Intravascular Ultrasound Guidance Research Articles

Outcomes of optical coherence tomography compared with intravascular ultrasound and with angiography to guide coronary stent implantation: one-year results from the ILUMIEN III: OPTIMIZE PCI trial.

In the ILUMIEN III trial, among 450 randomised patients with non-complex lesions undergoing percutaneous coronary intervention (PCI), optical coherence tomography (OCT) guidance led to greater stent expansion than angiography guidance, similar minimal stent area compared to both intravascular ultrasound (IVUS) guidance and angiography guidance, and lower rates of uncorrected dissection and malapposition than both IVUS guidance and angiography guidance. Whether these differences impact on clinical outcomes is unknown. The aim of the present study was to report the 12-month clinical follow-up data from the ILUMIEN III study. OCT-guided PCI, using an external elastic lamina-based protocol, was compared to operator-directed IVUS-guided or angiography-guided PCI. Target lesion failure (TLF) and major adverse cardiovascular events (MACE) at 12 months were adjudicated by a blinded clinical events committee. There were no significant differences in the rates of TLF (2.0% OCT, 3.7% IVUS, 1.4% angiography), MACE (9.8% OCT, 9.1% IVUS, 7.9% angiography), or any of the individual components of these outcomes among the groups. No independent predictors of 12-month stent-related clinical events were identified from final OCT. In this underpowered study, OCT-guided PCI of non-complex lesions did not show a statistical difference in clinical outcomes at 12 months compared with IVUS or angiography guidance. An appropriately powered trial, including only complex patients and lesions, is underway to substantiate the potential clinical benefit of OCT-guided PCI. NCT02471586.

Intravascular ultrasound guidance for valve-in-valve transcatheter pulmonary valve replacement.

Intravascular ultrasound guidance for valve-in-valve transcatheter pulmonary valve replacement.

Multicenter experience with percutaneous coronary intervention for chronic total occlusion in Korean population: analysis of the Korean nationwide multicenter chronic total occlusion registry.

Percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) remains challenging because of limited success and higher target vessel failure rates. Detailed safety and efficacy data for CTO-PCI from a multicenter real-world Korean registry are limited. Since May 2007, the Korean multicenter retrospective CTO registry has enrolled 3271 patients who underwent CTO-PCI at 26 major medical centers. Baseline clinical, angiographic, and procedural characteristics and 12-month major adverse cardiac event (MACE) rates after PCI were retrospectively collected. Baseline cardiovascular risk factors included: male sex, 73.8%; prior myocardial infarction (MI), 14.8%; prior PCI, 26.6%; hypertension, 62.3%; diabetes mellitus, 34.8%; dyslipidemia, 33.3%; and current smoker, 30.9%. Pre-PCI myocardial viability testing was performed in 23.6% of patients and pre-PCI cardiac computed tomography (CT) in 17.6%. CTO arterial lesions were distributed as follows: right coronary, 41.0%; left anterior descending, 40.0%; left circumflex, 22.5%; and left main, 0.4%. Unfavorable lesion morphology was detected by angiography in 38.1%. Intravascular ultrasound guidance and the retrograde approach were utilized in 23.6 and 3.1% of CTO-PCI procedures, respectively. More than 75% of patients received drug-eluting stents (sirolimus-eluting, 26.5%; paclitaxel-eluting, 23.8%; zotarolimus-eluting, 23.4%; everolimus-eluting, 11.0%; and others, 4.0%). The overall success rate was 81.6% (2672/3271 patients). Twelve-month event rates were: total mortality, 2.4%; any MI, 0.7%; target lesion revascularization, 4.4%; target vessel revascularization, 6.7%; and total MACE, 9.4%. Twelve-month success rates, safety profiles, and cumulative clinical outcomes of Korean CTO patients were favorable post-PCI. Long-term follow-up of larger study populations is necessary to validate our findings.

Outcomes of predefined optimisation criteria for intravascular ultrasound guidance of left main stenting.

