Background There have been many cases of pulmonary thromboembolism (PTE) that were not diagnosed in the acute phase and not classified as chronic thromboembolic pulmonary hypertension (CTEPH). The aim of the present study was clarify the clinical characteristics of chronic PTE. Methods and Results The study subjects were 601 patients (chronic PTE =92, acute PTE =456, CTEPH =53) who were clinically diagnosed before their death. Dyspnea and chest pain, which are frequently found in acute PTE, were found less frequently in chronic PTE. The diagnosis of chronic PTE is often delayed in cases of mild to moderate severity with atypical onset. Chronic heart failure and chronic respiratory failure were most frequent in chronic PTE, and cerebrovascular disease was present in approximately 15% of the cases of chronic PTE. Pulmonary angiography and ventilation lung scan were used least frequently in acute PTE. Heparin and thrombolysis were used most frequently in acute PTE. Conclusions Besides the atypical onset and reduced severity, the presence of preexisting diseases may be one of the reasons why the diagnosis for chronic PTE is delayed. The diagnostic and management techniques differ according to the type of PTE. (Circ J 2005; 69: 1009 - 1015)

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Background The Japan Lipid Intervention Trial was a nationwide cohort study of 52,421 hypercholesterolemic patients treated with open-labeled simvastatin for 6 years under standard clinical practices. Cerebrovascular disease (CVD) is one of the leading causes of death in Japan, but the effect of hypercholesterolemia on CVD has not been well established in Japanese patients. This study aimed to determine the relationship between the risk of CVD and serum lipid concentrations during treatment in Japan. Methods and Results Patients were treated with 5-10 mg/day of simvastatin and all, including those who discontinued simvastatin for any reason, had their lipid concentrations and incidence of CVD monitored for 6 years. Data of 41,088 patients were analyzed in this study, excluding those who had a history of coronary heart disease or CVD. The risk of cerebral infarction was higher in patients whose mean total cholesterol concentrations during treatment were ≥240 mg/dl, low-density lipoprotein cholesterol concentrations ≥160 mg/dl, triglycerides ≥150 mg/dl and high-density lipoprotein cholesterol concentrations <40 mg/dl. There was no obvious correlation between cerebral hemorrhage and serum lipid concentrations. Conclusion Improvement of serum lipid concentrations is important for reducing the incidence of cerebral infarction. (Circ J 2005; 69: 1016 - 1021)

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Background This study was designed to determine the utility of transthoracic Doppler echocardiography (TTDE) in evaluating angiographic Thrombolysis in Myocardial Infarction (TIMI) frame count as a quantitative index of coronary reperfusion in patients with anterior acute myocardial infarction (AMI) before mechanical reperfusion. Methods and Results Color and pulsed TTDE was performed to evaluate distal left anterior descending coronary artery (LAD) reperfusion in 56 consecutive patients with a first anterior AMI before coronary intervention, and these findings were compared with the corrected TIMI frame count (cTFC) by subsequent angiography. Twenty-four of the 56 patients had LAD reperfusion (TIMI 2 or 3) by angiography. Visual antegrade distal LAD flow by color TTDE was detected in 21 of these 24 patients. In the 21 patients, diastolic peak velocity of the distal LAD flow by pulsed TTDE showed a significant correlation with cTFC by angiography (r=-0.74, p<0.001). The diagnosis of high risk with angiographic cTFC >40 by distal LAD peak velocity <21 cm/s using TTDE had a sensitivity, specificity, and accuracy of 82%, 93%, and 91%, respectively. Conclusion TTDE enables noninvasive and quantitative evaluation of distal LAD reperfusion in patients with anterior AMI in the acute phase before mechanical reperfusion. (Circ J 2005; 69: 1022 - 1028)

