Post-stent Balloon Dilatation Research Articles

Abstract 12142: Intravascular Ultrasound Guided Percutaneous Coronary Intervention Improves Acute Angiographic Results & 1-year Clinical Outcomes for Patients With Chronic Total Occlusion

Introduction: Intravascular ultrasound (IVUS) on long-term clinical outcomes in patients undergoing percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) is not well established. This study aimed to evaluate IVUS-guided compared to angiography-only-guided CTO-PCI on acute angiographic result and 1-year clinical outcomes. Hypothesis: The application of IVUS in CTO-PCI could improve acute angiographic results and 1-year clinical outcomes for all-comers CTO patients. Methods: We analysed 528 consecutive patients undergoing CTO-PCI at a university affiliated hospital in Hong Kong from February 2009 to December 2016. Baseline characteristics, procedural characteristics, and 1-year clinical outcomes including cardiac death, non-fatal myocardial infarction (MI), target lesion revascularization (TLR), and composite target lesion failure (TLF) were evaluated. The use of IVUS, and the choice of PCI devices including plain old balloon angioplasty (POBA), bare metal stent (BMS), and drug eluting stent (DES), were at the discretion of the operator. Propensity score matching (PSM) was performed to reduce treatment selection bias and potential confounding factors. Results: 275 patients underwent 288 angiography-only-guided and 253 patients underwent 268 IVUS-guided CTO-PCI. IVUS-guided CTO-PCI was associated with higher procedural success compared to angiography-only-guided CTO-PCI (77.5% vs. 55.3%, p<0.01). DES were used more often in the IVUS-guided CTO-PCI group (85.3% vs. 65.6%, p<0.01) while BMS were used less in IVUS-guided CTO-PCI group (9.3% vs. 26.1%). After PSM for successful CTO stented patients, angiography-IVUS guidance was associated with more post stent balloon dilatation (84.7% vs. 56.3%, p<0.01), lower incidence of >20% residual stenosis (2.2% vs. 10.8%, p<0.01), longer total stent length (44.16±23.88mm vs. 33.52±18.90mm, p<0.01), and larger final angiographic stented diameter (3.12±0.63mm vs. 2.94±0.48mm, p<0.01). IVUS guided CTO-PCI was associated with lower 1-year TLF rates (3.0% vs. 10.0%, p=0.01). Conclusions: The use of IVUS was associated with higher success rates, more aggressive post-dilatation and better 1-year clinical outcomes compared to angiography-only guided CTO-PCI.

Outcome of Wingspan Stent Using Aggressive Post-stent Balloon Dilation for Intracranial Atherosclerosis Stenosis.

Background: Wingspan stent has gained interest for better long-term outcomes for intracranial atherosclerosis disease (ICAD). However, in-stent restenosis still presents as a problem and may cause postoperative neurological events. We aimed to find a way to prevent in-stent restenosis.Method: Patients with stenosis >70% ICAD were treated with wingspan stent and were retrospectively reviewed. The patients were separated into two groups: one with post-dilation and the other without post-dilation. The outcomes of wingspan stenting were compared immediately after the surgery and at a 1-year follow-up.Results: Overall, 28 patients were included for analysis, with 15 patients undergoing post-dilation and 13 patients not undergoing the procedure. The extent of stenosis was significantly lower in the post-dilation group than in the no post-dilation group, both immediately after the surgery (14.8 ± 10.2 vs. 28.5 ± 14.5%, p < 0.01) and at 1-year follow-up (25.8 ± 18.0 vs. 50.1 ± 23.2%, p < 0.01). The post-dilation method immediately expanded the stent diameter (2.89 ± 0.48 vs. 3.05 ± 0.44 mm, p < 0.001), and the diameter still increased at 1-year follow-up (3.05 ± 0.44 vs. 3.12 ± 0.43 mm, p < 0.01) due to the self-expandable property of the wingspan. Similarly, in the no post-dilation group, the stent size was also increased (2.70 ± 0.67 vs. 2.80 ± 0.64 mm, p < 0.01). However, at 1-year follow up, the luminal diameter was stationary in the post-dilation group (2.36 ± 0.73 vs. 2.46 ± 0.82 mm, p = 0.88) and decreased in the no post-dilation group (2.24 ± 0.56 vs. 1.60 ± 0.79 mm, p < 0.01). The periprocedural complication rate was similar between the groups.Conclusion: The post-dilation method can be feasibly performed and can offer better stent expansion and apposition in the wingspan system. By applying this technique, we might prevent in-stent restenosis and improve neurological outcomes.

