Circulation Journal
Online ISSN : 1347-4820
Print ISSN : 1346-9843
ISSN-L : 1346-9843
Volume 76 , Issue 7
Showing 1-45 articles out of 45 articles from the selected issue
Message From the Editor-in-Chief
Cardiology Societies in the Asian/Pacific Region
International COI Statement
  • Fernando Alfonso, Adam Timmis, Fausto J. Pinto, Giuseppe Ambrosio, Hug ...
    2012 Volume 76 Issue 7 Pages 1542-1549
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: May 24, 2012
    JOURNALS FREE ACCESS
    Disclosure of potential conflicts of interest (COI) is used by biomedical journals to guarantee credibility and transparency of the scientific process. COI disclosure, however, is not systematically nor consistently dealt with by journals. Recent joint editorial efforts paved the way towards the implementation of uniform vehicles for COI disclosure. This paper provides a comprehensive editorial perspective on classical COI-related issues. New insights into current COI policies and practices among European Society of Cardiology national cardiovascular journals, as derived from a cross-sectional survey using a standardised questionnaire, are discussed.  (Circ J 2012; 76: 1542–1549)
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Reviews
  • Harvey Feigenbaum, Ronald Mastouri, Stephen Sawada
    2012 Volume 76 Issue 7 Pages 1550-1555
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: June 09, 2012
    JOURNALS FREE ACCESS
    Left ventricular (LV) evaluation is the most important use of echocardiography. Speckle tracking strain echocardiography (SE) provides a quantitative regional and global LV assessment, is an independent supplement to wall motion analysis and has been validated over the past 10 years. Despite these facts, SE is not being used routinely, especially in the United States. SE can generate longitudinal, radial, and circumferential strain measurements and LV twist. Although intriguing and potentially useful, these measurements also are confusing, complicated, time consuming, and frequently displayed as difficult-to-interpret wave forms. A pragmatic approach to SE simplifies the suggested method for strain calculation to reduce the time required and enhance reproducibility. With this modification the strain calculations take only 2–4min. The yield is >80% in all patients. Reproducibility is at least as good as ejection fraction. Longitudinal strain is the most sensitive and reproducible of the various strain measurements, so it is the only strain we record. For simplicity, systolic strain is displayed as a positive number. Lastly, we primarily use a bullseye presentation for peak systolic strain. Many clinical examples are illustrated. However, as with all tests, SE is not perfect; there are limitations and potential false positives, but a practical approach to SE eventually should help make it a part of all echocardiographic examinations.  (Circ J 2012; 76: 1550–1555)
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  • – A Diagnostically Challenging Cardiomyopathy –
    Timothy E. Paterick, A. Jamil Tajik
    2012 Volume 76 Issue 7 Pages 1556-1562
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: June 05, 2012
    JOURNALS FREE ACCESS
    Supplementary material
    Diagnosing left ventricular noncompaction (LVNC) cardiomyopathy is a challenge for the medical community because the condition shares morphologic features of hypertrophic and dilated cardiomyopathies. The uncertainty surrounding the diagnosis of LVNC is related to the lack of a “perfect diagnostic tool,” such as a reproducible genetic marker. The diagnosis requires expertise in the broad spectrum of overlapping cardiomyopathies. The demarcation between LVNC and normal phenotypic variations is often indistinct. Echocardiography, used in routine clinical practice to identify the typical morphologic features of LVNC, can be overly sensitive and lack specificity with the presently defined measurements and ratios used to diagnose LVNC. The available diagnostic criteria show a propensity toward overdiagnosing LVNC. The complex clinical sequelae of atrial and ventricular arrhythmias, heart failure, thromboembolic events and sudden death associated with LVNC make a valid and reproducible diagnosis critical. The trend to using a morphologic/pathophysiologic, instead of a solely morphologic, approach holds promise in the quest for an accurate, reliable diagnosis of LVNC. We must understand the distinction between morphological findings and morphological findings with pathophysiology. Our future understanding of LVNC depends on an integration of cardiac morphology, physiology, pathophysiology and evolving genetics.  (Circ J 2012; 76: 1556–1562)
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  • Paola Berne, Josep Brugada
    2012 Volume 76 Issue 7 Pages 1563-1571
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: June 13, 2012
    JOURNALS FREE ACCESS
    Brugada syndrome (BS) is a cardiac disorder characterized by typical ECG alterations, and it is associated with a high risk for sudden cardiac death (SCD), affecting young subjects with structurally normal hearts. The prevalence of this disorder is still uncertain, presenting marked geographical differences. The syndrome has a genetic basis, and several mutations have been identified in genes encoding subunits of cardiac sodium, potassium, and calcium channels, as well as in genes involved in the trafficking or regulation of these channels. Most BS patients are asymptomatic, but those who develop symptoms present with syncope and/or SCD secondary to polymorphic ventricular tachycardia and/or ventricular fibrillation. Risk stratification is still challenging, especially in cases of asymptomatic BS patients. This is a brief review of recent advances in our understanding of the genetic and molecular bases of BS, arrhythmogenic mechanisms and clinical course, as well as an update of the tools for risk stratification and treatment of the condition.  (Circ J 2012; 76: 1563–1571)
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  • – Are We Helping or Hurting Our Patients? –
    Masaya Koshizaka, Jennifer B. Green, John H. Alexander
    2012 Volume 76 Issue 7 Pages 1572-1580
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: June 16, 2012
    JOURNALS FREE ACCESS
    Diabetes, which is a metabolic disorder with multiple comorbidities, increases the risk of cardiovascular disease. Although it was once assumed that controlling plasma glucose levels would reduce diabetes-related morbidity and mortality, recent trials have demonstrated that this is not consistently the case. Data from large, well-designed trials suggest that intensive glycemic therapy may be useful in preventing cardiovascular events if initiated early in the disease course, but may be harmful or not useful if applied to high-risk patients with a longer history of diabetes. Furthermore, the cardiovascular safety of existing individual antihyperglycemic agents remains largely unknown. We review the relationship between glycemic control targets and cardiovascular outcomes, as well as the current understanding of the cardiovascular effects of existing glucose-lowering therapies. This information has affected recommendations for diabetes care in Japan and the United States differently, and supports a more comprehensive and prospective approach to cardiovascular safety assessments of diabetes therapies in the future. Results from ongoing cardiovascular outcomes trials of diabetes medications may help to define optimal glucose-lowering strategies for patients at high risk of cardiovascular complications. Until then, glycemic control targets and the medications used to achieve them should be individualized according to each patient’s age, duration of diabetes, risk of hypoglycemia, risk of cardiovascular complications, and life expectancy.  (Circ J 2012; 76: 1572–1580)
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  • – What We Know and Don’t Know –
    Yoshihiro Onouchi
    2012 Volume 76 Issue 7 Pages 1581-1586
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: June 07, 2012
    JOURNALS FREE ACCESS
    Kawasaki disease (KD) is a leading cause of acquired heart disease in children in developed countries. Although it has been thought that symptoms of KD are related to hyperactivation of the immune system triggered by infection with some microorganisms, the etiological agent still remains unknown. In this situation, genetic factors underlying the disease pathogenesis, which have been suggested by epidemiological findings, are expected to be clues to the enigma. Recently, susceptibility genes for KD have been identified in succession by studies with a genome-wide approach. Recent advances in genetic studies for KD will be presented.  (Circ J 2012; 76: 1581–1586)
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Editorials
Original Articles
Arrhythmia/Electrophysiology
  • Yoko Sato, Kentaro Yoshida, Kuniomi Ogata, Takeshi Inaba, Hiroshi Tada ...
