Association between abdominal fat distribution and coronary plaque instability in patients with acute coronary syndrome.

BACKGROUND AND AIMS: This study aimed to assess possible association of detailed abdominal fat profiles with coronary plaque characteristics in patients with acute coronary syndrome (ACS). METHODS AND RESULTS: In 60 patients with ACS, culprit arteries were evaluated at 1-mm intervals (length analyzed: 66 ± 28 mm) by grayscale and integrated backscatter intravascular ultrasound (IB-IVUS) before percutaneous coronary intervention. Standard IVUS indexes (as a volume index: volume/length), plaque components (as percent tissue volume) and fibrous cap thickness (FCT) were assessed by IB-IVUS. Plain abdominal computed tomography was performed to evaluate subcutaneous adipose tissue (SAT) area, visceral adipose tissue (VAT) area, and VAT/SAT ratio. While SAT area only correlated with vessel volume (r = 0.27, p = 0.04), VAT area correlated positively with vessel (r = 0.30, p = 0.02) and plaque (r = 0.33, p = 0.01) volumes and negatively with FCT (r = -0.26, p = 0.049), but not with percent plaque volume and plaque tissue components. In contrast, higher VAT/SAT ratio significantly correlated with higher percent lipid (r = 0.34, p = 0.008) and lower percent fibrous (r = -0.34, p = 0.007) volumes with a trend toward larger percent plaque volume (r = 0.19, p = 0.15), as well as thinner FCT (r = -0.53, p < 0.0001). In the multiple regression analysis, higher VAT/SAT ratio was independently associated with higher percent lipid with lower percent fibrous volumes (p = 0.03 for both) and thinner fibrous cap thickness (p = 0.0001). CONCLUSION: Coronary plaque vulnerability, defined as increased lipid content with thinner fibrous cap thickness, appears to be more related to abnormal abdominal fat distribution, or so-called hidden obesity, compared with visceral or subcutaneous fat amount alone in patients with ACS.

Comparison between instantaneous wave-free ratio versus morphometric assessments by intracoronary imaging.

Anatomical measurements obtained by intracoronary imaging devices are reported to correlate significantly with fractional flow reserve (FFR). Instantaneous wave-free ratio (iFR) is a nonhyperemic index of stenosis severity with discordant reports regarding its accuracy in relation to FFR. There is no information on the correlation of iFR with measurements derived from intracoronary imaging devices. The purpose of this study was to assess the relationship among iFR, intravascular ultrasound (IVUS), and optical frequency domain imaging (OFDI) parameters. Eighty lesions in 72 patients who underwent elective angiography and had intermediate lesions were enrolled. All lesions were assessed by iFR, FFR, IVUS, and OFDI. iFR was ≤ 0.89 in 21 (26%) lesions and FFR was ≤ 0.80 in 41 (51%) lesions. iFR correlated significantly with both IVUS-derived minimum lumen area (MLA) (r = 0.375, p = 0.003) and OFDI-derived MLA (r = 0.357, p = 0.005). FFR also correlated significantly with both IVUS-derived MLA (r = 0.472, p < 0.001) and OFDI-derived MLA (r = 0.445, p < 0.001). Among the lesions with FFR ≤ 0.80, iFR > 0.89 (mismatch) was observed in 20 lesions. There was no lesion with iFR ≤ 0.89 (reverse mismatch) among the lesions with FFR > 0.80. The lesion location among three major coronary vessels was related with the discrepancy between iFR and FFR (p = 0.007). In conclusion, iFR and FFR showed a significant correlation with IVUS and OFDI measurements. The discrepancy of iFR and FFR was associated with the lesion locations.

Assessment of bioresorbable scaffold with a novel high-definition 60 MHz IVUS imaging system: Comparison with 40-MHz IVUS referenced to optical coherence tomography.

