (70.6%), 63 (63.0%), and 142 (82.6%) in the GLASS I, GLASS II, and GLASS III stages, respectively (p < .001). There was no statistically significant difference in limb salvage among the GLASS stages (p = .78). The limb salvage rates at one year were 94.6%, 88.0%, and 70.0% in the IM P0 P1, and P2 groups, respectively (p < .001). Multivariable analysis showed that Wound, Ischemia, and foot Infection (WIfI) stage, and IM grade were risk factors for major amputation. The freedom from MALE rates at two years were 60.5%, 45.3%, and 41.1% in the GLASS I, II, and III stages, respectively (p = .003) and 64.1%, 43.5%, and 18.4% in the IM P0, P1, and P2 groups, respectively (p < .001). Multivariable analysis demonstrated that WIfI stage, GLASS stage, IM grade, and infrapopliteal revascularisation were risk factors for MALE. There was no significant difference in wound healing among GLASS I - III (p = .75). The wound healing rates at 365 days were 78.6%, 68.6%, and 42.0% in the IM P0, P1, and P2 groups, respectively (p = .065). Multivariable analysis showed that WIfI stage and IM P2 were risk factors for incomplete wound healing.

CONCLUSION

GLASS IM was associated with major amputation, MALE, and wound healing, while GLASS stage was associated with only MALE.

Does the Global Limb Anatomic Staging System Inframalleolar Modifier Influence Long Term Outcomes of Chronic Limb Threatening Ischaemia after Distal Bypass?

OBJECTIVE

The purpose of this study was to evaluate the influence of inframalleolar disease (Global Limb Anatomic Staging System Inframalleolar [GLASS IM] modifier) on long term outcomes of patients with chronic limb threatening ischaemia (CLTI) after distal bypass.

METHODS

Patients who underwent distal bypass for CLTI from January 2012 to December 2019 at a single centre were reviewed retrospectively. Comparisons including baseline characteristics, procedural details, and long term outcomes were made between patients with an intact pedal arch (GLASS IM modifier P0), an absent or severely diseased pedal arch (P1), and no target artery crossing the ankle into the foot (P2), diagnosed by pre- and intra-operative high quality angiography. The primary endpoint was limb salvage. The secondary endpoints were graft patency and wound healing.

RESULTS

A total of 254 distal bypasses were performed in 206 patients (139 males; median age, 76 years). The GLASS IM modifier was P0 in 80 (32%) limbs, P1 in 127 (50%), and P2 in 47 (18%). During the follow up period, 22 limbs (9%) required major amputation. The limb salvage rates at three years in P0, P1, and P2 cases were 94%, 89%, and 93%, respectively, with no significant differences among the modifiers. The primary patencies at three years in P0, P1, and P2 cases were 49%, 38% and 24%, respectively. The primary patency in P2 cases was significantly lower than that in P0 cases (p < .050). The respective wound healing rates at 12 months were 97%, 93%, and 79%, and again the wound healing rate in P2 cases was significantly lower than those in other cases (p < .050).

CONCLUSION

Long term outcomes including patency, limb salvage, and wound healing after distal bypass for CLTI patients with an infrapopliteal lesion were acceptable in cases in each GLASS IM modifier.

Comparison of Long Term Outcomes After Endovascular Treatment Versus Bypass Surgery in Chronic Limb Threatening Ischaemia Patients with Long Femoropopliteal Lesions

OBJECTIVE

There are currently two treatments available for patients with chronic limb threatening ischaemia (CLTI): open surgical bypass (OSB) and percutaneous transluminal angioplasty with/without stenting (PTA/S). The aim of this study was to compare short and long term outcomes between PTA/S and OSB in CLTI patients with long (GLASS grade III and IV) femoropopliteal disease.

METHODS

This was a two centre retrospective study including all consecutive patients with CLTI undergoing first time lower extremity intervention at two distinct vascular surgical centres. Between 1 January 2012 and 1 January 2018, 1 545 CLTI consecutive limbs were treated for femoropopliteal GLASS grade III and IV lesions at two vascular surgical centres. Using covariables from baseline and angiographic characteristics, a propensity score was calculated for each limb. Thus, comparable patient cohorts (235 in PTA/S and 235 in OSB group) were identified for further analysis. The primary outcomes were freedom from re-intervention in the treated extremity and major amputation. Secondary outcomes were all hospital complications among the two patient groups.

RESULTS

Total overall complication rates were significantly higher in the OSB group (20.42% vs. 5.96%, p < .001), especially wound infection/seroma rate that required prolonged hospitalisation and further treatment (7.65% vs. 0%, p < .001). After the median follow up of 61 months, re-intervention rates were significantly higher in the PTA/S group (log rank test, 44.68% vs. 29.79%, p = .002), but there was no significant difference in terms of major amputation rates between the two group of patients (log rank test, PTA/S 27.23% vs. OSB 22.13%, p = .17).

CONCLUSION

Bypass surgery seems to be superior to PTA/S for GLASS grade III and IV femoropopliteal lesions in patients with CLTI in terms of long term re-intervention rates, but with considerably higher rates of post-operative complications. A larger cohort of patients in currently ongoing randomised trials, as well as prospective cohort studies are necessary to confirm these findings.

Midterm Outcomes of Common Femoral Endarterectomy Combined with Inflow and Outflow Endovascular Treatment for Chronic Limb Threatening Ischaemia

OBJECTIVE

To assess mid term outcomes of common femoral endarterectomy combined with an inflow and outflow endovascular revascularisation procedure in patients with chronic limb threatening ischaemia (CLTI).

METHODS

This was a prospective study. All patients who, for the first time, underwent planned one stage hybrid common femoral artery (CFA) endarterectomy combined with an inflow and/or outflow endovascular revascularisation procedure to achieve limb salvage in patients with CLTI due to multilevel disease were included between January 2015 and May 2017. Demographics, and clinical and lesion characteristics for each patient were reported. The primary outcome was primary patency. Secondary outcomes were technical success, peri-operative morbidity and mortality, assisted primary patency, secondary patency, clinically driven target lesion revascularisation and amputation free survival.

RESULTS

Three groups were created according to the endovascular treatment zone: group 1 (inflow, n = 60); group 2 (outflow, n = 46); and group 3 (combined inflow and outflow, n = 53). CFA endarterectomy was a fixed step in all cases. The overall technical success was 98%. The peri-operative complication rate was 14% and the mortality rate was 2%. Patients in group 3 demonstrated a significantly lower primary patency rate (53.9% ± 7.1%; p < .001) at 24 months but improved secondary patency rate of (94.0% ± 3.4%). Based on the outcomes of the Cox regression multivariable analysis, lesion length (hazard ratio [HR] 1.10, 95% confidence interval [CI] 1.06-1.14; p < .001), chronic total occlusion (CTO) (HR 0.50, 95% CI 0.25-0.98; p = .046), peripheral artery calcium scoring system (PACSS) grade 4 (HR 2.44, 95% CI 1.27-4.68; p = .008), incomplete revascularisation (HR 3.32, 95% CI 1.64-6.73; p = .001), and dyslipidaemia (HR 0.50, 95% CI 0.27-0.93; p = .031) were the only significant independent predictors of loss of primary patency.

CONCLUSION

Common femoral endarterectomy combined with an inflow and outflow endovascular revascularisation procedure in patients with CLTI is safe, with acceptable patency rates, despite the need for secondary interventions. Dyslipidaemia, lesion length, CTO, PACSS grade 4, and incomplete revascularisation are independent predictors of primary patency loss. The current study analysis supports the recommendation to stage the procedure based on patient risk and degree of limb threat.