Clinical Outcomes of Patients With Cholesterol Crystal Embolism Accompanied by Lower Extremity Wound.

Cholesterol crystal embolism (CCE) accompanied by a lower extremity wound is occasionally difficult to differentiate from chronic limb-threatening ischemia (CLTI) and treat. The present multi-center retrospective observational study investigated the clinical characteristics and prognosis of CCE with lower extremity wounds. Consecutive patients (n = 58) clinically diagnosed as CCE with lower extremity wounds between April 2010 and December 2019 were studied. CCE was diagnosed using histological findings, foot condition, renal impairment, and eosinophilia. The primary outcome was 1-year wound healing rate. Patients with CCE were compared with 1309 patients diagnosed with CLTI with tissue loss during the same study period. The CCE group had a significantly more severe Wound, Ischemia, and foot Infection (WIfI) classification compared with the CLTI group. After Kaplan-Meier analysis, the CCE group had a similar 1-year wound healing (55.1 vs 58.3%, P = .096) as the CLTI group. In multivariate stratified Cox regression analysis by WIfI stages, CCE was significantly associated with poor wound healing compared with CLTI [hazard ratio .36 (95% confidence interval .21-.62)]. In conclusion, among the similar WIfI clinical stages, wound healing was significantly worse in the CCE group than in the CLTI group.

The Effect of Clinical Frailty on Wound Healing in Patients With Chronic Limb-Threatening Ischemia.

PURPOSE: Clinical frailty increases the risk of adverse outcomes in older people. Patients with Chronic limb-threatening ischemia (CLTI) also had several clinical frailties. The aim of this study was to investigate the correlation between clinical frailty scales (CFS) at discharge and wound healing rate in patients with tissue loss. METHODS: A total of 510 limbs in 431 CLTI patients who were undergone endovascular treatment (EVT) from January 2013 to November 2018 were enrolled in this study. Patients were categorized into 4-groups based on the CFS stages: CFS 1 to 4 (well), CFS 5 (mild), CFS 6 (moderate) and CFS ≥7 (severe). And the change in patient's activities during hospitalize was classified into 3 groups based on CFS; improve, stable, worse. Primary endpoint was correlation between CFS at discharge and wound healing rate. Secondary endpoint was relationship between the changes in patient's activities and wound healing rate. RESULTS: A total of 365 limbs were obtained complete wound healing during this study period. Patient distribution into the 4 CFS groups was as follows: 13.3% (well), 21.8% (mild), 25.3% (moderate) and 39.6% (severe). Wound healing rate in severe CFS group was significantly lower than that in other CFS groups (p<0.0001). Wound healing rate in the patients who achieved improvement of activity was significantly higher than that in the other groups (p=0.008). CONCLUSIONS: CFS might be useful for risk stratification in patients with tissue loss. And improvement of activity during hospitalization might lead to increase the wound healing rate. CLINICAL IMPACT: Although the association between clinical frailty and prognosis outcome of Chronic limb-threatening ischemia (CLTI) has been reported, the effect of clinical frailty on wound healing remains unclear. Clinical frailty scale is independently associated with wound healing and might be useful for risk stratification in patients with tissue loss. Improvement of activity during hospitalization might lead to increase the wound healing rate.

Novel combination therapy of pedal arch angioplasty and dual distal bypass as an alternative treatment option for vasculitis in patients with chronic limb-threatening ischemia.

A 68-year-old man with chronic limb-threatening ischemia caused by atypical vasculitis was successfully treated by the combination of pedal arch angioplasty and dual distal bypass. Angioplasty alone failed; therefore, we performed pedal arch angioplasty followed by distal bypass revascularized to the newly created dorsalis pedis artery and posterior tibial artery anastomosis sites. Restenosis occurred twice, and both cases were successfully treated by immediate angioplasty. Both branches of the graft remained patent for >2.5 years, and the wound healed completely. This unique combination of techniques can provide favorable results for selected patients with chronic limb-threatening ischemia.

Intravascular ultrasound-based decision tree model for the optimal endovascular treatment strategy selection of femoropopliteal artery disease-results from the ONION Study.