BACKGROUND: In vivo assessment of bioresorbable scaffold (BRS) is of growing clinical interest. The novel 60MHz high-definition intravascular ultrasound (HD-IVUS) has been developed to overcome the limitations of conventional 40 MHz IVUS. This study aimed to evaluate the performance and limitations of 60 MHz HD-IVUS compared with 40 MHz IVUS with respect to polymeric-strut visualization, quantitative and qualitative analysis, and feasibility of high-speed pullback in the assessment of BRS. METHODS AND RESULTS: In a bench-test model, 361 struts were analyzed to evaluate the influence of ultrasound-beam angles and proximity of adjacent struts on IVUS visualization of BRS struts. Various settings were created by deforming the BRS and positioning the transducer offcenter. In an in vivo swine coronary model, scaffold and lumen areas, degree of visible external elastic membrane, incomplete strut apposition, and strut fracture were evaluated in 59 matched cross-sections obtained at conventional (0.5 mm/sec) and high speed (10 mm/sec) pullbacks. Both studies utilized optical coherence tomography (OCT) as reference. Overall, 60 MHz HD-IVUS demonstrated significantly improved visualization of polymeric struts compared with 40 MHz IVUS (well-visualized: 84.5% vs 62.3%, not visible: 4.4% vs 13.9%, respectively. P < 0.001), which was less affected by the beam angle and adjacent strut proximity. In the in vivo model, 60-MHz HD-IVUS showed better agreement of area measurements and strut abnormalities with OCT than 40 MHz IVUS. These findings were also confirmed on high-speed pullback images of 60 MHz HD-IVUS. CONCLUSION: As referenced to OCT, this study showed superiority of 60 MHz HD-IVUS over 40 MHz IVUS in the assessment of BRS with feasibility of high-speed pullback imaging.

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.

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.

Evaluation of a fully bioresorbable vascular scaffold in patients with coronary artery disease: design of and rationale for the ABSORB III randomized trial.

BACKGROUND: Randomized trials have demonstrated progressive improvements in clinical and angiographic measures of restenosis with technologic iterations from balloon angioplasty to bare-metal stents and subsequently to drug-eluting stents (DES). However, the permanent presence of a metal stent prevents coronary vasomotion, autoregulation, and adaptive coronary remodeling. The limitations imposed by a permanent metal implant may be overcome with a bioresorbable scaffold. ABSORB III is a large-scale, multicenter, randomized trial designed to support US premarket approval of the ABSORB BVS platform and is the first study with sufficient size to allow valid examination of the relative clinical outcomes between metallic DES and bioresorbable scaffold. DESIGN: ABSORB III (ClincalTrials.gov NCT01751906) will register approximately 2,262 patients and includes a lead-in phase (n = 50), the primary randomized analysis group (n = 2,000), an imaging cohort (n = 200), and a pharmacokinetic substudy (n = 12). In the primary analysis group, approximately 2,000 patients with up to 2 de novo native coronary artery lesions in separate epicardial vessels will be prospectively assigned in a 2:1 ratio to ABSORB BVS versus XIENCE everolimus-eluting stents (EES). The primary end point is target lesion failure (the composite of cardiac death, target vessel-related myocardial infarction, or ischemia-driven target lesion revascularization) at 1 year, powered for noninferiority of ABSORB BVS compared to XIENCE EES. Clinical follow-up will continue for 5 years. Enrollment has been completed, and the principal results will be available in the fall of 2015. CONCLUSIONS: The large-scale ABSORB III randomized trial will evaluate the safety and effectiveness of ABSORB BVS compared to XIENCE EES in the treatment of patients with coronary artery disease.

Association between blood glucose variability and coronary plaque instability in patients with acute coronary syndromes.

