Hokuriku-plus familial hypercholesterolaemia registry study: rationale and study design.

INTRODUCTION: Familial hypercholesterolaemia (FH) is an autosomal-dominant inherited genetic disease. It carries an extremely high cardiovascular risk associated with significantly elevated low-density lipoprotein (LDL) cholesterol. The diagnostic rate of this disease in some European nations is quite high, due to the presence of multiple prospective registries. On the other hand, few data-and in particular multicentre data-exist regarding this issue among Japanese subjects. Therefore, this study intends to assemble a multicentre registry that aims to comprehensively assess cardiovascular risk among Japanese FH patients while taking into account their genetic backgrounds. METHODS AND ANALYSIS: The Hokuriku-plus FH registry is a prospective, observational, multicentre cohort study, enrolling consecutive FH patients who fulfil the clinical criteria of FH in Japan from 37 participating hospitals mostly in Hokuriku region of Japan from April 2020 to March 2024. A total of 1000 patients will be enrolled into the study, and we plan to follow-up participants over 5 years. We will collect clinical parameters, including lipids, physical findings, genetic backgrounds and clinical events covering atherosclerotic and other important events, such as malignancies. The primary endpoint of this study is new atherosclerotic cardiovascular disease (ASCVD) events. The secondary endpoints are as follows: LDL cholesterol, secondary ASCVD events and the occurrence of other diseases including hypertension, diabetes and malignancies. ETHICS AND DISSEMINATION: This study is being conducted in compliance with the Declaration of Helsinki, the Ethical Guidelines for Medical and Health Research Involving Human Subjects, and all other applicable laws and guidelines in Japan. This study protocol has been approved by the Institutional Review Board at Kanazawa University. We will disseminate the final results at international conferences and in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: UMIN000038210.

Low Baseline High-Sensitive C-Reactive Protein is Associated with Coronary Atherosclerosis Regression: Insights from the MILLION Study.

AIM: The prospective, randomized, multicenter Myocardial Ischemia Treated with Percutaneous Coronary Intervention and Plaque Regression by Lipid Lowering & Blood Pressure Controlling assessed by Intravascular Ultrasonography (MILLION) study demonstrated that combined treatment with atorvastatin and amlodipine enhanced coronary artery plaque regression. Although the baseline high-sensitive C-reactive protein (hs-CRP) reportedly plays an important role in atherogenesis, few data exist regarding the relationship between hs-CRP and plaque regression in patients receiving a combined atorvastatin and amlodipine therapy. METHODS: A total of 68 patients (male, 55; mean age, 64.2 years) with baseline and follow-up 3-dimensional intravascular ultrasound examinations in the MILLION study were stratified by baseline hs-CRP level quartiles. The serial measurements of lipid, blood pressure, and percentage changes in the plaque volume were compared between the groups, and the factors associated with the percentage change in the plaque volume were assessed. RESULTS: There were no significant between-group differences in the extent of change in low-density lipoprotein cholesterol (LDL-C) or systolic and diastolic blood pressure after 18-24 months of treatment. The percentage change in the plaque volume showed a linear association with the baseline hs-CRP (p for trend ＜0.05); however, there was no correlation with changes in LDL-C or systolic and diastolic blood pressure. In the multiple regression analysis, the baseline hs-CRP level was independently associated with the percentage change in the plaque volume (ß=0.29, p=0.022). CONCLUSIONS: Coronary plaque regression was associated with the baseline hs-CRP level in patients treated with a combined lipid- and blood pressure-lowering therapy.

Limited effects of long-term enzyme replacement therapy on the cardiac conduction system in Fabry disease.

