Volumetric Intravascular Ultrasound Analysis Research Articles

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

ObjectivesThis 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. BackgroundMB 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. MethodsIn 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). ResultsIVUS 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)]. ConclusionMB appears to relate to accelerated proximal intimal growth and reduced long-term survival in heart-transplant recipients.

End-diastolic segmentation of intravascular ultrasound images enables more reproducible volumetric analysis of atheroma burden.

Volumetric intravascular ultrasound (IVUS) analysis is currently performed at a fixed frame interval, neglecting the cyclic changes in vessel dimensions occurring during the cardiac cycle that can affect the reproducibility of the results. Analysis of end-diastolic (ED) IVUS frames has been proposed to overcome this limitation. However, at present, there is lack of data to support its superiority over conventional IVUS. The present study aims to compare the reproducibility of IVUS volumetric analysis performed at a fixed frame interval and at the ED frames, identified retrospectively using a novel deep-learning methodology. IVUS data acquired from 97 vessels were included in the present study; each vessel was segmented at 1 mm interval (conventional approach) and at ED frame twice by an expert analyst. Reproducibility was tested for the following metrics; normalized lumen, vessel and total atheroma volume (TAV), and percent atheroma volume (PAV). The mean length of the analyzed segments was 50.0 ± 24.1 mm. ED analysis was more reproducible than the conventional analysis for the normalized lumen (mean difference: 0.76 ± 4.03 mm3 vs. 1.72 ± 11.37 mm3 ; p for the variance of differences ratio < 0.001), vessel (0.30 ± 1.79 mm3 vs. -0.47 ± 10.26 mm3 ; p < 0.001), TAV (-0.46 ± 4.03 mm3 vs. -2.19 ± 14.39 mm3 ; p < 0.001) and PAV (-0.12 ± 0.59% vs. -0.34 ± 1.34%; p < 0.001). Results were similar when the analysis focused on the 10 mm most diseased segment. The superiority of the ED approach was due to a more reproducible detection of the segment of interest and to the fact that it was not susceptible to the longitudinal motion of the IVUS probe and the cyclic changes in vessel dimensions during the cardiac cycle. ED IVUS segmentation enables more reproducible volumetric analysis and quantification of TAV and PAV that are established end points in longitudinal studies assessing the efficacy of novel pharmacotherapies. Therefore, it should be preferred over conventional IVUS analysis as its higher reproducibility is expected to have an impact on the sample size calculation for the primary end point.

A deep learning methodology for the automated detection of end-diastolic frames in intravascular ultrasound images

Coronary luminal dimensions change during the cardiac cycle. However, contemporary volumetric intravascular ultrasound (IVUS) analysis is performed in non-gated images as existing methods to acquire gated or to retrospectively gate IVUS images have failed to dominate in research. We developed a novel deep learning (DL)-methodology for end-diastolic frame detection in IVUS and compared its efficacy against expert analysts and a previously established methodology using electrocardiographic (ECG)-estimations as reference standard. Near-infrared spectroscopy-IVUS (NIRS-IVUS) data were prospectively acquired from 20 coronary arteries and co-registered with the concurrent ECG-signal to identify end-diastolic frames. A DL-methodology which takes advantage of changes in intensity of corresponding pixels in consecutive NIRS-IVUS frames and consists of a network model designed in a bidirectional gated-recurrent-unit (Bi-GRU) structure was trained to detect end-diastolic frames. The efficacy of the DL-methodology in identifying end-diastolic frames was compared with two expert analysts and a conventional image-based (CIB)-methodology that relies on detecting vessel movement to estimate phases of the cardiac cycle. A window of ± 100 ms from the ECG estimations was used to define accurate end-diastolic frames detection. The ECG-signal identified 3,167 end-diastolic frames. The mean difference between DL and ECG estimations was 3 ± 112 ms while the mean differences between the 1st-analyst and ECG, 2nd-analyst and ECG and CIB-methodology and ECG were 86 ± 192 ms, 78 ± 183 ms and 59 ± 207 ms, respectively. The DL-methodology was able to accurately detect 80.4%, while the two analysts and the CIB-methodology detected 39.0%, 43.4% and 42.8% of end-diastolic frames, respectively (P < 0.05). The DL-methodology can identify NIRS-IVUS end-diastolic frames accurately and should be preferred over expert analysts and CIB-methodologies, which have limited efficacy.