BACKGROUND: The role of catheter-based imaging in peripheral interventions for lower extremity artery disease (LEAD) has increased with percutaneous interventions. To clarify the relation between intravascular ultrasound (IVUS) information and procedure selection strategy for endovascular treatment therapy (EVT) of the femoropopliteal artery in the real-world clinical settings wherein new endovascular technologies (NETs), including drug-coated balloon (DCB), drug-eluting stent (DES), and covered stent-graft (CS). Our retrospective multicenter analysis examined symptomatic 970 patients treated by EVT for de novo femoropopliteal lesions with IVUS guidance. The decision tree analysis was performed retrospectively to determine the association of IVUS and angiography parameters with the strategy selection of endovascular procedures. We divided the study population according to the developed tree, and identified the most popular strategy selection in each subgroup. We finally examined whether the restenosis risk would be different among respective subgroups of the tree. RESULTS: During the study periods, plain old balloon angioplasty, DCB, and bare nitinol stent were most frequently selected (25.3%, 23.9%, and 23.8%, respectively). The drug-eluting stent (DES), covered stent (CS), and spot stent strategies were used in 7.3%, 11.5%, and 8.1%. NETs had the lowest restenosis risk in the overall population. The decision tree had a depth of six branches and divided the patients into 11 subgroups by IVUS and angiography parameters. The restenosis rate was similarly low among these 11 subgroups when the most popular NET in each subgroup was selected (P = 0.94). CONCLUSIONS: The use of IVUS data along with angiography data would standardize the selection of endovascular procedures and can improve patency outcomes if NETs are used properly.

Impact of Peak Systolic Velocity Ratio after Drug-Coated Balloon for Femoropopliteal Disease: Three-Month Serial Observation Vessel Echo Study.

AIM: No flow-limiting dissection after drug-coated balloon (DCB) treatment for femoropopliteal (FP) lesions is considered as one of the endpoints, but it has not investigated the difference between each vessel dissection. This study aimed to clarify whether there is a difference between no dissection and type C dissection without flow-limiting dissection for 3 months by peak systolic velocity ratio (PSVR) based on duplex ultrasonography. METHODS: Between February 2020 and April 2021, 44 consecutive de novo FP diseases that underwent endovascular therapy (EVT) with DCB were enrolled in this study. 65.9% of the patients had intermittent claudication, and mean lesion lengths were 194±107 mm. The chronic total occlusion was 38.6%. After DCB treatment, vessel dissection pattern was categorized by angiography. The minimum lumen area (MLA) identified by intravascular ultrasound was serially evaluated with PSVRs at 1 day, 1 month, and 3 months after EVT. RESULT: All lesions were treated with DCB without provisional stents. The vessel dissection pattern after DCB treatment showed that types D, E, and F were not observed, 9% were no dissection, 27% were type A, 32% were type B, and 32% were type C. In all cases, the PSVR values of MLA site were less than 2.6 at 3 months, and there were no significant differences between no dissection and type C dissection. CONCLUSION: Up to dissection pattern "C" is considered acceptable as one of the endpoints to determine the need for provisional stenting after DCB treatment.

The impact of plaque morphology in patients with peripheral artery disease on vessel dissection: an intravascular ultrasound observational study.

Drug-coated balloon (DCB) is now available for endovascular treatment (EVT) of superficial femoral arteries (SFA). Although it has been reported that severe vessel dissection after balloon angioplasty was risk of restenosis, it is difficult to predict the vessel dissection patterns before balloon angioplasty. We investigated the correlation between plaque morphology and vessel dissection pattern after balloon angioplasty using the intravascular ultrasound (IVUS). A total of 73 de novo SFA lesions were enrolled in this study. IVUS examinations were measured at the minimum lumen area in the control angiogram. Plaque morphology, minimum lumen area (MLA) and vessel diameter at the same point were evaluated before and after the initial balloon angioplasty. Vessel dissection patterns after the initial balloon angioplasty were classified into 7 types (A to F). There were no severe dissection patterns which were more than type D dissection in this study. All patients were treated with DCB without any bailout stenting. No dissection was found in 35.6% (26/73). Type A, B and C dissections were seen in 17.8% (13/73), 40% (27/73) and 9.6% (7/73), respectively. Although there were no relations between plaque morphology and vessel dissection patterns (p = 0.547), the MLA with dissection was larger than that without dissection (5.78 mm2 versus 4.63 mm2, p = 0.032). Although the dissection patterns could not be predicted in non-severe (Non or A to C) dissection, our result might suggest that IVUS image has the potential to reduce severe dissection.

Roles of Angioplasty With Drug-Coated Balloon for Chronic Ischemia in Wound Healing.