The long-term effects of enzyme replacement therapy (ERT) on cardiac function and the conduction system in Fabry disease are not clearly understood. We report a case of a 48-year-old man with non-classical Fabry disease treated with ERT for 11 years. He was diagnosed with Fabry disease at age 27 years based on the presence of decreased alpha-galactosidase A activity in the peripheral leukocytes and of the causal alpha-galactosidase A mutation (Val339Gln). Subsequently, peritoneal dialysis was initiated for renal failure at age 35 years. ERT was initiated at age 39 years to halt the progression of cardiac dysfunction. Electrical conduction disturbances progressed gradually to complete atrioventricular block with atrial standstill during 9 years of ERT despite the lack of progression of ventricular hypertrophy. Although he underwent permanent pacemaker implantation to prevent sudden cardiac death, the atrioventricular junctional rhythm remained, thereby lowering the ventricular pacing rate. Based on this case, we recognize that the effects of ERT are limited for inhibiting the progression of Fabry disease and especially for inhibiting arrhythmia and conduction disturbances. Early diagnosis of Fabry disease and early initiation of ERT might be the key to further improvements in this disease and its associated conditions. .

Overview of the 81st Annual Scientific Meeting of the Japanese Circulation Society　- Cardiovascular Medicine for the Next Generation.

The 81stAnnual Scientific Meeting of the Japanese Circulation Society was held in Kanazawa, Japan, on March 17-19, 2017 under a miraculously clear sky. The frontlines of healthcare and medicine are dramatically changing. Thus, "Cardiovascular Medicine for Next Generation" was chosen as the main theme of this meeting. The program was constructed around major identified issues, including renewal of our understanding of basic cardiovascular medicine, translational research, and preventive molecular medicine, all of which are anticipated to transcend the medical field over the next generation. Despite the provincial location, 15,672 participants, including more than 400 from overseas countries, attended the 3-day meeting, and there were in-depth discussions in the various sessions. In particular, to our great pleasure, Her Imperial Highness Princess Takamado kindly attended the opening ceremony and extended congratulations to us. The meeting successfully completed and we sincerely appreciate the great cooperation and support from all affiliates.

Effect of Reverse Vessel Remodeling on Regression of Coronary Atherosclerosis in Patients Treated With Aggressive Lipid- and Blood Pressure-Lowering Therapy　- Insight From MILLION Study.

BACKGROUND: The MILLION study, a prospective randomized multicenter study, revealed that lipid and blood pressure (BP)-lowering therapy resulted in regression of coronary plaque as determined by intravascular ultrasound (IVUS). In the present study we performed additional analysis to investigate the associated factors with regression of coronary plaque.Methods and Results:We investigated serial 3D IVUS images from 68 patients in the MILLION study. Standard IVUS parameters were assessed at both baseline and follow-up (18-24 months). Volumetric data were standardized by length as normalized volume. In patients with plaque regression (n=52), plaque volumenormalizedsignificantly decreased from 64.8 to 55.8 mm3(P<0.0001) and vessel volumenormalizedsignificantly decreased from 135.0 to 127.5 mm3(P=0.0008). There was no difference in lumen volumenormalizedfrom 70.1 to 71.8 mm3(P=0.27). There were no correlations between % changes in vessel volume and cholesterol or BP. On the other hand, negative correlations between % change in vessel volume and vessel volumenormalizedat baseline (r=-0.352, P=0.009) or plaque volumenormalizedat baseline (r=-0.336, P=0.01) were observed. CONCLUSIONS: The current data demonstrated that in patients with plaque regression treated by aggressive lipid and BP-lowering therapy, the plaque regression was derived from reverse vessel remodeling determined by vessel volume and plaque burden at baseline irrespective of decreases in lipids and BP.

Acute necrotizing eosinophilic myocarditis complicated by complete atrioventricular block promptly responded to glucocorticoid therapy.

Acute myocarditis is frequently accompanied with conduction disturbances. Complete atrioventricular (AV) block may occur in acute myocarditis, but rarely in eosinophilic myocarditis. Acute necrotizing eosinophilic myocarditis, the most severe form of eosinophilic myocarditis, is generally fatal, and rarely complicated by complete AV block. We report a case of a 66-year-old woman with acute necrotizing eosinophilic myocarditis who presented with general malaise and nausea. She suddenly fell into cardiogenic shock because of complete AV block and worsened heart failure. Ultrasound cardiography revealed pericardial effusion, edematous myocardium, and reduced contractility of the left ventricle. The biopsied specimens showed marked interstitial infiltration with predominant eosinophils accompanied with myocardial necrosis. Oral administration of glucocorticoid in moderate dose promptly resolved the complete AV block, her clinical symptoms, and cardiac function. We recognized that acute necrotizing eosinophilic myocarditis can be complicated by complete AV block. Steroid therapy could be effective in the treatment of conduction disturbance as well as myocardial inflammation. .