    2012 Volume 76 Issue 7 Pages 1601-1608
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: April 03, 2012
    JOURNALS FREE ACCESS
    Background: Differences in electrical properties between left and right atria (LA and RA) after pulmonary vein isolation (PVI) for atrial fibrillation (AF) are currently poorly understood. Magnetocardiograms were used to investigate the effect of PVI on bi-atrial magnetic field changes and their relationship to clinical outcomes. Methods and Results: This study included 71 patients undergoing PVI for paroxysmal AF. Magnetocardiograms were recorded at baseline and 1 day, 8 weeks, and 24 weeks after ablation. Peak magnitude of LA and RA segments on P waves was separately compared before and after PVI. During a 16-month post-ablation period, 53 (75%) patients were free from AF recurrences. LA magnetic strength in patients without recurrence persistently decreased for 24 weeks and was significantly lower at 8 weeks than that in patients with recurrence (1.28±0.69 vs. 1.74±0.71 pico-Tesla, P=0.02). RA magnetic strength in patients with recurrence persistently rose for 24 weeks and was significantly higher at 8 weeks than that in patients without recurrence (2.17±0.82 vs. 3.00±1.12 pico-Tesla, P=0.001). Multivariate analysis showed RA magnetic strength at 8 weeks to be the strongest predictor of AF recurrence (odds ratio=3.335; 95% confidence interval=1.181-9.416; P=0.02). Conclusions: PVI resulted in distinct changes in magnetic strength in both the LA and the RA. A persistent rise in RA magnetic strength might be a robust predictor of AF recurrence after ablation.  (Circ J 2012; 76: 1601–1608)
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Cardiovascular Intervention
  • Hideki Ishii, Takanobu Toriyama, Toru Aoyama, Hiroshi Takahashi, Miho ...
    2012 Volume 76 Issue 7 Pages 1609-1615
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: April 07, 2012
    JOURNALS FREE ACCESS
    Background: Percutaneous coronary intervention (PCI) with drug-eluting stent (DES) is widely performed in patients with coronary artery disease, but the high restenosis rate remains a major clinical problem after implantation of DES in patients on hemodialysis (HD). Until now, there are limited reports regarding the long-term clinical outcome after implantation of DES in this patient population. Methods and Results: We compared bare metal stent (BMS) and DES for long-term clinical outcomes, such as target lesion revascularization (TLR), in HD patients undergoing PCI. BMS and DES were implanted in 204 and 301 patients, respectively. Baseline and lesion characteristics were comparable between the 2 groups. By Kaplan-Meier analysis, event rates of major adverse cardiac events for 6 years were significantly lower in the DES group than in the BMS group (42.5% vs. 58.0%, P=0.036). Although there were no significant differences in TLR rates between patients treated with DES and those with BMS at 1 year after PCI (17.8% vs. 21.3%, P=0.32), patients treated with DES had significantly lower rates of TLR compared with those treated with BMS beyond the 1-year follow-up after PCI (16.4% vs. 30.9%, P=0.019). Conclusions: In patients on HD, implantation of DES might be more effective for preventing TLR in the medium to long follow-up period than BMS, although restenosis after PCI with DES is common in the short term.  (Circ J 2012; 76: 1609–1615)
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  • Salvatore Brugaletta, Bill D. Gogas, Hector M. Garcia-Garcia, Vasim Fa ...
    2012 Volume 76 Issue 7 Pages 1616-1623
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: April 24, 2012
    JOURNALS FREE ACCESS
    Background: Implantation of a metallic prosthesis creates local stiffness with a subsequent mismatch in the compliance of the vessel wall, disturbances in flow and heterogeneous distribution of wall shear stress. Polymeric bioresorbable ABSORB scaffolds have less stiffness than metallic platform stents. We sought to analyze the mismatch in vascular compliance after ABSORB implantation and its long-term resolution with bioresorption. Methods and Results: A total of 83 patients from the ABSORB trials underwent palpography investigations (30 and 53 patients from ABSORB Cohorts A and B, respectively) to measure the compliance of the scaffolded and adjacent segments at various time points (from pre-implantation up to 24 months). The mean of the maximum strain values was calculated per segment by utilizing the Rotterdam Classification (ROC) score and expressed as ROC/mm. Scaffold implantation lead to a significant decrease in vascular compliance (median [IQR]) at the scaffolded segment (from 0.37 [0.24-0.45] to 0.14 [0.09-0.23], P<0.001) with mismatch in compliance in a paired analysis between the scaffolded and adjacent segments (proximal: 0.23 [0.12-0.34], scaffold: 0.12 [0.07-0.19], distal: 0.15 [0.05-0.26], P=0.042). This reported compliance mismatch disappears at short- and mid-term follow-up. Conclusions: The ABSORB scaffold decreases vascular compliance at the site of scaffold implantation. A compliance mismatch is evident immediately post-implantation and in contrast to metallic stents disappears in the mid-term, likely leading to a normalization of the rheological behavior of the scaffolded segment.  (Circ J 2012; 76: 1616–1623)
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  • Jin-Wook Chung, Keun-Ho Park, Min-Ho Lee, Kyung-Woo Park, Jin-Shik Par ...
