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.

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.

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.

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.

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.

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.

Impact of analysis interval size on the quality of optical frequency domain imaging assessments of stent implantation for lesions of the superficial femoral artery.

OBJECTIVES: This study aimed to investigate the influence of analysis interval size on optical frequency domain imaging (OFDI) assessment of stent therapy for lesions of the superficial femoral artery (SFA). BACKGROUND: No consensus or validating data are available with respect to the methodology of intravascular imaging analysis for the peripheral arteries. METHODS: OFDI was performed for 30 SFA lesions, during endovascular therapy and at the 6-month follow-up. Initially, lumen and stent borders were traced at 1-mm axial intervals. Volumes were calculated using a PC-based software, and the volume index (VI) was defined as the volume divided by the stent length. Two additional OFDI analyses were performed using 2-mm and 5-mm intervals, thereby reducing the number of cross-sectional image frames analyzed. RESULTS: The mean stent length was 89.7 ± 35.2 mm. The mean difference in baseline minimum lumen area (MLA) was 0.4 mm2 between MLA values from the 1-mm and 2-mm interval analyses, and 2.2 mm2 between MLA values from the 1-mm and 5-mm interval analyses. In volumetric analysis, there were excellent correlations and good agreements for stent, lumen, and neointimal VI measurements obtained on the basis of different analysis intervals. CONCLUSIONS: Using large intervals in OFDI analyses of SFA lesions resulted in few differences in measurement variability of volumetric parameters. However, planar analysis for MLA assessment can be susceptible to high variability when large intervals are applied. © 2016 Wiley Periodicals, Inc.

The distribution of calcified nodule and plaque rupture in patients with peripheral artery disease: an intravascular ultrasound analysis.

In addition to plaque rupture (PR), calcified nodule (CN) may also have the potential to develop into arterial thrombus in the peripheral arteries. This study evaluated the distribution of plaque ruptures and calcified nodules in the peripheral arteries and their impact on the outcome of endovascular therapy (EVT). Consecutive 159 patients who underwent EVT with intravascular ultrasound guidance were enrolled. The position of CNs and PRs were assigned to any of common iliac artery, external iliac artery, common femoral artery, and superficial femoral artery. Forty-six (29%) patients had calcified nodule and twenty-eight (18%) patients had plaque rupture somewhere in the lower limb arteries. Although calcified nodules were evenly distributed throughout the length of the arteries plaque ruptures were predominantly located in the proximal segment of the iliofemoral arteries. Stent expansion ratio was significantly smaller in the target arteries with calcified nodules than in those with plaque rupture. Multivariate logistic regression analysis identified hemodialysis as an independent clinical predictor of calcified nodule (odds ratio 8.15, 95% confidence interval 1.73-38.3; P = 0.008). CN definitely affects incomplete stent deployment in the peripheral artery contributing to adverse events, on the other hand, PR has more acceptable outcomes after stent implantation. In the clinical setting, it is important that we realize the features of peripheral artery disease and its patient characteristics which having CNs and PRs to make a strategy for revascularization.

Impact of thermodilution-derived coronary blood flow patterns after percutaneous coronary intervention on mid-term left ventricular remodeling in patients with ST elevation myocardial infarction.

We recently reported the coronary thermodilution curve can be evaluated by analyzing the thermodilution curve obtained from a pressure sensor/thermistor-tipped guidewire, and presence of a bimodal-shaped thermodilution curve following primary percutaneous coronary intervention (pPCI) in ST-segment elevation myocardial infarction (STEMI) patients was associated with worse outcomes. This study evaluated whether the bimodal-shaped thermodilution curve predicts left ventricular (LV) remodeling after STEMI. The coronary thermodilution curve patterns were evaluated for 75 patients treated by pPCI for their first STEMI using a pressure sensor/thermistor-tipped guidewire, and classified into the three groups according to the thermodilution curve shape: narrow unimodal (n = 39), wide unimodal (n = 26), and bimodal pattern (n = 10). Echocardiography was performed at baseline and 6 months after STEMI. LV remodeling was defined as a >20 % increase in LV end-diastolic volumes (LVEDV). LVEDV at 6-month follow-up was greater in the bimodal group than in the other groups (p < 0.001). The prevalence of LV remodeling was highest in the bimodal group than in the narrow and wide unimodal groups (60, 12, and 15 %, respectively; p = 0.003). Multivariate analysis revealed a bimodal-shaped thermodilution curve as an independent predictor of the prevalence of LV remodeling. A bimodal-shaped thermodilution curve is associated with LV remodeling after STEMI. This easily assessable coronary thermodilution curve pattern is useful to predict mid-term LV remodeling for STEMI patients at the catheterization laboratory.

