Vascular Closure Devices Attenuate Femoral Access Complications of Primary Percutaneous Coronary Intervention.

OBJECTIVES: To compare severe complications related to radial access and those related to femoral access using vascular closure devices for patients undergoing primary percutaneous coronary intervention (PCI). BACKGROUND: Femoral artery access is still used for acute myocardial infarction management; studies comparing state-of-the-art radial and femoral techniques are required to minimize bias regarding the outcomes associated with operator preferences. METHODS: We performed a randomized study comparing radial access with a compression device and anatomic landmark-guided femoral access with a hemostatic vascular closure device. The severe complication rates related to the access site were assessed until hospital discharge. A meta- analysis including studies with comparable populations reporting severe bleeding and major adverse cardiovascular event rates was performed. RESULTS: A total of 250 patients were included who underwent PCI between January 2016 and February 2019. Mean age was 61.5 ± 12.2 years, 73.2% were men, and 28.4% had diabetes. There were no differences between groups or in vascular access-related severe complication rates (8.0% for femoral group vs 5.6% for radial group; P=.45). Although radial access was associated with decreased vascular complications related to the access site when compared with the femoral approach (relative risk [RR], 0.64; 95% confidence interval [CI], 0.43-0.95), the meta-analysis did not show an impact on severe bleeding (RR, 0.74; 95% CI, 0.37-1.46) or severe cardiovascular adverse events (RR, 0.69; 95% CI, 0.30-1.58). CONCLUSIONS: Compliance with femoral artery puncture techniques and routine use of a vascular closure device promoted low severe complication rates.

Twelve-month clinical and imaging outcomes of the uncaging coronary DynamX bioadaptor system.

AIMS: We aimed to assess the safety and efficacy of the DynamX Novolimus-Eluting Coronary Bioadaptor System, a novel device that initially acts as a second-generation drug-eluting stent, but after six months frees the vessel through uncaging elements. METHODS AND RESULTS: This multicentre study enrolled 50 patients with single de novo lesions. In-device acute lumen gain was 1.61±0.34 mm, and device and procedure success was 100%. Up to 12 months, two target lesion failures occurred: both were cardiac deaths (day 255 and day 267 post procedure). No definite or probable device thrombosis was observed. Mean late lumen loss was 0.12±0.18 mm in-device and 0.11±0.16 mm in-segment. Per intravascular ultrasound, the mean device area and mean vessel area increased significantly by 5% and 3%, respectively, while the mean lumen area was maintained. Stationary optical coherence tomography in seven patients demonstrated restoration of cyclic pulsatility, with an approximate lumen area variance of 11% between systole and diastole. CONCLUSIONS: The DynamX bioadaptor showed drug-eluting stent-like acute performance and safety and efficacy up to one year. Positive remodelling with an increase of vessel and device area while maintaining the mean lumen area was demonstrated. Long-term follow-up and randomised trials are required to assess the benefit of this device on events beyond one year.

Cardiovascular Risk Stratification for Patients Treated With Drug-Eluting Stents: Development and Validation of the DESIRE Score.