BACKGROUND: Blood glucose variability is receiving considerable attention as a new risk factor for coronary artery disease. This study aimed to investigate the association between blood glucose variability and coronary plaque tissue characteristics. METHODS: In 57 patients with acute coronary syndrome, integrated backscatter intravascular ultrasound (IB-IVUS) and gray-scale IVUS were performed before balloon dilatation or stent implantation in the culprit vessels. Standard IVUS indices were evaluated for volume index (volume/length), and plaque components were measured by IB-IVUS for percent tissue volume. In addition to conventional glucose indicators, blood glucose variability in a stable state was determined by calculating the mean amplitude of glycemic excursions (MAGE) using a continuous glucose monitoring system. RESULTS: Higher MAGE values were significantly correlated with larger percent plaque volumes (r = 0.32, p = 0.015), and increased lipid (r = 0.44, p = 0.0006) and decreased fibrous (r = -0.45, p = 0.0005) plaque components. In contrast, HbA1c or fasting plasma glucose values were not significantly correlated with plaque volumes and percent plaque components. Homeostasis model assessment of insulin resistance values were positively correlated with vessel (r = 0.35, p = 0.007) and plaque (r = 0.27, p = 0.046) volumes, but not with percent plaque components. In multiple regression analysis, higher MAGE values were independently associated with increased lipid (ß = 0.80, p = 0.0035) and decreased fibrous (ß = -0.79, p = 0.0034) contents in coronary plaques. CONCLUSIONS: Among all glucose indicators studied, only higher blood glucose variability was an independent determinant of increased lipid and decreased fibrous contents with larger plaque burden, suggesting blood glucose variability as one of the important factors related to coronary plaque vulnerability.

Baseline and 9 months IVUS analysis of the bifurcation-dedicated biolimus A9-eluting Axxess stent system: the DIVERGE IVUS substudy.

BACKGROUND: Percutaneous treatment of complex coronary bifurcation lesions remains challenging, even in the drug-eluting stent era. We sought to evaluate the baseline and 9 months intravascular ultrasound (IVUS) analysis of the Axxess™ stent, a self-expanding, Biolimus A9™-eluting, and dedicated bifurcation stent. METHODS AND RESULTS: We enrolled the first 76 patients from selected sites of the 302 patients large DIVERGE trial (a prospective, single-arm, multicenter trial evaluating the safety and efficacy of the Axxess stent). Both baseline and 9 months IVUS images were collected for serial two-dimensional (2D) and 3D analysis. A minimal amount and a low percentage of neointimal volume index were seen in the Axxess stent at 9 months (0.4 ± 0.6 mm(3) /mm and 4.3 ± 5.2%, respectively). Vessel, lumen, and stent volume indices increased significantly (respectively, 17.0 ± 3.6 to 18.9 ± 3.7 mm(3) /mm, P < 0.0001; 7.3 ± 2.0 to 9.2 ± 2.5 mm(3) /mm, P < 0.0001; and 7.4 ± 2.0 to 9.6 ± 2.6 mm(3) /mm, P < 0.0001). This resulted in minimum lumen area (MLA) enlargement (6.1 ± 1.9 to 7.2 ± 2.3 mm(2) , P < 0.0001), whereas peristent plaque area decreased (8.7 ± 2.5 to 8.5 ± 2.1 mm(3) /mm, P = 0.016). At 9 months, 16 (26%) incomplete stent apposition (ISA) persisted from baseline, while six resolved (9.7%). Only one (2%) ISA was late acquired. In the additional distal sirolimus-eluting stents, MLA decreased from 4.3 ± 1.1 to 4.1 ± 1.2 mm(2) (P = 0.04) at 9 months for the main branch, and from 3.4 ± 1.2 to 3.2 ± 1.2 mm(2) (P = 0.09) for the side branch. CONCLUSIONS: The dedicated bifurcation Axxess stent system demonstrates significant stent volume increase with minimal neointimal formation and a low incidence of late-acquired ISA at 9 months.

Intravascular ultrasound analysis of small vessel lesions treated with the Sparrow coronary stent system: results of the CARE II trial.