Preliminary Pilot Study of Combined Effects of Physical Activity and Achievement of LDL-Cholesterol Target on Coronary Plaque Volume Changes in Patients with Acute Coronary Syndrome.

Background: We investigated the combined effects of physical activity (PA) and aggressive low-density lipoprotein cholesterol (LDL-C) reduction on the changes in coronary plaque volume (PV) in patients with acute coronary syndrome (ACS) using volumetric intravascular ultrasound (IVUS) analysis. Methods: We retrospectively analyzed data from two different prospective clinical trials that involved 101 ACS patients who underwent percutaneous coronary intervention (PCI) and assessed the non-culprit sites of PCI lesions using IVUS at baseline and at the follow-up. After PCI, all the patients participated in early phase II comprehensive cardiac rehabilitation. Patients were divided into four groups based on whether the average daily step count, measured using a pedometer, was 7000 steps of more and whether the follow-up LDL-C level was <70 mg/dL. At the time of follow-up, we examined the correlation of changes in the PV with LDL-C and PA. Results: The baseline characteristics of the four study groups were comparable. At the follow-up, plaque regression in both the achievement group (PA and LDL-C reduction) was higher than that in the other three groups. In addition, plaque reduction independently correlated with increased PA and reduction in LDL-C level. Conclusions: Combined therapy of intensive PA and achievement of LDL-C target retarded coronary PV in patients with ACS.

Intravascular ultrasound of the proximal left anterior descending artery is sufficient to detect early cardiac allograft vasculopathy.

Cardiac allograft vasculopathy (CAV) can be detected early with intravascular ultrasound (IVUS), but there is limited information on the most efficient imaging protocol. Coronary angiography and IVUS of the three coronary arteries were performed. Volumetric IVUS analysis was performed, and a Stanford grade determined for each vessel. Eighteen patients were included 18 (range 12-24) months after transplantation. Angiographic CAV severity ranged from none (CAV0) to mild (CAV1), whereas IVUS CAV severity ranged from none (Stanford grade I) to severe (grade IV). Maximal intimal thickness measured with IVUS was significantly greater in the LAD (0.84±0.48mm) than in the LCX (0.46±0.32mm) or the RCA (0.53±0.41mm, P=.005). Diagnostic accuracy of IVUS in the left anterior descending artery was 100% (18 of 18 Stanford grades matched the patient's highest overall Stanford grade), 66% in the right coronary artery (12 of 18), and 56% in the left circumflex artery (11 of 18). The minimal required length of left anterior descending artery pullbacks to attain 100% accuracy was 36mm (range 3-36mm) distal from the guide catheter ostium. These data suggest that focal IVUS imaging of the proximal LAD followed by volumetric analysis may suffice when screening for transplant vasculopathy.

Prospective randomized comparison of clinical and angiographic outcomes between everolimus-eluting vs. zotarolimus-eluting stents for treatment of coronary restenosis in drug-eluting stents: intravascular ultrasound volumetric analysis (RESTENT-ISR trial).

At present no proven standard treatment for drug-eluting stent (DES) restenosis is available, and the efficacy and safety of everolimus-eluting stent (EES) and zotarolimus-eluting stent (ZES) for DES restenosis are limited. The purpose of this prospective, randomized 9-month intracoronary ultrasound (IVUS) and 3-year clinical follow-up study was to compare the effects of EESs and ZESs on neointima volume and major adverse cardiovascular events (MACEs) such as death, myocardial infarction (MI), target lesion revascularization (TLR) and stent thrombosis in DES restenosis patients. Patients were eligible for this study if they were between 40 and 75 years old with in-stent restenosis >50% by quantitative coronary angiographic analysis in DES or within 5 mm of the stent edges with signs of ischaemia. Eligible patients (n = 304, 146 women and 158 men) were randomly assigned to receive either EES (158 patients) or ZES (146 patients). The primary endpoint of the study was to compare neointima volume between the EES and ZES groups at the 9-month follow-up IVUS. MACEs, including death, non-fatal MI, stent thrombosis and the need for repeated TLR within 3 years, were noted. The 9-month angiographic and IVUS follow-up showed no significant differences in late lumen loss (0.40 ± 0.56 vs. 0.45 ± 0.61 mm, P = 0.57, respectively) and neointima volume (0.51 ± 0.48 vs. 0.56 ± 0.54 mm3/1 mm, P = 0.47, respectively) in the EES and the ZES groups. Composite MACEs such as death, MI, stent thrombosis and TLR during 3-year follow-up were comparable between the two groups [15.8% (n = 25) in the EES group and 22.6% (n = 33) in the ZES group, P = 0.276], independent of de novo DES type, sex, age, body mass index, presence of diabetes, hypertension and dyslipidaemia. Patients with first- and second-generation DES restenosis, both EES and ZES implantation were effective and safe in reducing neointima volume and late loss with a comparable rate of MACEs independent of cardiovascular risk factors.