BACKGROUND: We sought to develop a risk score to estimate the risk of major adverse cardiac event (MACE) occurrence during the in-hospital and long-term follow-up periods after percutaneous coronary intervention (PCI) with drug-eluting stent (DES) implantation. METHODS: This score was developed and validated in a single-center database encompassing all consecutive patients treated with DES between 2007 and 2014 (n = 4061). For the development of the score, we analyzed all patients treated between January 2007 and December 2012 (n = 2863) while the validation was conducted in a cohort treated between January 2013 and December 2014 (n = 1198). MACE was defined as the combination of cardiovascular death, myocardial infarction, and ischemia- driven target-lesion revascularization. Different stratification models were developed for the in-hospital (logistic regression) and late follow-up score (Cox model). RESULTS: In-hospital scores ranged from 0 to 37 points and comprised: (a) age; (b) previous coronary artery bypass grafting (CABG); (c) acute coronary syndrome; (d) peripheral vascular disease; (e) treatment of saphenous vein graft; (f) long lesions; (g) small vessels; (h) multivessel disease; and (i) thrombus. The late scores ranged from 0 to 45 points and comprised: (a) previous CABG; (b) diabetes mellitus; (c) acute coronary syndrome; (d) multivessel disease; (e) small vessels; (f) ejection fraction <40%; and (g) treatment of saphenous vein graft. Patients were stratified into low-risk, moderate-risk, and high-risk groups. Both scores had close to 70% accuracy for predicting MACE. CONCLUSION: The present score was developed and validated based on contemporary models for assessing periprocedural and long-term MACE risk post PCI, throughout the full spectrum of patient risk, and important patient subgroups.

Predictors of long-term adverse events after Absorb bioresorbable vascular scaffold implantation: a 1,933-patient pooled analysis from international registries.

AIMS: The aim of this study was to investigate the predictors of long-term adverse clinical events after implantation of the everolimus-eluting Absorb bioresorbable vascular scaffold (BVS). METHODS AND RESULTS: We pooled patient-level databases derived from the large-scale ABSORB EXTEND study and five high-volume international centres. Between November 2011 and November 2015, 1,933 patients underwent PCI with a total of 2,372 Absorb BVS implanted. The median age was 61.0 (IQR 53.0 to 68.6) years, 24% had diabetes, and 68.2% presented with stable coronary artery disease. At a median follow-up of 616 days, MACE occurred in 93 (4.9%) patients, all-cause death in 36 (1.9%) patients, myocardial infarction in 47 (2.5%) patients, and target vessel revascularisation in 72 (3.8%) patients. Definite or probable scaffold thrombosis occurred in 26 (1.3%) patients. On multivariable logistic regression analysis, acute coronary syndromes (hazard ratio [HR] 2.79, 95% confidence interval [CI]: 1.47 to 5.29; p=0.002), dyslipidaemia (HR 1.43, 95% CI: 1.23 to 1.79; p=0.007), scaffold/reference diameter ratio >1.25 (HR 1.49, 95% CI: 1.18 to 1.88; p=0.001), and residual stenosis >15% (HR 1.67, 95% CI: 1.34 to 2.07; p<0.001) were independent predictors of MACE, whereas the use of intravascular imaging was independently associated with a reduction in MACE (HR 0.13, 95% CI: 0.06 to 0.28; p<0.001). CONCLUSIONS: Optimal Absorb BVS implantation and the use of intravascular imaging guidance are associated with lower rates of adverse events at long-term follow-up.

Impact of PCI Appropriateness in the Long-Term Outcomes of Consecutive Patients Treated With Second-Generation Drug-Eluting Stents.

BACKGROUND: Appropriate use criteria (AUC) for coronary revascularization were developed to deliver high-quality care; however, the prognostic impact of these criteria remains unclear. We sought to assess the outcomes of patients treated with second-generation drug-eluting stent (DES) classified according to the updated American College of Cardiology Foundation/American Heart Association/Society for Cardiac Angiography and Intervention AUC for percutaneous coronary intervention (PCI). METHODS: Between January 2012 and December 2013, a total of 1108 consecutive patients treated only with second-generation DES were categorized according to the AUC in three groups, using the new proposed terminology: appropriate ("A"); uncertain ("U"); and inappropriate ("I"). Major adverse cardiac event (MACE, defined as cardiac death, non-fatal myocardial infarction, and ischemia-driven target-lesion revascularization) and stent thrombosis up to 3 years were compared. RESULTS: PCI was categorized as A in 33.8%, U in 46.8%, and I in 19.4% of all cases. PCI-A patients had a higher prevalence of acute coronary syndromes, while PCI-I involved the treatment of more diabetics and patients with stable coronary disease. There were no differences in procedural complications among the three groups, with comparable rates of in-hospital MACE (9.3% for A vs 9.0% for U vs 7.0% for I; P=.70) and 2-year MACE (13.9% for A vs 9.0% for U vs 8.6% for I; P=.40). In the multivariable analysis, AUC classification was not associated with adverse outcomes. CONCLUSIONS: In this contemporary cohort of patients treated with second-generation DES implantation, AUC did not impact 3-year clinical follow-up.