Impact of combined lipid lowering and blood pressure control on coronary plaque: myocardial ischemia treated by percutaneous coronary intervention and plaque regression by lipid lowering and blood pressure controlling assessed by intravascular ultrasonography (MILLION) study.

The aim of the study was to elucidate the aggressive reduction of both low-density lipoprotein cholesterol (LDL-C) and blood pressure (BP) reduced coronary atherosclerotic plaque volume compared with a standard treatment of LDL-C and BP in Japanese patients with coronary artery disease (CAD). This study is a prospective, randomized, and open-labelled with a blind-endpoint evaluation study. A total of 97 patients (81 men, mean age 62.0 ± 9.6) with CAD undergoing intravascular ultrasonography (IVUS)-guided percutaneous coronary intervention (PCI) were randomized, and 68 patients had IVUS examinations at baseline and at 18-24 months follow-up. Patients were randomly assigned to standard or aggressive strategies targeting LDL-C and a BP of 100 mg/dL and 140/90 mmHg vs. 70 mg/dL and 120/70 mmHg, respectively. The primary endpoint was the percent change in coronary plaque volume. Both standard and aggressive strategies succeeded to achieve target levels of LDL-C and BP; 74.9 ± 14.7 vs. 63.7 ± 11.9 mg/dL (NS) and 124.1 ± 9.4/75.8 ± 7.7 vs. 113.6 ± 9.6/65.8 ± 9.4 mmHg (systolic BP; NS, diastolic BP; p < 0.05), respectively. Both groups showed a significant reduction in the coronary plaque volume of -9.4 ± 10.7% and -8.7 ± 8.6% (NS) in standard and aggressive therapies, respectively. Both standard and aggressive intervention significantly regressed coronary plaque volume by the same degree, suggesting the importance of simultaneous reductions of LDL-C and BP for prevention of CAD.

Impact of Updated Diagnostic Criteria for Long QT Syndrome on Clinical Detection of Diseased Patients: Results From a Study of Patients Carrying Gene Mutations.

OBJECTIVES: In this study, we scored patients with long QT syndrome (LQTS) according to the different Schwartz diagnostic criteria from 1993, 2006, and 2011, and to examine the validation of the criteria in relevance to the frequency of LQTS-related gene mutation. BACKGROUND: Although updated diagnostic criteria have been used in clinical settings, few data exist regarding their impact on the diagnosis of LQTS. METHODS: We used a cohort of 132 patients who presented with prolonged QTc intervals and/or abnormal clinical history in cardiac screening and who underwent exercise stress testing. LQTS scores of ≥3.5 points according to the 2006 and the 2011 criteria were considered to indicate a high probability of LQTS, as opposed to the 4 points used by the 1993 criteria. The 2011 criteria were updated by adding the evaluation of the recovery phase of exercise. RESULTS: The 2011 criteria significantly increased the number of high probability patients (n = 62) compared with the 1993 criteria (n = 32; p = 0.0002) or the 2006 criteria (n = 36; p = 0.0014). The percentage of mutation carriers in those with an intermediate score, which was rather high using the 1993 (53%) and 2006 criteria (53%), was greatly reduced with the 2011 criteria (15%, p = 0.0014 vs. the 1993 criteria, and p = 0.0013 vs. the 2006 criteria). Among 54 mutation carriers, the 1993, the 2006, and the 2011 criteria identified a high probability of carriers in 25 patients (46% sensitivity and 91% specificity), 27 patients (50% sensitivity and 88% specificity), and 48 patients (89% sensitivity and 82% specificity), respectively. CONCLUSIONS: The use of the 2011 criteria will facilitate the diagnosis of LQTS and will decrease the number of false negative results.