OBJECTIVES: The aim of this study was to evaluate the Sparrow sirolimus-eluting stent (Sparrow-SES) against the Sparrow bare-metal stent (Sparrow-BMS) and conventional balloon-expandable bare-metal stent (BMS: Driver/Micro-Driver stent, Medtronic Vascular, Santa Rosa, CA). BACKGROUND: The Sparrow stent (Biosensors International, Singapore) consists of a guide wire-based, self-expandable, ultra-thin nitinol stent. The performance of this device with sirolimus in a fully biodegradable polymer has not been determined. METHODS: A total of 74 patients were included in this intravascular ultrasound (IVUS) sub-study of the CARE II trial, which was a prospective, randomized, multicenter trial in the treatment of single de novo native coronary artery lesions in vessels ranging from 2.0 mm to 2.75 mm in diameter (Sparrow-SES: n = 31, Sparrow-BMS: n = 22, BMS: n = 21). RESULTS: Stent volume index (VI) was significantly increased 8-month later in Sparrow-SES and Sparrow-BMS, but not in BMS (4.0 ± 1.0 to 4.6 ± 1.0 mm(3) /mm, p<0.0001, 4.0 ± 0.6 to 4.4 ± 0.8 mm(3) /mm, p<0.05, and 5.2 ± 1.0 to 5.1 ± 0.9 mm(3) /mm, p=0.421, respectively). % neointimal obstruction in Sparrow-SES was significantly smaller than those in Sparrow-BMS and BMS at follow-up (17.6 ± 9.4 vs. 36.2 ± 13.8 and 39.9 ± 11.1%, p<0.001). Sparrow-SES showed a mean 15% stent expansion and good suppression of neointimal proliferation, resulting in a significantly lower percentage of change in lumen VI during follow-up period (Sparrow-SES: -6.2 ± 16.2%, Sparrow-BMS: -30.4 ± 11.6%, BMS: -40.4 ± 10.0%, p<0.001). CONCLUSIONS: The self-expanding Sparrow-SES demonstrated chronic stent expansion, good suppression of neointimal proliferation and resulted in a more preserved lumen in stented small vessels compared with the Sparrow-BMS and conventional balloon expandable BMS.

Contemporary Infrapopliteal Intervention for Limb Salvage and Wound Healing.

Infrapopliteal arterial disease is a significant cause of critical limb ischemia (CLI), whether single-segment or multisegment disease. The collaboration between the tremendous advancements in endovascular technology and the refinement of endovascular techniques has renewed the classic infrapopliteal interventions during the past decade. With this paradigm shift in the treatment of CLI, the role of a comprehensive approach of different disciplines for tissue loss is becoming greater. Given the increasing global burden of CLI, we review the cutting-edge diagnostic and endovascular approaches to infrapopliteal artery disease, and the importance of wound management in optimizing clinical outcomes.

Contemporary infrapopliteal intervention for limb salvage and wound healing: harmonization of revascularization and wound management.

Infrapopliteal arterial disease is a significant cause of critical limb ischemia (CLI), whether single-segment or multisegment disease. The collaboration between the tremendous advancements in endovascular technology and the refinement of endovascular techniques has renewed the classic infrapopliteal interventions during the past decade. With this paradigm shift in the treatment of CLI, the role of a comprehensive approach of different disciplines for tissue loss is becoming greater. Given the increasing global burden of CLI, we review the cutting-edge diagnostic and endovascular approaches to infrapopliteal artery disease, and the importance of wound management in optimizing clinical outcomes.

Duplex criteria for in-stent restenosis in the superficial femoral artery.

OBJECTIVES: To elucidate the optimal cutoff and accuracy of duplex ultrasonography (DUS) parameters for in-stent restenosis (ISR) after nitinol stenting in the superficial femoral artery (SFA). BACKGROUND: Few data are available regarding the performance of DUS for binary ISR based on quantitative vessel analysis (QVA) in the era of SFA nitinol stenting. METHODS: This retrospective study included 74 in-stent stenoses of SFA who underwent DUS before follow-up angiography. DUS parameters, such as peak systolic velocity (PSV) and the peak systolic velocity ratio (PSVR), were compared with percent diameter stenosis (%DS) from a QVA basis. RESULTS: There was a statistically significant correlation (P < 0.001) between "%DS and PSV" and "%DS and PSVR," and the correlation with %DS proved to be stronger in PSVR (R = 0.720) than in PSV (R = 0.672). The best performing parameter for ISR (50% or greater stenosis) was revealed PSVR, as the areas under the receiver operator characteristics curves using PSVR and PSV were 0.908 and 0.832, respectively. A PSVR cut off value of 2.85 yielded the best predictive value with sensitivity of 88%, specificity of 84%, and accuracy of 86%. The positive predictive value was 85% and the negative predictive value was 88%. CONCLUSIONS: A PSVR of 2.85 is the optimal threshold for ISR after nitinol stenting in the SFA. Further large prospective studies are required for the validation and establishment of uniform criteria for DUS parameters.

Variability in quantitative and qualitative analysis of intravascular ultrasound and frequency domain optical coherence tomography.