One-year clinical outcomes of patients treated with everolimus-eluting bioresorbable vascular scaffolds versus everolimus-eluting metallic stents: a propensity score comparison of patients enrolled in the ABSORB EXTEND and SPIRIT trials.

AIMS: We sought to compare the outcomes of low/moderate complexity patients treated with the Absorb BVS from the ABSORB EXTEND trial with patients treated with the XIENCE everolimus-eluting stent (EES), using propensity score (PS) matching of pooled data from the SPIRIT trials (SPIRIT II, SPIRIT III, SPIRIT IV) and the XIENCE V USA trial. METHODS AND RESULTS: ABSORB EXTEND was a prospective, single-arm, open-label clinical study in which 812 patients were enrolled at 56 sites. This study allowed the treatment of lesions ≤28 mm in length and with a reference vessel diameter of 2.0-3.8 mm (as assessed by online QCA). The propensity score was obtained by fitting a logistic regression model with the cohort indicator as the binary outcome and other variables as the predictor variables. At one-year clinical follow-up, there was no statistical difference between groups with regard to MACE (5.0% vs. 4.8%, p=0.83), target lesion failure (5.0% vs. 4.7%, p=0.74), ischaemia-driven target vessel revascularisation (2.3% vs. 3.0%, p=0.38) and device thrombosis (1.0% vs. 0.3%, p=0.11). Myocardial infarction was higher with Absorb (3.3% vs. 1.5%, p=0.02), at the expense of periprocedural CK-MB elevation. Independent predictors of MACE among patients receiving Absorb BVS were treatment of multivessel disease, insulin-dependent diabetes and performance of post-dilation. CONCLUSIONS: At one-year follow-up, propensity score-matched analysis demonstrated that the clinical safety and effectiveness of Absorb are comparable to those of XIENCE EES among non-complex patients treated with PCI.

Long-term clinical follow-up of patients undergoing percutaneous alcohol septal reduction for symptomatic obstructive hypertrophic cardiomyopathy.

BACKGROUND: Alcohol septal ablation (ASA) is an alternative treatment for symptomatic hypertrophic obstructive cardiomyopathy (HOCM) patients refractory to pharmacological therapy. We sought to evaluate the immediate and long-term incidence of death and changes in life quality in a consecutive cohort submitted to ASA. METHODS AND RESULTS: Between October 1998 and December 2013, a total of 56 patients (mean age 53.2 ± 15.5) with symptomatic refractory HOCM were treated with ASA and followed during 15 years (mean 8 ± 4 years). There were 7 (12.5%) deaths, 2 (3.6%) being of cardiac cause. The Kaplan-Meier survival probability estimate was 96.4% at 1 year, 87.7 at 5 years and 81.0% at 12 years post-ASA. Significant improvement was observed in life quality assessed by DASI index and NYHA functional class as well as in the left ventricle outflow tract (LVOT) gradient reduction (from 92.8 ± 3.3 mm Hg to 9.37 ± 6.7 mm Hg, P < 0.001) and septum thickness (from 23.9 ± 0.6 mm to 12.9 ± 1.0 mm, P < 0.001). Only one patient (1.7%) required permanent pacemaker immediately after ASA. During follow-up, one patient had a repeated ASA, three patients underwent myectomy and other four required ICD/pacemaker. In the multivariate model only post-ASA LVOT residual gradient and left ventricle mass were associated with worse prognosis. CONCLUSIONS: In this long-term clinical follow-up without losses, ASA was effective in improving quality of life and NYHA functional class, with relatively low mortality and very low need for immediate permanent pacemaker implantation. © 2016 Wiley Periodicals, Inc.