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Background Recently, the 5-lipoxygenase activating protein gene (ALOX5AP) was reported to confer a risk of myocardial infarction (MI) and stroke, independent of conventional risk factors. The purpose of the present study was to validate those findings in a Japanese population. Methods and Results The study population consisted of 1,875 subjects (males 871, females 1,004) recruited from the Suita study (control group) and 353 subjects (males 306, females 47) with MI. The promoter, all of the exons, and 3'UTR regions of ALOX5AP were sequenced in 96 subjects, and 8 polymorphisms were found. There were significant differences in the frequencies of the haplotypes constructed from the 2 SNPs (A162C and T8733A) between the control and MI groups. Multiple logistic analysis indicated that the homozygous genotype of the (CA) haplotype was significantly associated with a reduced risk for MI. Conclusion The hypothesis that ALOX5AP contributes to susceptibility for MI was validated in a Japanese population. (Circ J 2005; 69: 1029 - 1034)

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Background Interstitial collagen, especially type I, is a major component of atherosclerotic plaques and the matrix metalloproteinases (MMP) 1, 8 and 13 can initiate collagen breakdown. MMP-8 degrades type I collagen preferentially and more potently than MMP-1 or MMP-13. Although MMP-8 was thought to be produced only by neutrophils, it was recently reported to also be produced by endothelial cells, smooth muscle cells and macrophages in plaques. Methods and Results Plasma MMP-8 concentrations were measured in 250 patients undergoing coronary angiography for coronary artery disease (CAD: >50% stenosis), which was found in 181 patients, of whom 69 had 1-vessel, 66 had 2-vessel, and 46 had 3-vessel disease. Compared with 69 patients without CAD, the 181 with CAD had higher MMP-8 concentrations (3.5 vs 3.0 ng/ml, p<0.001). There was a stepwise increase in MMP-8 concentration depending on the number of stenotic vessels: 3.2 in 1-vessel, 3.6 in 2-vessel, and 4.3 ng/ml in 3-vessel disease (p<0.001). Multivariate analysis showed that MMP-8 concentration was independently associated with CAD. The odds ratio for CAD was 1.22 (95%confidence interval =1.07-1.39) for a 1 ng/ml increase in MMP-8 concentration. Conclusions Plasma MMP-8 concentration is associated with the presence and severity of CAD. (Circ J 2005; 69: 1035 - 1040)

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Background The transmural distribution of myocardial perfusion is important for predicting the contractile reverse of an infarcted wall in reperfused acute myocardial infarction (AMI). Evaluating transmural myocardial perfusion by myocardial contrast echocardiography (MCE) could predict the long-term recovery of left ventricular (LV) function. Methods and Results The study group comprised 20 consecutive patients with a first-episode anterior AMI with total occlusion of the proximal left anterior descending artery, who underwent successful percutaneous coronary intervention within 24 h of onset. MCE was performed on the 15th day after the onset, using ultraharmonic gray-scale imaging with intermittent end-systolic triggering every 4 beats or every 6 beats. Regions of interest were placed over both the endocardial and epicardial region at the mid-septal level. Regional wall motion (RWM) of the infarcted anterior wall and global LV function were assessed by 2-dimensional echocardiography and left ventriculography in both the acute and chronic phase. The transmural distribution of myocardial perfusion by MCE demonstrated a significant relation with RWM score index (r=0.75, p=0.0004). Recovery of RWM and LV ejection fraction (LVEF) at 6 months after reperfusion was significantly greater in the group with good perfusion of the epicardium according to MCE than in the poor perfusion group [RWM (SD/cord); -1.23±0.91 vs -3.51±0.84, p=0.001, LVEF (%); 63.8±10.4 vs 47.0±3.4, p=0.04]. Conclusions Assessing the transmural distribution of myocardial perfusion by MCE can predict the long-term recovery of LV function after a reperfused AMI. (Circ J 2005; 69: 1041 - 1046)