What should be the Optimal Carotid Stent Opening Rate Without Post-Dilation?

BackgroundThere is not a widely accepted optimal rate of stent opening in patients underwent carotid artery stenting. In this study we evaluated the effect of carotid stent opening rate (CSOR) without performing post-dilation on in-hospital and long-term outcomes. MethodsA total of 825 patient patients underwent carotid artery stenting without post-dilation enrolled to the study. The patients divided into two groups according to their final CSOR (50% ≤ Post-stent deployment (SD) <80% and 80% ≤ Post-SD ≤ 100%). In-hospital and 3-year outcomes were compared between the groups. ResultsDuring hospitalization, the rate of ipsilateral stroke, major stroke and transient ischemic attacks were similar between the groups (respectively; 6.2% vs. 4.1, P = 0.190; 1.5% vs. 1.8, P = 0.811; 1.5% vs. 1.9%, P = 0.683). The 3-year Kaplan-Meier overall survival rates for the first and second groups were 87.6% and 84.4%, respectively (log rank test P = 0.426). The 3-year Kaplan-Meier overall cumulative ipsilateral stroke rates for the first and second groups were 88.0% and 88.6%, respectively (log rank test P = 0.409) ConclusionOur study demonstrated that a CSOR higher than 50% without performing a post-dilation might be an effective therapeutic approach since there was not a significant difference regarding outcomes between the patients with a 50% ≤ Post-SD <80% and 80% ≤ Post-SD ≤ 100%. The need for post-stent balloon dilation might have been eliminated due to subsequent stent self-expansion.

Long-term Outcome of Angioplasty Using aWingspan Stent, Post-Stent Balloon Dilation and Aggressive Restenosis Management for Intracranial Arterial Stenosis.

To investigate the long-term outcome of stent angioplasty for symptomatic severe intracranial artery stenosis. In this study 95 consecutive patients with intracranial atherosclerotic stenosis (>70%) underwent stent angioplasty using Wingspan stents. The primary endpoints were stroke or death within 30days of the procedure and subsequent stroke attributed to the stented vessel. Disabling stroke was defined as stroke with amodified Rankin scale > 3.Secondary endpoints included transient ischemic attacks, contralateral stroke, nonstroke death, and other events. Patients underwent prestent balloon dilation with or without poststent balloon dilation, close restenosis follow-up, and selective retreatment, as required. The mean follow-up duration was 34.9 ± 23.3months. Primary endpoint events occurred in 23% of the patients. The median infarction volume was 2.6ml, and 11 (68%) of 16 infarctions were <5ml in volume. Disabling stroke occurred in 3% of patients. The primary endpoint rates were 17.9% within 30days and 2.1% from 30days to 1year. Secondary endpoint events occurred in 27.3% of the patients. Mean stenosis was reduced from 76.8 ± 6.1% to 7.5 ± 13.4%. Of 80patients who underwent angiographic follow-up, 11 (14%) experienced restenosis (≥50%) and 7 (9%) exhibited restenosis-related symptoms of transient ischemic attack. The rate of symptomatic restenosis was significantly higher in patients who underwent prestent balloon dilation alone than in patients who underwent prestent and poststent balloon dilation (p = 0.016). The postprocedural stroke rate was similar to that observed in the SAMMPRIS study. Symptomatic restenosis may be reduced by poststent dilation, close angiographic follow-up, and retreatment.