Efficacy of CilostAzol for Below-the-Knee Artery Disease after Balloon AnGioplasty in PatiEnts with Severe Limb Ischemia (CABBAGE Trial).

BACKGROUND: Optimal medical therapy after endovascular therapy in patients with critical limb ischemia (CLI) remains unclear. Therefore, we investigated whether cilostazol reduce restenosis after balloon angioplasty for infrapopliteal lesions in CLI patients. METHODS: This study was performed as a multicenter, prospective, randomized, open-label, blinded-end point study with independent angiographic core laboratory adjudication. Sixty patients were eligible and 53 patients were enrolled and allocated. The primary end point was 3-month angiographic restenosis. The main secondary end points included major adverse limb event (MALE defined as requirement of any reintervention or major amputation), perioperative complications, major amputation, all-cause death, and hemorrhagic events. RESULTS: A total of 53 patients were randomized and all received their allocated intervention. Two patients in the cilostazol plus aspirin group and 1 in the aspirin group did not undergo any angioplasty for infrapopliteal stenotic lesions, and therefore were excluded from analysis. Finally, 38 vessels in 25 patients in the cilostazol plus aspirin group and as many cases in the aspirin group were included in the analysis. There were no significant differences in baseline characteristics between the 2 groups. The 3-month restenosis rate was 82% in the cilostazol + aspirin group and 81% in the aspirin group, with no significant difference (P = 0.91). The MALE rate was 11% in the cilostazol plus aspirin group and 8% in the aspirin group (P = 0.73). In addition, no significant difference was observed in any secondary points. CONCLUSIONS: Cilostazol did not reduce 3-month angiographic restenosis after balloon angioplasty for below-the-knee lesion in CLI patients.

Morphological, Functional, and Biological Vascular Healing Response 6 Months After Drug-Eluting Stent Implantation: A Randomized Comparison of Three Drug-Eluting Stents.

OBJECTIVES: This study evaluated coronary endothelial function after the implantation of sirolimus-eluting stents (SESs), everolimus-eluting stents (EESs), and zotarolimus-eluting stents (ZES) by a different methodology, and also analyzed whether optical coherence tomography (OCT) findings represent endothelial healing after stenting. BACKGROUND: It is unclear whether OCT assessment of stent strut coverage represents endothelial healing after drug-eluting stent implantation. METHODS: Thirty patients with a left anterior descending artery lesion were randomized 1:1:1 to receive an SES, EES, or ZES. The vascular response was evaluated 6 months after stenting by three methods: the functional response by acetylcholine infusion, the morphological response by OCT, and the biological response by measuring vascular endothelial growth factor (VEGF) levels. RESULTS: The proportion of uncovered struts by OCT at 6 months was significantly higher in both SES and EES than in ZES. However, the vasomotor response was impaired and the VEGF level of the coronary sinus was significantly lower in SES than in EES and ZES. There were no relationships between the OCT findings and vasomotor response to acetylcholine and VEGF levels in all cohorts. CONCLUSIONS: The vascular response at 6 months was more preserved in ZES and EES than in SES. Our results suggest that the morphological assessment with OCT may not always be used as a surrogate for functional and biological healing response after stenting. © 2015 Wiley Periodicals, Inc.

Intravascular Ultrasound-Derived Stent Dimensions as Predictors of Angiographic Restenosis Following Nitinol Stent Implantation in the Superficial Femoral Artery.