BACKGROUND: Frequency-domain optical coherence tomography (FD-OCT) is an intravascular imaging technique now available in the United States. However, the importance of level of training required for analysis using intravascular ultrasound (IVUS) and FD-OCT is unclear. The aim of this study was to evaluate inter- and intra-observer variability between expert and beginner analysts interpreting IVUS and FD-OCT images. METHODS AND RESULTS: Two independent expert analysts and two independent beginner analysts evaluated a total of 226 ± 2 stent cross-sections with IVUS and 232 ± 2 stent cross-sections with FD-OCT in 14 patients after stenting. Inter- and intra-observer variability for determining stent volume index (VI), as well as identifying incomplete stent apposition and dissection were assessed. The inter- and intra-observer variability of stent VI was minimal for both beginner and expert analysts regardless of imaging technology (random variability: 0.38 vs. 0.05 mm(3) /mm for IVUS, 0.26 vs. 0.08 mm(3) /mm for FD-OCT). Although qualitative IVUS analysis at the patient level revealed no significant difference between beginners and experts, this was not the case for FD-OCT. The number of overall qualitative findings noted by beginner and expert analysts were more variable (overestimated or underestimated) with FD-OCT. CONCLUSION: Despite varying levels of training, the increased resolution of FD-OCT compared to IVUS provides better detection and less variability in quantitative image analysis. On the contrary, this increased resolution not only increases the rate but also the variability of detection of qualitative image analysis, especially for beginner analysts.

Improved automated lumen contour detection by novel multifrequency processing algorithm with current intravascular ultrasound system.

OBJECTIVES: The aim of this study was to evaluate a new fully automated lumen border tracing system based on a novel multifrequency processing algorithm. BACKGROUND: We developed the multifrequency processing method to enhance arterial lumen detection by exploiting the differential scattering characteristics of blood and arterial tissue. The implementation of the method can be integrated into current intravascular ultrasound (IVUS) hardware. METHODS: This study was performed in vivo with conventional 40-MHz IVUS catheters (Atlantis SR Pro™, Boston Scientific Corp, Natick, MA) in 43 clinical patients with coronary artery disease. A total of 522 frames were randomly selected, and lumen areas were measured after automatically tracing lumen borders with the new tracing system and a commercially available tracing system (TraceAssist™) referred to as the "conventional tracing system." The data assessed by the two automated systems were compared with the results of manual tracings by experienced IVUS analysts. RESULTS: New automated lumen measurements showed better agreement with manual lumen area tracings compared with those of the conventional tracing system (correlation coefficient: 0.819 vs. 0.509). When compared against manual tracings, the new algorithm also demonstrated improved systematic error (mean difference: 0.13 vs. -1.02 mm(2) ) and random variability (standard deviation of difference: 2.21 vs. 4.02 mm(2) ) compared with the conventional tracing system. CONCLUSIONS: This preliminary study showed that the novel fully automated tracing system based on the multifrequency processing algorithm can provide more accurate lumen border detection than current automated tracing systems and thus, offer a more reliable quantitative evaluation of lumen geometry.

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 myocardial bridging on coronary artery plaque formation and long-term mortality after heart transplantation.

OBJECTIVES: This study aimed to explore the impact of myocardial bridging (MB) on early development of cardiac allograft vasculopathy and long-term graft survival after heart transplantation. BACKGROUND: MB has been reported to be associated with acceleration of proximal plaque development and endothelial dysfunction in native coronary atherosclerosis. However, its clinical significance in heart transplantation remains unclear. METHODS: In 103 heart-transplant recipients, serial (baseline and 1-year post-transplant) volumetric intravascular ultrasound (IVUS) analyses were performed in the first 50 mm of the left anterior descending (LAD) artery. Standard IVUS indices were evaluated in 3 equally divided LAD segments (proximal, middle, and distal segments). MB was defined by IVUS as an echolucent muscular band lying on top of the artery. The primary endpoint was death or re-transplantation, assessed for up to 12.2 years (median follow-up: 4.7 years). RESULTS: IVUS identified MB in 62% of the study population. At baseline, MB patients had smaller intimal volume in the distal LAD than non-MB patients (p = 0.002). During the first year, vessel volume decreased diffusely irrespective of the presence of MB. Intimal growth diffusely distributed in non-MB patients, whereas MB patients demonstrated significantly augmented intimal formation in the proximal LAD. Kaplan-Meier analysis revealed significantly lower event-free survival in patients with versus without MB (log-rank p = 0.02). In multivariate analysis, the presence of MB was independently associated with late adverse events [hazard ratio 5.1 (1.6-22.2)]. CONCLUSION: MB appears to relate to accelerated proximal intimal growth and reduced long-term survival in heart-transplant recipients.