Impact of post-dilation on the acute and one-year clinical outcomes of a large cohort of patients treated solely with the Absorb Bioresorbable Vascular Scaffold.

AIMS: We sought to determine the impact of post-dilation (PD) on clinical outcomes in a large cohort of patients treated only with the Absorb Bioresorbable Vascular Scaffold (BVS). METHODS AND RESULTS: We evaluated all consecutive patients enrolled in the multicentre, single-arm ABSORB EXTEND study up to June 2013. The study allowed treatment of up to two coronaries (diameter 2.0 to 3.8 mm) and the use of overlapping (lesion length ≤28 mm). Patients with severe lesion calcification/tortuosity were excluded. Aggressive lesion predilation (balloon to artery ratio of 0.9-1.0) was mandatory, and PD was left to the operator's discretion. Patients were grouped according to whether PD was performed or not, and the one-year incidences of MACE and scaffold thrombosis were compared. A total of 768 patients were enrolled in the study; PD was performed in 526 (68.4%). There were no significant differences between the PD group and non-PD group in the majority of baseline characteristics, including the presence of moderate calcification and of B2/C lesions. Lesion length was similar (12.3±5.1 mm vs. 12.1±5.3 mm, p=0.6), as was RVD (2.6 mm for both groups, p=0.2). Residual in-scaffold stenosis (15.5±6.4% with PD, 15.0±6% without PD, p=0.3) and the need for bail-out scaffold/stent (4.2% with PD, 4.6% without PD, p=0.8) were comparable. Acute gain was higher in the non-PD group (1.14±0.3 mm vs. 1.21±0.4 mm, p=0.02). Clinical device success was 98.9% in both groups. At one year, there was no difference in MACE (5.4% in the PD group vs. 2.5% in the non-PD group, p=0.1). All individual components of TLR, death, and MI were similar as well as definite/probable scaffold thrombosis between the two groups. CONCLUSIONS: These results reflect very similar final angiographic and clinical results achieved with or without post-dilation in the treatment of low to moderately complex coronary lesions. Therefore, post-dilation should be performed whenever needed to optimise acute results.

Impact of intravascular ultrasound imaging on early and late clinical outcomes following percutaneous coronary intervention with drug-eluting stents.

OBJECTIVES: This study sought to assess the impact of intravascular ultrasound (IVUS)-guided versus angiography-guided drug-eluting stent (DES) implantation. BACKGROUND: There are limited data on IVUS guidance in the DES era. Therefore, we investigated the impact of IVUS guidance on clinical outcomes in the MATRIX (Comprehensive Assessment of Sirolimus-Eluting Stents in Complex Lesions) registry. METHODS: The MATRIX registry prospectively enrolled consecutive, unselected patients treated with sirolimus-eluting stents (SES) (n = 1,504); 631 patients (42%) underwent IVUS-guided stenting, and 873 (58%) had only angiographic guidance. We assessed 30-day, 1-year, and 2-year rates of death/myocardial infarction (MI), major adverse cardiac events (cardiac death, MI, or target vessel revascularization), and definite/probable stent thrombosis in 548 propensity-score matched patient pairs. RESULTS: After matching, baseline and angiographic characteristics were similar in IVUS and no-IVUS groups. Patients in the IVUS group had significantly less death/MI at 30 days (1.5% vs. 4.6%, p < 0.01), 1 year (3.3% vs. 6.5%, p < 0.01), and 2 years (5.0% vs. 8.8%, p < 0.01). Patients in the IVUS group had significantly less major adverse cardiac events at 30 days (2.2% vs. 4.8%, p = 0.04) and numerically less major adverse cardiac events at 1 year (9.1% vs. 13.5%, p = 0.07) and 2 years (12.9% vs. 16.7%, p = 0.18). Rates of MI were significantly lower in the IVUS group at 30 days (1.5% vs. 4.0%, p < 0.01), 1 year (1.8% vs. 4.8%, p < 0.01), and 2 years (2.1% vs. 5.7%, p < 0.01). CONCLUSIONS: IVUS-guided stent implantation appears to be associated with a reduction in both early and long-term clinical events. Further investigation in randomized controlled trials is warranted.