    2012 Volume 76 Issue 7 Pages 1624-1630
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: April 14, 2012
    JOURNALS FREE ACCESS
    Supplementary material
    Background: The benefit of complete (CR) vs. incomplete revascularization (IR) with drug-eluting stent (DES), unlike with bypass grafting, is not well established in patients with multivessel coronary artery disease (MVD). Methods and Results: Consecutive patients from a single center DES registry who were newly diagnosed as having MVD and who underwent successful percutaneous coronary intervention between March 2003 and December 2009 were traced for the occurrence of death, myocardial infarction (MI), and repeat revascularization. Among 845 patients (337 with CR and 508 with IR), propensity score-matched 275 pairs were followed for a median of 3.9 years. The adjusted hazard ratio (HR) of CR [95% confidence interval] was 0.66 [0.34-1.28] for death; 0.51 [0.28-0.95] for death and MI; 0.84 [0.60-1.19] for death, MI, and repeat revascularization. The observed benefit of CR was also cardiac-specific. The adjusted HR of CR for cardiac death and MI was 0.39 [0.16-0.96]. In 3 subgroups of patients with diabetes (n=191), ejection fraction <55% (n=153) and estimated glomerular filtration rate (eGFR) <60ml/min (n=170), the benefit of CR was pronounced with the adjusted HR for cardiac death and MI of 0.27 [0.08-0.93], 0.18 [0.05-0.68] and 0.27 [0.07-0.99], respectively. Conclusions: In MVD patients treated with DES, CR was associated with the long-term benefit in reducing any or cardiac death and MI. The main beneficiaries of CR were those with diabetes, low ejection fraction and low eGFR.  (Circ J 2012; 76: 1624–1630)
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Cardiovascular Surgery
  • – Significance of INTERMACS Level and Renal Function –
    Daisuke Yoshioka, Taichi Sakaguchi, Shunsuke Saito, Shigeru Miyagawa, ...
    2012 Volume 76 Issue 7 Pages 1631-1638
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: April 07, 2012
    JOURNALS FREE ACCESS
    Background: The preoperative risk factors for left ventricular assist device (LVAD) implantation and their impact on the clinical outcome was analyzed to evaluate the optimal timing of LVAD implantation for severe heart failure patients. Methods and Results: From January 2006 to August 2011, 82 patients underwent 84 LVAD implantations at the Osaka University Hospital. These patients were categorized into 2 groups: Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) level 1 (n=41) and INTERMACS level 2/3 (n=43). The preoperative characteristics, early mortality, and cumulative survival between the 2 groups was compared. Ten (24.4%) patients died within 90 days in the INTERMACS level 1 group (multiple organ failure: 6, cerebrovascular event: 3, sepsis: 1), whereas 1 (2.3%) patient died because of a cerebrovascular event in the INTERMACS level 2/3 group (P=0.003). The cumulative survival rate was 82.9% at 30 days, 75.6% at 90 days, and 63.7% after 1 year in the INTERMACS level 1 group, and 100%, 97.7%, and 85.3% in the level 2/3 group (P=0.015). Using multivariate analysis for the INTERMACS level 1 group data, the preoperative serum creatinine level was the independent predictor of 90-day mortality. Conclusions: LVAD implantation in a stable condition contributes to better clinical outcome for severe heart failure patients. If critical cardiogenic shock occurs, LVAD implantation must be considered immediately before other organs' functions, especially renal function, deteriorate.  (Circ J 2012; 76: 1631–1638)
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Critical Care
  • Yasuyuki Hayashi, Taku Iwami, Tetsuhisa Kitamura, Tatsuya Nishiuchi, K ...
    2012 Volume 76 Issue 7 Pages 1639-1645
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: April 05, 2012
    JOURNALS FREE ACCESS
    Background: The effectiveness of epinephrine administration for cardiac arrests has been shown in animal models, but the clinical effect is still controversial. Methods and Results: A prospective, population-based, observational study in Osaka involved consecutive out-of-hospital cardiac arrest (OHCA) patients from January 2007 through December 2009. We evaluated the outcomes among adult non-traumatic bystander-witnessed OHCA patients for whom the local protocol directed the emergency medical service personnel to administer epinephrine. After stratifying by first documented cardiac rhythm, outcomes were compared among the following groups: non-administration, ≤10, 11-20 and ≥21min as the time from emergency call to epinephrine administration. A total of 3,161 patients were eligible for our analyses, among whom 1,013 (32.0%) actually received epinephrine. The epinephrine group had a significantly lower rate of neurologically intact 1-month survival than the non-epinephrine group (4.1% vs. 6.1%, P=0.028). In cases of ventricular fibrillation (VF) arrest, patients in the early epinephrine group who received epinephrine administration within 10min had a significantly higher rate of neurologically intact 1-month survival compared with the non-epinephrine group (66.7% vs. 24.9%), though other epinephrine groups did not. In cases of non-VF arrest, the rate of neurologically intact 1-month survival was low, irrespective of epinephrine administration. Conclusions: The effectiveness of epinephrine after OHCA depends on the time of administration. When epinephrine is administered in the early phase, there is an improvement in neurological outcome from OHCA with VF.  (Circ J 2012; 76: 1639–1645)
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Heart Failure
  • Shigeki Kobayashi, Takehisa Susa, Takeo Tanaka, Wakako Murakami, Seiko ...