Carbon-coated self-expandable stents in patients with atherosclerotic iliac artery disease.

The aim of this study was to evaluate the safety and effectiveness of carbon-coated self-expandable stents in the revascularization of atherosclerotic iliac artery lesions. Between January 2012 and June 2016 54 carbon-coated self-expandable stents (Easy HiFlype and Easy Flype; manufactured by CID S.p.A., a member of Alvimedica Group, Istanbul, Turkey) in 40 patients were implanted in our Center. Early and 2-year outcomes have been evaluated in terms of major morbidity, mortality, primary patency, primary assisted patency, secondary patency, absence of target lesion restenosis (TLR), healing of the lesions/relief of symptoms, and limb salvage. The patients were predominantly males (32/40, 80%) with a mean age of 71 years (range 46-94). One patient (2.5%) had a documented nickel allergy. Mean duration of follow-up was 13.9 months (range 1-48). At 30 days no patient died and 1 patient underwent surgical revision of percutaneous femoral access. The estimated 2-year primary patency, primary assisted patency, secondary patency, absence of TLR, and limb salvage were 92.8%, 93.1%, 95.7%, 79.5%, and 100%, respectively. At univariate analysis none of the pre- or intra-operative factors significantly affected the primary and primary assisted patency rates. Secondary patency was significantly affected by absence of post-stent balloon dilatation (P=0.003). Absence of TLR was significantly affected by age more than 80 years (P=0.01) and common iliac artery lesions (P=0.02). These significances were confirmed at Cox regression analysis. Use of carbon-coated self-expandable stents in atherosclerotic iliac lesions was safe and effective. At 2 years, the patency rates and the absence of TLR were encouraging. Post-stent balloon dilatation should be recommended in all cases. Older patients and common iliac artery lesions were risk factors for restenosis in the mid-term period.

Effect of Adjunct Balloon Dilation after Long Everolimus-eluting Stent Deployment on Major Adverse Cardiac Events.

Background and ObjectivesThe effectiveness of adjunct balloon dilation after drug-eluting stent (DES) deployment has not been sufficiently evaluated. We evaluated whether adjunct balloon dilation was associated with a reduction in major adverse cardiac events (MACEs) after long everolimus-eluting stents (EESs) implantation.Subjects and MethodsDrawing from 2 randomized trials, a total of 1,672 patients treated with long EES were analyzed. Of 1,672 patients, 1,061 patients (64%) received post-stent adjunct balloon dilation. MACE, defined as a composite of cardiac death, myocardial infarction, and target-lesion revascularization (TLR), was compared between patients who received post-stent adjunct balloon dilation and patients who did not in 595 propensity score-matched pairs.ResultsFor the matched population, MACE occurred in 29 patients (4.9%) who received adjunct balloon dilation and in 29 patients (4.9%) who did not (hazard ratio [HR], 1.01; 95% confidence interval [CI], 0.60–1.69; p=0.972). However, significant interactions were observed among the subgroups for clinical presentation and vessel size. Adjunct balloon dilation was more favored within the subset of patients with stable angina vs. the subset of patients with acute coronary syndrome (p for interaction=0.037), and within the subset of lesions with small vessel diameter (reference vessel diameter [RVD] <3 mm) vs. the subset of lesions with larger vessel diameter (RVD ≥3 mm; p for interaction=0.027).ConclusionAdjunct balloon dilation was not associated with MACE reduction at 1 year among patients requiring long EES implantation. However, post-stent adjunct balloon dilation may be necessary for patients requiring long EES implantation who present with stable angina or for lesions with small vessel diameters.