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Background The diagnosis of acute coronary syndrome (ACS), especially non-ST-elevation myocardial infarction and unstable angina in the emergency department (ED) still remains a challenge. Multislice computed tomography (MSCT) allows assessment of not only coronary artery stenoses and occlusions, but also assessment of coronary artery plaques and myocardial perfusion status. Methods and Results MSCT was performed in 31 patients who were admitted to the ED because of chest pain persisting at least 30 min and non-diagnostic ECG changes and normal serum enzyme concentrations. Using MSCT, ACS was defined by coronary artery stenosis ≥75% accompanied by computed tomography (CT)-low-density plaques, and/or by the presence of myocardial perfusion defects. ACS was confirmed by coronary stenosis ≥75% by coronary angiography and/or subsequent elevation of troponin I concentration. In total, 22 patients were diagnosed as having ACS. MSCT detected stenoses with CT-low-density plaques in 21 and non-transmural myocardial perfusion defect in 3 patients. There was 1 false-positive and 1 false-negative result. The sensitivity and specificity of MSCT to identify ACS was 95.5% and 88.9%, respectively. Conclusion MSCT provides diagnostic operating characteristics suitable for triage of patients with ACS in the ED. (Circ J 2005; 69: 1047 - 1051)

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Background Abnormal sleep dynamics in patients with heart failure is one of the mechanisms for the relative predominance of central sympathetic outflow over parasympathetic tone. This study was designed to examine whether central sympathoinhibition could improve the sympathovagal imbalance related to rapid-eye-movement (REM)/non-REM ultradian sleep rhythm in these patients. Methods and Results Beat-by-beat RR intervals of overnight electrocardiogram were serially subject to power spectral analysis in 14 patients with chronic heart failure and 13 age-matched subjects with normal cardiac function. To assess autonomic sleep dynamics, the ultradian rhythm was extracted from all-night consecutive high-frequency (HF) components of heart rate variability (HRV) before and after administration of an _α2-adrenergic agonist, guanfacine. Night-time HRV in heart failure was characterized by an attenuated ultradian rhythm of HF-components with a concomitant reduction in averaged HF power. Guanfacine reduced blood pressure, heart rate, and plasma norepinephrine concentrations by 7%, 8%, and 34% (p<0.01), respectively. After guanfacine, HF power rose by 154% (p<0.01) with a prominent augmentation of the all-night ultradian rhythm (+361%, p<0.01). Conclusions Central sympathoinhibition augments a sleep-related ultradian rhythm of parasympathetic tone, suggesting a potential benefit to autonomic balancing and sleep quality in patients with chronic heart failure. (Circ J 2005; 69: 1052 - 1056)

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Background Segmental pulmonary vein (PV) isolation has been performed to eliminate paroxysmal atrial fibrillation (AF). However, this technique is not effective in most patients with persistent AF. Methods and Results Left atrial catheter ablation (LACA) was performed by encircling the left- and right-sided PV 1-2 cm from the ostia, guided by an electroanatomical mapping system in 16 patients with persistent AF (>1 month). Twelve patients (75%) had a history of unsuccessful transthoracic cardioversion and prophylactic antiarrhythmic drugs. Ablation lines were also created in the mitral isthmus and posterior LA. PV isolation was also performed for each PV if there were residual PV potentials after the LACA. After LACA, 38 PV (59%) were completely isolated, and complete PV isolation was achieved with only a few radiofrequency energy applications (2.7±2.0 min) on a narrow area of the PV ostium (24±15%) in the remaining PV. The mean procedure time was 200±38 min. During the follow-up period (17±3 months), 12 patients (75%) had normal sinus rhythm and were free of symptomatic AF with (n=10) or without antiarrhythmic drugs (n=2). One patient had a stroke just after the procedure. No other complications including PV narrowing (>50%) occurred. Conclusion This approach was effective in persistent AF, however, concomitant use of antiarrhythmic drugs was often required. (Circ J 2005; 69: 1057 - 1063)

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Background Electrocardiograms (ECGs) recorded from the higher intercostal spaces (ICSs) are reported to be helpful for the diagnosis of Brugada syndrome (BS). However, the prevalence of Brugada-type ECG changes recorded from the higher ICSs is unknown in the healthy Korean population. Methods and Results A total of 225 healthy Korean male subjects with a mean age of 44±13 (20-69) years with no syncope or family history of sudden death were enrolled in the present study. ECGs were taken from 4th, 3rd, and 2nd ICSs and examined for Brugada-type ECG changes. There were none on the routine 12-lead ECGs, but 3 (1.3%) of the 225 subjects had a Brugada-type ECG recorded from the higher ICSs and 1 of them had a Brugada-type ECG recorded at both the 2nd and 3rd ICSs. The prevalence of the Brugada-type ECG was 1.3% at the 3rd ICS, 0.4% at the 2nd ICS. All were type 2. Conclusion Some healthy Korean males with normal routine ECGs show Brugada-type 2 changes on ECGs recorded from higher ICSs. (Circ J 2005; 69: 1064 - 1067)