    2012 Volume 76 Issue 7 Pages 1646-1653
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: April 05, 2012
    JOURNALS FREE ACCESS
    Background: The purpose of this study was to determine whether a low-dose β-blocker, in combination with milrinone, improves cardiac function in acute decompensated heart failure (ADHF) with tachycardia. Methods and Results: Twenty ADHF patients (New York Heart Association classification III, n=1, and IV, n=19; heart rate [HR], 107±12beats/min; left ventricular ejection fraction, 24±7%; cardiac index [CI], 2.2±0.6L·min-1·m-2; pulmonary capillary wedge pressure [PCWP], 26±8mmHg) were enrolled in this study. The patients first underwent conventional therapy with milrinone, vasodilators and diuretics; landiolol (1.5-6.0μg·kg-1·min-1; i.v.), which is an ultra-short-acting β1-selective blocker, was then added to the treatment regimen to study its effect on hemodynamics. Low-dose landiolol (1.5μg·kg-1·min-1) significantly reduced HR by 11% without changing blood pressure (BP) and CI, whereas higher doses (≥3.0μg·kg-1·min-1) tended to decrease BP and CI while increasing PCWP and systemic vascular resistance. After treatment with landiolol (1.5μg·kg-1·min-1), hemodynamic parameters such as PCWP, stroke volume index, SvO2, rate pressure product, filling time/RR, E/e', and Tei index were significantly improved. Conclusions: A low-dose β-blocker in combination with milrinone improved cardiac function in ADHF patients with tachycardia; therefore, it may be considered as an adjunct therapy for use when standard therapy with milrinone is not effective at slowing HR.  (Circ J 2012; 76: 1646–1653)
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  • Sumio Yamada, Yuko Shimizu, Makoto Suzuki, Tohru Izumi, Writing group ...
    2012 Volume 76 Issue 7 Pages 1654-1661
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: April 07, 2012
    JOURNALS FREE ACCESS
    Background: Although functional limitations (FLs) can predict clinical deterioration in chronic heart failure (CHF), few studies have focused on the associated clinical significance. The aim of the present study was to examine the association between FL and changes in the related time course with subsequent hospital readmission in CHF patients. Methods and Results: FLs were analyzed using the Performance Measure for Activities of Daily Living-8 (PMADL-8; higher scores indicate worse FLs) for 215 CHF patients at 1 and 3 months after discharge in a multicenter cohort study. The mean follow-up was 20 months. In a multivariate Cox regression analysis including covariates, only the PMADL-8 score remained significantly related to rehospitalization of CHF (hazard ratio, 2.49; 95% confidence interval: 1.27-4.90; P<0.01). Event-free survival differed significantly among the 4 PMADL-8 time-course groups (P<0.01). The persistent low-FL group had lower event rates than the other 3 time-course groups (P<0.01). Conclusions: FLs as measured by the PMADL-8 and the time course of the PMADL-8 score predict readmission in CHF patients after discharge. Accordingly, FL assessment is recommended as part of the clinical management because it not only identifies decline in physical function but also guides prognosis in CHF patients.  (Circ J 2012; 76: 1654–1661)
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  • – Report From the Registry of Hospitalized Heart Failure Patients –
    Sanae Hamaguchi, Shintaro Kinugawa, Mochamad Ali Sobirin, Daisuke Goto ...
    2012 Volume 76 Issue 7 Pages 1662-1669
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: April 06, 2012
    JOURNALS FREE ACCESS
    Background: The mode of death has not been investigated in the registry data of patients with heart failure and reduced ejection fraction (HFREF) vs. preserved ejection fraction (HFPEF). The aim of the present study was therefore to carry out this comparison. Methods and Results: The Japanese Cardiac Registry of Heart Failure in Cardiology (JCARE-CARD) prospectively studied the characteristics and treatments in a broad sample of 2,675 patients hospitalized with worsening HF, and followed them for an average of 2.1 years. This study included 323 patients in whom information on both the mode of death and left ventricular EF on echocardiography could be obtained. The mode of death was cardiovascular (CV) in 63% (including 17% sudden, 36% HF, 3% myocardial infarction, and 3% stroke), non-CV in 23%, and unknown in 14%. The prevalence of CV death including sudden death was high in patients with HFREF compared to HFPEF (68% vs. 58%, P=0.020). HF death, the most common mode of death, was similar between groups (37% vs. 35%, P=0.694). In contrast, non-CV mortality was significantly higher in HFPEF than those with HFREF (28% vs. 18%, P=0.021). Conclusions: In 60-70% of deaths the mode was CV, and HF death was the most common mode of death in either HFREF or HFPEF. The prevalence of sudden death was lower, and that of non-CV death higher, in HFPEF compared with HFREF.  (Circ J 2012; 76: 1662–1669)
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Hypertension and Circulatory Control
  • – Ambulatory Blood Pressure Monitoring –
    Hiroyuki Kayano, Shinji Koba, Taiju Matsui, Hiroto Fukuoka, Tsutomu To ...
    2012 Volume 76 Issue 7 Pages 1670-1677
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: April 06, 2012
    JOURNALS FREE ACCESS
    Background: Nocturnal and early morning hypertension are both significant risk factors for cardiovascular events. It remains unclear whether anxiety disorder affects nocturnal blood pressure (BP), early morning BP, or BP pattern in hypertensive patients. Methods and Results: One hundred and twenty consecutive hypertensive outpatients (77 men and 43 women; mean age, 66±11 years) were divided into 2 groups based on Hospital Anxiety and Depression Scale (HADS) score: a control group (n=78; HADS ≤10) and an anxiety group (42 patients; HADS ≥11). Nocturnal BP, early morning BP, morning BP surge (defined as BP rise ≥50mmHg), and BP pattern (extreme-dipper/dipper/non-dipper/riser) were measured on ambulatory BP monitoring. Clinical characteristics and BP were also evaluated at physician check-up. There was no significant difference between the 2 groups for BP check-up, but nocturnal and early morning BP were significantly higher in the anxiety group (142±16mmHg and 152±21mmHg) than in the control group (126±14mmHg and 141±18mmHg). With regard to patients with morning BP surge, nocturnal and early morning BP were also significantly higher in the anxiety group. The relative risk of existing anxiety disorders in riser-type hypertension was 4.48-fold higher (95% confidence interval: 1.58-12.74; P<0.005) than in dipper-type hypertension. Conclusions: Anxiety disorder is associated with nocturnal and early morning hypertension, and may be a risk factor for cardiovascular events.  (Circ J 2012; 76: 1670–1677)
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Imaging
  • Masaya Ohota, Masanori Kawasaki, Tevfik F. Ismail, Kousuke Hattori, Pa ...
