Li-Ming Wei

Runoff detected by magnetic resonance angiography as an indicator for better recanalization outcomes in below-the-knee chronic total occlusions in diabetic patients.

Purpose: To compare the feasibility and efficacy of recanalizing below-the-knee (BTK) chronic total occlusions (CTOs) between patients with good or poor distal runoff based on magnetic resonance angiography (MRA) scans. Methods: Two hundred long-segment BTK CTOs in 171 limbs of 113 diabetic patients (58 men; mean age 69.8±1.9 years) were divided into good distal runoff (GDR: 119 lesions, 98 limbs) or poor distal runoff groups (PDR: 81 lesions, 73 limbs) based on baseline MRA findings. After angioplasty, modified thrombolysis in myocardial ischemia (mTIMI) grades and ankle-brachial index (ABI) were used to assess immediate outcomes. Regularly scheduled duplex or MRA imaging was performed in follow-up. The restenosis and limb salvage rates were compared. Results: The success rates were 93.3% and 87.7% in the GDR and PDR groups, respectively (p=0.21); subintimal angioplasty was more common in the PDR group (93.0% vs. 63.1%, p<0.01). Completion angiography indicated an mTIMI grade 3 blood flow in 71.2% lesions in the GDR patients and in 52.1% in the PDR (p=0.01) group. Improvement in the ABI was greater in the GDR limbs (p<0.001 vs. PDR). Mean imaging follow-up was 10.8±6.9 months in the GDR group and 11.1±6.6 months in the PDR group. Kaplan-Meier analysis showed a better restenosis-free rate in the GDR group (80.6% vs. 61.7%; p=0.02) at 12 months and for lesions with mTIMI grade 3 flow (p<0.01). At 24 months, Kaplan-Meier analysis revealed a better limb salvage rate in the GDR group (84.2% vs. 54.6%; p=0.02). Conclusion: Distal runoff detected using MRA could be a predictor for successful intraluminal recanalization, better distal tissue perfusion, improved long-term patency, and better limb salvage for patients with BTK CTOs.

Infrainguinal Endovascular Recanalization: Risk Factors for Arterial Thromboembolic Occlusions and Efficacy of Percutaneous Aspiration Thrombectomy

PURPOSE To investigate factors predictive of thromboembolic occlusions and evaluate the efficacy of percutaneous aspiration thrombectomy (PAT) for infrainguinal thromboembolic occlusions in patients undergoing endovascular recanalization (EVR). MATERIALS AND METHODS In this single-center retrospective study, 23 patients who underwent PAT for thromboembolism during EVR and 237 patients who underwent successful EVR without thromboembolic occlusions (control group) were enrolled. Immediate posttreatment and follow-up outcomes between groups were compared. Multivariate analysis was performed to identify factors predictive of thromboembolic occlusions. Technical success of PAT was defined as achievement of < 30% residual stenosis and restoration of modified thrombolysis in myocardial infarction grade 3 flow. RESULTS The technical success rate was 95.7% in the PAT group. After intervention, ankle brachial index (ABI), restoration of blood flow, and improvement in dorsal/plantar arterial pulse score showed no significant differences between the PAT and control groups. During follow-up, no significant differences were observed between groups in improvement of sustained ABI and maximum walking distance, ulcer healing, restenosis/occlusion and limb salvage rates, and pain relief in patients with critical ischemia. Stenosis greater than 90% with lesion occlusion (odds ratio, 12.891; 95% confidence interval, 1.676-99.161; P = .014) and intraluminal angioplasty (odds ratio, 18.423; 95% confidence interval, 2.408-140.942; P = .005) were associated with a high incidence of thromboembolism. CONCLUSIONS Stenosis greater than 90% with lesion occlusion and intraluminal angioplasty may be factors predictive of thromboembolic occlusions. PAT is a safe and effective treatment for thromboembolism during infrainguinal arterial EVR.

Retrograde Transplantar Arch Angioplasty of Below-the-Knee Arterial Occlusions : Outcomes Compared to Anterograde Recanalization

RATIONALE AND OBJECTIVES To compare the clinical outcomes of retrograde transplantar arch angioplasty and conventional below-the-knee (BTK) anterograde recanalization. MATERIALS AND METHODS One hundred twelve limbs in 96 patients underwent attempt at antegrade tibial angioplasty. Among 27 technical failures, retrograde trans-dorsal or -planter percutaneous transluminal angioplasty was attempted in 22 limbs. Ankle-brachial index (ABI), thrombolysis in myocardial infarction (TIMI) flow grade, and dorsal/plantar arterial pulse score improvement were compared immediately after the procedures between patients received successful anterograde angioplasty (anterograde angioplasty group [AAG], 85 limbs in 71 patients) and retrograde angioplasty (retrograde angioplasty group [RAG], 22 limbs in 20 patients). Target vessel restenosis and limb salvage were observed during follow-up. RESULTS Primary technical success rate was 75.9% in the RAG (vs. 74.0% AAG, P > .05). ABI improved from 0.55 ± 0.21 to 0.93 ± 0.19 in the RAG (vs. 0.56 ± 0.14 to 0.89 ± 0.18 AAG, P > .05). TIMI flow grade demonstrated greater reperfusion of distal foot tissue in the RAG (2.3 ± 0.8 vs. 1.0 ± 0.8, P < .05). Primary patency rates at 12 and 24 months were 63.6% (14 of 22) and 45.5% (10 of 22) in the RAG and 52.9% (45 of 85) and 37.6% (32 of 85) in the AAG, respectively (P > .05). Kaplan-Meier analysis after 24 months found limb salvage rates of 93.8% in the RAG and 96.5% in the AAG (P > .05). CONCLUSIONS Retrograde transplantar arch angioplasty achieved better immediate blood flow and similar ABI improvement, primary patency rate, and limb salvage rate compared to conventional transtibial angioplasty for BTK occlusions. This could become a supplementary technique when anterograde angioplasty fails.