Effect of sitagliptin on plaque changes in coronary artery following acute coronary syndrome in diabetic patients: The ESPECIAL-ACS study

BackgroundDipeptidyl peptidase-4 (DPP-4) inhibitors have anti-atherosclerotic and cardioprotective effects in vitro. However, the impact of DPP-4 inhibitors on coronary plaque remains unclear. We sought to assess the effect of sitagliptin on coronary plaque volume (PV) and stabilization in diabetic patients with acute coronary syndrome (ACS). MethodsThe ESPECIAL-ACS was a prospective, randomized, open-label, parallel group study at 4 Japanese centers to assess the effect of 6-month treatment with sitagliptin on coronary plaque changes in non-culprit lesion in diabetic patients with ACS using serial intravascular ultrasound (IVUS) and integrated backscatter IVUS (IB-IVUS) analysis. ResultsA total of 41 patients were randomly allocated to either sitagliptin group (diet and exercise with sitagliptin 50–100mg daily, n=21) or control group (diet and exercise, n=20) within 72h after percutaneous coronary intervention, and underwent volumetric IVUS and IB-IVUS analyses at baseline and 6-month follow-up. At 6-month follow-up, the percent change in PV as primary endpoint was larger in the sitagliptin group than in the control group, but the difference was not statistically significant (−4.0±8.5% vs. −1.4±8.8%, p=0.35). In IB-IVUS analysis, the percent change in lipid PV significantly decreased in the sitagliptin group compared with the control group (−7.1±21.5% vs. 15.6±41.8%, p=0.03). ConclusionsCompared with diet and exercise therapy, sitagliptin did not significantly reduce coronary PV in diabetic patients with ACS at 6-month follow-up. However, the percent change in lipid PV significantly decreased in the sitagliptin group, suggesting that sitagliptin has a potential to stabilize the plaque vulnerability.

EARLY CORONARY ENDOTHELIAL DYSFUNCTION PREDICTS ACCELERATED PLAQUE PROGRESSION 1 YEAR AFTER CARDIAC TRANSPLANTATION: SERIAL VOLUMETRIC EVALUATION BY INTRAVASCULAR ULTRASOUND

Relationship between the presence of endothelial dysfunction at the time of transplantation and later development of cardiac allograft vasculopathy (CAV) as assessed by serial volumetric intravascular ultrasound (IVUS) analysis has not been reported. Intracoronary acetylcholine (Ach) infusion was

Chronic vascular response after self-expanding nitinol stent implantation in superficial femoral arteries: a serial intravascular ultrasound analysis

The mechanical properties of the self-expanding nitinol stents (SENS) and chronic biological stimulation on the wall from the SENS have not been fully investigated. This study evaluated the mechanical vascular response to SENS implantation in superficial femoral artery (SFA) lesions using serial volumetric intravascular ultrasound (IVUS). Twenty-five symptomatic patients due to de novo SFA lesions scheduled for SENS placement were prospectively enrolled. Serial IVUS studies were performed immediately after crossing with a guidewire, immediately after the procedure, and at a 8-month follow-up. Serial IVUS volumetric analysis was conducted after stent deployment and at follow-up. Mean stent, lumen and neointimal areas were calculated as the volume divided by the stent length, and the calcium arc was measured. At follow-up, SENS had increased 40.6% in overall volume. The chronic stent expansion tended to be larger, and the mean neointimal area at the 8-month follow-up was significantly larger in less calcified lesions compared to heavily calcified lesions. As a result, the mean late lumen area loss was significantly larger in lesions with calcium arcs of 0° and in the first and second quadrants than in those with calcium arcs in the third and fourth quadrants (2.8±7.2, 1.3±5.6, 0.6±5.9, 1.2±5.4, -0.8±5.2 mm(2), respectively; p<0.001). SENSs continued to enlarge with intimal proliferation over 8months in all lesions. Although arterial calcium affected the degree of chronic stent expansion during the follow-up period, neointimal proliferation was smaller in heavily calcified lesion compared to less calcified lesion following SENS implantation.