    2012 Volume 76 Issue 7 Pages 1678-1686
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: April 18, 2012
    JOURNALS FREE ACCESS
    Background: While the utilization of integrated backscatter intravascular ultrasound (IB-IVUS) for the quantitative in vivo assessment of coronary plaque continues to grow, the validity of IB-IVUS images obtained from newly developed and conventional systems remains uncertain. Methods and Results: To assess the accuracy and reliability of a newly developed IB-IVUS system (VISIWAVE) as compared to the conventional system (Clearview), we compared quantitative IB-IVUS plaque characteristics in the 2 systems using 125 post-mortem specimens from 26 coronary arteries in 11 cadavers, as well as using 200 clinical plaques in 32 patients undergoing coronary intervention. The overall agreement between the histological and IB-IVUS diagnoses using VISIWAVE (Cohen's κ=0.82, 95%CI: 0.73-0.90) was similar to that using Clearview (Cohen's κ=0.80, 95%CI: 0.71-0.89). The 2 systems also demonstrated comparably high sensitivity and specificity. In the direct comparison, the overall agreement between IB-IVUS diagnoses using VISIWAVE and Clearview was also excellent (Cohen's κ=0.87, 95%CI: 0.78-0.95). In the clinical comparison, measured plaque dimensions were similar (VISIWAVE: 8.27±3.46mm2 vs. Clearview; 8.31±3.46mm2, P=0.44) and there was strong concordance between both greyscale and IB-IVUS parameters. Conclusions: There was close agreement of analyzed results in both systems when compared with the gold standard of histology. Both systems are able to reliably and accurately characterize coronary plaque and thereby make a valuable contribution to our understanding of atherosclerosis.  (Circ J 2012; 76: 1678–1686)
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Ischemic Heart Disease
  • Eiji Kunita, Hideya Yamamoto, Toshiro Kitagawa, Norihiko Ohashi, Hirot ...
    2012 Volume 76 Issue 7 Pages 1687-1696
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: April 10, 2012
    JOURNALS FREE ACCESS
    Supplementary material
    Background: Our group has previously reported that visceral adipose tissue (VAT) accumulation was associated with the extent and vulnerable characteristics of coronary plaques using coronary computed tomography angiography (CTA). An investigation of the associations between these coronary lesions with plasma adiponectin and leptin was performed. Methods and Results: A total of 394 patients (220 men and 174 women) in the study were referred for CTA. Plain abdominal scanning was simultaneously performed to evaluate VAT areas. The median level of plasma high-molecular-weight (HMW) adiponectin in patients with CTA-based obstructive coronary artery disease was significantly lower than that in patients without (men: 1.45 vs. 1.88μg/ml, P=0.002; women: 2.49 vs. 3.44μg/ml, P<0.001). Multivariate analyses revealed that a lower HMW adiponectin concentration was significantly associated with the presence (men: P=0.019; women: P=0.018) and involved segment numbers (men: P=0.001; women: P=0.003) of coronary plaques. Furthermore, it was significantly related to coronary plaque with all 3 vulnerable characteristics of positive remodeling, low CT density (≤38 Hounsfield units), and adjacent spotty calcium (men: P=0.019; women: P=0.016). These associations were also observed with VAT areas, but not with plasma leptin concentrations, in both genders. Conclusions: Lower plasma HMW adiponectin is associated with the presence, extent, and vulnerable characteristics of coronary plaques assessed by CTA in both genders.  (Circ J 2012; 76: 1687–1696)
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Molecular Cardiology
  • Chisato Takamura, Hirokazu Ohhigashi, Yusuke Ebana, Mitsuaki Isobe
    2012 Volume 76 Issue 7 Pages 1697-1702
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: May 16, 2012
    JOURNALS FREE ACCESS
    Background: The association of human leukocyte antigen (HLA) alleles and Takayasu arteritis (TA) is not fully understood. The aim of the present study was to investigate HLA alleles in Japanese patients with TA and the association of these alleles with clinical manifestations. Methods and Results: A total of 96 patients diagnosed with TA according to the Guideline for Management of Vasculitis Syndrome (Japanese Circulation Society 2008) and 371 healthy controls were enrolled in the present study. HLA genotyping showed a significant association of HLA-B67 (P=0.00024, odds ratio [OR]=4.94), a novel locus, and B52 (P<0.0001; OR=3.35), a conventional locus, with TA using both sequence-based typing and PCR-SSP assay. The frequency of HLA-B39, an allele reportedly associated with TA in Asian populations, was not higher than controls in the present study (P=0.86, OR=1.07). B52 had higher prevalence than B67 but the OR was higher for B67. We next studied the association of HLA-B67 and -B52 with clinical characteristics: age at disease onset, distribution of arteritis, pulmonary involvement, aortic regurgitation, systemic hypertension, steroid resistance and recurrence rate in TA. There was no significant difference in these clinical parameters between HLA-B67-positive or HLA-B52-positive patients and other patients. Conclusions: The HLA-B67 allele could be a new and important marker of TA because of its high OR compared to HLA-B52, although its prevalence in TA is lower.  (Circ J 2012; 76: 1697–1702)
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Pediatric Cardiology and Adult Congenital Heart Disease
  • Kazuki Kodo, Tsutomu Nishizawa, Michiko Furutani, Shoichi Arai, Kazuak ...
    2012 Volume 76 Issue 7 Pages 1703-1711
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: April 13, 2012
    JOURNALS FREE ACCESS
    Supplementary material
    Background: The genetic basis of most congenital heart defects (CHDs), especially non-syndromic and non-familial conditions, remains largely unknown. Methods and Results: DNA samples were collected from immortalized cell lines and original genomes of 256 non-syndromic, non-familial patients with cardiac outflow tract (OFT) defects. Genes encoding NKX2.5, GATA4, GATA6, MEF2C, and ISL1, essential for heart development, were analyzed using PCR-based bidirectional sequencing. The transcriptional activity of proteins with identified sequence variations was analyzed using a luciferase assay. A novel sequence variant (A103V in MEF2C) was identified, in addition to 4 unreported non-synonymous sequence variants in 3 known causative genes (A6V in NKX2.5, T330R and S339R in GATA4, and E142K in GATA6) in 5 individuals. None of these was found in 500 controls without CHDs. In vitro functional assay showed that all proteins with identified sequence variations exhibited significant changes in transcriptional activity and/or synergistic activity with other transcription factors. Furthermore, overexpression of the A103V MEF2C variant in a fish system disturbed early cardiac development. Conclusions: New mutations in the transcription factors NKX2.5, GATA4, GATA6, and MEF2C that affect their protein function were identified in 2.3% (6/256) of patients with OFT defects. Our results provide the first demonstration of MEF2C mutation and suggest that disturbances in the regulatory circuits involving these cardiac transcription factors may cause a subset of non-syndromic and non-familial CHDs.  (Circ J 2012; 76: 1703–1711)
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Peripheral Vascular Disease
  • Takahiro Miyauchi, Masaaki Miyata, Yoshiyuki Ikeda, Yuichi Akasaki, Na ...