Whole exome sequencing combined with integrated variant annotation prediction identifies a causative myosin essential light chain variant in hypertrophic cardiomyopathy.

BACKGROUND: The development of candidate gene approaches to enable molecular diagnosis of hypertrophic cardiomyopathy (HCM) has required extensive and prolonged efforts. Whole exome sequencing (WES) technologies have already accelerated genetic studies of Mendelian disorders, yielding approximately 30% diagnostic success. As a result, there is great interest in extending the use of WES to any of Mendelian diseases. This study investigated the potential of WES for molecular diagnosis of HCM. METHODS: WES was performed on seven relatives from a large HCM family with a clear HCM phenotype (five clinically affected and two unaffected) in the Kanazawa University Hypertrophic Cardiomyopathy Registry. Serial bioinformatics filtering methods as well as using combined annotation dependent depletion (CADD) score and high heart expression (HHE) gene data were applied to detect the causative variant. Moreover, additional carriers of the variant were investigated in the HCM registry, and clinical characteristics harboring the variant were collected and evaluated. RESULTS: WES detected 60020 rare variants in the large HCM family. Of those, 3439 were missense, nonsense, splice-site, or frameshift variants. After genotype-phenotype matching, 13 putative variants remained. Using CADD score and HHE gene data, the number of candidates was reduced to one, a variant in the myosin essential light chain (MYL3, NM_000258.2:c.281G>A, p.Arg94His) that was shared by the five affected subjects. Additional screening of the HCM registry (n=600) identified two more subjects with this variant. Serial assessments of the variant carriers revealed the following phenotypic characteristics: (1) disease-penetrance of 88%; (2) all clinically affected carriers exhibited asymmetric septal hypertrophy with a substantial maximum left ventricular wall thickness of 18±3mm without any obstruction. CONCLUSIONS: WES combined with CADD score and HHE gene data may be useful even in HCM. Furthermore, the MYL3 Arg94His variant was associated with high disease penetrance and substantial interventricular septal hypertrophy.

Functional Characterization of Rare Variants Implicated in Susceptibility to Lone Atrial Fibrillation.

BACKGROUND: Few rare variants in atrial fibrillation (AF)-associated genes have been functionally characterized to identify a causal relationship between these variants and development of AF. We here sought to determine the clinical effect of rare variants in AF-associated genes in patients with lone AF and characterized these variants electrophysiologically and bioinformatically. METHODS AND RESULTS: We screened all coding regions in 12 AF-associated genes in 90 patients with lone AF, with an onset of 47±11 years (66 men; mean age, 56±13 years) by high-resolution melting curve analysis and DNA sequencing. The potassium and sodium currents were analyzed using whole-cell patch clamping. In addition to using 4 individual in silico prediction tools, we extended those predictions to an integrated tool (Combined Annotation Dependent Depletion). We identified 7 rare variants in KCNA5, KCNQ1, KCNH2, SCN5A, and SCN1B genes in 8 patients: 2 of 8 probands had a family history of AF. Electrophysiological studies revealed that 2 variants showed a loss-of-function, and 4 variants showed a gain-of-function. Five of 6 variants with electrophysiological abnormalities were predicted as pathogenic by Combined Annotation Dependent Depletion scores. CONCLUSIONS: In our cohort of patients with lone AF, 7 rare variants in cardiac ion channels were identified in 8 probands. A combination of electrophysiological studies and in silico predictions showed that these variants could contribute to the development of lone AF, although further in vivo study is necessary to confirm these results. More than half of AF-associated rare variants showed gain-of-function behavior, which may be targeted using genotype-specific pharmacological therapy.

Impact of combined lipid lowering with blood pressure control on coronary plaque regression: rationale and design of MILLION study.