This study sought to investigate the prognostic effect of a protocol with optimisation targets for intravascular ultrasound (IVUS)-guided left main (LM) revascularisation. A protocol was prospectively applied for IVUS-guided LM revascularisation (IVUS-PRO group) including predefined optimisation targets. Using propensity score matching, we selected as control groups patients with angiography-guided PCI (ANGIO group) and IVUS-guided PCI (IVUS group) from a large multicentre registry. The primary endpoint was a composite of cardiac death, LM-related infarction and LM revascularisation at 12 months. In each group, 124 patients with comparable characteristics were included. The incidence of the primary outcome was significantly higher in the ANGIO group compared to the IVUS-PRO group (12.9% vs 4.8%, HR 0.35, 95% CI: 0.15 to 0.82, p=0.02), but not with respect to the IVUS group (12.9% vs 8%, HR 0.51, 95% CI: 0.20 to 1.22, p=0.1), driven by a lower rate of LM revascularisation (8% in the ANGIO group, 6.4% in the IVUS group and 3.2% in the IVUS-PRO group). IVUS-PRO resulted in being an independent risk predictor (HR 0.45, 95% CI: 0.15 to 0.98; p=0.041). IVUS guidance of LM stenting provides prognostic benefit with respect to the use of angiography alone, particularly when following a protocol with these predefined optimisation criteria.

Acute and one-year clinical outcomes of pre-stenting intravascular ultrasound: a patient-level meta-analysis of randomised clinical trials.

Pre-stenting intravascular ultrasound (IVUS) assessment is helpful for appropriate stent sizing and determination of the stent landing zone during percutaneous coronary intervention. The aim of this meta-analysis was to investigate the effect of pre-stenting IVUS evaluation on procedural and clinical outcomes for diffuse lesions treated with drug-eluting stents (DES). In four randomised trials comparing IVUS- and angiography-guided DES placement, a total of 1,396 patients who underwent DES implantation with IVUS guidance were identified. Pre-stenting IVUS assessment was performed in 905 patients along with post-stenting IVUS (65%; pre-stenting IVUS(+) group). Post-stenting IVUS evaluation alone was conducted on 491 patients (35%; pre-stenting IVUS(-) group). The pre-stenting IVUS(+) group had a larger angiographic minimal lumen diameter and IVUS-derived minimal stent area (MSA) than did the pre-stenting IVUS(-) group. After adjusting, these findings were consistent. The one-year composite of cardiac death, myocardial infarction, and target vessel revascularisation did not differ between the groups. In subgroup analysis, the pre-IVUS(+) group was significantly favoured over the pre-IVUS(-) group in the subset of patients with acute myocardial infarction and lesions with small vessels in terms of larger MSA, and in the subset of patients with chronic total occlusions in terms of better clinical outcomes. Pre-stenting IVUS assessment prior to DES placement was associated with better acute procedural outcomes, though this did not translate into one-year clinical outcomes in the context of post-stenting IVUS assessment. Visual summary. Acute and one-year outcomes of pre-stenting intravascular ultrasound: a meta-analysis of randomised clinical trials.

Intravascular Ultrasound-guided Versus Angiography-guided Percutaneous Coronary Intervention: Evidence from Observational Studies and Randomized Controlled Trials

Coronary angiography has been considered the gold standard for the diagnosis of coronary artery disease and guidance of percutaneous coronary intervention (PCI). However, 2D-projection angiography cannot completely reflect the 3D coronary lumen. Intravascular ultrasound (IVUS) can overcome a number of limitations of coronary angiography by providing more information about the dimensions of the vessel lumen, plaque characteristics, stent deployment, and the mechanisms of device failure. Growing data from observational studies and randomized controlled trials have confirmed the clinical benefit of IVUS guidance during PCI. This article summarizes the evidence regarding IVUS guidance to highlight its advantages and to support the use of IVUS during PCI.