Outcomes with bioabsorbable vascular scaffolds versus everolimus eluting stents: Insights from randomized trials

BackgroundBioresorbable vascular scaffolds (BVS) have been shown to be non-inferior to second generation drug eluting stents in recent clinical trials. However, the trials were not powered for individual endpoints and there is concern for increased device thrombosis with BVS. MethodsWe performed a systematic search for randomized clinical trials of BVS versus EES. Efficacy outcomes were target lesion revascularization (TLR) and target vessel revascularization (TVR). Safety outcomes were death, myocardial infarction (MI), and device thrombosis. Meta-regression analyses were performed to evaluate the association of device thrombosis with clinical characteristics (percent patients with acute coronary syndrome) and device deployment characteristics (percent with post stent balloon dilation). ResultsWe identified six RCTs that enrolled 3738 patients. When compared with EES, BVS was associated with similar risk of TLR (RR=1.06; 95% CI 0.73–1.54), TVR (RR=1.00; 95% CI 0.74–1.35), death (RR=1.11; 95% CI 0.53–2.33) and cardiovascular death (RR=1.39; 95% CI 0.43–4.43) but numerically higher MI (RR=1.35; 95% CI 0.98–1.86) and definite or probable device thrombosis (RR=2.11; 95% CI 0.99–4.47). In a sensitivity analysis using the Peto odds ratio method, the risk of definite or probable device thrombosis was significantly increased (OR=2.08; 95% CI 1.06–4.08; P=0.03), although this did not reach statistical significance in four other models. The risk of definite or probable device thrombosis with BVS was reduced in trials where more post stent balloon dilation was used and in patients without acute coronary syndrome. Moreover, trial sequential analysis showed that the cumulative z-curve crossed the conventional boundary and not the trial sequential boundary, indicating lack of robust data to support increased definite or probable device thrombosis with BVS. ConclusionsIn patients with noncomplex obstructive coronary disease, BVS are comparable to EES for most efficacy and safety outcomes except for a numerical increase in device thrombosis and MI. The risk of the latter outcomes was mitigated in trials where more post stent balloon dilation was used and in patients without acute coronary syndrome. Moreover, with only 3738 patients, the trials are underpowered to detect a difference in rare events such as device thrombosis.

Association Between Intraprocedural Thrombotic Events and Adverse Outcomes After Primary Percutaneous Coronary Intervention for ST-Segment Elevation Myocardial Infarction (a Harmonizing Outcomes With RevasculariZatiON and Stents in Acute Myocardial Infarction [HORIZONS-AMI] Substudy)

The present study sought to determine the extent to which adverse angiographic events encountered during percutaneous coronary intervention for ST-segment elevation myocardial infarction (STEMI) are associated with adverse clinical outcomes. Patients with STEMI represent a cohort at particularly high risk of intraprocedural thrombotic events (IPTEs). The overall frequency and implications of IPTEs occurring in patients with STEMI have not been systematically quantified in previous studies. A total of 3,163 patients undergoing primary percutaneous coronary intervention with stent implantation for STEMI in the Harmonizing Outcomes with RevasculariZatiON and Stents in Acute Myocardial Infarction (HORIZONS-AMI) trial underwent detailed frame-by-frame core laboratory angiographic analysis to assess IPTEs. The clinical outcomes at 30 days were compared between the patients with and without IPTEs. IPTEs, defined as the development of new or increasing thrombus, abrupt vessel closure, no reflow, slow reflow, and distal embolization at any point during the procedure, occurred in 386 patients (12.2%). The independent predictors of IPTE were thrombus at baseline, lesion length, and randomization to bivalirudin; the patients with IPTEs were also more likely to receive bailout glycoprotein IIb/IIIa inhibitors and unplanned thrombectomy. Compared with patients without IPTEs, the patients with IPTEs had higher 30-day rates of composite major adverse cardiovascular events (death, myocardial infarction, ischemic target vessel revascularization, and stroke; 7.8% vs 4.2%, p = 0.002), major bleeding not related to coronary artery bypass grafting (11.8% vs 6.5%, p <0.001), and all-cause death (4.2% vs 1.8%, p = 0.002). On multivariate analysis, IPTEs were independently associated with 30-day major adverse cardiovascular events, major bleeding, and death. In conclusion, the development of IPTEs in patients undergoing primary percutaneous coronary intervention for STEMI was associated with subsequent adverse outcomes, including major adverse cardiovascular events, major bleeding, and death. Additional studies of strategies to decrease the occurrence of IPTEs are warranted.