PURPOSE: Clinical trials have demonstrated sustained benefits of drug-coated balloon (DCB) angioplasty compared with noncoated balloon angioplasty in symptomatic peripheral artery disease (PAD) presenting with femoropopliteal (FP) artery disease. However, there is still controversy whether particulate embolization caused by crystalline paclitaxel, the so-called "downstream effect," is adversely associated with clinical outcomes after use of FP DCB among chronic limb-threatening ischemia (CLTI) patients. The current RADISH (Roles of Angioplasty with Drug-coated balloon for chronic ISchemia in wound Healing) study investigated wound healing following DCB therapy vs non-DCB therapy for real-world CLTI patients presenting with FP lesions. MATERIALS AND METHODS: This multicenter, retrospective study analyzed 927 patients with CLTI (mean age, 76±10 years; male, 57.8%; diabetes mellitus, 64.5%; dialysis, 50.7%) presenting with FP lesions and treated endovascularly via DCB (138 patients) vs non-DCB therapy (789 patients) between April 2014 and March 2019. The primary outcome measure was 1-year wound healing, while the secondary outcome measure was 1-year primary patency. Clinically-driven target lesion revascularization (CD-TLR), limb salvage and overall survival were also analyzed by using propensity score matching analysis. RESULTS: The propensity score matching extracted 111 pairs (as many patients in the DCB group and 629 patients in the non-DCB group). The 1-year cumulative incidence of wound healing (95% CI) was 74.4% (62.6% to 82.5%) in the DCB group and 71.9% (60.4% to 80.1%) in the non-DCB group, with no significant intergroup difference (p=0.93). The DCB group had a higher rate of primary patency (p=0.002) and freedom from CD-TLR (p=0.010) than the non-DCB group, whereas there was no significant intergroup difference in limb salvage (p=0.21) or overall survival (p=0.93). CONCLUSION: The current analysis of data from the RADISH study demonstrated that DCB therapy did not lead to delayed wound healing and reduced restenosis rate in CLTI patients presenting FP lesions. From this results, DCB therapy would be a reasonable treatment option for CLTI patients.

Mechanisms of gradual pressure drop in angiographically normal left anterior descending and right coronary artery: Insights from wave intensity analysis.

BACKGROUND: This study evaluated the mechanism of decline in coronary pressure from the proximal to the distal part of the coronary arteries in the left anterior descending (LAD) versus the right coronary artery (RCA) from the insight of coronary hemodynamics using wave intensity analysis (WIA). METHODS: Twelve patients with angiographically normal LAD and RCA were prospectively enrolled. Distal coronary pressure, mean aortic pressure, and average peak velocity were measured at 4 different positions: 9, 6, 3, and 0 cm distal from each coronary ostium. RESULTS: The distal-to-proximal coronary pressure ratio during maximum hyperemia gradually decreased in proportion to the distance from the ostium (0.92±0.03 and 0.98±0.03 at 9 cm distal to the LAD and RCA ostium). WIA showed the dominant forward-traveling compression wave gradually decreased and the backward-traveling suction wave gradually decreased in proportion to the decrease in coronary pressure through the length of the non-diseased LAD but not the RCA. CONCLUSIONS: The pushing wave and suction wave intensities on WIA were diminished in proportion to the distance from the ostium of the LAD despite the wave intensity not changing across the length of the RCA, which may lead to gradual intracoronary pressure drop in the angiographically normal LAD.

Feasibility and Safety of the Direct Occluded Vessel Puncture Technique as a New Access Site for Complex Peripheral Artery Occlusive Disease.

AIM: This study aims to describe the feasibility and safety of direct occluded vessel puncture as a new access site for complex peripheral artery occlusive disease. METHODS: Eleven consecutive patients with symptomatic peripheral artery disease underwent endovascular therapy using the direct occluded vessel puncture technique. The occluded vessel was punctured using a dedicated 20 G needle and the Hi-Torque Command 18 ST guidewire under duplex echo or fluoroscopic guidance, and a 6 Fr sheath was then inserted. Hemostasis was achieved with the Exoseal® Vascular Closure Device. RESULTS: Direct occluded vessel puncture was achieved in 10 of 11 cases (90.9%), and procedural success was achieved in all cases. There were no in-hospital deaths or any complications, including bleeding, pseudoaneurysms, thrombosis, or surgical conversion. CONCLUSION: The direct occluded vessel puncture technique using a 20 G needle and the Hi-Torque Command 18 ST is feasible and safe. This technique may also be used as an alternative option when there are no appropriate approach sites.