Effects of celecoxib on vascular changes after coronary intervention: A serial volumetric intravascular ultrasound analysis from the mini-COREA randomized clinical trial

Effects of celecoxib on vascular changes after coronary intervention: A serial volumetric intravascular ultrasound analysis from the mini-COREA randomized clinical trial

Coronary plaque progression of non-culprit lesions after culprit percutaneous coronary intervention in patients with moderate to advanced chronic kidney disease: intravascular ultrasound and integrated backscatter intravascular ultrasound study.

Previous studies have suggested that the deterioration of renal function increases the risk of major adverse clinical events not only in culprit lesions but also in non-culprit lesions (NCLs) after percutaneous coronary intervention (PCI). This study evaluated serial coronary plaque change of NCL in patients with different stages of chronic kidney disease (CKD) using intravascular ultrasound (IVUS) and integrated backscatter IVUS (IB-IVUS). In 113 patients (113 NCLs) underwent both IVUS-guided PCI and follow-up IVUS, volumetric IVUS analyses were performed at proximal reference NCLs in de novo target vessels post PCI and at 8-month follow-up. NCLs were divided into 4 groups based on baseline CKD stage: CKD-1, n = 18; CKD-2, n = 42; CKD-3, n = 29; and CKD4–5, n = 24. We compared serial changes of plaque burden and composition among groups under statin treatment. Plaque progression occurred in CKD-3 (+4.6 mm3, p < 0.001) and CKD4–5 (+9.8 mm3, p < 0.001) despite anti-atherosclerotic treatment, whereas plaque regression occurred in CKD-1 (−5.4 mm3, p = 0.002) and CKD-2 (−3.2 mm3, p = 0.001) mainly due to initiate statin treatment after PCI. Plaque volume change was correlated with eGFR (p < 0.0001). Multivariate analysis showed CKD stage 3–5 was an independent predictor of plaque progression. Regarding IB-IVUS analyses, lipid plaque increased in CKD-3 (+4.6 mm3, p < 0.001) and CKD4–5 (+5.4 mm3, p < 0.001), but decreased in CKD-2 (−2.7 mm3, p < 0.05). Fibrotic plaque also increased in CKD4–5 (+3.4 mm3, p < 0.001). Moderate to advanced CKD was associated with coronary plaque progression characterized by greater lipid and fibrotic plaque volumes in NCL under statin treatment after culprit PCI.

Relationship between fractional flow reserve and residual plaque volume and clinical outcomes after optimal drug-eluting stent implantation: Insight from intravascular ultrasound volumetric analysis

BackgroundThe underlying cause of FFR reduction and prognostic impact of FFR after optimal DES implantation remain unknown. The study aims were to use intravascular ultrasound (IVUS) to investigate the mechanism responsible for reduced fractional flow reserve (FFR) after optimal drug-eluting stent (DES) implantation and to evaluate FFR effect on clinical outcomes after optimal percutaneous coronary intervention with DES. MethodsNinety-seven patients treated with optimal DES implantation under IVUS and pullback FFR guidance were followed clinically (median 17.8months). Post-stenting IVUS examination and pullback FFR recording were performed, and angiographic and IVUS parameters associated with reduced FFR were evaluated. The composite of major adverse cardiac events (MACE), including cardiac death, myocardial infarction, stent thrombosis, and target vessel revascularization, was analyzed. ResultsRegression analysis showed inverse correlations between post-stent FFR and residual plaque volume index (r=−0.40, p<0.01) and residual percent plaque volume (r=−0.68, p<0.01) in IVUS but no correlation of minimal lesion diameter with quantitative coronary angiography (r=0.07, p=0.50) or IVUS-derived minimal stent area (r=0.02, p=0.84). MACE was observed in 10 patients (10.3%), and FFR after optimal stenting was significantly lower in this group (0.86±0.04 vs 0.91±0.04, p<0.01). The optimal FFR threshold for predicting MACE was 0.90, identified by the receiver operating characteristic curve. ConclusionsReduced FFR after optimal DES implantation was associated with residual plaque volume identified by IVUS and future adverse cardiac events.

