Impact of lipoprotein(a) levels on primary patency after endovascular therapy for femoropopliteal lesions.

Lipoprotein(a) [Lp(a)] is a risk factor for peripheral artery disease (PAD). However, the relationship between Lp(a) levels and clinical events after endovascular therapy (EVT) for the femoropopliteal artery in PAD patients remains unclear. Thus, this study aimed to assess the impact of Lp(a) levels on primary patency after EVT for de novo femoropopliteal lesions in PAD patients. A retrospective analysis was conducted on 109 patients who underwent EVT for de novo femoropopliteal lesions, and Lp(a) levels were measured before EVT between June 2016 and December 2019. Patients were divided into low Lp(a) [Lp(a) < 30 mg/dL; 78 patients] and high Lp(a) [Lp(a) ≥ 30 mg/dL; 31 patients] groups. The main outcome was primary patency following EVT. Loss of primary patency was defined as a peak systolic velocity ratio > 2.4 on a duplex scan or > 50% stenosis on angiography. Cox proportional hazards analysis was performed to determine whether high Lp(a) levels were independently associated with loss of primary patency. The mean follow-up duration was 28 months. The rates of primary patency were 83 and 76% at 1 year and 75 and 58% at 2 years in the low and high Lp(a) groups, respectively (P = 0.02). After multivariate analysis, High Lp(a)[Lp(a) ≥ 30 mg/dL] (hazard ratio 2.44; 95% CI 1.10-5.44; P = 0.03) and female sex (hazard ratio 2.65; 95% CI 1.27-5.51; P < 0.01) were independent predictors of loss of primary patency. Lp(a) levels might be associated with primary patency after EVT for de novo femoropopliteal lesions.

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.

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.

Influence of Self-Expanding Paclitaxel-Eluting Stent Sizing on Neointimal Hyperplasia in Superficial Femoral Artery Lesions.

BACKGROUND: Although self-expanding drug-eluting stents (DES) have recently shown superior outcomes for superficial femoral artery (SFA) lesions, optimal sizing of DES diameter in SFA intervention is unclear.Methods and Results:A total of 40 de novo SFA lesions were randomized 1:1 to receive self-expanding DES with either a 1-mm or 2-mm larger diameter than the reference vessel diameter. Follow-up optical coherence tomography (OCT) was scheduled 6 months after DES implantation to evaluate the vascular response to the stents. Volume index (VI) was defined as volume divided by stent length. The primary endpoint was neointimal VI at 6 months. Baseline reference vessel diameter was similar between the 1-mm larger diameter group and the 2-mm larger diameter group (5.0±0.8 mm vs. 4.7±0.9 mm, P=0.35). Stent diameter was 6.3±0.6 mm in the 1-mm larger group and 7.1±0.6 mm in the 2-mm larger group (P<0.0001), and stent to reference vessel diameter ratio (SV ratio) was 1.3±0.2 and 1.5±0.2 (P<0.0001), respectively. At 6-month, neointimal VI was greater in the 2-mm larger diameter group (5.5±1.5 mm2vs. 9.6±3.4 mm2, P<0.001). The correlation analysis revealed that degree of neointimal VI was positively correlated with SV ratio (r=0.43, P<0.01). CONCLUSIONS: Implantation of self-expanding DES with a considerably high SV ratio resulted in neointimal hyperplasia in SFA lesions.

Endovascular Therapy with a Covered Stent Graft for Pseudoaneurysm of the Peroneal Artery Complicating High Tibial Osteotomy-A Case Report.

Pseudoaneurysm of below-the-knee arteries after a high tibial osteotomy (HTO) is rare. A 69-year-old woman with history of right HTO a half year ago had performed a left HTO for osteoarthritis. Postoperatively, she had swelling and pain of the left lower leg. Computed tomography and echocardiography revealed the pseudoaneurysm of peroneal artery (PA). After the release of the covered stent graft, the pseudoaneurysm of the PA did not disappear, it was completely excluded in the completion angiogram.

Open sesame technique in percutaneous coronary intervention for ST-elevation myocardial infarction.