Assessing intermediate left main coronary lesions using intravascular ultrasound.

BACKGROUND: Angiographic assessment of a left main coronary artery stenosis (LMCS) is often difficult and unreliable. We aimed to evaluate the severity of ambiguous LMCSs by intravascular ultrasound (IVUS) and to clarify how frequently significant stenosis occurs in the "real world". METHODS: We retrospectively found 115 consecutive patients in our clinical IVUS database with a de novo, angiographically ambiguous, intermediate LMCS who underwent IVUS evaluation. Quantitative coronary angiography (QCA) and IVUS analyses were performed. We define a significant LMCS as a diameter stenosis >50% by QCA and a minimal lumen area <6.0 mm2 by IVUS. RESULTS: Ostial, mid, and distal LMCSs were seen in 44 (38.3%), 6 (5.2%), and 65 (56.5%) lesions. Overall, IVUS minimal lumen area and plaque burden measured 6.8 +/- 2.6 mm2 and 63% +/- 14%. A significant LMCS was seen in 51 (44.3%) lesions by IVUS but in only 15 (13.0%) lesions by QCA. In particular, only 36.4% of ostial lesions had a significant IVUS stenosis, and minimal lumen diameter by QCA was less well correlated with IVUS in ostial lesions than in other lesion locations. CONCLUSIONS: This real-world IVUS analysis showed that less than half of intermediate LMCSs had significant stenoses by IVUS assessment, especially for lesions located at the left main ostium. Such patients deserve IVUS assessment or physiologic assessment before blindly proceeding to revascularization.

[Relationship between plasma C-reactive protein level and neointimal hyperplasia volume in patients with zotarolimus-eluting stents. Volumetric analysis by three-dimensional intracoronary ultrasound]. / Asociación entre la concentración plasmática de proteína C reactiva y el volumen de hiperplasia neointimal en pacientes tratados con implante de stent liberador de zotarolimus. Análisis volumétrico con ecografía intracoronaria tridimensional.

INTRODUCTION AND OBJECTIVES: C-reactive protein (CRP) is an inflammatory marker that predicts cardiac events in patients with coronary syndromes. However, data on the relationship between the CRP level and in-stent restenosis are contradictory. The objective of this study was to investigate the relationship between the basal CRP level and the neointimal hyperplasia volume measured by intracoronary ultrasound 4 months after implantation of a zotarolimus-eluting stent. METHODS: The study included 40 consecutive patients who underwent zotarolimus-eluting stent implantation. Patients were divided into quartiles according to their preprocedural CRP level. Intracoronary ultrasound was performed after stent implantation and at 4 months, and the neointimal hyperplasia volume was determined using Simpson's rule. Correlation and linear regression analyses were used to evaluate the relationships between variables. Multivariate analysis was used to identify variables that were independently related to neointimal hyperplasia volume. RESULTS: The patients' mean age was 58 (8) years, 55% were male, and 40% had diabetes mellitus. There was no difference in baseline characteristics between the quartiles. The hyperplasia volumes were 4.8 (4.2) microl and 15.8 (10.0) microl in the first and fourth quartiles, respectively (P< .001). There was a significant positive correlation between the CRP level and neointimal hyperplasia volume (r = 0.64, P=.0001). The CRP level, the postimplantation lumen volume, and the final deployment pressure were all independent predictors of neointimal hyperplasia. CONCLUSIONS: In this study, an independent correlation was observed between the CRP level before zotarolimus-eluting stent implantation and the neointimal hyperplasia volume at 4-month follow-up.