    2012 Volume 76 Issue 7 Pages 1712-1721
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: April 06, 2012
    JOURNALS FREE ACCESS
    Background: Thermal therapy, namely Waon therapy, has previously been reported to regulate nitric oxide (NO) and endothelial NO synthase (eNOS) and augment ischemia-induced angiogenesis in mice and improve limb ischemia in patients with peripheral artery disease. The aim of this study was to clarify the precise mechanism by which Waon therapy augments angiogenesis in mice with hindlimb ischemia. Methods and Results: Unilateral hindlimb ischemia was induced in apolipoprotein E-deficient mice and Waon therapy was performed for 5 weeks. Heat shock protein 90 (Hsp90), phosphorylated-Akt, and phosphorylated-eNOS were detected in arterial endothelial cells of ischemic hindlimbs and all were upregulated by Waon therapy compared to controls. Waon therapy also increased serum concentrations of nitrite and nitrate. Capillary density and the ischemic limb/normal side blood perfusion ratio monitored by laser Doppler perfusion imaging in the Waon therapy group were significantly increased beyond those in the control group. The effect of Waon therapy on angiogenesis through the activation of the Hsp90/Akt/eNOS pathway was attenuated by the administration of a Hsp90 inhibitor. Conclusions: It is suggested that Waon therapy upregulates Hsp90, which contributes to the activation of the Akt/eNOS/NO pathway, and induces angiogenesis in mice with hindlimb ischemia.  (Circ J 2012; 76: 1712–1721)
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  • Daizo Kawasaki, Kenichi Fujii, Masashi Fukunaga, Motomaru Masutani, Ay ...
    2012 Volume 76 Issue 7 Pages 1722-1728
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: April 14, 2012
    JOURNALS FREE ACCESS
    Background: Carbon dioxide (CO2) has been used as an arterial contrast agent for high-risk patients who were allergic to iodinated contrast material and for those with chronic kidney disease (CKD). The feasibility, safety, imaging quality and therapeutic role of CO2 angiography in the endovascular therapy (EVT) for patients with CKD was evaluated. Methods and Results: EVT was performed in 107 consecutive patients with iliofemoral artery disease (148 limbs; mean age, 73±9 years) who were admitted to our hospital from January 2010 to April 2011. Intravascular ultrasound (IVUS)-guided EVT with CO2 was applied for the treatment of 50 patients (70 limbs) with CKD (group 1). IVUS-guided EVT with iodinated contrast media was applied for the treatment of 57 patients (78 limbs) without CKD (group 2). CO2 was injected by hand using a simple homemade delivery system. The overall technical success was 100% in both groups without any major complication. Preprocedure and postprocedure ankle-brachial indices significantly improved in the both groups (0.93±0.11 vs. 0.59±0.19, P<0.01; 0.95±0.13 vs. 0.62±0.22, P<0.01, respectively). All of the CO2 arteriograms were good or acceptable imaging quality if assessed by 2 independent observers. Conclusions: CO2 arteriograms, using an inexpensive simple homemade delivery system, are feasible and safe in patients with CKD in the evaluation and for EVT of iliofemoral artery disease.  (Circ J 2012; 76: 1722–1728)
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Pulmonary Circulation
  • Aiko Ogawa, Katsumasa Miyaji, Ichiro Yamadori, Yoko Shinno, Aya Miura, ...
    2012 Volume 76 Issue 7 Pages 1729-1736
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: April 05, 2012
    JOURNALS FREE ACCESS
    Background: Pulmonary veno-occlusive disease (PVOD) and pulmonary capillary hemangiomatosis (PCH) are rare causes of pulmonary hypertension. There is no proven medical therapy to treat these diseases, and lung transplantation is thought to be the only cure. Administration of vasodilators including epoprostenol sometimes causes massive pulmonary edema and could be fatal in these patients. Methods and Results: Eight patients were treated with epoprostenol for 387.3±116.3 days (range, 102-1,063 days), who were finally diagnosed with PVOD or PCH by pathological examination. The maximum dose of epoprostenol given was 55.3±10.7ng·kg-1·min-1 (range, 21.0-110.5ng·kg-1·min-1). With careful management, epoprostenol therapy significantly improved the 6-min walk distance (97.5±39.2 to 329.4±34.6m, P<0.001) and plasma brain natriuretic peptide levels (381.3±136.8 to 55.2±14.4pg/ml, P<0.05). The cardiac index significantly increased from 2.1±0.1 to 2.9±0.3L·min-1·m-2 (P<0.05). However, pulmonary artery pressure and pulmonary vascular resistance were not significantly reduced. For 4 patients, epoprostenol therapy acted as a bridge to lung transplantation. For the other patients who had no chance to undergo lung transplantation, epoprostenol therapy was applied for 528.0±216.6 days and the maximum dose was 63.9±19.0ng·kg-1·min-1. Conclusions: This study data suggest that cautious application of epoprostenol can be considered as a therapeutic option in patients with PVOD and PCH.  (Circ J 2012; 76: 1729–1736)
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  • Yoshitake Yamada, Shigeo Okuda, Masaharu Kataoka, Akihiro Tanimoto, Yu ...
    2012 Volume 76 Issue 7 Pages 1737-1743
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: April 12, 2012
    JOURNALS FREE ACCESS
    Supplementary material
    Background: Because few have reported the prognostic significance of cardiac magnetic resonance imaging (CMR) for idiopathic pulmonary arterial hypertension (IPAH), in this study we evaluated the value of CMR measurements as a prognostic predictor of IPAH before starting intravenous prostacyclin therapy. Methods and Results: A total of 121 consecutive CMR studies for evaluating right ventricular (RV) function were reviewed. Forty-one patients were diagnosed with IPAH and served as the study group. Factors, such as age, sex, New York Heart Association functional class (NYHAFC), 6-min walk test, plasma brain natriuretic peptide level, serum uric acid level and CMR measurements were analyzed as predictors of first hospitalization and death. The mean follow-up period was 1,350±769 days. Nine patients were hospitalized because of heart failure, and 4 patients died from cardiopulmonary causes. The univariate analyses suggested that the left ventricular (LV) mass index, the left and right ventricular end-diastolic volume indices (LVEDVI, RVEDVI), the LV and RV end-systolic volume indices (LVESVI, RVESVI) and NYHAFC predicted the risk for hospitalization and that RVEDVI, RVESVI and NYHAFC predicted mortality. The multivariate analyses suggested that RVEDVI and NYHAFC are independent predictors of both hospitalization and mortality. The effects of RVEDVI and NYHAFC on hospitalization were not substantially affected by the concomitant medication. Conclusions: In IPAH patients, the RVEDVI predicts both hospitalization for right heart failure and mortality before initiating intravenous prostacyclin therapy.  (Circ J 2012; 76: 1737–1743)
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  • Grzegorz Kopec, Anna Tyrka, Tomasz Miszalski-Jamka, Maciej Sobien, Mar ...
