Circulation Journal
Online ISSN : 1347-4820
Print ISSN : 1346-9843
ISSN-L : 1346-9843
Volume 69, Issue 3
Displaying 1-22 of 22 articles from this issue
Clinical Investigation
  • Findings From the Hawaii-Los Angeles-Hiroshima Study
    Tomoki Shokawa, Michinori Imazu, Hideya Yamamoto, Mamoru Toyofuku, Nao ...
    2005 Volume 69 Issue 3 Pages 259-264
    Published: 2005
    Released on J-STAGE: February 25, 2005
    JOURNAL FREE ACCESS
    Background Arterial stiffness measurements, generally from pulse wave velocity (PWV), are widely used with little knowledge of their relationship to long-term cardiovascular mortality in general populations. Methods and Results We studied a cohort of 492 Japanese-Americans living in Hawaii (mean age: 63.7 ±8.8 years) to assess the relationship between PWV and cardiovascular disease mortality and all-cause mortality. During the 10-year follow-up, 43 patients died (14 from cardiovascular events). The cohort was divided into 2 groups by the cut-off value of PWV (9.9 m/s) represented in the receiver operating characteristic curve. The risk ratio for PWV values >9.9 m/s to all-cause mortality was 1.28 [95% confidence interval (CI): 1.14-1.42], and adjusted for other risk factors this ratio was 1.42 (95% CI: 0.96-2.11). The corresponding risk ratios for cardiovascular mortality was 4.46 (95% CI: 1.61-12.32) and 4.24 (95% CI: 1.39-12.96), respectively. Conclusions The present study demonstrated that an increased PWV value is associated with future cardiovascular disease death in Japanese-Americans living in Hawaii. (Circ J 2005; 69: 259 - 264)
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  • Comparison of Therapeutic Regimens
    Zenshiro Onouchi, Kenji Hamaoka, Koichi Sakata, Seiichiro Ozawa, Isao ...
    2005 Volume 69 Issue 3 Pages 265-272
    Published: 2005
    Released on J-STAGE: February 25, 2005
    JOURNAL FREE ACCESS
    Background There are few studies of the therapeutic regimens for the prevention of stenotic transformation of aneurysms in Kawasaki disease (KD). The aim of this study was to assess the prophylactic effect of combined therapy in the acute stage and convalescent- to chronic-stage against the formation of stenotic lesions. Methods and Results In 85 patients, 103 giant aneurysms (ANl), 46 medium-sized aneurysms (ANm), and 13 small aneurysms (ANs) were analyzed. With respect to therapy in the acute stage, no localized stenosis of ANl in the left coronary artery was noted in patients who received high-dose gamma globulin therapy (G). For ANm, the group (G) showed a significantly higher regression rate than the aspirin group and steroids group. Furthermore, no coronary artery occlusion/recanalization of ANl occurred with the prophylactic regimen of aspirin and warfarin {aw}. Prophylaxis {aw} and the prophylactic regimen of aspirin alone {a} significantly lowered the incidence compared with either the prophylactic regimen of warfarin {w} or no prophylaxis {n}. However, no significant differences were noted between prophylaxis {w} and {n}. Conclusions High-dose gamma globulin therapy in the acute stage of KD is the first choice for the prevention of stenotic transformation. Prophylaxis {aw} is recommended for ANl. (Circ J 2005; 69: 265 - 272)
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  • Mari Iwamoto, Ichiroh Niimura, Toshimitsu Shibata, Kiyoshi Yasui, Kiyo ...