Predictors of adverse clinical outcomes after successful infrapopliteal intervention.

OBJECTIVES: To clarify the clinical and angiographical variables related to delayed wound healing, major amputation and death after successful infrapopliteal intervention in critical limb ischemia patients with tissue loss. BACKGROUND: There is an underappreciation of adverse clinical outcomes after successful infrapopliteal intervention. METHODS: Stent-assisted infrapopliteal angioplasty was successful in 106 limbs in 85 patients. Successful intervention was defined as revascularization of at least one straight-line flow to the foot. RESULTS: At 6 months and 1, 2, and 5 years, the repeat intervention-free rates were 55.0, 49.6, 44.4, and 36.1%, respectively; the amputation-free survival rates were 85.7, 68.0, 54.5, and 39.8%, respectively; and the limb salvage rates were 96.0, 92.4, 86.3, and 86.3%, respectively. An infectious wound was an independent predictor of major amputation after successful intervention. The complete wound healing rates were 36.8, 57.5, 67.9, and 73.6% at 3, 6, 9, and 12 months, respectively. In stepwise multivariate Cox analysis, diabetes mellitus, an infectious wound, and the pedal arch classification were identified as independent predictors of wound healing. The long-term survival rates at 6 months and 1, 2, and 5 years were 89.5, 73.8, 62.0, and 43.4%, respectively. Stepwise multivariate Cox analysis indentified end-stage renal disease (ESRD) on hemodialysis to be an independent predictor of death. CONCLUSIONS: An infectious wound, comorbidities of diabetes mellitus and ESRD on hemodialysis and classification of pedal arch can be predictors of adverse clinical outcomes after successful infrapopliteal intervention.

Effect of rosiglitazone on progression of coronary atherosclerosis in patients with type 2 diabetes mellitus and coronary artery disease: the assessment on the prevention of progression by rosiglitazone on atherosclerosis in diabetes patients with cardiovascular history trial.

BACKGROUND: Rosiglitazone has several properties that may affect progression of atherosclerosis. The Assessment on the Prevention of Progression by Rosiglitazone on Atherosclerosis in Diabetes Patients With Cardiovascular History (APPROACH) study was undertaken to determine the effect of the thiazolidinedione rosiglitazone on coronary atherosclerosis as assessed by intravascular ultrasound compared with the sulfonylurea glipizide. METHODS AND RESULTS: This was a randomized, double-blind, controlled 18-month study in 672 patients aged 30 to 80 years with established type 2 diabetes mellitus treated by lifestyle, 1 oral agent, or submaximal doses of 2 oral agents who had at least 1 atherosclerotic plaque with 10% to 50% luminal narrowing in a coronary artery that had not undergone intervention during a clinically indicated coronary angiography or percutaneous coronary intervention. The primary outcome was change in percent atheroma volume in the longest and least angulated epicardial coronary artery that had not undergone intervention. Secondary outcomes included change in normalized total atheroma volume and change in total atheroma volume in the most diseased baseline 10-mm segment. Rosiglitazone did not significantly reduce the primary outcome of percent atheroma volume compared with glipizide (-0.64%; 95% confidence interval, -1.46 to 0.17; P=0.12). The secondary outcome of normalized total atheroma volume was significantly reduced by rosiglitazone compared with glipizide (-5.1 mm(3); 95% confidence interval, -10.0 to -0.3; P=0.04); however, no significant difference between groups was observed for the change in total atheroma volume within the most diseased baseline 10-mm segment (-1.7 mm(3); 95% confidence interval, -3.9 to 0.5; P=0.13). CONCLUSIONS: Rosiglitazone did not significantly decrease the primary end point of progression of coronary atherosclerosis more than glipizide in patients with type 2 diabetes mellitus and coronary atherosclerosis. Clinical Trial Registration- http://www.clinicaltrials.gov. Unique Identifier: NCT00116831.