PURPOSE: To identify intravascular ultrasound (IVUS) measurements that can predict angiographic in-stent restenosis (ISR) following nitinol stent implantation in superficial femoral artery (SFA) lesions. METHODS: A retrospective review was conducted of 97 patients (mean age 72.9±8.9 years; 63 men) who underwent IVUS examination during endovascular treatment of 112 de novo SFA lesions between July 2012 and December 2014. Self-expanding bare stents were implanted in 46 lesions and paclitaxel-eluting stents in 39 lesions. Six months after stenting, follow-up angiography was conducted to assess stent patency. The primary endpoint was angiographic ISR determined by quantitative vascular angiography analysis at the 6-month follow-up. Variables associated with restenosis were sought in multivariate analysis; the results are presented as the odds ratio (OR) and 95% confidence interval (CI). RESULTS: At follow-up, 27 (31.8%) angiographic ISR lesions were recorded. The lesions treated with uncoated stents were more prevalent in the ISR group compared with the no restenosis group (74.1% vs 44.8%, p=0.02). Lesion length was longer (154.4±79.5 vs 109.0±89.3 mm, p=0.03) and postprocedure minimum stent area (MSA) measured by IVUS was smaller (13.9±2.8 vs 16.3±1.6 mm(2), p<0.001) in the ISR group. Multivariate analysis revealed that bare stent use (OR 7.11, 95% CI 1.70 to 29.80, p<0.01) and longer lesion length (OR 1.08, 95% CI 1.01 to 1.16, p=0.04) were predictors of ISR, while increasing postprocedure MSA (OR 0.58, 95% CI 0.41 to 0.82, p<0.01) was associated with lower risk of ISR. Receiver operating characteristic analysis identified a MSA of 15.5 mm(2) as the optimal cutpoint below which the incidence of restenosis increased (area under the curve 0.769). CONCLUSION: Postprocedure MSA can predict ISR in SFA lesions, which suggests that adequate stent enlargement during angioplasty might be required for superior patency.

Impact of intravascular ultrasound findings on long-term patency after self-expanding nitinol stent implantation in the iliac artery lesion.

Although intravascular ultrasound (IVUS) predictors of stent patency for the coronary artery lesion have been established, little is known about IVUS predictors of stent patency for the aorto-iliac artery lesion. We analyzed 154 lesions of 122 patients who underwent stent implantation for iliac artery lesions. Quantitative and qualitative IVUS analyses were performed for pre- and post-procedural IVUS imaging in all lesions. Target lesion revascularization (TLR) was defined as clinically driven revascularization with >50 % angiographic stenosis of the target lesion. The mean follow-up period was 39 ± 16 months. TLRs were performed in 13 lesions (8.4 %). Post-procedural minimum stent area (MSA) was significantly smaller in the TLR group compared to the no-TLR group (16.0 ± 5.8 vs. 25.6 ± 8.5 mm(2), p < 0.001). Stent edge dissection was frequently observed in the TLR group compared to the no-TLR group (53.8 vs. 24.1 %, p = 0.04). Multivariate analysis revealed that post-procedural MSA (OR = 0.76, p < 0.01) and stent edge dissection (OR = 10.4, p < 0.01) were independent IVUS predictors of TLR. Receiver-operating characteristic analysis identified post-procedural MSA <17.8 mm(2) as the optimal cut-point for the prediction of TLR (AUC = 0.846). Post-procedural MSA and stent edge dissection could predict long-term stent patency in the iliac artery lesion. Our results propose that adequate stent enlargement without edge dissection might be important to reduce TLR in the iliac artery lesion.

Impact of spotty calcification on long-term prediction of future revascularization: a prospective three-vessel intravascular ultrasound study.

To date, there are no prospective studies on the relationship between plaque characteristics identified by 40 MHz IVUS and future adverse events. This prospective study evaluated the relationship between plaque morphology in nonculprit nonsignificant lesions, determined by 40 MHz IVUS, and long-term clinical outcomes. Consecutively, 45 patients who underwent 3-vessel intravascular ultrasound (IVUS) examinations were prospectively enrolled. Qualitative and quantitative IVUS analyses including scoring of echogenicity for assessment of plaque characterization were performed for each nonsignificant nonculprit lesion. The number, the length, the location (superficial or deep), and maximum arc were measured for each calcium deposit within plaques. Spotty calcification was defined as calcium deposits <90° and <6 mm in length. Primary end point was defined as nonsignificant nonculprit lesion-related revascularization (NNLR) during 6 years of follow-up. A total of 163 nonsignificant nonculprit lesions with mild to moderate stenosis were identified on baseline 3-vessel IVUS. Of those 163 lesions, six lesions required NNLR during the follow-up period. There were no differences in quantitative IVUS parameters including remodeling index, plaque burden, and echogenicity between lesions requiring and not requiring NNLR. However, deep spotty calcification was more frequently identified in lesions requiring NNLR than in those not requiring NNLR (33 vs. 8 %, P = 0.02). Spotty calcium deposits identified by 40 MHz IVUS predicted the need for NNLR during a 6-year follow-up period. This finding suggests that deep spotty calcium may be a surrogate marker for plaque progression and the subsequent need for revascularization in the future.