    2005 Volume 69 Issue 3 Pages 273-276
    Published: 2005
    Released on J-STAGE: February 25, 2005
    JOURNAL FREE ACCESS
    Background The prognosis of ventricular tachycardia (VT) in children with overt heart disease is generally good, so the aim of this study was to review the prognosis and necessity of treatment of VT that detected by school-based heart disease screening. Methods and Results Of the 48 cases of pediatric VT that have been followed for 2-30 years, 17% were diagnosed at the first school-based screening test (12-lead ECG at rest) and the remainder who had premature ventricular contractions (PVC) on the resting 12-lead ECG required Holter ECG test and exercise stress ECG test to detect VT. In 90% of cases, VT in healthy children is idiopathic non-sustained VT and more than half of the present cases showed natural disappearance of the VT during follow up. In particular, cases of monomorphic PVC or maximum PVC runs less than 5 had a good prognosis. The cases of polymorphic VT and VT with heart disease continued for the long term. Conclusion Treatment is unnecessary for monomorphic VT with the maximum number of salvos less than 5. The necessity for treatment depends on the symptoms and profile of the VT. The prognosis for polymorphic VT and underlying heart disease is not good and may require implantable cardioverter defibrillator. (Circ J 2005; 69: 273 - 276)
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  • Anomalous Behavior of Plasma BNP in Hypertrophic Cardiomyopathy
    Ichiro Takeuchi, Takayuki Inomata, Mototsugu Nishii, Toshimi Koitabash ...
    2005 Volume 69 Issue 3 Pages 277-282
    Published: 2005
    Released on J-STAGE: February 25, 2005
    JOURNAL FREE ACCESS
    Background Although it is not rare to encounter patients with plasma B-type natriuretic peptide (BNP) levels unequivalent to the severity of heart failure (HF), there has been little investigation to clarify the causative background of this phenomenon. Methods and Results Among the 1,838 outpatients whose plasma BNP was measured, persistently increased levels of BNP above 500 pg/ml was observed for more than 6 months in 14 subjects with few HF symptoms. Among these, all of 4 patients without any following cardiac events (E-/high) for 12 months showed hypertrophic nonobstructive cardiomyopathy (HNCM). When we compared the clinical parameters of these patients with those of 22 HNCM patients without any following cardiac events whose plasma BNP levels were less than 200 pg/ml, there were only 2 clinical characteristics to be distinguished: (i) plasma renin activity (PRA) and norepinephrine (NE) levels were low in spite of markedly increased levels of plasma BNP in E-/high HNCM; and (ii) echocardiographic investigation revealed that only global left atrial fractional shortening was significantly lower in E-/high HNCM. Conclusions Plasma BNP levels do not always reflect the severity of HF in HNCM. It might be considered to utilize other clinical parameters such as NE and PRA to recognize HF severity in such patients. (Circ J 2005; 69: 277 - 282)
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  • Mitsuru Suwa, Yoshihiko Seino, Yoshikata Nomachi, Shinsuke Matsuki, Ka ...
    2005 Volume 69 Issue 3 Pages 283-290
    Published: 2005
    Released on J-STAGE: February 25, 2005
    JOURNAL FREE ACCESS
    Background Efficacy and safety assessments for carperitide (α-human atrial natriuretic peptide) in previous clinical trials have not mentioned its limitations in practice as therapy for acute heart failure. Methods and Results A 6-year prospective open-label registry analysis was conducted in the `real world' of therapy for 3,777 patients with acute heart failure (male 57%, median age 73) treated with 0.085 μg · kg-1 · min-1 (median, interquartile 0.05-0.1) of carperitide for 65 h (median, interquartile 22-142); 51% were assessed as class III or IV according to the Killip classification; 82% of the patients were assessed as clinically improved after carperitide treatment. The efficacy limitation was related to the underlying disease (acute myocardial infarction), severity of Killip classification (Class IV), and renal function disturbance. The efficacy was significantly higher in patients with decompensated chronic heart failure (ie, cardiomyopathy, valvular diseases, and hypertensive heart disease). Incidence of adverse events was 16.9%, the most frequent being blood pressure lowering (9.5%), which occurred in the first 3 h of infusion, with 96% of patients recovering or improving without specific treatment. Logistic regression analysis revealed that factors predicting mortality (11.4%) during 7 days of follow-up were age, Killip classification, renal function disturbance, low blood pressure and use of vasopressors. Conclusion The clinical condition improved in 82% of patients treated with carperitide. Based on these findings, minute strategy will be established for carperitide therapy within the strata of patient characteristics that may predict the prognosis. (Circ J 2005; 69: 283 - 290)
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  • Kunihisa Miwa, Chiharu Kishimoto, Hajime Nakamura, Toshinori Makita, K ...