OPtical frequency domain imaging vs. INtravascular ultrasound in percutaneous coronary InterventiON in patients with Acute Coronary Syndrome: Study protocol for a randomized controlled trial

BackgroundA recent clinical trial demonstrated that optical frequency domain imaging (OFDI) guidance in percutaneous coronary intervention (PCI) is noninferior to intravascular ultrasound (IVUS) guidance in patients with coronary artery disease with regard to target vessel failure (composed of cardiac death, myocardial infarction attributed to the target vessel, and clinically-driven target vessel revascularization) at 12 months. The impact of OFDI guidance in PCI for patients with acute coronary syndrome (ACS) remains uncertain. MethodsOPINION ACS is a multicenter, prospective, randomized, controlled, open-label, parallel group, non-inferiority trial in Japan. Eligible patients will be randomly assigned to receive either OFDI- or IVUS-guided PCI. PCI is performed using the sirolimus-eluting stent in accordance with certain OFDI and IVUS criteria for optimal stent deployment. All patients will undergo follow-up angiography and OFDI imaging at 8 months. The primary endpoint is the minimum lumen area, as measured by OFDI at 8 months. ConclusionThe OPINION ACS trial outcomes will provide insights regarding the impact of OFDI-guided PCI on in-stent restenosis at 8 months in patients with ACS.

Intravascular ultrasound online guidance during transcatheter valve replacement for native aortic stenosis or failed bioprosthesis.

Intravascular ultrasound online guidance during transcatheter valve replacement for native aortic stenosis or failed bioprosthesis.

Improving Outcomes With IVUS Guidance During Percutaneous Coronary Interventions

This review highlights the evidence surrounding the adjunctive diagnostic and therapeutic benefits of intravascular ultrasound (IVUS) during percutaneous coronary intervention (PCI). Meta-analyses of randomized trials demonstrate that IVUS has a major impact on PCI-related outcomes with drug-eluting stents by reducing cardiovascular mortality and repeat revascularization. Its application in calcific coronary artery disease has helped identify the benefits and safety of coronary atherectomy, along with playing an important role for primarily guiding PCI while significantly reducing contrast volume in individuals with renal dysfunction. IVUS applications have been extended to the realms of CTO intervention, aneurysmal coronary disease, and iatrogenic/spontaneous coronary artery dissection. IVUS is also a proven cost-effective strategy. Nevertheless, despite these benefits, the global uptake of IVUS-guided PCI remains low. IVUS plays a pivotal role during PCI, particularly complex calcific and long lesions. IVUS-guided PCI is safe, cost-effective, and associates with substantial reductions in MACE. However, the worldwide uptake of IVUS-guided PCI remains considerably low. Further efforts are required to promote this evidence-based PCI strategy among the global interventional cardiology community to further improve the outcomes of our PCI candidates.

Editorial: Rotational Atherectomy Followed by Drug-Coated Balloons in Calcified Coronary De Novo Lesions – An Alternative to Stent Implantation?

Intravascular ultrasound (IVUS)–guided percutaneous coronary intervention (PCI) has been shown in clinical trials, registries, and meta-analyses to reduce recurrent major adverse cardiovascular events after PCI. However, IVUS utilization remains low. An increasing number of high-risk or complex coronary artery lesions are treated with PCI, and we hypothesize that the impact of IVUS in guiding treatment of these complex lesions will be of increased importance in reducing major adverse cardiovascular events while remaining cost-effective. The “IMPact on Revascularization Outcomes of intraVascular ultrasound-guided treatment of complex lesions and Economic impact” trial (registered on clinicaltrials.gov: NCT04221815) is a multicenter, international, clinical trial randomizing subjects to IVUS-guided versus angiography-guided PCI in a 1:1 ratio. Patients undergoing PCI involving a complex lesion are eligible for enrollment. Complex lesion is defined as involving at least 1 of the following characteristics: chronic total occlusion, in-stent restenosis, severe coronary artery calcification, long lesion (≥28 mm), or bifurcation lesion. The clinical investigation will be conducted at approximately 120 centers in North America and Europe, enrolling approximately 2,500 to 3,100 randomized subjects with an adaptive design. The primary clinical end point is the rate of target vessel failure at 12 months, defined as the composite of cardiac death, target vessel–related myocardial infarction, and ischemia-driven target vessel revascularization. The co-primary imaging end point is the final post-PCI minimum stent area assessed by IVUS. The primary objective of this study is to assess the impact of IVUS guidance on the PCI treatment of complex lesions.