In patients with ST-elevation myocardial infarction (STEMI), delays in reperfusion attenuate the benefit of primary percutaneous coronary intervention (PCI) and associate with higher mortality rates. Although PCI operators are making their best effort in time saving for reperfusion, it is sometimes challenging and takes time to pass the guide wire across the target lesions. A totally occluded lesion in which a side branch was bifurcating at the proximal end of the occluded segment is one of the most technically challenging anatomies of the target lesion because it is difficult to identify the entry point of the occluded segment. A side branch technique, termed "Open Sesame Technique" (OST), has been previously introduced for chronic total occlusion (CTO) lesion in which a side branch was bifurcating at the proximal end of the occluded segment. We herein present two cases applying this technique in STEMI with totally occluded lesions at bifurcation as a culprit lesion, in which the entry point was not identified on the initial angiography. PCI were performed successfully using the OST in both cases, which resulted in saving procedural time and contrast volume without any complications. This technique can be effective not only in PCI for CTO lesions but also in primary PCI for STEMI cases with occluded bifurcation lesions.

Atherosclerotic Component of the Yellow Segment After Drug-Eluting Stent Implantation on Coronary Angioscopy　- An Ex-Vivo Validation Study.

BACKGROUND: Coronary angioscopy (CAS) is used to comprehensively evaluate vascular responses after drug-eluting stent (DES) implantation. This study sought to evaluate the capability of CAS for evaluating DES strut coverage grade and color grade of the intima compared with histological images in coronary autopsy specimens. Methods and Results: A total of 23 DES extracted from 11 autopsy hearts were imaged by CAS. All stent segments were graded as white or yellow according to the luminal surface color, and thrombus was evaluated according to a previous report. Neointimal coverage over the DES was graded as 0 (stent struts fully visible) to grade 3 (stent struts fully embedded and invisible). Of 76 segments, neointimal coverage was graded as 0 in 35 (46%), 1 in 22 (29%), 2 in 8 (11%), and 3 in 11 (14%). The neointimal thickness increased significantly with increasing neointimal coverage grade on angioscopy. Neointimal color was graded as white in 40 (53%) and yellow in 36 segments (47%). Histological analysis revealed that yellow neointima contained fibroatheroma, foam cells accumulation or superficial calcium deposition. A thrombus was identified in 13 segments. Thrombi adherent around the stent strut were partly intimal erythrocyte accumulation around the strut. CONCLUSIONS: In-stent yellow segment had atherosclerotic components. CAS could evaluate vascular status comprehensively after DES implantation.

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.

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.

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.

Effect of bare-metal nitinol stent implantation and paclitaxel-eluting nitinol stent implantation on vascular response in the superficial femoral artery lesion assessed on intravascular ultrasound.

BACKGROUND: Although previous intravascular ultrasound (IVUS) studies reported that the drug-eluting stent (DES) has successfully decreased in-stent restenosis (ISR) by inhibiting neointimal hyperplasia (NIH) in the coronary artery lesion, no IVUS data for vascular response after DES implantation in the superficial femoral artery (SFA) have been published. METHODS AND RESULTS: We retrospectively analyzed 38 de novo SFA lesions from 32 patients who underwent endovascular therapy (EVT) with self-expanding bare-metal nitinol stent (25 lesions; BMS group) or self-expanding paclitaxel-eluting nitinol stents (13 lesions; PES group). At 6 months after EVT, follow-up IVUS was done to evaluate NIH. Serial IVUS volumetric analysis was done after stent deployment and at follow-up. Mean stent, lumen and neointimal areas were calculated as the volume divided by the stent length. The primary endpoint of this study was mean late lumen loss at 6-month follow-up. The mean follow-up period was 189±39 days. Mean neointimal area was smaller in the PES group compared to the BMS group (3.3±1.0mm(2) vs. 10.2±4.1mm(2), P<0.001). Mean late lumen loss was significantly lower in the PES group compared to the BMS group (-2.3±3.7mm(2) vs. 2.1±4.7mm(2), P<0.05). CONCLUSIONS: EVT with DES in SFA lesions might decrease NIH associated with ISR in short-term follow-up.

Impact of post-procedural intravascular ultrasound findings on long-term results following self-expanding nitinol stenting in superficial femoral artery lesions.