Morphological characteristics of chronic total occlusion: predictors of different strategies for long-segment femoral arterial occlusions

ObjectivesTo investigate morphological characteristics used to predict recanalisation strategies in long-segment (>10 cm) femoral chronic total occlusion (LSF-CTO) angioplasty.MethodsWe retrospectively evaluated a range of morphological CTA and DSA features in patients who underwent recanalisation of LSF-CTO. The stage of CTO was classified into early (3–12 months) and late (>12 months) according to estimated duration. Characteristics including stump morphology, lesion length and calcification, proximal side branches, collaterals circulation, runoff vessels and concomitant arterial occlusion were used as predictors, and multivariate logistic regression analysis was performed to identify variables associated with late-stage CTO and retrograde technique.ResultsA total of 119 patients with 137 CTOs in 137 limbs were enrolled. Overall, successful recanalisation was achieved in 122 CTOs (89.1%). Flush occlusion [odds ratio (OR) 2.958; 95% confidence interval (CI) 1.172–7.465; p = 0.022], large collateral (OR 2.778; 95% CI 1.201–6.427; p = 0.017) and TransAtlantic Inter-Society Consensus II class D (TASC D) lesion (OR 1.743; 95% CI 1.019–2.981; p = 0.042) were predictors for late-stage CTO. Flush occlusion (OR 75.278; 95% CI 10.664–531.384; p < 0.001) and large collateral (OR 23.213; 95% CI 3.236–166.523; p = 0.002) were associated with high likelihood for retrograde approach.ConclusionsFlush occlusion and large collateral were associated with a CTO at late-stage which may require retrograde recanalisation.Key points• CTO morphological characteristics help estimate lesion duration and optimise recanalisation strategies.• Flush occlusion and large collateral is associated with late-stage CTO and retrograde recanalisation.• Application of anterograde and retrograde recanalisation for long-segment femoral CTO is effective.The original version of this article unfortunately contained mistakes. The legends to Figs. 2–4 were incorrectly interchanged. The correct versions are given below. The original article has been corrected.

Silicone-covered biodegradable magnesium- stent insertion in the esophagus: a comparison with plastic stents

Background: We determined the feasibility of, and tissue response to silicone-covered biodegradable magnesium- and plastic-stent insertion into the esophagus in rabbits. Methods: The mechanical compression–recovery characteristics and degradation behaviors of the magnesium stent were investigated in vitro. A total of 45 rabbits were randomly divided into a magnesium- (n = 15) and a plastic- (n = 15) stent group, and underwent stent insertion into the lower third of the esophagus under fluoroscopic guidance; a control group (n = 15) did not undergo the intervention. Esophagography was performed at 1, 2, and 4 weeks. Five rabbits in each group were euthanized at each time point for histological examination. Results: Silicone-covered magnesium stents showed similar radial force to plastic stents (p > 0.05). The magnesium stents degraded rapidly in an acidic solution, but 90.2% ± 3.1% of the residual mass was maintained after a 2-week degradation in a solution with a pH of 4.0. All stent insertions were well tolerated. Magnesium stents migrated in six rabbits (one at 1 week, one at 2 weeks and four at 4 weeks), and plastic stents migrated in three rabbits (one at 2 weeks and two at 4 weeks; p > 0.05). Esophageal wall remodeling (thinner epithelial and smooth muscle layers) was similar in both stented groups (p > 0.05), and the esophagus wall was found to be significantly thinner in the stented groups than in the control group (p < 0.05). Esophageal injury and collagen deposition following stent insertion were similar and did not differ from the control group (p > 0.05). Conclusions: Esophageal silicone-covered magnesium stents provided reliable support for at least 2 weeks, with acceptable migration rates and without causing severe injury or tissue reaction compared with plastic stents.