Nonrandomized comparison of coronary stenting under intravascular ultrasound guidance of direct stenting without predilation versus conventional predilation with a semi-compliant balloon versus predilation with a new scoring balloon.

This study was conducted to determine the influence of lesion preparation using the AngioSculpt balloon on final stent expansion. Stent expansion remains an important predictor of restenosis and subacute thrombosis, even in the drug-eluting stent (DES) era. In these patients, the role of different predilation strategies has yet to be established. Two hundred ninety-nine consecutive de novo lesions treated with 1 >2.5-mm DES (Cypher or Taxus) under intravascular ultrasound guidance without postdilation, using 3 implantation strategies, were studied: (1) direct stenting without predilation (n = 145), (2) predilation with a conventional semi-compliant balloon (n = 117), and (3) predilation with the AngioSculpt balloon (n = 37). Stent expansion was defined as the ratio of intravascular ultrasound-measured minimum stent diameter and minimum stent area to the manufacturer's predicted stent diameter and area. These ratios were larger after AngioSculpt predilation, and a greater percentage of stents had final minimum stent areas >5.0 mm(2) (another commonly accepted criterion of adequate DES expansion). Lesion morphology, stent and lesion length, and reference vessel size did not affect DES expansion. In conclusion, in this observational, nonrandomized study, pretreatment with the AngioSculpt balloon enhanced stent expansion and minimized the difference between predicted and achieved stent dimensions.

Drug-eluting stents vs bare metal stents for the treatment of large coronary vessels.

BACKGROUND: Lately drug-eluting stents (DES) have dramatically reduced restenosis rates and need for repeat revascularization in a wide subset of lesion and patients. However, their benefit for the treatment of large vessels (> 3.0 mm) has yet to be established. OBJECTIVE: We investigated whether DES are superior to bare metal stents (BMS) in terms of clinical outcomes for the treatment of large coronary vessels. METHODS: This study assessed the long-term outcomes (cardiac death, acute myocardial infarction, and need for repeat intervention in the treated vessel) of patients treated with either a DES (Cypher and Taxus) or a BMS of > or = 3.5 mm in diameter. A total of 250 consecutive patients who underwent DES implantation were clinically followed for 1 year and compared to 250 patients who were treated with BMS. Interventions in the setting of acute ST elevation myocardial infarction and treatment of bypass grafts were excluded. RESULTS: Cypher was the DES deployed in 70.8% of cases. Most of the enrolled patients were men (78%) with single vessel disease (65.6%). The left anterior descending artery was the culprit vessel in 34.2% of cases. Bare metal stent and DES cohorts had equivalent interpolated reference vessel diameter (3.19 +/- 0.3 mm for BMS vs 3.18 +/- 0.2 for DES; P = .1). Lesion was significantly longer in the group treated with DES (13.4 +/- 5.1 mm for BMS group vs 14.3 +/- 3.5 for DES; P = .0018). After 1 year of clinical follow-up, 95.2% of patients treated with DES and 91.2% of the patients who received BMS were free of major events (P = .2). A trend toward higher target-lesion revascularization was noticed in the group treated with BMS (4.8% vs 1.6%; P = .07). CONCLUSION: Percutaneous treatment of large coronary vessels carries a low risk of clinical events irrespective of the type of stent used.

Late vascular response at the edges of sirolimus analogous-eluting stents in diabetic patients: An intravascular ultrasound study.