    2012 Volume 76 Issue 7 Pages 1744-1749
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: April 13, 2012
    JOURNALS FREE ACCESS
    Background: Currently, there are no data on the association between right ventricular (RV) structure and ECG changes specific for idiopathic pulmonary arterial hypertension (IPAH). Therefore, we aimed to assess the accuracy of the recommended ECG criteria for predicting RV hypertrophy (RVH) and dilation in patients with IPAH. Methods and Results: Twelve-lead ECG and cardiovascular magnetic resonance imaging (CMR) were performed in 23 consecutive patients with IPAH aged 49.8±16.3 years. ECG criteria were referred to RV mass index and RV end-diastolic volume index as measured by CMR. Only the ECG voltage criteria based on R wave amplitude in lead V1, R wave amplitude in aVR, P wave amplitude in II and ventricular activation time in V1 were useful for differentiating between patients with and without RVH. A ventricular activation time in lead V1 of <0.01s excluded RVH, whereas R in V1 >6mm, R:S in V1 >1, R in aVR >4mm, R:S in V5 to R:S in V1 <0.04 and P in II >2.5mm confirmed the diagnosis. Only the ventricular activation time in V1 correlated with RV dilation and when >0.045s confirmed its diagnosis. Conclusions: Only a few of the recommended ECG criteria proved to be useful in the diagnosis of RVH or RV dilation in patients with IPAH. Changes in the cut-off values improved their accuracy.  (Circ J 2012; 76: 1744–1749)
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Regenerative Medicine
  • – A Pilot Study –
    Han Cheol Lee, Sung Gyu An, Hye Won Lee, Jin-Sup Park, Kwang Soo Cha, ...
    2012 Volume 76 Issue 7 Pages 1750-1760
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: April 12, 2012
    JOURNALS FREE ACCESS
    Background: Treatment of critical limb ischemia (CLI) by bypass operation or percutaneous vascular intervention is occasionally difficult. The safety and efficacy of multiple intramuscular adipose tissue-derived mesenchymal stem cells (ATMSC) injections in CLI patients was determined in the study. Methods and Results: The study included 15 male CLI patients with ischemic resting pain in 1 limb with/without non-healing ulcers and necrotic foot. ATMSC were isolated from adipose tissue of thromboangiitis obliterans (TAO) patients (B-ATMSC), diabetes patients (D-ATMSC), and healthy donors (control ATMSC). In a colony-forming unit assay, the stromal vascular fraction of TAO and diabetic patients yielded lesser colonies than that of healthy donors. D-ATMSC showed lower proliferation abilitythan B-ATMSC and control ATMSC, but they showed similar angiogenic factor expression with control ATMSC and B-ATMSC. Multiple intramuscular ATMSC injections cause no complications during the follow-up period (mean follow-up time: 6 months). Clinical improvement occurred in 66.7% of patients. Five patients required minor amputation during follow-up, and all amputation sites healed completely. At 6 months, significant improvement was noted on pain rating scales and in claudication walking distance. Digital subtraction angiography before and 6 months after ATMSC implantation showed formation of numerous vascular collateral networks across affected arteries. Conclusions: Multiple intramuscular ATMSC injections might be a safe alternative to achieve therapeutic angiogenesis in patients with CLI who are refractory to other treatment modalities.  (Circ J 2012; 76: 1750–1760)
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Valvular Heart Disease
  • Kentaro Shibayama, Hiroyuki Watanabe, Minoru Tabata, Shunsuke Sasaki, ...
    2012 Volume 76 Issue 7 Pages 1761-1767
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: April 03, 2012
    JOURNALS FREE ACCESS
    Background: Aortic stenosis (AS) is increasingly common in the elderly population. A recent invention of transcatheter aortic valve implantation tends to tilt the risk-benefit balance to favor earlier elective intervention for AS. Hence, decision making for elective intervention in octogenarians gradually becomes important. However, the outcome after elective aortic valve replacement (eAVR) has not been evaluated adequately. This study aimed to identify risk factors after eAVR in octogenarians and investigate their influence on long-term outcome. Methods and Results: One hundred and thirty-seven consecutive Japanese octogenarians with AS who underwent eAVR were studied. The mean follow-up period was 35±22 (range, 0-88) months. Long-term overall survival rates after eAVR were 92.0%, 85.2% and 75.5% at 1, 3 and 5 years, respectively. Cox proportional hazards model identified age [hazard ratio (HR) 1.23; 95% confidence interval (CI) 1.07-1.43; P<0.01)] and ejection fraction (EF) <50% (HR 3.38; 95%CI 1.34-8.52; P<0.01) as the risk factors of mortality. Post-eAVR survival rates in octogenarians with an EF ≥50% and <50% were 97.3% and 70.4% at 1 year, 90.1% and 65.3% at 3 years, and 84.3% and 39.2% at 5 years, respectively (P<0.0001). Conclusions: Octogenarians with preserved LV systolic function before surgery have favorable long-term survival after eAVR. However, an EF <50% influences the mortality in octogenarian patients. Therefore, eAVR should be considered for octogenarians with AS before the progression of LV impairment.  (Circ J 2012; 76: 1761–1767)
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Vascular Biology and Vascular Medicine
  • Junko Ohashi, Ayuko Sawada, Sota Nakajima, Kazuki Noda, Aya Takaki, Hi ...