Effect of Bare-Metal Nitinol Stent Implantation and Paclitaxel-Eluting Nitinol Stent Implantation on Vascular Response in the Superficial Femoral Artery Lesion Assessed on Intravascular Ultrasound

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

Relationship between intravascular ultrasound parameters and fractional flow reserve in intermediate coronary artery stenosis of left anterior descending artery: Intravascular ultrasound volumetric analysis

The objective of this study was to assess the relationship between intravascular ultrasound (IVUS) parameters, including volumetric analysis, and fractional flow reserve (FFR). Although it is known that coronary atherosclerosis burden measured by IVUS volumetric analysis is related with clinical outcomes, its relationship with functional significance remains unknown. Both IVUS and FFR were performed in 206 cases of intermediate stenosis of the left anterior descending artery (LAD). Myocardial ischemia was assessed by FFR and maximal hyperemia was induced by continuous intracoronary adenosine infusion. FFR < 0.80 was considered as significant inducible myocardial ischemia. We performed standard IVUS parameter measurements and volumetric analyses. IVUS parameter comparison was performed in the presence (n = 90) or absence (n =116) of significant myocardial ischemia. Lesions with minimal lumen area (MLA) ≥ 4.0 mm2 had FFR ≥ 0.80 in 91.4% of cases, while 50.9% of lesions with MLA < 4.0 mm2 had FFR < 0.80. The independent predictors of FFR < 0.80 were IVUS lesion length (odds ratio [OR]: 1.1, 95% confidence interval [CI] = 1.06–1.18, P < 0.001) and MLA significance according to the lesion location (OR: 7.01, 95% CI = 3.09–15.92, P = 0.001). FFR correlated with plaque volume (r = −0.345, P < 0.001) and percent atheroma volume (PAV) (r = −0.398, P < 0.001). Lesions with significant ischemia (FFR < 0.80) as compared to those with FFR > 0.80 were associated with larger plaque volume (181.8 ± 82.3 vs. 125.9 ± 77.9 mm3, P < 0.001) and PAV (58.9 ± 5.6 vs. 53.8 ± 7.9%, P < 0.001). IVUS parameters representing severity and extent of atheromatous plaque correlated with functional significance in LAD lesions with intermediate stenosis.

Pattern of instent neointimal formation compared to native atherosclerosis in the coronary bifurcation lesions: volumetric intravascular ultrasound analysis

Background No clinical study has systematically analyzed and compared circumferential neointimal and plaque distribution of stent neointimal proliferation and in native atherosclerotic plaques. This study aimed to investigate and compare the pattern of instent neointimal formation and native atherosclerosis in the coronary bifurcation lesions by volumetric analysis using systematic intravascular ultrasound (IVUS). Methods We examined bifurcation lesions in native coronary artery (plaque group, n=102) and stented bifurcations at 9-month follow-up (neointima group, n=51) using volumetric IVUS analysis of both the main vessel (MV) and side branch (SB). Three 5-mm segments were analyzed; the proximal MV (MVp), distal MV (MVd) and SB ostium (SBo). For each segment, volumetric analysis was performed in each of four quadrants (divided according to the branch takeoff and the geometric center of the lumen); carinal, epicardial, abcarinal, and myocardial. The eccentricity index was defined as the ratio of the abcarinal plaque (or neointimal) volume to the carinal plaque (or neointimal) volume. Results The plaque distribution differed significantly between the four quadrants, with the largest in the abcarinal quadrant, followed by the myocardial, epicardial, and carinal quadrants. The distribution of neointima was similar in the MV, but the four quadrants in the SB did not differ significantly. The eccentricity indices of both the MVd (P &lt;0.001) and SBo (P=0.001) were significantly higher for the plaque group than the neointima group. Conclusions The distribution of neointimal proliferation seems to have a similar pattern to that of atherosclerotic plaque in native coronary arteries, particularly in the main vessel, but the trend is less prominent.