A line of epidemiological studies suggests that the accumulation of coronary risk factors promotes the progression of coronary atherosclerosis. Recent clinical studies showed that aggressive low-density lipoprotein (LDL) cholesterol-lowering therapy using statins could regress coronary atheroma and reduce major cardiovascular events. Additionally, therapy that controlled amlodipine-based blood pressure reduced major cardiovascular events in patients with hypertension compared with an atenolol-based regimen. An open-label randomized multicenter study is primarily planned to evaluate the changes in coronary atheroma volume using intravascular ultrasonography 18-24 months after intensive lowering of LDL-cholesterol and blood pressure compared with a standard therapy indicated by current guidelines in Japanese patients with coronary artery disease (CAD). The secondary endpoints include changes in serum lipid levels, inflammatory markers, glucose markers and blood pressure. In total, 100 subjects with CAD who are undergoing percutaneous coronary intervention will be tested. The MILLION study will provide new evidence and therapeutic standards for the prevention of CAD in Japanese patients by controlling both LDL-C levels and blood pressure.

Impact of lesion morphology and associated procedures for left main coronary stenting on angiographic outcome after intervention: sub-analysis of Heart Research Group of Kanazawa, HERZ, Study.

Whether the lesion morphology and associated interventional procedures for the left main coronary artery disease (LMCA) could affect clinical outcome is still controversial. Therefore, we examined the impact of lesion morphology and associated procedures on clinical and angiographic outcomes of stenting for the LMCA. Among 7,660 patients with coronary intervention registered, we analyzed early angiographic results of 228 patients (179 men, mean age 69.4 years) concerned with LMCA lesions. In 121 out of 228 patients having long-term angiographic results, we examined the occurrence of major adverse coronary events (MACE) particularly in terms of the presence of acute coronary syndrome (ACS), the kind of stents, bear metal or drug eluting, the lesion morphology and associated procedures. Early angiographic success rate of LMCA stenting was 100 %, and clinical success rate was 94.3 %. During follow-up period for 3 years, MACE was observed in 17 patients. Under these conditions, multiple stenting (p < 0.01) and complicated procedures such as such as Y-stent, T-stent and crush stent (p < 0.01) were listed as risks for MACE, although there was no statistical difference in kinds of stent. Multivariate analysis demonstrated the significant disadvantage of complicated procedures using the bear metal stent on the occurrence of MACE (p < 0.01). These results demonstrate that the complicated procedures have great impact on clinical and angiographic outcomes after stenting for LMCA lesions, and suggest the simple procedure with a single stent for LMCA lesions in the present cohort. Whether the presence of ACS can affect the prognosis should further be sought.

Current perspectives in genetic cardiovascular disorders: from basic to clinical aspects.

We summarize recent advances in the clinical genetics of hypercholesterolemia, hypertrophic cardiomyopathy (HCM), and lethal arrhythmia, all of which are monogenic cardiovascular diseases being essential to understanding the heart and circulatory pathophysiology. Among the issues of hypercholesterolemia which play a pivotal role in development of vascular damages, familial hypercholesterolemia is the common genetic cardiovascular disease; in addition to identifying the gene mutation coding low-density lipoprotein receptor, lipid kinetics in autosomal recessive hypercholesterolemia as well as in proprotein convertase subtilisin/kexin 9 gene mutation were recently demonstrated. As for HCM, some gene mutations were identified to correlate with clinical manifestations. Additionally, a gene polymorphism of the renin-angiotensin system in development of heart failure was identified as a modifier gene. The lethal arrhythmias such as sudden death syndromes, QT prolongation, and Brugada syndrome were found to exhibit gene mutation coding potassium and/or sodium ion channels. Interestingly, functional analysis of these gene mutations helped to identify the role of each gene mutation in developing these cardiovascular disorders. We suggest considering the genetic mechanisms of cardiovascular diseases associated with hyperlipidemia, myocardial hypertrophy, or lethal arrhythmia in terms of not only clinical diagnosis but also understanding pathophysiology of each disease with therapeutic aspects.

Sarcomere gene mutations are associated with increased cardiovascular events in left ventricular hypertrophy: results from multicenter registration in Japan.