    2005 Volume 69 Issue 3 Pages 291-294
    Published: 2005
    Released on J-STAGE: February 25, 2005
    JOURNAL FREE ACCESS
    Background Oxidative stress, which is thought to be increased in subjects with various coronary risk factors, induces thioredoxin (TRX), a redox-active protein. Methods and Results To determine whether oxidative stress is increased, serum concentrations of both TRX and α-tocopherol (vitamin E) were determined in 12 control subjects without any coronary risk factors (CONTROL), 6 current smokers (SMOKING), 19 hypertensive patients (HT), 7 hypercholesterolemic patients (HC) and 14 subjects with multiple risk factors (MULTIPLE). Patients with diabetes mellitus were not included. The serum TRX concentrations (mean ± SD ng/ml) were significantly higher in SMOKING (41±10), HT (41±17), HC (48±15) and MULTIPLE (46±15) than in CONTROL (24±11). The serum α-tocopherol concentrations (mg/g lipids) were not significantly different among CONTROL (4.0±0.7), SMOKING (4.0±0.8), HT (4.1±0.6) and HC (4.2±0.6), although the concentration was significantly lower in MULTIPLE (3.3±0.7) than in any of the other study groups. Conclusions SMOKING, HT, HC and MULTIPLE had significantly higher serum TRX concentrations than CONTROL, suggesting increased oxidative stress. MULTIPLE had a lower serum concentration of antioxidant α-tocopherol than any of the other study groups, suggesting impaired or exhausted defense against chronic oxidative stress in the presence of the multiple risk factors. (Circ J 2005; 69: 291 - 294)
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  • Norihiko Shinozaki, Hiroyoshi Yokoi, Masashi Iwabuchi, Hideyuki Nosaka ...
    2005 Volume 69 Issue 3 Pages 295-300
    Published: 2005
    Released on J-STAGE: February 25, 2005
    JOURNAL FREE ACCESS
    Background The BiodivYsio stent is coated with a phosphorylcholine containing copolymer to confer biocompatibility. The present study was designed to assess the safety and efficacy of this coronary stent for the treatment of native coronary artery lesions in patients with coronary artery disease. Methods and Results From August 2001 to April 2003, 130 patients with lesions were treated with this stent. Elective stenting (ES) was performed in 90 patients and bailout stenting (BS) was performed in 40 patients with small vessels. Pre-interventional reference diameter, minimal lumen diameter (MLD), and lesion length were 2.68±0.51, 1.00±0.30, 12.78±4.32, respectively, and post-interventional MLD was 2.24±0.45 mm. The initial success rate was 100%. However, 2 non-Q-wave myocardial infarctions (non-QMI) occurred post-procedurally due to branch occlusion. A 6-month follow-up was performed. No subacute thrombosis occurred. In the ES group, 1 non-QMI occurred after the interventional procedure in another vessel. There was no death or coronary artery bypass grafting (CABG). The angiographic restenosis rate was 15.6%. In the BS group, there was no death, myocardial infarction or CABG. The angiographic restenosis rate was 17.5%. Conclusion The BiodivYsio stent is safe and effective as a primary device for the treatment of native coronary artery lesions, especially in small vessels. (Circ J 2005; 69: 295 - 300)
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  • Study by Separate Acquisition, Dual-Isotope ECG-Gated Single-Photon Emission Computed Tomography
    Shunichi Yoda, Yuichi Sato, Naoya Matsumoto, Shigemasa Tani, Tadateru ...