INTRODUCTION: Vascular response at edges of drug-eluting stents is still not well established, particularly in diabetic patients who are prone to aggressive atherosclerosis progression. Recently, Biolimus and Zotarolimus have demonstrated potent antiproliferative effects. OBJECTIVE: To compare the vascular responses at edges of sirolimus analogous-eluting stents in patients with and without diabetes, using intravascular ultrasound (IVUS). METHODS: 306 edges were analyzed in 153 patients treated with drug-eluting stents and divided in: diabetics (122 edges) and nondiabetics (166 edges). IVUS was performed postintervention and at 6-month follow-up and included 5 mm distal and proximal to the stented segment. Vessel, lumen, and plaque volumes were calculated. Volume variation (follow-up minus basal) was also calculated. Edge restenosis was defined as obstruction >50%. RESULTS: Baseline characteristics were similar between groups. In both groups the entire lesion length was covered (stent length/lesion length ratio was 1.5 for both groups). There were no differences in edge volumes and restenosis rate between the groups. Among diabetics, there was no significant volume variation. However, in nondiabetic patients there was significant increase in vessel volume in proximal (from 67.1 +/- 22 mm(3) to 72.2 +/- 25 mm(3): P = 0.02) and distal (from 54.4 +/- 22 mm(3) to 59.8 +/- 22 mm(3): P = 0.001) edges. CONCLUSION: Nondiabetic patients showed a significant positive vascular remodeling in proximal and distal edges of sirolimus analogous-eluting stent. This vascular mechanism was not observed in diabetic patients. Although different vascular responses were observed, restenosis rates were equivalent between the 2 groups at 6-month follow-up.

The accuracy of length measurements using different intravascular ultrasound motorized transducer pullback systems.

Accurate length measurements by intravascular ultrasound (IVUS) are necessary for stent length selection and for IVUS volumetric analysis. The comparative accuracy of commercially available transducer pullback systems--a necessity for accurate IVUS length and volume measurements--has never been studied. We evaluated the accuracy of four IVUS pullback systems by studying 180 patients (45 in each group) who had been treated with a single stent of known length. Stented lesions were located in the left anterior descending artery (n = 77), left circumflex artery (n = 41), right coronary artery (n = 41), left main (n = 2), and saphenous vein grafts (n = 19). The known lengths of implanted stents ranged from 8 to 33 mm. The correlations between known stent length and IVUS-measured stent length in each group were 0.92 for CVIS, 0.83 for BSC Galaxy, 0.63 for Endosonics TrackBack, and 0.69 for Volcano Model R-l00 research pullback device, respectively. Furthermore, the absolute value of the difference between the two measurements was 9.1 +/- 13.1%, 8.8 +/- 10.2%, 18.6 +/- 21.5%, and 17.5 +/- 31.4%, respectively. With the Volcano Model R-l00 research pullback device, there were 3 extreme outliers; if these three outliers were excluded, then the correlation improved from 0.69 to 0.91; and the absolute deviation from known stent length improved from 17.5 +/- 31.4% to 9.7 +/- 8.3%. Thus, there is a significant variation in length measurement accuracy among IVUS pullback devices. This should be taken into account both clinically and when planning scientific studies.

Intravascular ultrasound assessment of drug-eluting stent expansion.