Impact of Kissing Balloon Inflation on the Main Vessel Stent Volume, Area, and Symmetry After Side-Branch Dilation in Patients With Coronary Bifurcation Lesions: A Serial Volumetric Intravascular Ultrasound Study

Intravascular ultrasound (IVUS) was performed to investigate the impact of kissing balloon inflation (KBI) on the main vessel (MV) stent volume, area, and symmetry after side-branch (SB) dilation in patients with coronary bifurcation lesions (CBL). It remains controversial whether KBI would restore the MV stent area and symmetry loss after SB dilation. A total of 88 serial IVUS examinations of the MV were performed after MV angioplasty, MV stenting, SB dilation, and KBI in 22 patients with CBL. The MV stent was divided into proximal, bifurcation, and distal segments; the stent volume index (SVI), minimal stent area (MSA), stent symmetry index (SSI), and external elastic membrane (EEM) volume index were measured in 198 stent segments and compared after MV stenting, SB dilation, and KBI. In the bifurcation segment, SVI, MSA, and SSI were significantly smaller after SB dilation than after MV stenting and KBI (SVI was 6.10 ± 1.50 mm(3)/mm vs. 6.68 ± 1.60 mm(3)/mm and 6.57 ± 1.60 mm(3)/mm, respectively, p < 0.05; MSA was 5.15 ± 1.30 mm(2) vs. 6.08 ± 1.40 mm(2) and 5.86 ± 1.50 mm(2), respectively, p < 0.05; and SSI was 0.78 ± 0.02 mm(2) vs. 0.87 ± 0.03 mm(2) and 0.84 ± 0.03 mm(2), respectively, p < 0.05). KBI restored the MV SVI, MSA, and SSI after SB dilation. In the proximal segment, SVI, MSA, and EEM volume index were significantly larger, but SSI was smaller after KBI than after MV stenting and SB dilation. In the distal segment, neither SB dilation nor KBI had a significant impact on the MV stent volume or symmetry. This is the first comprehensive volumetric IVUS analysis of CBL, to our knowledge, demonstrating that KBI restores the MV stent volume, area, and symmetry loss after SB dilation in the bifurcation segment, and induces asymmetric stent expansion in the proximal segment.

Effect of combination therapy of ezetimibe and rosuvastatin on regression of coronary atherosclerosis in Japanese patients with stable coronary artery disease

Background: Recent clinical trials have demonstrated that intensive low-density lipoprotein-cholesterol (LDL-C) lowering therapy by strong statins could prevent recurrent cardiovascular event and have beneficial regressive effects on coronary plaques. Otherwise, the use of ezetimibe in combination with statin has been reported to provide greater reduction in LDL-C level than statin monotherapy. However, it is not established whether additional LDL-C lowering achieved with the addition of ezetimibe to statin monotherapy will lead to further reduction in coronary plaque volume. Methods: In this prospective, open-label, randomized study, 40 patients with stable coronary artery disease (CAD) requiring percutaneous coronary intervention (PCI), whose LDL-C levels were higher than 100 mg/dl, were divided into combination therapy group (n=21, rosuvastatin 5mg plus ezetimibe 10mg daily) or statin monotherapy group (n=19, rosuvastatin 5mg daily). Serial volumetric intravascular ultrasound (IVUS) analysis were performed at baseline and after 6 months of follow-up for a non-PCI site. Results: LDL-C level was significantly decreased by 54.1% in the combination group (from 132.7±31.7 mg/dl to 59.5±17.1 mg/dl, p<0.001) vs. 42.1% in the monotherapy group (from 122.0±15.7 mg/dl to 69.1±19.7 mg/dl, p<0.001). Plaque volume (PV) was significantly reduced in the combination group (14.2±12.9% decrease) compared with the monotherapy group (2.1±17.0% decrease; p=0.016). Moreover, percent change in PV showed a significantly positive correlation with percent change and nominal change of LDL-C (r=0.403, p=0.011, and r=0.418, p=0.008, respectively), and percent change of non high-density lipoprotein cholesterol (r=0.380, p=0.024). It also showed a significant positive correlation with follow-up small dense LDL level (r=0.455, p=0.006). Conclusions: Aggressive LDL-C lowering therapy by ezetimibe in addition to statin may exert significant regression of coronary plaque volume compared with usual-dose statin monotherapy in patients with stable CAD.