    2005 Volume 69 Issue 3 Pages 301-305
    Published: 2005
    Released on J-STAGE: February 25, 2005
    JOURNAL FREE ACCESS
    Background Although the detection of wall motion abnormalities gives incremental value to myocardial perfusion single-photon emission computed tomography (SPECT) in the diagnosis of extensive coronary artery disease (CAD) and high-grade single-vessel CAD, whether or not it is useful in the diagnosis of mild, single-vessel CAD has not been studied previously. Methods and Results Separate acquisition, dual isotope ECG-gated SPECT was performed in 97 patients with a low likelihood of CAD (Group 1) and 46 patients with single-vessel CAD (Group 2). Mild CAD was defined by stenosis of 50-75% (Group 2a, n=22) and moderate to severe CAD was defined by stenosis ≥76% (Group 2b, n=24). Myocardial perfusion and wall motion were graded by a 5 point-scale, 20-segment model. The sensitivity of myocardial perfusion alone was 50% for Group 2a, 83% for Group 2b and 67% for Group 2 as a whole. The overall specificity was 90%. When the wall motion analysis was combined, the sensitivity was increased to 82% in Group 2a and 92% in Group 2b. Conclusion The ability to detect a wall motion abnormality immediately after exercise gives incremental diagnostic value to myocardial perfusion SPECT in the identification of mild, single-vessel CAD. (Circ J 2005; 69: 301 - 305)
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  • Ju Han Kim, Myung Ho Jeong, Kyung Ho Yun, Kye Hun Kim, Dong Koo Kang, ...
    2005 Volume 69 Issue 3 Pages 306-310
    Published: 2005
    Released on J-STAGE: February 25, 2005
    JOURNAL FREE ACCESS
    Background The purpose of the study was to prospectively evaluate the protective effect of nicorandil during percutaneous coronary intervention (PCI) in patients with unstable angina (UAP). Methods and Results Two hundred patients (61±10 year-old, male 143) diagnosed with UAP at an emergency medical center were randomly assigned to 2 groups: intravenous isosorbide dinitrate, Group I (n=100), or intravenous nicorandil, Group II (n=100). PCI was performed 12-48 h after infusion of each agent. Serum concentrations of creatine kinase-MB (CK-MB), cardiac troponin T (cTnT), and I (cTnI) were measured before and 6, 12, 24 h after PCI. Patients with non-coronary chest pain, requiring emergency coronary angiogram, temporary pacemaker or glycoprotein IIb/IIIa receptor blocker were excluded. PCI was successfully performed in 96 patients (Group I=54, 61.7±8.2 years, 32 males; Group II=42, 60.4±11.7 years, 27 males). No significant differences in clinical or coronary angiographic characteristics were observed between the 2 groups. The concentration of CK-MB was elevated in 9 patients (17%) of Group I and 6 (14%) of Group II, cTnT in 16 (30%), 6 (14%) and cTnI in 25 (46%), 9 (21%) after PCI. Elevation of any troponin was less frequent in Group II [28/54 (52%) vs 10/42 (24%) patients, p=0.01]. Major adverse coronary events during the 6-month clinical follow-up occurred in 9 (17%) of Group I and 5 patients of Group II (12%, p=NS). Follow-up echocardiography revealed lower left ventricular ejection fraction in Group I than in Group II (65.4±7.2% vs 71.0±6.7%, p=0.03). Conclusion Nicorandil has a myocardial protective effect during PCI in patients with UAP. (Circ J 2005; 69: 306 - 310)
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  • A Study of Patients With Large Acute Myocardial Infarction and Receiving Revascularization Therapy
    Hidenori Seki, Takuji Toyama, Kyosuke Higuchi, Shu Kasama, Tetsuya Ued ...