Assessment of macro- and microcirculation in contemporary critical limb ischemia.

OBJECTIVES: A paucity of data exists regarding manifestations of macro- and microcirculation in contemporary critical limb ischemia (CLI). The aim of this study was (1) to evaluate the differences in foot circulation based on angiographic findings, (2) to clarify the relationship between macro- and microcirculation, and (3) to investigate the effects of postural changes on micro as well as macrocirculation between the supine position to the dependent position. METHODS: A total of 40 critically ischemic limbs in 29 patients were included in this study. Noninvasive evaluation of macrocirculation, based on the ankle brachial index (ABI) and ankle pressure, and microcirculation, using skin perfusion pressure (SPP), was performed in both the supine and dependent positions. RESULTS: There was no significant difference in macro- and microcirculations between any angiographical involvements. In the supine position, dorsal SPP correlated significantly with ABI (P = 0.021, r = 0.363) and ankle-pressure (P = 0.001, r = 0.495), whereas plantar SPP failed to correlate with ABI (P = 0.198, r = 0.208) or ankle-pressure (P = 0.185, r = 0.214). In the dependent position, however, SPP showed no significant correlation with ABI and ankle pressure. Postural change from the supine to dependent position yielded a significant increase in SPP (dorsal: 37.2 ± 16.2 to 77.9 ± 17.7 mm Hg, P < 0.001; plantar: 33.6 ± 17.3 to 75.7 ± 18.3 mm Hg, P < 0.001) as well as ABI and ankle-pressure (ABI: 0.70 ± 0.35 to 0.78 ± 0.42, P = 0.003; ankle-pressure; 108 ± 61 to 111 ± 60 mm Hg, P = 0.038). The effect of postural change on SPP showed no difference between patients with and without any clinical and angiographical complications. CONCLUSIONS: Of microcirculation assessed, only dorsal SPP correlated significantly with macrocirculation in the supine position. Furthermore, postural change from the supine to dependent position produced a dramatic improvement in microcirculation due to the effects of gravity.

Discrepancy in the assessment of jailed side branch lesions by visual estimation and quantitative coronary angiographic analysis: comparison with fractional flow reserve.

OBJECTIVE: We sought to evaluate the variability in the assessment of jailed side branch (SB) lesions by visual estimation and quantitative coronary angiography (QCA) and to compare those results with fractional flow reserve (FFR). METHODS: Twenty jailed SB lesions with available FFR (median 0.76; range, 0.39-0.94) were selected from the PRESSURE trial. Lesions were assessed by three independent QCA core laboratories with different QCA systems and by three different cardiologist groups (five European bifurcation club members, five Korean experts, and five trainees). Agreements of the continuous measurements were expressed as the intraclass correlation coefficient (ICC) and average coefficient of variance (CV), and those of the categorical values as kappa. RESULTS: Mean minimum lumen diameter (MLD) and % diameter stenosis differed among the three QCA systems up to 0.30 mm and 9.65%, respectively (P < 0.001). Three QCA systems showed fair agreement for the measurements of reference diameter, % diameter stenosis, MLD, and lesion length (ICC 0.346-0.686, CV 8.7-29.5%), and a poor agreement on stenosis of 75% or more (Fleiss κ 0.14 and mean κ 0.18). Agreements of visual estimation among the three groups were poor to fair (Fleiss κ 0.167-0.367). Sensitivity and specificity for predicting ischemia-inducible lesion (FFR < 0.75) were 64.7% and 48.0% for visual estimation and 56.6% and 56.6% by QCA, respectively. Visual estimation overestimated the % diameter stenosis and functional significance of the lesions compared with QCA (P < 0.001) and FFR (P = 0.036). CONCLUSIONS: Angiographic assessment of jailed SB lesions by both QCA and visual estimation showed variability. Visual estimation tended to overestimate the severity of jailed SB lesions compared to FFR and QCA.