Implications of age in coronary artery disease progression. A serial, volumetric, intravascular ultrasound study

Background: The implications of age on clinical and angiographic manifestations of coronary artery disease are well established. Elderly Patients (P) are classically under-represented in clinical trials and are less likely to be fully investigated and to receive well established therapies. However, the potential influence of age on atherosclerosis progression remains poorly defined. Objective: The purpose of this study was to determine the relationship between age and the extent of coronary atherosclerosis and its progression rate. Methods: 200 consecutive P (mean age 65±10 years, 45 [22%] female) undergoing Serial Intravascular Ultrasound (IVUS) studies (median time interval 366 days) were analyzed. Of these, 39 P (19,5%) were ≥ 75 years of age (elderly). A validated system for volumetric IVUS analysis (EchoScan, TOMTEC) was used for off-line three-dimensional reconstruction and volumetric analysis. Both age groups were compared with regard to baseline characteristics, coronary atheroma burden, and disease progression at follow-up. Study end-points were absolute and percent change (delta) in plaque volume as detected by IVUS. Results: Elderly P had a more adverse cardiovascular risk profile, including diabetes and hypertension. Despite this adverse clinical profile, medical therapy was similar in both groups. However, baseline Total Atheroma Volume (TAV) and Percent AtheromaVolume (PAV) were similar in both groups. Furthermore, at late follow-up, changes in TAV and PAV were also similar in both groups. View this table: Table 1. Clinical characteristics and changes in atheroma burden according to age Conclusions: Despite an adverse clinical profile elderly P with established coronary artery disease have a similar extent of coronary atheroma burden than younger P. Coronary atheroma progression is also similar in both age groups, emphasizing the need for implementing of aggressive preventive therapeutic strategies irrespective of P age.

ASSA13-15-3 The Pattern of Instent Neointimal Formation Compared to Native Atherosclerosis in the Coronary Bifurcation Lesions: Volumetric Intravascular Ultrasound Analysis

Objective To investigate and compare the pattern of instent neointimal formation and native atherosclerosis in the coronary bifurcation lesions by volumetric analysis using systematic intravascular ultrasound (IVUS). Methods This study examined 102 native coronary artery bifurcation lesions and 51 post-stenting bifurcation lesions treated with drug-eluting stents using the T-stenting technique at 9-month follow-up IVUS images for both main vessel and side branch. Three interested segments were analysed: proximal main vessel (MVp) ostium, distal main vessel (MVd) and side branch ostium (SBo). At each segment, four quadrant analysis was performed per 1 mm by measuring the vessel area (stent area in the post-stenting lesions), lumen area and calculating the plaque area for volumetric analysis. Results In the plaque group, the plaque volume differed significantly between the four quadrants (P When the left main (LM) bifurcation (n = 38) was analysed separately, the abcarinal quadrant still had the largest plaque volume and the carinal quadrant the least in all three segments, while the epicardial and myocardial quadrant did not differ in the MVp (P = 0.99). In the MVd and SBo, the plaque volume of myocardial quadrant was still significantly greater than the epicardial quadrant (P In the neointima group, the neointimal volume differed significantly in the MVp and MVd (P = 0.002, P = 0.002, separately), while the four quadrants did not differ in the SB (P = 0.281). In the MVp and MVd, the neointimal volume was larger in the abcarinal than the carinal quadrant (in MVp, 4.8 mm3 [IQR 2.7.6.3 mm3] vs.2.1 mm3 [IQR 0.5.3.9 mm3], P When comparing the eccentricity indices between plaque and neointima groups, there was no difference in the MVp, while the neointima group was significantly smaller than plaque group in the MVd (1.6 [IQR 0.8, 2.8] vs. 4.7 [IQR 2.1, 8.7], P Conclusions The distribution of neointimal proliferation and seems to have a similar pattern to that of atherosclerotic plaque in native coronary arteries, particularly in the main vessel, but the trend is less prominent.

Comparison of Zotarolimus-eluting Stents with Sirolimus-eluting and Everolimus–eluting Stents in Patients with Long Coronary Artery Lesions Intimal Hyperplasia and Vascular Changes Assessed by Volumetric Intravascular Ultrasound Analysis

As a substudy of the large, randomized LONG-DES-III (Percutaneous Treatment of LONG Native Coronary Lesions With Drug-Eluting Stent-III) trial comparing first- and second-generation drug-eluting stents, we sought to investigate intimal hyperplasia (IH) and vascular changes using volumetric intravascular ultrasound analysis.