    2005 Volume 69 Issue 3 Pages 311-319
    Published: 2005
    Released on J-STAGE: February 25, 2005
    JOURNAL FREE ACCESS
    Background 18F-fluorodeoxyglucose (FDG) positron-emission tomography (PET) is assumed to be the most useful method of evaluating the viability of the myocardium, but its use is limited by the need for a cyclotron. In the present study, the ability of a combination of 99mTc-tetrofosmin (TF) and 123I-β-methyliodophenyl pentadecanoic acid (BMIPP) single-photon emission computed tomography (SPECT), a combination of 18F-FDG PET and 123I-BMIPP SPECT, and a combination of 18F-FDG PET and 99mTc-TF SPECT were compared to predict functional improvement of ischemic myocardium after a large acute myocardial infarction (AMI). Methods and Results Ten patients with large AMI were studied by 99mTc-TF SPECT, 123I-BMIPP SPECT and 18F-FDG PET within 3 weeks. Six months later, 99mTc-TF imaging was performed. All patients underwent successful revascularization, and had no restenosis. Regional tracer uptake was scored using a 4-point scale in 20 segments of the SPECT and PET images. When the defect score of 123I-BMIPP SPECT exceeded the defect score of 99mTc-TF SPECT or 18F-FDG PET by 1 point or more, and when the defect score of 99mTc-TF SPECT exceeded the defect score of 18F-FDG PET by 1 point or more, the segment was considered to show mismatching. When the defect score was the same in 2 tracers, the segment was considered to show matching. 99mTc-TF imaging at 3 weeks and 6 months used quantitative gated SPECT (QGS) to score wall motion using a 6-point scale (-1= dyskinesis, 0= akinesis, 1= severe hypokinesis, 2= moderate hypokinesis, 3= mild hypokinesis, and 4= normokinesis). The sensitivity of the combination of 123I-BMIPP and 99mTc-TF imaging in predicting functional improvement was 61%, that of 18F-FDG PET and 123I-BMIPP SPECT was 94%, and that of 18F-FDG PET and 99mTc-TF SPECT was 76%. The specificity of the combination of 123I-BMIPP and 99mTc-TF imaging in predicting functional improvement was 83%, that of 18F-FDG PET and 123I-BMIPP SPECT was 40%, and that of 18F-FDG PET and 99mTc-TF SPECT was 49%. The accuracy of the combination of 123I-BMIPP and 99mTc-TF imaging in predicting functional improvement was 70%, that of 18F-FDG PET and 123I-BMIPP SPECT was 71%, and that of 18F-FDG PET and 99mTc-TF SPECT was 63%. Conclusion The combination of 123I-BMIPP and 99mTc-TF imaging is a practical modality for predicting the functional improvement of ischemic myocardium after a large AMI. (Circ J 2005; 69: 311 - 319)
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  • Yuichi Sato, Fumio Inoue, Naoya Matsumoto, Shigemasa Tani, Tadateru Ta ...
    2005 Volume 69 Issue 3 Pages 320-324
    Published: 2005
    Released on J-STAGE: February 25, 2005
    JOURNAL FREE ACCESS
    Background Anomalous origins of the coronary artery are rare, but may cause myocardial ischemia and sudden death. Thus, their reliable identification is crucial for any imaging method that attempts coronary artery visualization and of those available multislice computed tomography (MSCT), which provides excellent spatial resolution, may be the most promising. Methods and Results In consecutive 1,153 patients, MSCT identified 5 patients (0.43 %) with an anomalous origin of the coronary artery. The left circumflex artery (LCX) originated from the right sinus of Valsalva in 1 patient, and the right coronary artery originated from the left sinus of Valsalva and coursed between the aortic root and the pulmonary artery in 3 patients. In 1 patient, MSCT identified the absence of the LCX and high-grade atherosclerotic stenosis in the right coronary artery. Conclusion MSCT can detect the anomalous origin and course of the coronary artery in relation to the great vessels. It is also useful for identifying atherosclerotic coronary artery disease superimposed on the anomalous vascular system. (Circ J 2005; 69: 320 - 324)
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  • Eri Furukawa, Kiyoshi Hibi, Masami Kosuge, Tomoyori Nakatogawa, Norita ...