Rendezvous technique for recanalization of long-segmental chronic total occlusion above the knee following unsuccessful standard angioplasty

Purpose To assess the technical feasibility and efficacy of the rendezvous technique, a type of subintimal retrograde wiring, for the treatment of long-segmental chronic total occlusions above the knee following unsuccessful standard angioplasty. Methods The rendezvous technique was attempted in eight limbs of eight patients with chronic total occlusions above the knee after standard angioplasty failed. The clinical symptoms and ankle-brachial index were compared before and after the procedure. At follow-up, pain relief, wound healing, limb salvage, and the presence of restenosis of the target vessels were evaluated. Results The rendezvous technique was performed successfully in seven patients (87.5%) and failed in one patient (12.5%). Foot pain improved in all seven patients who underwent successful treatment, with ankle-brachial indexes improving from 0.23 ± 0.13 before to 0.71 ± 0.09 after the procedure (P < 0.001). At the end of the follow-up period, the visual analogue scale improved from 6.86 ± 1.57 to 1.57 ± 1.27 (P < 0.001). Non-healing ulcers in three patients either healed (n = 2) or improved (n = 1). No major amputation was necessary. Kaplan–Meier analyses revealed that stenosis-free rate was 83.3% at six months and 41.7% at 12 months. Conclusion The rendezvous technique is a feasible and effective treatment for chronic total occlusions above the knee when standard angioplasty fails.

Predictors for Better Blood-Flow Restoration of Long-Segmental Below-the-Knee Chronic Total Occlusions after Endovascular Therapy in Diabetic Patients

Objective To prospectively investigate predictors for good restoration of blood flow of below-the-knee (BTK) chronic total occlusions (CTOs) after endovascular therapy in diabetes mellitus (DM) patients. Materials and Methods A total of 120 long-segmental (≥ 5 cm) BTK, CTOs in 81 patients who underwent recanalization were included in this study. After angioplasty, blood-flow restoration was assessed using modified thrombolysis in myocardial ischemia grades and classified as good flow (grade 3) and poor flow (grade 1/2). One hundred and six CTOs with successful recanalization were divided into a good flow group (GFG; n = 68) and poor flow group (PFG; n = 38). Multivariate logistic regression analyses were undertaken to determine independent predictors of blood-flow restoration. Receiver operating characteristic curves were constructed to determine the best cutoff value. The prevalence of target-lesion restenosis during follow-up was compared between two groups. Results Univariate analyses suggested that CTOs in GFG were characterized by lighter limb ischemia (p = 0.03), shorter course of ischemic symptoms (p < 0.01) and lesion length (p = 0.04), more frequent use of intraluminal angioplasty (p = 0.03), and higher runoff score (p < 0.01) than those in PFG. Multivariate regression analyses suggested that distal runoffs (p = 0.001; odds ratio [OR], 10.32; 95% confidence interval [CI]: 4.082–26.071) and lesion length (p < 0.001; OR, 1.26; 95% CI: 1.091–1.449) were independent predictors for good flow restoration. Kaplan-Meier analyses at 12 months showed a higher prevalence of non-restenosis in GFG (p < 0.01). Conclusion Distal runoffs and lesion length are independent predictors for good flow restoration for long-segmental BTK, CTOs in DM patients who receive endovascular therapy.

Percutaneous Aspiration Thrombectomy for Arterial Thromboembolism during Infrainguinal Endovascular Recanalization.

Objectives To evaluate the efficacy of percutaneous aspiration thrombectomy (PAT) for infrainguinal arterial thromboembolism in patients undergoing endovascular recanalization (EVR) and to investigate the predictors for thromboembolic complications. Materials and Methods In total, 23 patients (23 limbs) who underwent PAT for thromboembolism (PAT group, PG) during EVR and 237 patients (302 limbs) who underwent successful EVR without thromboembolic complications (control group, CG) were enrolled. Immediate post-operation and follow-up outcomes were compared between the two groups. Multivariate analysis was performed to identify the predictors of thromboembolic complications. Technical success of PAT was defined as achievement of <30% residual stenosis and restoration of mTIMI grade 3. Results The technical success rate was 95.7% in PG. After intervention, the ankle–brachial index (ABI), restoration of blood flow and improvement in dorsal/plantar arterial pulse score showed no significant differences between PG and CG. During follow-up in PG, a sustained ABI improvement was observed in 63.6% (70.9% in CG), an improvement in walking distance in 68.8% (79.9% in CG,), ulcer healing in 75.0% (71.7% in CG) and restenosis/occlusion in 31.8% (25.2% in CG). The limb salvage rate was 100% in PG (96.0% in CG), and pain relief was observed in 66.7% patients with critical limb ischaemia (81.6% in CG). Superficial femoral artery involvement [0.233; 95% confidence interval (CI), 0.108–0.461; P < 0.001], de-novo lesion occlusion (683.8; 95% CI, 36.5–12804.6; P < 0.001) and intraluminal angioplasty (118.4; 95% CI, 8.0–1758.0; P = 0.001) was associated with high incidence of thromboembolism. Conclusion PAT is a safe and effective treatment for thromboembolism during infrainguinal arterial EVR. SFA involvement, de-novo lesion occlusion and intraluminal angioplasty may be predictors of thromboembolic complications.