Effect of Target Lesion Revascularization on Restenosis Lesions of the Superficial Femoral Artery without Recurred Symptoms after Endovascular Therapy.

AIM: This study aims to elucidate the effects of early application of target lesion revascularization (TLR) to restenosis lesions of the superficial femoral artery (SFA) without recurrence of symptoms. Despite recent improvements in endovascular therapy (EVT) for the SFA, restenosis remains to be a problem. However, restenosis is not always associated with the recurrence of limb symptoms. Although early application of TLR is not generally approved for restenosis lesions of the SFA without recurred symptoms, it is expected to contribute to long-term patency and other favorable outcomes. Nonetheless, its effectiveness remains to be determined. METHODS: We retrospectively analyzed 616 patients who developed restenosis after undergoing femoro-popliteal EVT for claudication (Rutherford category 1 to 3) due to de novo femoro-popliteal lesions between January 2010 and December 2016 at 11 centers in Japan. Recurred symptoms were defined as symptoms of the same or higher Rutherford categories than those immediately before the initial EVT. RESULTS: Of the patients, 291 (47 %) lacked recurred symptoms; 69 (24 %) underwent TLR for restenosis. After propensity matching, the risk of occlusion was determined to be not significantly different between the TLR and observation groups; the 3-year occlusion-free rate was 68 % and 62 %, respectively (P=0.84). The risk of recurring symptoms, critical limb ischemia, and all-cause death was also found to be comparable between groups. The incidence of target vessel revascularization was significantly higher in the TLR than in the observation group (1.55 [95 % confidence interval: 1.25-1.93] vs. 0.59 [0.41-0.85] per 3 person-years). CONCLUSIONS: In patients with SFA restenosis without recurred symptoms, early application of TLR showed no advantages.

Assessment of Microvasculature After Intervention as a Predictor of Wound Healing in Patients With Tissue Loss.

OBJECTIVES: This study investigated the correlation between vascular flow reserve (VFR) values and wound healing rate in patients with critical limb ischemia. BACKGROUND: Peripheral VFR may be useful for predicting complete wound healing after endovascular therapy (EVT). However, published reports included small numbers of patients from single centers and long-term outcomes remain unknown. METHODS: This was a prospective multicenter study that consecutively enrolled 104 patients (115 limbs) who received EVT for ischemic ulcerations. All lesions were treated with conventional balloon angioplasty. After EVT, VFR was measured using a pressure/temperature guidewire. The study endpoints were correlation between VFR values and wound healing rate at 3 months and 1 year. RESULTS: The median VFR was 2.9. A total of 110 and 104 limbs completed the 3-month and 1-year follow-up, respectively. The 3-month and 1-year wound healing rates were 49% and 76%, respectively. VFR was significantly associated with the 3-month and 1-year wound healing (p < 0.001 for both). The crude hazard ratios of VFR (per 2-fold increase) for the 3-month and 1-year wound healing were 2.6 (1.7 to 3.9) and 2.9 (2.0 to 4.2), respectively. The estimated median time to wound healing was 5.0 (3.2 to 7.2) months, 3.3 (2.8 to 4.9) months, and 2.5 (2.0 to 3.0) months, when the VFR value was 2.4, 2.9, and 3.9, respectively. CONCLUSIONS: Post-procedure VFR is significantly associated with wound healing. VFR, measured in the catheterization laboratory, is useful in clinical risk stratification for patients with critical limb ischemia after EVT. (Predictor of Wound Healing in Patients with Critical Limb Ischemia-Multicenter Prospective Study; UMIN000012746).

Impact of IVUS-Derived Vessel Size on Midterm Outcomes After Stent Implantation in Femoropopliteal Lesions.