    2005 Volume 69 Issue 3 Pages 325-330
    Published: 2005
    Released on J-STAGE: February 25, 2005
    JOURNAL FREE ACCESS
    Background Percutaneous coronary intervention (PCI) of bifurcation lesion has been associated with a low success rate and a high incidence of procedural complications, including side branch occlusion and myocardial infarction. It remains controversial whether preintervention intravascular ultrasound (IVUS) findings can help to identify side branches likely to occlude after PCI of bifurcation lesions. Methods and Results From our IVUS database we identified 81 bifurcation lesions in 72 patients. Side branches were classified into 2 groups: group 1 had ostial side branch stenosis due to atherosclerotic plaque only in the main vessel (n=61), and group 2 had plaque truly involved in the side branch ostium (n=20). There was no significant difference between the 2 groups in the extent of ostial stenosis as assessed by angiography. After PCI, 7 side branches occluded in group 2, compared with 5 side branches occluded in group 1 (35% vs 8%, p=0.003). Conclusion Ostial plaque distribution as assessed by IVUS may be one of the consistent predictors of side branch occlusion after PCI. (Circ J 2005; 69: 325 - 330)
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  • Mitsumasa Hata, Motomi Shiono, Hisakuni Sekino, Hidekazu Furukawa, Aki ...
    2005 Volume 69 Issue 3 Pages 331-334
    Published: 2005
    Released on J-STAGE: February 25, 2005
    JOURNAL FREE ACCESS
    Background Upper gastrointestinal bleeding is a lethal complication after open heart surgery. We designed a prospective randomized trial to test the efficacy of different antisecretory agents to prevent upper gastrointestinal disease after operation. Methods and Results A total of 210 patients were divided into 3 groups: group I had 70 patients who had mucosal protection (teprenone 150 mg/day), group II had 70 patients who had histamine2-receptor antagonist (ranitidine 300 mg/day), and group III included 70 patients who had a proton pump inhibitor (rabeprazole 10 mg/day). Gastric fiberscopy was used in all patients postoperatively during days 5 to 7. We compared the 3 groups in terms of endoscopic findings. Four patients (5.7%) had gastric bleeding complications in each of groups I and II; 2 died of coagulopathy. In group III no patients had gastric bleeding. The incidence of hemorrhagic gastritis was significantly higher in groups I (22.9%) and II (15.7%) than in III (2.9%) (p=0.0003). The incidence of active ulcers was also significantly higher in groups I (28.6%) and II (21.4%) than in III (4.3%) (p=0.0001). Conclusions Early medication postoperative by a proton pump inhibitor was shown to be the most effective treatment and indeed might be described as mandatory to prevent upper gastrointestinal diseases after open heart surgery. (Circ J 2005; 69: 331 - 334)
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  • Kenya Saji, Masahito Sakuma, Jun Suzuki, Tohru Takahashi, Jun Demachi, ...
    2005 Volume 69 Issue 3 Pages 335-338
    Published: 2005
    Released on J-STAGE: February 25, 2005
    JOURNAL FREE ACCESS
    Background There have only been a few reports published on combination therapy for patients with primary pulmonary hypertension (PPH). Methods and Results Fifteen patients with PPH (4 men and 11 women, 34.5±12.1 years old) had received chronic administration of epoprostenol and the additive effects of inhaled nitric oxide (NO) and the hemodynamic changes were evaluated. In addition, the difference in the effect of acute NO loading before and after the epoprostenol therapy was compared in 6 of these patients. Under chronic use of epoprostenol, mean pulmonary arterial pressure, mean right atrial pressure and pulmonary vascular resistance were decreased with acute inhalation of NO. However, cardiac output, mean aortic pressure and systemic vascular resistance were unchanged. As a result, the pulmonary to systemic vascular resistance ratio was reduced. Moreover, after chronic use of epoprostenol, the change (delta) in cardiac output with NO inhalation was increased and the NO-induced decrease in pulmonary vascular resistance was augmented compared to those before the induction. Conclusion Nitric oxide inhalation further improved the hemodynamics when combined with chronic use of epoprostenol in PPH patients. These results suggest the possibility that combination therapies can be used in the treatment for PPH patients. (Circ J 2005; 69: 335 - 338)
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  • Navapun Charuruks, Bunpayao Laohajinda, Suthee Rujiwanitgun, Mathuros ...