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Background Multislice computed tomography coronary angiography (CTCA) is reconstructed by ECG gating and consequently it is difficult to obtain coronary artery images from patients with arrhythmias, such as atrial fibrillation (AF), by the conventional method. Methods and Results Eleven patients with AF (9 males, 2 females; mean age: 62.5 years) underwent CTCA using a slice thickness of 0.5 mm, gantry rotation of 0.4 or 0.5 s/rot and pitch of 3.2-4.0. A segmented reconstruction method was used to construct CTCA images at the conventional relative 70-75% (mid-diastolic phase) and 30-35% (end-systolic phase) of the R-R interval and furthermore, the absolute mid-diastolic phase and end-systolic phase from the R wave. Three investigators, who were unaware of the coronary angiography results, independently evaluated the curved multiplanar reconstruction (MPR) images. In both the relative and absolute phase reconstruction, there were motion artifacts in the mid-diastolic than in the end-systolic phase. The absolute phase images had less motion artifacts than the conventional relative phase images. Optimal curved MPR images were obtained in the absolute end-systolic phase. The quality and motion artifacts of those optimal images from AF patients were similar to those from patients in sinus rhythm. Conclusion The absolute end-systolic phase is the best time to get optimal CTCA images in AF patients. (Circ J 2005; 69: 1068 - 1073)

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Background The purpose of this study was to evaluate the short- and long-term results of radiofrequency catheter ablation (RFCA) for the treatment of atrial fibrillation (AF) in patients with mitral stenosis (MS) following percutaneous transvenous mitral commissurotomy (PTMC). Methods and Results Four patients (2 males, age 59±6 years) underwent simultaneous PTMC and pulmonary vein (PV) ablation. All patient had AF and MS (2 had persistent AF >1 month, 2 had paroxysmal AF), and the mean duration of AF was 3.4±3.3 years. The mean left atrial dimension was 47±7 mm and the mean ejection fraction was 58±4%. After PTMC, RFCA was performed in all patients (3 underwent PV isolation and 1 had PV focal ablation). The mitral valve area increased from 1.11 ±0.19 to 1.90±0.20 cm² (p<0.01). The frequency of AF episodes was dramatically reduced in the 2 patients with paroxysmal AF, and the 1 with persistent AF maintained sinus rhythm, but 1 patient with persistent AF developed recurrent AF. No complications or cardiac events occurred in any of the patients. Conclusion The combination of RFCA and PTMC was safe and feasible, and may be useful in patients with MS and AF. (Circ J 2005; 69: 1074 - 1078)

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Background The effects of endoscopic transthoracic sympathicotomy (ETS) on plasma natriuretic peptides concentrations in humans were examined in order to elucidate the role of the sympathetic nervous system in their regulation. Methods and Results Thirty-seven patients with palmar hyperhidrosis underwent ETS. Cardiac functional indices were assessed by echocardiography, and plasma atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) concentrations were measured before and after ETS. ETS caused decreases in heart rate, mean arterial pressure, systemic vascular resistance, and increases in left ventricular (LV) end-diastolic volume, stroke index, ejection fraction, and left atrial diameter. LV end-systolic volume and cardiac index remained unchanged. Following ETS, ANP increased from 10.7±5.9 to 24.7±16.8 pg/ml (p<0.01), and BNP increased from 5.1±4.2 to 19.7±21.5 pg/ml (p<0.01). From the multivariate regression analysis, ETS, age and gender were determined to be significant predictors of changes in the ANP and BNP concentrations. None of the hemodynamic parameters were useful as independent predictors. Conclusion The plasma concentrations of ANP and BNP increased after ETS, independent of hemodynamic changes, and apparently because of the release of the inhibitory effects of the cardiac sympathetic nerves on natriuretic peptide secretion. (Circ J 2005; 69: 1079 - 1083)