Purpose: To identify intravascular ultrasound (IVUS) findings that predict midterm stent patency in femoropopliteal (FP) lesions. Materials and Methods: A retrospective analysis was undertaken of 335 de novo FP lesions in 274 consecutive patients (mean age 72.4±8.2 years; 210 men) who had IVUS assessment before and after successful stent implantation. The mean lesion length was 13.2±9.8 cm. The primary outcome was primary patency at 24 months, defined as freedom from major adverse limb event (MALE) and in-stent restenosis (ISR). MALE was defined as major amputation or any target lesion revascularization (TLR). ISR was defined by a peak systolic velocity ratio >2.4 by duplex ultrasonography. Logistic regression analyses were performed to identify independent predictors of stent patency at 24 months; the results are presented as the odds ratio (OR) and 95% confidence interval (CI). Receiver operator characteristic (ROC) curve analysis was performed to determine the optimal threshold for prediction of stent patency at 24 months. Results: Over the 24-month follow-up, 18 (7%) patients died and 43 (15%) of 286 lesions were responsible for MALE (42 TLRs and 1 major amputation). Primary patency was estimated at 82.5% (95% CI 78.1% to 86.9%) at 12 months and 73.2% (95% CI 67.9% to 78.5%) at 24 months. Multivariable analysis revealed that longer lesion length (OR 0.89, 95% CI 0.82 to 0.97, p<0.01) was an independent predictor of declining patency, while cilostazol use (OR 3.45, 95% CI 1.10 to 10.78, p=0.03) and increasing distal reference external elastic membrane (EEM) area (OR 1.18, 95% CI 1.02 to 1.37, p=0.03) were associated with midterm stent patency. ROC curve analysis identified a distal reference EEM area of 29.0 mm2 as the optimal cut-point for prediction of 24-month stent patency (area under the ROC curve 0.764). Kaplan-Meier estimates of 24-month primary patency were 83.7% (95% CI 78.3% to 89.2%) in lesions with a distal EEM area >29.0 mm2 vs 53.1% (95% CI 42.9% to 63.3%) in those with a distal EEM area ≤29.0 mm2 (p<0.001). Conclusion: In FP lesions with a larger distal vessel area estimated with IVUS, stent implantation can be considered as a reasonable treatment option, with the likelihood of acceptable midterm results.

Distribution of pressure gradients along the left anterior descending artery in patients with angiographically normal arteries.

OBJECTIVES: This study tested the hypothesis that there is no decline of coronary pressure from the proximal to the distal left anterior descending coronary artery (LAD) of humans and swine. BACKGROUND: In the daily clinical practice, the fractional flow reserve (FFR) in the LAD is frequently lower than that in the other arteries in the presence of a similar degree of stenosis. METHODS: Twenty-six patients with angiographically normal LAD were prospectively enrolled. The coronary pressure ratio (mean distal/proximal coronary pressures at hyperemia) was measured at five different positions: 12, 10, 7, and 5 cm distal from the LAD ostium, and at the ostium of the LAD. The coronary pressure measurement was further investigated in a swine model without atherosclerosis. RESULTS: The coronary pressure ratio during maximum hyperemia gradually decreased in proportion to the distance from the ostium (average: 0.85 ± 0.06 at 12 cm distal to the ostium). This finding was confirmed in swine model. The degree of the coronary pressure decrease during maximum hyperemia was similar in patients with and without evidence of minor plaque on intravascular ultrasound, however it was strongly associated with the amount of myocardium mass in the territory of the LAD. CONCLUSIONS: Intracoronary pressure gradually decreases in proportion to the distance from the ostium in the LAD of humans and swine, regardless of the presence of minor atherosclerotic plaques. The degradation degree of the coronary pressure ratio during maximum hyperemia is enlarged in the presence of larger amount of myocardium mass in the territory of the LAD.

IVUS Assessment of the Crossing Pathway of an Intraluminal Reentry Device Used in the Primary Treatment of Infrainguinal Chronic Total Occlusions.

Purpose: To examine with intravascular ultrasound (IVUS) the crossing pathways of the TruePath reentry device during primary antegrade recanalization of infrainguinal chronic total occlusions (CTOs). Methods: Between July 2017 and September 2018, a prospective multicenter study enrolled 143 consecutive patients (mean age 75±9 years; 101 men) with 146 CTOs treated in an antegrade approach using the TruePath reentry device with IVUS assessment of the crossing pathway in successful cases. Outcome measures were complete success (reentry device reached the distal true lumen), assisted success (reentry device use followed by a conventional guidewire to reach the distal true lumen), reentry device crossing route by IVUS assessment, and procedure- and device-related complications. Regression analyses were employed to identify any relevant associations between baseline patient variables and the outcome measures; results are presented as the odds ratio (ORs) and 95% confidence interval (CI). Results: Complete success was achieved in 82 (56.2%) lesions; any success (complete plus assisted) was documented in 117 (80.1%) lesions. Four (3%) perioperative device-related complications were observed. The crossing route was intraplaque for most of the total crossing distance in both complete success cases (95.3%±13.2%) and any success cases (94.8%±14.4%), with relatively short subintimal (3.6%±10.2% and 4.2%±11.2%, respectively) or intramedial (1.2%±5.8% and 1.0%±5.4%, respectively) crossing. CTO length was a significant risk factor for not achieving complete success (OR 1.74, 95% CI 1.13 to 2.68, p=0.012), and a history of failed revascularization was associated with not achieving any success (OR 6.40, 95% CI 1.28 to 28.9, p=0.038). Conclusion: The intraplaque route was the primary pathway taken by the TruePath reentry device as it crossed infrainguinal CTOs. Crossing rates were acceptable, with few device-related complications. However, a longer CTO length and a failed revascularization history negatively affected the success rate.