OBJECTIVES: This study investigated the occurrence of cardiovascular events in patients with hypertensive heart disease (HHD) or hypertrophic cardiomyopathy (HCM) with or without sarcomere gene mutations. BACKGROUND: Although HHD and HCM are associated with left ventricular hypertrophy (LVH), few data exist regarding the difference in prognosis between them. METHODS: We enrolled 256 patients with LVH (>13 mm) screened for sarcomere gene mutations. We divided them into 3 groups: the first had HHD without sarcomere gene mutations (group H), the second had sarcomere gene mutations (group G), and the third had neither sarcomere gene mutations nor HHD (group NG). We compared the occurrence of sudden cardiac death, ventricular tachycardia/fibrillation, admission for heart failure, and atrial fibrillation for 1 year. RESULTS: Group G (n = 78, 36 men; mean age, 53.4 years) experienced more total cardiovascular events than group H (n = 45, 32 men; mean age, 67.4 years) (p = 0.042) after adjustments for age and sex, although there was no significant difference in total cardiovascular events between groups H and NG (n = 98, 66 men; mean age, 62.0 years). With Kaplan-Meier analysis, group G exhibited a significantly higher incidence of admission for heart failure (p = 0.017) and atrial fibrillation (p = 0.045) than group H in those 50 years of age and older. Additionally, there was a significant difference in total cardiovascular events between groups G and NG (p = 0.021). CONCLUSIONS: These results demonstrate that HCM with sarcomere gene mutations can be associated with increased cardiovascular events compared with HHD or HCM without sarcomere gene mutations.

Impact of systolic dysfunction in genotyped hypertrophic cardiomyopathy.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is a disease of the sarcomere, and approximately 5% of cases of HCM show systolic dysfunction with poor prognosis. Few data exist regarding the systolic dysfunction in a large population of genotyped HCM subjects. HYPOTHESIS: The aim of this study was to assess the systolic dysfunction and prognosis in sarcomere gene mutation carriers. METHODS: The study included 157 sarcomere gene mutation carriers from 69 unrelated HCM families (87 males; mean age, 46.5 ± 20.5 years). After exclusions for systolic dysfunction at baseline, 107 subjects underwent serial echocardiograms. RESULTS: At a mean follow-up of 7.0 years, 12 subjects experienced systolic dysfunction. In multivariate Cox analysis, systolic dysfunction was related to age and ejection fraction at initial evaluation (P < 0.001 and P = 0.020, respectively), and was associated with the absence of mutations in the cardiac myosin-binding protein C gene (MYBPC3) (P = 0.042). When the subjects were divided into MYBPC3 and non-MYBPC3 mutation carriers, and time from birth to development of systolic dysfunction was compared, the rate of systolic dysfunction was higher in the non-MYBPC3 group than in MYBPC3 group (Kaplan-Meier, log-rank test, P = 0.010). After the onset of systolic dysfunction, 11 of 12 subjects died during a mean follow-up of 8.3 years. CONCLUSIONS: Non-MYBPC3 mutation carriers developed left ventricular systolic dysfunction more frequently than MYBPC3 mutation carriers, and the majority of sarcomere gene mutation carriers with systolic dysfunction had fatal outcomes during follow-up. This suggests that subjects with mutations in sarcomeric genes require careful management for systolic dysfunction.

A novel mutation in the transmembrane nonpore region of the KCNH2 gene causes severe clinical manifestations of long QT syndrome.