Longitudinal deformation – Price we pay for better deliverability of coronary stent platforms

Coronary stents, especially drug eluting stents (DES), have revolutionized the practice of interventional cardiology. Newer stents are manufactured by altering basic design characteristics to tackle complex coronary morphologies more effectively. Alteration in one particular attribute might affect other attributes adversely. Even though, reduction in the number and alteration of the orientation of the connectors improves the stent flexibility and deliverability, it adversely decreases the axial strength of the stent with resulting longitudinal stent deformation. A 67 year old female underwent percutaneous coronary intervention for a mid left anterior descending artery stenosis with a 2.75 × 16 mm Promus Element stent (Boston Scientific, Natick, Massachusetts). The stent got longitudinally distorted during post-stent balloon dilatation which was effectively managed with further dilatation with non-compliant balloon.

Angiographic and intravascular ultrasound follow up of paclitaxel‐ and sirolimus‐eluting stent after poststent high‐pressure balloon dilation: From the poststent optimal stent expansion trial

The aims of this study were to identify the efficacy of optimal stent expansion (OSE) according to the Multicenter Ultrasound Stenting in Coronaries Study (MUSIC Study) criteria in drug-eluting stent (DES) and compare paclitaxel-eluting stent (PES) to sirolimus-eluting stent (SES). Although poststent high-pressure balloon dilatation is proposed after bare metal stent implantation according to OSE, defined by the criteria of the MUSIC Study, very little data are available in DES. Two hundred fifty patients (M:F = 149:101; age, 61.5 ± 9.2 years) who underwent 9-month follow-up angiography in the Poststent Optimal Stent Expansion Trial (POET) were included in this study. We assessed angiographic in-stent restenosis (ISR) and neointima volume (NV) using IVUS at 9 months. At 9-month follow up, there were no significant differences in ISR and NV index (NV/stent length, mm(2) ) between patients with and without OSE. However, the rate of ISR and NV index were higher in PES [ISR: 18 (13.7%) and 4 (3.4%), P = 0.004; NV index: 1.02 ± 0.99 mm(2) and 0.21 ± 0.37, P < 0.001 in PES and SES]. OSE according to the MUSIC Study criteria was not related to ISR and NV in the DES era but PES had a significantly higher ISR rate and NV than SES after poststent high-pressure balloon dilatation.

A comparison of clinical outcomes in STEMI patients treated with primary angioplasty with and without post stent balloon dilatation

A comparison of clinical outcomes in STEMI patients treated with primary angioplasty with and without post stent balloon dilatation

後拡張を省いた頚動脈ステント留置術による狭窄率の遷延性改善効果

【目的】後拡張を省いた頚動脈ステント留置術（CAS）における狭窄率改善効果を検討した．【方法】 CAS後にfollowup脳血管造影検査（平均13.7ヵ月，0.5～24ヵ月）が可能であった10例11病変を対象に，術前，術直後およびfollowup時の残存狭窄率を検討した．また，プラーク内石灰化の有無による狭窄改善率の違いについて検討した．【結果】術前狭窄率は87.3±11.0%（mean±SD），術直後の狭窄率は30.1±5.7%（mean±SD）であった．Followup脳血管造影時の平均残存狭窄率は12.3±16.1%（mean±SD）と改善した（P<0.003）．石灰化を含む病変の残存狭窄率は術直後29.0±5.2%からfollowup時24.3±9.5%への改善に留まったのに対し，非石灰化病変では28.2±6.1%から7.1±9.9%へと著明に改善した．【結語】後拡張を省いたCASでも，特に非石灰化病変において経時的な狭窄率改善が期待できる．