Vascular response to paclitaxel-eluting nitinol self-expanding stent in superficial femoral artery lesions: post-implantation angioscopic findings from the SHIMEJI trial (Suppression of vascular wall Healing after IMplantation of drug Eluting peripheral stent in Japanese patients with the Infra inguinal lesion: serial angioscopic observation).

The aim of this study was to elucidate the vascular responses to paclitaxel-eluting stent (Zilver PTX stent) in superficial femoral artery lesion at different elapsed times using angioscopy. Patients who received Zilver PTX stent implantation from five centers were enrolled. We performed angioscopic examinations at 2, 6, and 12 months after implantation and evaluated neointimal coverage (NIC) grade, intra-stent thrombus (IS-Th) grade, and presence of yellow plaque. NIC grade 0 was defined as stent struts exposed; grade 1, struts transparently visible although covered; grade 2, struts embedded in the neointima, but translucent; and grade 3, struts fully embedded and invisible. IS-Th was graded as follows: grade 0 (none), 1 (focal), and 2 (diffusely spread). Angioscopic follow-up evaluation was performed at 2 months (25 patients, 42 lesions), 6 months (18 patients, 23 stents), and 12 months (14 patients, 24 stents) after stent implantation. Dominant NIC grade significantly increased over time; however, 16.3% of the cases had NIC grade 1 or 2 at 12 months. IS-Th grade decreased; however IS-Th and yellow plaque were persistently observed in 62.5% and 83.3% cases, respectively, at 12 months. An ongoing healing response was observed at 12 months after implantation; however, thrombogenic findings were noted. Prolonged dual antiplatelet therapy could potentially enhance the clinical utility of Zilver PTX.

Lumen Gain After Endovascular Therapy in Calcified Superficial Femoral Artery Occlusive Disease Assessed by Intravascular Ultrasound (CODE Study).

PURPOSE: To assess calcium patterns in superficial femoral artery (SFA) disease before and after balloon angioplasty ± stent implantation using fluoroscopy, angiography, and intravascular ultrasound (IVUS) imaging and then correlate calcification severity and midterm clinical outcomes. MATERIALS AND METHODS: A multicenter investigation was carried out to retrospectively review 130 symptomatic patients (mean age 73.2±8.4 years; 86 men) with de novo SFA lesions who had successfully undergone endovascular therapy (EVT) at 7 centers between January and October 2015. The primary outcome was lumen gain measured as minimum lumen area (MLA) in post-EVT IVUS images according to calcification severity. The secondary outcomes included rates of stent malapposition, restenosis, and clinically-driven target lesion revascularization (TLR). RESULTS: A total of 102 (78.5%) cases had calcification in the lesions over a mean length of 64.3±72.8 mm. Of these, 70 cases were classified as having bilateral calcification according to fluoroscopy and angiography; 50 (49%) lesions had ≥180° calcification according to IVUS. The lumen gain in calcified lesions was significantly smaller than in the 28 noncalcified lesions (14.1±4.4 vs 17.8±5.2 mm2, p<0.001). IVUS-evaluated circumferential distribution of calcium (<180° or ≥180°) was independently associated with lumen gain after EVT (p<0.001). Among the calcification characteristics, a calcification angle ≥180° showed the strongest correlation to postprocedure MLA. Moreover, the restenosis rate was significantly higher in the severe (≥180°) calcification group (p<0.018). The severity of calcification was also associated with the risk of stent malapposition (p=0.022 for trend) but not TLR (p=0.57). CONCLUSION: IVUS evaluation of calcification in SFA lesions predicted lumen gain after EVT. Severe calcification in a ≥180° arc prevented successful dilation of the lesion with either plain balloon angioplasty or a nitinol stent. Accurate assessment of calcification patterns by IVUS is useful in maximizing the efficacy of endovascular therapy.