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Background It is known that approximately two-thirds of patients with vasovagal syncope have prodromal symptoms and when these start, physical maneuvers that can increase venous return may abort the syncopal attack. The aims of this study were to evaluate the effects of 3 physical maneuvers, squatting, leg-crossing with muscle tensing, and handgrip, on improving hemodynamic status, and to compare the effect of each on aborting or preventing vasovagal syncope. Methods and Results Of 50 patients who underwent the head-up tilt test (HUT) to evaluate syncope, 27 patients with positive HUT were classified as group I (14 men, 13 women; mean age 44.5±15.3 years), 23 patients with negative HUT were classified as group II (13 men, 10 women; mean age 41.2 ±16.7 years), and 21 normal subjects were classified as group III (10 men, 11 women; mean age 28.6±6.3 years). The effects of the physical maneuvers were evaluated in 21 patients from group I who underwent a repeat HUT 1 week after the initial test. Leg-crossing significantly increased systolic blood pressure (SBP) in all 3 groups (8.0±5.8 mmHg in group I, 7.0±8.5 mmHg in group II, 8.7±5.7 mmHg in group III; p<0.05), but not diastolic blood pressure (DBP). Squatting significantly increased SBP and DBP in all 3 groups (7.1 ±5.1, 4.6±5.8 mmHg in group I, 7.8±5.9, 4.3±4.7 mmHg in group II, 6.5±5.0, 3.7±3.9 mmHg in group III; p<0.05). However, handgrip did not exert any significant influence on the hemodynamics in any group nor did heart rate change significantly during the physical maneuvers in any group. During the repeat HUT, prodromal symptoms with hypotension developed in 13 of the 21 patients and of these 5 fainted immediately after and were not able to do the physical maneuvers. Squatting and leg-crossing aborted syncope in 7 of 8 patients, but handgrip aborted syncope in only 1 patient. Conclusion Squatting and leg-crossing with muscle tensing improved the hemodynamics of normal subjects as well as those of patients with vasovagal syncope. Squatting and leg-crossing can be used as a simple and effective preventive maneuver in patients with vasovagal syncope. (Circ J 2005; 69: 1084 - 1088)

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Background Patients with cyanotic congenital heart disease (C-CHD) usually have myocardial thickening and fibrosis, both of which can affect the course of surgical management. Hypoxia and ischemia may stimulate microvessel formation in the myocardium, which may accelerate the myocardial thickening and fibrosis. Whether hyperplasia of microvessels occurs in the myocardium of C-CHD was investigated in this report. Methods and Results The patients were divided into 2 groups; the C-CHD group (n=22), and the acyanotic congenital heart disease (A-CHD) group (n=24). The microvessels and vascular endothelial growth factor (VEGF) mRNA of the myocardium were detected by immunohistochemical staining assay and real-time quantitative reverse transcriptase polymeric chain reaction, respectively. The serum VEGF levels were measured by using enzyme-linked immunosorbent assay. The results were that: (1) the number of microvessels in the myocardium were more in the C-CHD group than in A-CHD group; (2) the serum VEGF levels in the C-CHD group vs the A-CHD group were higher in the preoperative period (p<0.001), but there was no difference after operation; and (3) VEGF protein and the expression of VEGF mRNA in the myocardium were higher in the C-CHD group than in the A-CHD group (p<0.01). Conclusions Myocardial microvessels formed in the myocardium of patients with C-CHD, possibly mediated by increasing VEGF levels (for this group of patients). (Circ J 2005; 69: 1089 - 1093)