Intravascular Imaging for Peripheral Vascular Disease and Endovascular Intervention

Intravascular imaging has been increasingly incorporated into endovascular practice. The goal of this review is to explore the contemporary technologies used to perform intravascular imaging as well as the evidence supporting their use in the diagnostic assessment and treatment of peripheral vascular disease. Although intravascular imaging has been more extensively studied in the coronary vasculature, there is a growing body of literature studying its use in other vascular territories. There are unique advantages and disadvantages for the two most commonly employed imaging modalities—intravascular ultrasound (IVUS) and optical coherence tomography (OCT). Either may enhance the diagnostic capabilities of conventional angiography depending upon the clinical situation. IVUS and OCT guidance for angioplasty and stent sizing in peripheral interventions has been shown to be safe, feasible and in many instances, effective. Studies suggest that clinically relevant outcomes such as vessel primary patency and long-term patency may be improved by utilizing these imaging technologies. While still employed as adjunctive modalities to angiography and peripheral intervention, IVUS or OCT may provide a potential pathway towards improving short- and long-term outcomes for a variety of vascular disease entities. At this time, further research is still warranted to better define the optimal role for these devices in non-coronary vascular beds.

Case Report: The Role of Intravascular Ultrasonography in Patients Underwent Percutaneous Coronary Intervention

Intravascular ultrasonography (IVUS) has an important role as a complimentary diagnostic tool in percutaneous coronary intervention procedure. IVUS provides valuable information regarding coronary vessel lumen and dimension and also plaque burden and its characteristic. The main use of IVUS in PCI is to guide the choose of interventional strategies to optimize stent deployment. Since drug eluting stent (DES) has promised to decrease the incidence in stent restenosis and stent thrombosis than bare metal stent, but neither the suboptimal results nor the complication after stenting with DES is still high. Thus, optimization of stent deployment under IVUS guidance is important in cases to decrease stent failure after PCI procedure, as well as to decrease complication rate after stenting in order to decrease mortality rate caused by coronary artery disease. We present here the use of IVUS guidance in a 43 and 46 year-old man underwent PCI.

Outcomes of intravascular brachytherapy for recurrent drug-eluting in-stent restenosis.

To examine the outcomes of vascular brachytherapy (VBT) for recurrent drug-eluting stents (DES) in-stent restenosis (ISR). Recurrent DES-ISR can be challenging to treat. VBT has been used with encouraging results. We report the long-term outcomes of patients with recurrent DES-ISR treated with VBT between January 2014 and September 2018 at a tertiary care institution. The main outcome was target lesion failure (TLF), defined as the composite of clinically driven target lesion revascularization (TLR), target lesion myocardial infarction (MI), and target lesion-related cardiac death. Cox proportional hazards analysis was performed to identify variables associated with recurrent TLF. During the study period, 116 patients (143 lesions) underwent VBT. Median follow-up was 24.7 (14.5-35.4) months. The incidence of TLR, target-lesion MI, and TLF was 18.9%, 5.6%,and 20.1% at 1 year, and 29.4%, 10.5%, and 32.9% at 2 years.Initial presentation with acute coronary syndrome (ACS) was independently associated with TLF (hazard ratio = 1.975, 95% CI [1.120, 3.485], p = .019). Lesions treated with intravascular ultrasound (IVUS) guidance had a lower incidence of TLR (14.3% vs. 39.6%, log-rank p = .038), and a trend toward lower incidence of TLF (19% vs. 42.6%, log-rank p = .086). VBT can improve the treatment of recurrent DES-ISR, but TLF occurs in approximately one in three patients at 2 years. Initial presentation with ACS was associated with higher TLF and the use of IVUS with a trend for lower incidence of TLF.