Clinical Effects of Planned Endovascular Therapy for Critical Limb Ischemia Patients with Tissue Loss.

AIM: The aim of this study was to investigate the clinical effect of planned endovascular therapy (EVT) for critical limb ischemia (CLI) patients with tissue loss. Although several rounds of EVT for CLI patients are required for complete wound healing, time required for complete wound healing depends on the wound severity. We hypothesized that planned EVT might reduce the time to wound healing. METHODS: A total of 89 limbs of 76 CLI patients with tissue loss, who had undergone more than at least two EVTs were included in this study. From January 2013 through December 2015 (Conventional-EVT-group, 52 limbs), indication of target lesion revascularization (TLR) was decided based on decreased skin perfusion pressure (SPP) values or delayed wound healing. From January 2016 through October 2016 (Planned-EVT-group, 37 limbs), TLR were done every two months regardless of the SPP values until complete wound healing was obtained. Time to wound healing and complete wound healing rates were compared between the two groups. RESULTS: No significant differences existed in baseline patients and lesion characteristics between the two groups. There was no significant difference in total EVT numbers between the two groups (2.0; interquartile range, 2.0-3.0 versus 2.0; interquartile range, 2.0-3.0; P=0.9). Although complete wound healing rate was similar in both groups (71.2% versus 73.0%, p=1.0), time to wound healing was significantly shorter (95 days versus 143 days, p=0.025) in the Planned-EVT-group than in the Conventional-EVT-group. CONCLUSIONS: Planned-EVT is a useful strategy to shorten the time to wound healing for CLI patients with tissue loss.

Utility of indigo carmine angiography in patients with critical limb ischemia: Prospective multi-center intervention study (DIESEL-study).

OBJECTIVES: To assess the efficacy of indigo carmine angiography for wound healing after successful below-the-knee intervention in patients with critical limb ischemia (CLI). METHODS: A multi-center prospective intervention study was conducted. Fifty-four limbs of 53 patients in Rutherford categories 5 and 6 underwent endovascular therapy (EVT). After successful EVT, 5 mL of indigo carmine was injected through a catheter at the distal popliteal artery and color changes in the foot were evaluated. The results of indigo carmine angiography were divided into three groups: In type I, the color change of the wound was deeper than the surrounding tissue; in type II, the change in wound color was similar to the surrounding tissue; and in type III, no discoloration of the wound was observed by the indigo carmine. RESULTS: The wound healing rates at 3 months were 78% (25/32) for type I, 70% (7/10) for type II, and 42% (5/12) for type III (P for trend = 0.025). Indigo carmine angiography-related complications were not seen. CONCLUSION: Indigo carmine angiography was found to be a safe and useful procedure to provide visual information on foot perfusion. This dye coloring method demonstrated that after successful angioplasty, the perfused area was made visible at the microcirculation level. Indigo carmine angiography can thus be considered an important predictor for wound healing by EVT in patients with CLI.

Impact of low tissue backscattering by optical coherence tomography on endothelial function after drug-eluting stent implantation.

This study evaluated the impact of optical coherence tomography (OCT)-derived low-backscattered tissue on mid-term coronary endothelial function after drug-eluting stent (DES) implantation. Although OCT enables detailed in vivo evaluation of neointimal tissue characterization after DES implantation, its association with physiological vascular healing response is unclear. Thirty-three stable angina pectoris patients underwent OCT examination and endothelial function testing with intracoronary infusion of incremental doses of acetylcholine 8-month after DES implantation in a single lesion of the left anterior descending artery. Neointimal tissue was classified into two patterns based on the predominant OCT light backscatter: high backscatter and low backscatter. Although the presence of uncovered or malapposed stent strut was not associated with the degree of vasoconstriction, the degree of vasoconstriction was significantly greater in the DES with low-backscattered neointima than in the DES without low-backscattered neointima (- 32.1 ± 25.7 vs. - 4.1 ± 20.1%, p = 0.003). Moreover, there was an inverse linear relationship between low backscatter tissue index and degree of vasoconstriction after acetylcholine infusion (r = 0.50 and p = 0.003). The endothelium-dependent vasomotor response after 8-month of DES was impaired in patients with low neointimal tissue backscatter on OCT imaging. OCT assessment of low-backscattered tissue may be used as surrogate markers for impairment of endothelial function after DES.