BACKGROUND: In the drug-eluting stent (DES) era, stent expansion remains an important predictor of restenosis and subacute thrombosis. Compliance charts are developed to predict final minimum stent diameter (MSD) and area (MSA). The objectives of the study were (1) to assess DES expansion by comparing intravascular ultrasound (IVUS)-measured MSD and MSA against the values predicted by compliance charts and (2) to compare each DES against its bare-metal stent (BMS) equivalent. METHODS: We enrolled 200 patients with de novo coronary lesions treated with single, >2.5-mm Cypher (Cordis, Johnson & Johnson, Miami Lakes, FL) (sirolimus-eluting stent [SES], 133 patients) or Taxus (Boston Scientific, Natick, MA) (paclitaxel-eluting stent [PES], 67 patients) stent under IVUS guidance without another postdilation balloon. We used a comparison cohort of 65 equivalent BMS (Express 2 [Boston Scientific], 37 patients; Bx Velocity [Cordis, Johnson & Johnson], 28 patients) deployed under similar conditions. RESULTS: The DES achieved only 75% +/- 10% of predicted MSD and 66% +/- 17% of predicted MSA; this was similar for SES and PES. Furthermore, 24% of SES and 28% of PES did not achieve a final MSA of 5 mm(2), a consistent predictor of DES failure. The SES achieved 75% +/- 10% of predicted MSA versus 75% +/- 9% for Bx Velocity (P = .9). The PES achieved 79.9% +/- 14% of predicted MSA versus 79% +/- 10% for Express 2 (P = .8). Lesion morphology, arc and length of calcium, stent diameter and length, and implantation pressures did not affect expansion. CONCLUSIONS: Compliance charts fail to predict final MSD and MSA. A considerable percentage of DES does not achieve minimum standards of stent expansion. The SES and PES achieve similar expansion to their BMS platform, indicating that the polymer coating does not affect DES expansion in vivo. However, stent expansion cannot be predicted from preintervention IVUS lesion assessment.

Association of plaque characterization by intravascular ultrasound virtual histology and arterial remodeling.

Positive remodeling is more often observed in lesions of patients who have acute coronary syndromes or vulnerable (rupture-prone) plaques. However, there are few data that correlate plaque morphology, composition, and arterial remodeling in vivo. We evaluated coronary plaque characterization of lesions with positive remodeling using intravascular ultrasound (IVUS) radiofrequency data analysis. Seventy-seven nonbifurcation native coronary lesions (in 50 patients) were imaged in vivo using 30-MHz IVUS transducers. Lesions were classified into 4 plaque types, fibrous, fibrofatty, dense calcium, and necrotic core, by using processing of the radiofrequency signal validated in vitro. The remodeling index was calculated as the lesion external elastic membrane area divided by the proximal reference external elastic membrane area. Lesions were divided into 2 groups: positive remodeling (remodeling index>1.0, 26 lesions) and intermediate/negative remodeling (remodeling index

Intravascular ultrasonic assessment of stent diameters derived from manufacturer's compliance charts.

We used intravascular ultrasound (IVUS) to assess the accuracy of manufacturers' stent balloon compliance charts. Many interventional cardiologists rely on manufacturers' compliance charts to select stent size and optimize stent diameters according to inflation pressures during percutaneous procedures. We randomly selected 212 patients who had de novo coronary lesions that had been treated with a single, bare metal, > or =3.0-mm stent (Bx velocity, NIR, TETRA/PENTA, S660/S670/S7) under IVUS guidance. Cases of stent overlap and postdilatation with another balloon were excluded. Predicted stent diameters were derived from each manufacturer's compliance charts, and stent size and final maximal deployment pressures were derived from each physician's report. IVUS-measured minimum stent diameters (range 1.4 to 4.0 mm, mean 2.79 +/- 0.48) were smaller than predicted diameters (range 3.1 to 4.57 mm, mean 3.79 +/- 0.44). The ratio of IVUS to predicted diameters ranged from 44% to 97% (mean 74 +/- 10%). This finding was common to all 3 stent sizes: 74 +/- 12% for 3.0 mm, 73 +/- 9% for 3.5 mm, and 74 +/- 9% for 4.0-mm stents (p = 0.9). This finding was also common to all 4 stent manufacturers, 72 +/- 8% for Boston Scientific, 76 +/- 11% for Guidant, 73 +/- 9% for Cordis, and 74 +/- 11% for Medtronic (p = 0.13), and to different stent lengths. Only 3.8% of the stents achieved 90% of the predicted minimum stent diameters, and only 24.6% achieved 80% of the predicted minimum stent diameters. In conclusion, in human coronary arteries, minimal stent diameter measured by IVUS is significantly smaller than that predicted by in vitro compliance charts. These differences are independent of stent manufacturer, length, diameter, and deployment pressure.