Intravascular Ultrasound Evaluation of Optimal Drug-Eluting Stent Expansion After Poststent Balloon Dilation Using a Noncompliant Balloon Versus a Semicompliant Balloon (from the Poststent Optimal Stent Expansion Trial [POET

The impact of type of balloon such as noncompliant (NC; Quantum) or semicompliant (SC; Maverick(2)) used after stent dilation on optimal stent expansion (OSE) has not been established for drug-eluting stents (DESs). We conducted a prospective multicenter, randomized study to compare NC with SC balloons after stent balloon dilatation. A total of 301 patients (127 men, 83 women, 62 +/- 9 years of age) treated with a DES (sirolimus-eluting stent [SES], n = 152; paclitaxel-eluting stent, n = 149) were included. OSE followed the definition of the Multicenter Ultrasound Stenting in Coronaries (MUSIC) study. The primary end point was the incidence of OSE using intravascular ultrasound according to type of balloon. Baseline characteristics of each group showed no significant differences. OSE in the SC balloon group was achieved at higher rates than the NC balloon group (53 +/- 35%, vs 73 +/- 48%, p = 0.022 in all stents; 25 +/- 33%, vs 36, 48%, p = 0.051 in SESs). However, any differences in the achievement of OSE between the NC and SC balloon groups were not present in paclitaxel-eluting stents. In conclusion, despite postadjuvant balloon inflations with high pressures, underexpansion of the DES was seen commonly. Between the 2 types of balloon for adjuvant dilation after DES implantation, same-size SC balloons could be more useful for obtaining OSE than NC balloons, especially in SESs.

Local paclitaxel delivery after coronary stenting in an experimental animal model

The goal of this study was to test the safety and efficacy of local paclitaxel delivery via a newly designed application catheter in an experimental animal study. Drug-eluting stents reduce restenosis in comparison to bare-metal stents. The drug-eluting polymer, however, may exert potential thrombogenic and inflammatory effects. A catheter-based local paclitaxel delivery offers further advantages, particularly a homogenous drug transfer into the vessel wall and a pharmacotherapy of the stent edges. In 30 pigs, both bare-metal stent (3.0 x 13 mm) implantation and balloon angioplasty were performed. Ten pigs received subsequent local delivery of paclitaxel-solution via a newly designed catheter (Genie, ACROSTAK corp., Switzerland), 10 animals served as a sham group and received vehicle (0.9% NaCl solution) and 10 animals were used as a control group. All animals were treated with aspirin and clopidogrel to prevent stent thrombosis. After final angiography the vessels were excised 42 days after intervention and prepared for histological and histomorphometric analysis. All coronary arteries showed complete endothelialization 42 days following treatment. Paclitaxel treatment led to a marked reduction of neointimal proliferation either post stent implantation (neointimal area: 1.04 +/- 0.10 mm(2) vs. 2.37 +/- 0.23 mm(2), p < 0.001) or post balloon dilatation (neontimal area: 0.35 +/- 0.14 mm(2), vs. 0.68 +/- 0.24 mm(2), p < 0.01). There were no significant angiographic or histomorphometric differences between the control and the sham group. In both paclitaxel groups neither angiographic edge phenomena nor a significant histomorphometric inflammatory response were found in the treated vessel segments. In conclusion, the local application of paclitaxel via the Genie catheter is safe and effective to significantly reduce the proliferative response post-stent implantation or balloon dilatation in an experimental animal model.