    2012 Volume 76 Issue 7 Pages 1768-1779
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: March 30, 2012
    JOURNALS FREE ACCESS
    Supplementary material
    Background: Endothelium-derived relaxing factors play an important role in cardiovascular homeostasis. Among them, endothelium-derived hyperpolarizing factor (EDHF) is important especially in microcirculation. It has previously been demonstrated that endothelium-derived hydrogen peroxide (H2O2) is an EDHF in animals and humans and that endothelial nitric oxide synthase (eNOS) plays diverse roles as a nitric oxide (NO) generating system in conduit arteries and as an EDHF/H2O2 generating system in microvessels. As compared with NO-mediated responses, those by EDHF are resistant to atherosclerosis, contributing to the maintenance of cardiovascular homeostasis. The aim of this study is to elucidate the molecular mechanisms for enhanced EDHF-mediated responses in microvessels. Methods and Results: This study used male wild-type mice and caveolin-1-deficient mice (caveolin-1-/- mice). In the endothelium, eNOS was functionally suppressed in mesenteric arteries (microvessels) compared with the aorta (conduit arteries), for which Ca2+/calmodulin-dependent protein kinase kinase β (CaMKKβ) and caveolin-1 are involved, as EDHF-mediated responses were inhibited by STO-609 (an inhibitor of CaMKKβ) and in caveolin-1-/- mice, respectively. In vascular smooth muscle, relaxation responses to H2O2 were enhanced through a protein kinase G1α (PKG1α)-mediated mechanism in mesenteric arteries compared with the aorta, as they were inhibited by Rp-8-Br-cGMPS (an inhibitor of PKG1α). Conclusions: These results indicate that CaMKKβ, caveolin-1, and PKG1α are substantially involved in the mechanisms for the enhanced EDHF-mediated responses in microvessels in mice.  (Circ J 2012; 76: 1768–1779)
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  • Xiao-Hua Yu, Hai-Lu Jiang, Wu-Jun Chen, Kai Yin, Guo-Jun Zhao, Zhong-C ...
    2012 Volume 76 Issue 7 Pages 1780-1791
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: April 12, 2012
    JOURNALS FREE ACCESS
    Supplementary material
    Background: Interleukin (IL)-18 and IL-12 synergize for the production of interferon (IFN)-γ, which can downregulate ATP-binding cassette transporter A1 (ABCA1) expression. The aim of the present study was to investigate the effect of IL-18 and/or IL-12 on ABCA1 expression. Methods and Results: IL-18 combined with IL-12 decreased ABCA1 expression and cellular cholesterol efflux in THP-1 macrophage-derived foam cells, whereas IL-18 or IL-12 alone had no effect. IL-12 increased IL-18 receptor (IL-18R) expression, which was suppressed by small interfering RNA (siRNA) for signal transducer and activator of transcription 3. IL-18R but not IL-12 receptor siRNA completely reversed the effects of IL-18 and IL-12 on ABCA1 expression and cellular cholesterol efflux. Treatment with IL-18 plus IL-12 markedly augmented nuclear translocation of nuclear factor (NF)-κB but had no effect on expression and activity of liver X receptor α. IL-18 and IL-12 also significantly increased zinc finger protein 202 (ZNF202) levels and IFN-γ secretion. Furthermore, siRNA for ZNF202 or IFN-γ significantly impaired IL-18/IL-12-induced suppression of ABCA1, whereas NF-κB siRNA treatment blocked IL-18/IL-12' action on ZNF202 levels, IFN-γ secretion, and ABCA1 expression. Conclusions: IL-18 and IL-12 together can decrease ABCA1 expression and cellular cholesterol efflux in THP-1 macrophage-derived foam cells through the IL-18R/NF-κB signaling pathway.  (Circ J 2012; 76: 1780–1791)
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  • Dou Dou, Xiaoxu Zheng, Juan Liu, Xiaojian Xu, Liping Ye, Yuansheng Gao
    2012 Volume 76 Issue 7 Pages 1792-1798
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: April 11, 2012
    JOURNALS FREE ACCESS
    Background: cGMP-dependent protein kinase type I (PKG I) plays a key role in vasodilatation caused by cGMP-elevating agents. It is a homodimer in mammalian cells, existing as 2 isoforms, Iα and Iβ. The aim of the present study was both to determine whether PKG I dimerization and activity are modulated by hydrogen peroxide (H2O2) and its influence on vasodilatation. Methods and Results: The dimers and monomers of total PKG I and PKG Iβ were analyzed by Western blotting. PKG I activity was assayed by measuring the incorporation of 32P into BPDEtide. Changes in vessels tension were determined by organ chamber technique. In isolated porcine coronary arteries, H2O2 increased the dimers of total PKG I in a concentration-dependent manner, but had no effect on dimerization of PKG Iβ. The dimerization of PKG I caused by H2O2 was prevented by catalase but not by deferoxamine and tiron. H2O2 promoted the translocation of PKG I from cytoplasm to membrane. H2O2 enhanced the activity of PKG I and relaxations of porcine coronary arteries to the nitric oxide donor and 8-Br-cGMP. Inhibition of catalase under in vivo conditions significantly decreased rat mean arterial pressure, which was associated with increased dimerization of PKG I. Conclusions: The present study suggests that H2O2 may enhance the activity of PKG Iα-and PKG I-dependent vasodilatation via increased dimerization of the enzyme.  (Circ J 2012; 76: 1792–1798)
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Rapid Communication
  • – A Pilot Study Using a Human Heart Specimen –
    Minoru Yamada, Masahiro Jinzaki, Sachio Kuribayashi, Nobuaki Imanishi, ...
    2012 Volume 76 Issue 7 Pages 1799-1801
    Published: 2012
    Released: June 25, 2012
    [Advance publication] Released: May 18, 2012
    JOURNALS FREE ACCESS
    Background: Investigate the effectiveness of beam-hardening (BH) correction using ECG-gated dual-kVp computed tomography (CT) for myocardial imaging. Methods and Results: A human heart specimen and artificial descending aorta were scanned using both dual-kVp and single 120-kVp modes. The myocardial CT values at the anterior and posterobasal walls were 89.4±6.2 and 87.1±6.9HU (P=0.59) for the 69-keV images, and 88.3±5.9 and 49.9±13.5HU (P=0.002) for the 120-kVp images, respectively. Conclusions: Fast-switching dual-kVp technology is feasible for the correction of CT value deficits induced by BH that mimics perfusion defects.  (Circ J 2012; 76: 1799–1801)
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