    2005 Volume 69 Issue 3 Pages 339-344
    Published: 2005
    Released on J-STAGE: February 25, 2005
    JOURNAL FREE ACCESS
    Background To set a reference value for high-sensitivity C-reactive protein (hs-CRP) in a healthy Thai population and study the effect of time, gender and age on that value. Methods and Results Three hundred and sixty-four subjects, aged between 18 and 74 years, comprising 185 men and 279 women, were studied. Another 10 healthy subjects, aged between 18 and 54 years, were recruited for the study of circadian variation in hs-CRP over the days of the week and the months of a year. The reference value for the Thai adults in the present study was 1.8 mg/L, range 0.2-7.9 mg/L. There was no significant difference in the hs-CRP concentration because of region, time, gender or age (p>0.05), nor was the value affected by time. Conclusion The determination of hs-CRP can be performed at any time and the hs-CRP value determined by this study can be used as the reference for Thai adults. (Circ J 2005; 69: 339 - 344)
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Experimental Investigation
  • Takenori Yao, Takashi Ashihara, Makoto Ito, Kazuo Nakazawa, Minoru Hor ...
    2005 Volume 69 Issue 3 Pages 345-353
    Published: 2005
    Released on J-STAGE: February 25, 2005
    JOURNAL FREE ACCESS
    Background Previous studies have shown that sodium channel (INa) blockade increases ventricular vulnerability; however, there were differences in the degree of the increase. Because the vulnerable window (VW) is altered by the type of preshock refractory gradient (RG), the hypothesis was that the differences in the arrhythmogenesis of INa blockade result from the different types of preshock RG employed. Methods and Results Simulations of regional electric shock following constant pacing stimuli in 2-dimensional bidomain myocardial sheets under INa blockade were conducted using 3 types of preshock RG: longitudinally tilted (LRG), transversely tilted (TRG), and non-tilted RG (NRG). The increase in the degree of INa blockade almost linearly decreased the conduction velocity. The action potential duration in the LRG and TRG cases was non-linearly shortened with the increase in INa blockade because of electrotonic influences, whereas in the case of NRG it was slightly prolonged. In both LRG and TRG cases, the VW for reentry induction by electric shock was considerably widened by the INa blockade; however, this was not the case for NRG in which the VW was rather narrowed by the INa blockade. Conclusion The type of preshock RG alters the degree of the increase in ventricular vulnerability under INa blockade. (Circ J 2005; 69: 345 - 353)
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  • Takeshi Takami, Kazuo Momma, Shinichiro Imamura
    2005 Volume 69 Issue 3 Pages 354-358
    Published: 2005
    Released on J-STAGE: February 25, 2005
    JOURNAL FREE ACCESS
    Background To find a better treatment for patent ductus arteriosus (PDA) in premature infants, the present study investigated the synergism of clinical doses of dexamethasone, indomethacin, and rofecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor, on the fetal ductus arteriosus (DA) in rats. Methods and Results Dexamethasone (0.3 mg/kg), indomethacin (0.3 mg/kg), and rofecoxib (0.3 mg/kg), alone or in combination, were administered to preterm (d19) and near-term (d21) fetal rats. The ratio of the inner diameter of the DA to that of the main pulmonary artery (PA) (DA/PA) was studied at 2, 4 and 8 h after drug administration, using a rapid whole-body freezing method. In near-term rats, the combined administration of dexamethasone and indomethacin caused severe constriction, with a DA/PA ratio of 0.52±0.08 at 8 h, whereas the DA/PA ratios were 0.83±0.03 and 0.90±0.02 with dexamethasone and indomethacin, respectively. Combined administration of dexamethasone and rofecoxib also caused severe constriction, with a DA/PA ratio of 0.64±0.07 at 8 h, compared with the DA/PA ratio of 0.92±0.03 with rofecoxib alone. Conclusions Combined therapy may be an option in the medical management of PDA in premature infants before considering surgical treatment. (Circ J 2005; 69: 354 - 358)
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Case Report
  • Kosuke Tsukamoto, Akitoshi Ohara, Jiro Kajikawa, Satoru Munakata, Ayak ...