BACKGROUND: Long QT syndrome (LQTS) is characterized by prolonged ventricular repolarization and variable clinical course with arrhythmia-related syncope and sudden death. Mutations in the nonpore region of the LQTS-associated KCNH2 gene (also known as hERG) are mostly associated with coassembly or trafficking abnormalities, resulting in haplotype insufficiency and milder clinical phenotypes compared with mutations in the pore domain. OBJECTIVE: To investigate the effect of a nonpore mutation on the channel current, which was identified from an LQTS family with severe clinical phenotypes. METHODS: Two members of a Japanese family with LQTS were searched for mutations in KCNQ1, KCNH2, SCN5A, KCNE1, KCNE2, and KCNJ2 genes by using automated DNA sequencing. We characterized the electrophysiological properties and glycosylation pattern of the mutant channels by using patch clamp recording and Western blot analysis. RESULTS: In the LQTS patient with torsades de pointes and cardiopulmonary arrest, we identified the novel T473P mutation in the transmembrane nonpore region of KCNH2. The proband's father carried the same mutation and showed prolonged corrected QT interval and frequent torsades de pointes in the presence of hypokalemia following the administration of garenoxacin. Patch clamp analysis in heterologous cells showed that hERG T473P channels generated no current and exhibited a dominant negative effect when coexpressed with wild-type protein. Only incompletely glycosylated hERG T473P channels were observed by using Western blot analysis, suggesting impaired trafficking. CONCLUSIONS: These results demonstrated that a trafficking-deficient mutation in the transmembrane nonpore region of KCNH2 causes a dominant negative effect and a severe clinical course in affected patients.

Impact of out-stent plaque volume on in-stent intimal hyperplasia: results from serial volumetric analysis with high-gain intravascular ultrasound.

BACKGROUND: Changes in out-stent plaque volume can be related to in-stent intimal hyperplasia. However, few data exist regarding the impact of out-stent plaque volume on in-stent intimal hyperplasia. METHODS: We prospectively performed volumetric intravascular ultrasound in 46 stable coronary patients (34 males, mean age of 66 years) immediately as well as 18 months after stenting. From the high-gain ultrasound images, out-stent plaque volume was calculated by extracting the stent volume from the external elastic membrane volume. Volumes of in-stent intimal hyperplasia and reference plaque were also evaluated. RESULTS: Out-stent plaque volume increased from 177.3 ± 100.8mm(3) to 190.7 ± 111.1mm(3) (p<0.05) in correlation with increases in-stent intimal hyperplasia (r=0.536, p<0.05). Under these conditions, changes in reference plaque volume correlated with those in LDL-C, which decreased from 121.2 ± 48.0mg/dl to 103.3 ± 48.9 mg/dl (r=0.43, p<0.05). Interestingly, increases in out-stent plaque volume in the silorimus-eluting stent (2.7 ± 1.2%) were lesser than those in the bare-metal stent (14.0 ± 11.0%, p<0.05). CONCLUSIONS: These results indicate that irrespective of LDL-C level, changes in out-stent plaque volume correlate with those in in-stent intimal hyperplasia. We suggest that silorimus-eluting stent can suppress in-stent intimal hyperplasia partially by affecting out-stent plaque, although further large-scale studies are required to define the role of out-stent plaque in the occurrence of in-stent intimal hyperplasia.

Intravascular ultrasound appearance of scattered necrotic core as an index for deterioration of coronary flow during intervention in acute coronary syndrome.

In acute coronary syndrome (ACS) patients with deterioration of coronary flow during percutaneous coronary intervention (PCI), a scattered necrotic core pattern (SNC) is observed by intravascular ultrasound virtual histology (VH-IVUS). The purpose of this study was to evaluate the impact of SNC on deterioration of coronary flow during PCI in ACS. A total of 38 ACS patients were imaged using VH-IVUS before PCI. In addition to conventional definitions of thin-cap fibroatheroma by VH-IVUS (ID-TCFA), the SNC was defined as necrotic core foci with a maximum diameter of <14 pixels on a 400 × 400 VH-IVUS image in the presence of >50% plaque burden except in the ID-TCFA frame. Patients were divided into deterioration of coronary flow group (n = 15) and normal-reflow group (n = 23). The incidence of residual thrombus and plaque rupture, the external elastic membrane, plaque and fibrous volumes, the incidence of ID-TCFA and the average number of SNC per frame was significantly greater in deterioration of coronary flow group than in normal-reflow group (all parameters P < 0.05). Multivariate analysis revealed that the average number of SNC per frame was independently associated with deterioration of coronary flow in ACS patients (odds ratio 1.18, P < 0.05). In conclusion, an increased number of SNC is associated with deterioration of coronary flow during PCI in ACS patients.