BACKGROUND: Previous intravascular ultrasound (IVUS) studies have reported that a tiny reference cross-sectional area (CSA), stent under-expansion, stent asymmetry, stent edge dissection, and tissue protrusion are associated with target lesion revascularization (TLR) after coronary intervention. In the lower limb, however, it has not been reported that these findings correlate with TLR after endovascular therapy (EVT). METHODS AND RESULTS: A total of 236 consecutive superficial femoral artery (SFA) lesions in patients who underwent IVUS after self-expanding nitinol stent implantation, were analyzed. Stent expansion ratio was calculated as minimum stent CSA/reference lumen CSA, radial stent symmetry index as minimum/maximum stent diameter, and axial stent symmetry index as minimum/maximum stent CSA. TLR was defined as clinically driven revascularization with ≥75% restenosis of the target lesion. The mean follow-up period was 34±15 months. TLR were performed in 42 lesions (17.8%). There were no significant differences in stent expansion ratio, stent symmetry indices, and tissue protrusion between the TLR and no-TLR groups. Multivariate analysis indicated that total stent length (odds ratio [OR], 1.004; P<0.05), distal reference CSA (OR, 0.91; P<0.01), and stent edge dissection (OR, 3.51; P<0.01) were independent predictors of TLR. CONCLUSIONS: Stent implantation in tiny vessels and stent edge dissection in SFA lesions are indicators of high risk of TLR. Post-procedural stent under-expansion and stent asymmetry, however, were not associated with TLR.

Heterogeneous vascular response after implantation of bare nitinol self-expanding stents in the swine femoropopliteal artery.

BACKGROUND: Mechanism of femoropopliteal in-stent restenosis has been underappreciated. AIM: The aim of this animal study was to elucidate vascular response after femoropopliteal bare nitinol self-expanding stents (SESs) implantation. METHODS: Misago, Smart Flex, or Innova stent was randomly implanted in 36 swine femoropopliteal arteries. At week 4, quantitative vessel analysis (QVA) was performed on 36 legs, of which 18 underwent histological evaluation after angiography. The remaining 18 legs underwent QVA and histological evaluation at week 13. RESULTS: Fibrin deposition was excessive at week 4. Internal elastic lamina (IEL) progressively enlarged over time, and vessel injury developed from mild level at week 4 to moderate level at week 13. Vessel inflammatory reaction was mild to moderate at week 4, and was moderate to severe at week 13. Increased fibrin deposition was an early-acting, IEL enlargement and increased vessel inflammation were long-acting, and increased vessel injury and giant cells infiltration were late-acting contributors to neointimal hyperplasia (NIH). Stent type altered time-dependent process of vessel injury, vessel inflammation, eosinophils and giant cells infiltration. Misago had less fibrin deposition and vessel enlargement, and less progressive vessel injury, vessel inflammation, and eosinophils and giant cells infiltration. Net lumen as assessed by percent diameter stenosis or minimum lumen diameter was preserved with Misago, but was not preserved with the other stents. CONCLUSIONS: In the context of bare nitinol SES platform with less progressive mechanical stress and inflammatory reaction, the advantage of less NIH outweighed the disadvantage of less vessel enlargement, leading to net lumen preservation.

Impact of lipoprotein (a) on long-term outcome after percutaneous coronary intervention in the era of new generation drug-eluting stents.

BACKGROUND: High lipoprotein (a) [Lp (a)] levels are associated with worse long-term outcomes in patients undergoing percutaneous coronary intervention (PCI). However, there are limited studies investigating association between Lp (a) levels and long-term outcomes in the era of new generation drug-eluting stents (DES). METHODS: A total of 495 patients with available data on Lp (a) who underwent PCI for de novo lesions with new generation DES were enrolled between 2013 and 2017. The primary endpoint was the major adverse cardiovascular event (MACE), which was defined as a composite of cardiac death, myocardial infarction, stent thrombosis, clinically driven target lesion revascularization, and revascularization for new lesions during 3 years. Patients were divided into 2 groups according to the Lp (a) level: high Lp (a) group (≥30 mg/dL: n = 109) and low Lp (a) group (30 mg/dL>: n = 386). Multivariate Cox regression analysis was performed to identify the predictors for 3-year MACE. RESULTS: The incidence of 3-year MACE was significantly higher in high Lp (a) group than low Lp (a) group (33.0% vs. 15.9%, p < 0.001). Multivariable analysis showed that Lp (a) level of ≥30 mg/dL was an independent predictor for 3-year MACE (HR 2.01, 95%CI 1.30-3.11, p = 0.002). CONCLUSION: High Lp (a) level was associated with worse long-term outcome even in the era of new generation DES.