    2005 Volume 69 Issue 3 Pages 359-361
    Published: 2005
    Released on J-STAGE: February 25, 2005
    JOURNAL FREE ACCESS
    A 20-year-old man with congestive heart failure (CHF) and hypertension (HT) was admitted to hospital. Ultrasonic echocardiography showed that he had aortic stenosis caused by a bicuspid aortic valve. The plasma renin concentration was slightly elevated, and enhanced magnetic resonance imaging and renography revealed a hypoplastic kidney that had almost lost its normal function. It is postulated that the increased afterload and preload of the left ventricle induced by both of these abnormalities contributed to the onset of CHF and HT. Pharmacological therapy alone failed to control the CHF and HT, but surgical removal of the hypoplastic kidney was effective in reducing the plasma renin concentration and treating the CHF and HT. (Circ J 2005; 69: 359 - 361)
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  • Osamu Monta, Goro Matsumiya, Norihide Fukushima, Yuji Miyamoto, Yoshik ...
    2005 Volume 69 Issue 3 Pages 362-364
    Published: 2005
    Released on J-STAGE: February 25, 2005
    JOURNAL FREE ACCESS
    A 29-year old woman developed severe congestive heart failure in the first week after an uneventful full-term delivery. Despite intense medical treatment over the next 6 months, her heart failure symptoms gradually worsened and she eventually developed cardiogenic shock. She successfully underwent the implantation of a left ventricular assist system, but because there was no sign of recovery of ventricular function, she was placed on the waiting list for heart transplantation. After 143 days of support, she suffered from brain hemorrhage, and eventually died after a total of 321 days of left ventricular support. Postmortem examination of the myocardium showed sustained diffuse fibrosis and no inflammatory reaction. This case implies that with severe peripartum cardiomyopathy heart transplantation should be considered without delay even if a mechanical assist system is available. (Circ J 2005; 69: 362 - 364)
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  • Kenya Sakai, Hiroyuki Ochiai, Norihiko Katayama, Kenji Nakamura, Keiko ...
    2005 Volume 69 Issue 3 Pages 365-367
    Published: 2005
    Released on J-STAGE: February 25, 2005
    JOURNAL FREE ACCESS
    An 84-year-old woman was admitted with anorexia and because the serum cardiac markers, electrocardiogram and echocardiography suggested acute myocardial infarction she underwent emergency cardiac catheterization. Coronary angiography revealed no significant coronary artery stenosis, but left ventriculography revealed akinesis of the left ventricular apex with shunt flow to the right ventricle. The diagnosis was a rare case of takotsubo cardiomyopathy complicated by ventricular septal perforation. The patient died of cardiogenic shock on the day of admission day. (Circ J 2005; 69: 365 - 367)
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  • Shu Wakino, Kei Tawarahara, Naoto Tsuchiya, Yoshitomo Kurosawa, Tatsuo ...
    2005 Volume 69 Issue 3 Pages 368-372
    Published: 2005
    Released on J-STAGE: February 25, 2005
    JOURNAL FREE ACCESS
    A 36-year-old woman developed multiple spontaneous arterial dissections in both renal arteries, the carotid artery, superior mesenteric artery, and vertebral artery, but not the aorta, and she suffered a renal infarction and subarachnoid hemorrhage within a short period of time. She had been undergoing frequent injections of human chorionic gonadotropin and human menopausal gonadotropin, together with oral estrogen therapy, during a 5-year infertility treatment regimen. As she had no other history of any disorder affecting the arterial walls, this therapy is suspected to have caused the multiple arterial deformities. Although cases of isolated arterial dissection are occasionally reported, it is rare for multiple dissections and serious symptoms to occur simultaneously. (Circ J 2005; 69: 368 - 372)
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