Slow-Flow Phenomenon During Carotid Artery Intervention With Embolic Protection Devices: Predictors and Clinical Outcome

The purpose of this research was to define the predictors of the "slow-reflow" phenomenon during carotid artery intervention with filter-type embolic protection devices (EPDs) and to determine its prognostic significance. During carotid artery intervention using filter-type EPDs, we have observed cases in which there is angiographic evidence of a significant reduction in antegrade flow in the internal carotid artery proximal to the filter device, termed "slow-flow." The predictors of this phenomenon and its prognostic significance are unknown. Using a single-center prospective carotid intervention registry, patients with slow-flow were compared to patients with normal flow during carotid intervention with respect to clinical, procedural, and lesion characteristics, and the 30-day incidence of death and stroke. A total of 414 patients underwent 453 carotid artery interventions using EPDs. Slow-flow occurred in 42 patients (10.1%) undergoing 42 carotid interventions (9.3%), and most commonly occurred after post-stent balloon dilatation (71.4%). Multivariate logistic regression analysis identified the following predictors of slow-flow: recent history (<6 months) of stroke or transient ischemic attack (odds ratio [OR] 2.8, 95% confidence interval [CI] 1.4 to 5.6, p = 0.004), increased stent diameter (OR 1.4, 95% CI 1.02 to 1.94, p = 0.044), and increased patient age (OR 1.05, 95% CI 1.01 to 1.09, p = 0.025). Among patients with slow-flow, the 30-day incidence of stroke or death was 9.5% compared to 2.9% in patients with normal flow (chi-square = 4.73, p = 0.03). This difference was driven by the disparity in the 30-day incidence of stroke (9.5% vs. 1.7%). Slow-flow during carotid intervention with EPDs is a frequent event that is associated with an excess risk of periprocedural stroke. The association of the phenomenon with clinically symptomatic carotid lesions and use of larger stent diameters suggests that embolization of vulnerable plaque elements may play a pathogenic role.

902-3 The Impact of Intravascular Ultrasound (IVUS) on Post-Stent Deployment Balloon Dilatation Strategies

To evaluate the impact of IVUS on post-stent deployment balloon dilatation strategies, we compared the quantitative angiographic results in 1044 lesions undergoing native vessel (N = 415) or saphenous vein graft (SVG) (N = 629) stent implantation using atubular slotted (JJIS) stent design. Comparison groups include the New Approaches to Coronary Intervention Registry (NACI, 1990-93), Washington Hospital Center (WHC) Stent Registry (native vessel, 1990-1992; SVG, 1992-94) and 2 IVUS-guided (complete stent ap-position, symmetry, and expansion) stent deployment protocols (Colombo in native vessels, 1993; Reduced Anticoagulation After Vein Graft Stent [RAVES] Study, 1993-4). Cineangiograms were analyzed at a central Core Laboratory using identical angiographic methodology (ImageComm). Balloon: artery ratios (BAR) were measured using the mean balloon diameter. Native Vessels SVGs NACI WHC Colombo NACI WHC RAVES Number Lesions 154 140 121 152 443 34 Reference, mm 3.26 3.26 3.09 3.47 3.68 3.51 % Adjunct Balloon 46 74 100 61 58 100 Balloon: Artery Ratio 1.10 1.08 1.28 1.09 1.12 1.23 MLD-Pre, mm 0.90 0.90 1.02 1.03 1.25 1.27 Post-Stent, mm 2.74 2.58 - 2.80 2.88 3.03 Final, mm 2.90 2.90 317 3.07 3.41 3.53 Δ &gt;MLD alter balloon* 0.38 0.26 - 0.45 0.44 0.73 % Stenosis — Pre 72 73 67 70 66 64 Post-Stent 16 22 - 20 20 14 Final 12 12 - 2 14 7 - 7 MLD = minimal lumen diameter We conclude that 1) use of adjunct PTCA after stent deployment has increased, based on incomplete stent deployment identified by IVUS (despite an acceptable angiographic result); 2) BARs were higher after IVUS-guided stent deployment; and 3) IVUS-guided stent deployment result in a very low (-2% in native arteries, -7% in SVGs) final % stenosis. Assessment of the potential risk for angiographic complications using these aggressive balloon strategies must be periormed.