Relation of Plasma Xanthine Oxidoreductase Activity to Coronary Lipid Core Plaques Assessed by Near-Infrared Spectroscopy Intravascular Ultrasound in Patients With Stable Coronary Artery Disease

Previous studies reported that elevated serum uric acid level was associated with greater coronary lipid plaque. Xanthine oxidoreductase (XOR) is a rate-limiting enzyme in purine metabolism and is believed to play important roles in coronary atherosclerosis. However, the relation between XOR and coronary lipid plaque is unclear. Patients with stable coronary artery disease who underwent elective percutaneous coronary intervention under near-infrared spectroscopy intravascular ultrasound (NIRS-IVUS) guidance were prospectively included. They were divided into 3 groups according to plasma XOR activities based on a previous report: low, normal, and high. Quantitative coronary angiography and gray-scale IVUS were analyzed. The primary end point was coronary lipid plaques in a nontarget vessel assessed by NIRS-IVUS with lipid core burden index (LCBI) and maximum LCBI in 4 mm (maxLCBI4mm). Out of 68 patients, 26, 31, and 11 patients were classified as low, normal, and high XOR activity groups. Quantitative coronary angiography demonstrated that the high XOR activity group had longer lesion length, smaller minimum lumen diameter, and higher percentage of diameter stenosis in a nontarget vessel among the 3 groups. Gray-scale IVUS analysis also showed smaller lumen area in the high XOR activity group than the others. LCBI (102.1 ± 56.5 vs 65.6 ± 48.5 vs 55.6 ± 37.8, p = 0.04) and maxLCBI4mm (474.4 ± 171.6 vs 347.4 ± 181.6, 294.0 ± 155.9, p = 0.04) in a nontarget vessel were significantly higher in the high XOR group than in the normal and low groups. In conclusion, elevated XOR activity was associated with coronary lipid-rich plaque in a nontarget vessel in patients with stable coronary artery disease.

844 Intravascular Ultrasound Versus Angiography-Guided Drug-Eluting Stent Implantation: A Health Economic Analysis

There is increasing evidence that use of intravascular ultrasound (IVUS) guidance during percutaneous coronary intervention (PCI) is associated with improved clinical outcomes compared with angiography alone. However, concern regarding the cost-effectiveness of IVUS has limited use of this technology worldwide. In this study, we aimed to evaluate the cost-effectiveness of IVUS-guided PCI compared with angiography-guided PCI in patients undergoing drug-eluting stent (DES) implantation. A Markov model was constructed to compare the cost-effectiveness of IVUS-guided to angiography-guided DES implantation from the Australian healthcare system perspective. Procedure-related morbidity and mortality were estimated from the published literature. Costs were obtained from Australian sources. Outcomes of interest included costs, life-expectancy and quality-adjusted life years (QALYs). In the base case analysis, the population of interest was all-comers undergoing PCI. In sensitivity analyses, we explored whether lesion subtype affected cost-effectiveness. In the base case, IVUS-guided DES implantation was cost-effective compared to angiography-guided DES implantation. With 5% annual discounting, IVUS was associated with increased lifetime costs of AUD$799 per person and benefits of 0.10 life-years and 0.11 QALYs compared to angiography, yielding an incremental cost-effectiveness ratio of AUD$9,280/QALY gained. Analysis by lesion subtype revealed greater cost-effectiveness among patients with left main and complex coronary lesions. Results were robust to sensitivity analyses, with IVUS being cost-effective in 98% of 10,000 Monte Carlo iterations assuming a willingness-to-pay threshold of $AUD50,000/QALY gained. Use of IVUS guidance during PCI is likely to be cost-effective compared with angiography guidance alone among patients undergoing DES implantation.