Endovascular therapy by CO2 angiography to prevent contrast-induced nephropathy in patients with chronic kidney disease: a prospective multicenter trial of CO2 angiography registry.

OBJECTIVES: To assess the safety and efficacy of carbon dioxide (CO2) angiography-guided endovascular therapy (EVT) for renal, iliofemoral artery disease. BACKGROUND: Patients with peripheral vascular disease (PVD) often have chronic kidney disease (CKD) and the use of iodinated contrast media may enhance the risk of contrast-induced nephropathy (CIN). Contrast volume reduction is an effective CIN preventive strategy. METHODS: A prospective multicenter registry was developed and six clinical centers participated in the study. Patients with an estimated glomerular filtration rate (eGFR) of <60 ml/min/1.73 m2 and stage-3 CKD were recruited between February 2012 and March 2013. CO2 angiography-guided EVT was performed; incomplete CO2 angiograms were supplemented by intravascular ultrasound, pressure wire, and/or minimal iodinated contrast media. The primary endpoint was a composite of freedom from renal events and freedom from major CO2 angiography related complications. RESULTS: This study included 98 patients with 109 lesions. The mean eGFR baseline was 35.2±12.7 ml min(-1). CO2 angiography-guided angioplasty were performed in 16 renal arteries, 31 aortoiliac arteries, and 62 superficial femoral arteries. The technical success rate was 97.9%. Average CO2 consumption was 281.4±155.8 ml, average dose of iodinated contrast media was 15.0±18.1 ml. Primary endpoint was 92.8% (91/98). Incidence of CIN was 5.1% (5/98) and CO2 angiography-related complications occurred in 17.3% (17/98). Two cases (2%) developed severe, fatal, nonocclusive mesenteric ischemia (NOMI). CONCLUSIONS: This trial showed that CO2 angiography-guided angioplasty was effective for preventing CIN, however, CO2 angiography related complication was somewhat high.

Tissue Characterization of In-Stent Neointima Using Optical Coherence Tomography in the Late Phase After Bare-Metal Stent Implantation--An Ex Vivo Validation Study.

BACKGROUND: We performed an ex vivo study to investigate optical coherence tomography (OCT) imaging for differentiating several types of neointimal tissue during the later phases after bare-metal stent (BMS) implantation as compared with histologic results. METHODS AND RESULTS: OCT imaging was performed in 6 autopsy hearts for 10 BMS with implant duration >4 years. OCT qualitative neointimal tissue characterization was based on tissue structure and classified as homogeneous pattern, heterogeneous pattern with visible struts, or heterogeneous pattern with invisible struts. Corresponding histological analyses of each 2-mm cross-section of the entire BMS were performed. Of 81 cross-sections, histological analysis revealed that the homogeneous pattern of neointima on OCT (n=39) contained smooth muscle cells with collagen, indicating high neointimal maturity. The heterogeneous patterns with visible struts (n=35) contained different tissues, including a proteoglycan-rich myxomatous matrix or dense calcified plate deposition. The heterogeneous patterns with invisible struts (n=7) included neointimal lipid/necrotic core formation, accumulation of foam cells, or microcalcification scattering. Of the 66 cross-sections containing large microvessels within the neointima on histology, only 6 (9%) were visualized by OCT. CONCLUSIONS: The present study confirmed the potential use of OCT in differentiating several types of neointima after BMS implantation. The image interpretation of OCT, based on visualization of stent struts, enables identification of several types of neointimal tissues, including in-stent fibroatheroma formation, more accurately.

Natural history of low-intensity neointimal tissue after an everolimus-eluting stent implantation: a serial observation with optical coherence tomography.

Although previous optical coherence tomography (OCT) studies reported that restenosis tissue after implantation of a drug-eluting stent (DES) was composed of a variety of cells, the clinical significance of morphologic characteristics for in-stent neointimal tissue as assessed by OCT has not been clarified. We experienced a patient with stable angina who underwent percutaneous coronary intervention with a 2.5 × 18-mm DES implantation 6 months before the OCT examination. OCT imaging showed a mild intimal hyperplasia (39 % neointimal hyperplasia) with eccentric, heterogeneous tissue, predominantly of low signal intensity. Seventeen months after the initial procedure, OCT revealed a significant increase in percent neointimal hyperplasia of 58 %, with morphologically different intimal tissue of concentric homogeneous high intensity in the stented segments. This finding suggests that low-intensity intimal tissue morphology detected by OCT could be a morphometric predictor of late neointimal tissue growth after DES implantation.