Angioplasty with stenting of anomalous connections of the coronary arteries: A potential alternative to surgery. Results of the prospective ANOCOR stenting registry

Anomalous connections of the coronary arteries (ANOCOR) with an interarterial course raise therapeutic problems. Current guidelines recommend a surgical repair regardless of age for right ANOCOR with ischemic symptoms or documented myocardial ischemia. The lack of controlled studies explain some therapeutic reluctances. A percutaneous approach may provide an interesting alternative in a selected adult population. To assess the feasibility and safety of interarterial segment stenting in right ANOCOR. Stenting was proposed according to predefined criteria (age > 20 years, ischemic symptoms or documented myocardial ischemia, slit-like ostium) for patients referred to an expert group. All patients underwent selective coronary angiography and coronary computed tomography (CT). Evaluation by intravascular ultrasound (IVUS) or optical coherence tomography (OCT) was recommended. A systematic coronary CT and functional test were proposed at 6-12 months. Clinical follow-up was scheduled at 6, 12 and 60 months. Sixteen patients (mean age 52 years) were prospectively included between 2014 and 2019. Fourteen patients were symptomatic and two patients were asymptomatic with documented myocardial ischemia. Stenting was successful in all procedures with mean stent diameter of 3.4 mm, mean stent length of 25 mm, mean fluoroscopy time of 19 min, > 80% of IVUS or OCT guidance, and mean troponin at 24 hours of 0.51 μg/L. No in-hospital complication occurred. No extrinsic stent compression was observed on coronary CT follow-up. Clinical follow-up at 12 months was uneventful in all but three patients: one patient with persistent angina reported to vasospastic angina and two patients with intrastent restenosis treated by balloon angioplasty. Interarterial segment stenting appears feasible and safe. More important population and longer follow-up are needed to include this approach in a future management algorithm for patients with ANOCOR.

Effect of Intravascular Ultrasound–Guided Drug-Eluting Stent Implantation: 5-Year Follow-Up of the IVUS-XPL Randomized Trial

ObjectivesThe goal of this study was to evaluate whether the beneficial effect of use of intravascular ultrasound (IVUS) is sustained for long-term follow-up. BackgroundThe use of IVUS promoted favorable 1-year clinical outcome in the IVUS-XPL (Impact of Intravascular Ultrasound Guidance on the Outcomes of Xience Prime Stents in Long Lesions) trial. It is not known, however, whether this effect is sustained for long-term follow-up. MethodsThe IVUS-XPL trial randomized 1,400 patients with long coronary lesions (implanted stent length ≥28 mm) to receive IVUS-guided (n = 700) or angiography-guided (n = 700) everolimus-eluting stent implantation. Five-year clinical outcomes were investigated in patients who completed the original trial. The primary outcome was the composite of major adverse cardiac events, including cardiac death, target lesion–related myocardial infarction, or ischemia-driven target lesion revascularization at 5 years, analyzed by intention-to-treat. ResultsFive-year follow-up was completed in 1,183 patients (85%). Major adverse cardiac events at 5 years occurred in 36 patients (5.6%) receiving IVUS guidance and in 70 patients (10.7%) receiving angiographic guidance (hazard ratio: 0.50; 95% confidence interval: 0.34 to 0.75; p = 0.001). The difference was driven mainly by a lower risk for target lesion revascularization (31 [4.8%] vs. 55 [8.4%]; hazard ratio: 0.54; 95% confidence interval: 0.33 to 0.89; p = 0.007). By landmark analysis, major adverse cardiac events between 1 and 5 years occurred in 17 patients (2.8%) receiving IVUS guidance and in 31 patients (5.2%) receiving angiographic guidance (hazard ratio: 0.53; 95% confidence interval: 0.29 to 0.95; p = 0.031). ConclusionsCompared with angiography-guided stent implantation, IVUS-guided stent implantation resulted in a significantly lower rate of major adverse cardiac events up to 5 years. Sustained 5-year clinical benefits resulted from both within 1 year and from 1 to 5 years post-implantation. (Impact of Intravascular Ultrasound Guidance on the Outcomes of Xience Prime Stents in Long Lesions [IVUS-XPL Study]: Retrospective and Prospective Follow-Up Study; NCT03866486)

In-Hospital and 1-Year Results of Intravascular Ultrasound-Guided Versus Angiography-Guided Intervention for Type C Coronary Lesions

Background: Class C lesions are considered to have the highest degree of lesion complexity so we compared between Intravascular Ultrasound (IVUS)-guided and angiography-guided PCI for Type C coronary lesions regarding procedural success and occurrence of Major Adverse Cardiac Events (MACE). Results: Our study was conducted on patients undergoing elective PCI for type C coronary lesions. The study included 50 patients who underwent IVUS guided PCI and 50 patients who underwent angiographic guided PCI. We evaluated IVUS guidance on clinical outcomes. MACE, all-cause mortality, ST elevation infarction, and target lesion revascularization, were end points for comparison. Follow-up duration was 12 months. Adding IVUS to the procedure was associated with more procedure time but with less amount of contrast. Patients with IVUS-guided PCI underwent more direct stenting, post-dilatation, larger maximal stent diameter, and greater number of implanted stents. The IVUS guided group had significantly better final diameter stenosis but at 1-year follow up, IVUS use failed to reduce MACE significantly in comparison to angiographic guidance. In conclusion: use of IVUS is associated with lower amount of radiographic contrast used during the procedure, more procedural time, more post dilatation and less postintervention final diameter stenosis. In addition, use of IVUS in complex lesions allows optimizing PCI procedures and stent apposition. A strategy of IVUS for stent implantation in complex coronary lesions didn’t reduce the 1-year MACE rates and thus, isn’t recommended routinely

Fibroblast growth factor-2/platelet-derived growth factor enhances atherosclerotic plaque stability.

Increased immature neovessels contribute to plaque growth and instability. Here, we investigated a method to establish functional and stable neovessel networks to increase plaque stability. Rabbits underwent aortic balloon injury and were divided into six groups: sham, vector and lentiviral transfection with vascular endothelial growth factor‐A (VEGF)‐A, fibroblast growth factor (FGF)‐2, platelet‐derived growth factor (PDGF)‐BB and FGF‐2 + PDGF‐BB. Lentivirus was percutaneously injected into the media‐adventitia of the abdominal aorta by intravascular ultrasound guidance, and plaque‐rupture rate, plaque‐vulnerability index and plaque neovessel density at the injection site were evaluated. Confocal microscopy, Prussian Blue assay, Evans Blue, immunofluorescence and transmission electron microscopy were used to assess neovessel function and pericyte coverage. To evaluate the effect of FGF‐2/PDGF‐BB on pericyte migration, we used the mesenchymal progenitor cell line 10T1/2 as an in vitro model. VEGF‐A‐ and FGF‐2‐overexpression increased the number of immature neovessels, which caused intraplaque haemorrhage and inflammatory cell infiltration, eventually resulting in the plaque vulnerability; however, FGF‐2/PDGF‐BB induced mature and functional neovessels, through increased neovessel pericyte coverage. Additionally, in vitro analysis of 10T1/2 cells revealed that FGF‐2/PDGF‐BB induced epsin‐2 expression and enhanced the VEGF receptor‐2 degradation, which negatively regulated pericyte function consistent with the in vivo data. These results showed that the combination of FGF‐2 and PDGF‐BB promoted the function and maturation of plaque neovessels, thereby representing a novel potential treatment strategy for vulnerable plaques.

Percutaneous thrombectomy of mural aortic thrombus using intravascular ultrasound guidance

Mural aortic thrombus is a challenging clinical problem with significant potential complications. Particularly precarious are situations with involvement of the visceral segment of the aorta. We describe a technique for percutaneous thrombectomy of mural aortic thrombus using intravascular ultrasound to guide an angled mechanical thrombectomy catheter in conjunction with a continuous aspiration system (Indigo mechanical thrombectomy system; Penumbra, Alameda, Calif). Use of this technique in three patients with challenging cases of mural aortic thrombus is discussed. All patients were treated successfully and without complication using this technique.