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Background The left ventricular (LV) diastolic performance of infants who were in a stable post-treatment condition in the neonatal intensive care unit was evaluated using echocardiography. Methods and Results The study group comprised 55 infants (Stable infant group, SI) and the parameters of LV performance were: LV propagation velocity (Vp) by color M-mode Doppler echocardiography (CMD), peak E wave, peak A wave, and the E/A ratio of transmitral flow. In a second set of measurements, a subset of 10 infants (patent ductus arteriosus (PDA) infant group, PI) were evaluated for LV diastolic performance during closure of PDA. The mean Vp in the SI was 27.2±7.3 cm/s and a positive correlation was observed between Vp and gestational age (r=0.477, p=0.0002). In the PI, Vp did not change significantly during closure of the PDA (from 23.3±8.2 cm/s to 27.5±8.4 cm/s); however, the E/Vp ratio decreased significantly with closure (from 3.14±0.83 to 2.12±0.68, p=0.0051). Conclusion The measurement of Vp by CMD can be considered a parameter for the evaluation of LV diastolic performance, even in the neonatal period. The LV diastolic performance of the infant is maintained from immediately after birth to spontaneous closure of the PDA. (Circ J 2005; 69: 1094 - 1098)

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Background A prospective study examined whether a combination of an exercise program and heparin administration improves the clinical symptoms of patients with arteriosclerosis obliterans (ASO) without an indication for surgical revascularization because of the lack of distal target vessels or other reasons such as high surgical risk or lack of a vein conduit from previous coronary artery bypass surgery. Methods and Results A total of 19 consecutive patients with symptomatic non-option ASO diagnosed by angiography were randomly assigned to 3 groups: heparin + exercise (walking for 60 min after heparin injection [3,000 units/day IV for 14 days], n=6), heparin administration only (n=6), and exercise only (n=7). Plasma levels of hepatocyte growth factor (HGF) were serially measured before and after intravenous administration of heparin. Ankle brachial pressure index was measured and treadmill exercise test (2.5 km/h, 12% slope) was performed before the 2-week treatment, just after finishing treatment, and 12 weeks after beginning the treatment. Ophthalmic examinations, including visual acuity test, ocular fundoscopy and fluorescein angiographic fundus photography, were performed before and 12 weeks after the treatment program. In all patients, HGF levels increased more than 4-fold of the basal level at 30 min after heparin injection. Maximum walking time was significantly higher in the heparin + exercise group than in the other 2 groups (p<0.05). There were no patients who showed pathological retinal angiogenesis. Conclusion The combination of an exercise program and heparin administration improves the clinical symptoms of patients with non-option ASO. (Circ J 2005; 69: 1099 - 1104)

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Background Aerobic exercise enhances endothelium-dependent vasodilation in healthy individuals. It is thought that exercise increases nitric oxide (NO) production and decreases NO inactivation, leading to an increase in NO bioavailability. Angiotensin II and NO have important roles in maintaining vascular tone. There are polymorphisms of the angiotensin converting enzyme (ACE) gene and the presence of the deletion (D) allele has been associated with higher concentrations of circulating and tissue ACE. In this study, the relationship between endothelial function and ACE gene polymorphisms was investigated in athletes and sedentary subjects. Methods and Results The study group comprised 56 endurance athletes and 46 sedentary subjects who underwent brachial artery ultrasonographic examination. ACE insertion (I) and D allele frequencies were analyzed in all patients. Baseline brachial artery diameter and resting blood flow were similar in athletes and controls (p>0.05). The flow-mediated dilation (FMD) was 8.48±3.65% in athletes and 5.16±2.5% in controls (p=0.0001). FMD was significantly different between ACE genotypes in the athletes (p<0.0001): it was higher in ACE II (10.5±1.6%) subjects than in the DI (8.4±2.3%) or DD (7±1.2%) subgroups. Conclusion Regular isotonic exercise can improve endothelium-dependent vasodilation especially in those with the ACE II genotype. (Circ J 2005; 69: 1105 - 1110)

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Background Cardiac pacemaker and defibrillator leads are inserted through extrathoracic subclavian venipuncture using ultrasound (US) guidance, but there can be complications. The purpose of this study was to investigate a safer and improved implanting procedure. Methods and Results Venipuncture guided by US with a 7.5 MHz convex transducer was performed to implant 32 leads in 18 patients. US enabled identification and location of the vein and needle tip during puncture and clarified the reasons for unsuccessful venipuncture. Venipuncture was successful on the second attempt or within 2 min in 90.6% (29/32) and 84.4% (27/32) of lead placements, respectively, although the vein was small (mean, 7.8 mm), deep (mean, 22.7 mm), and required a large angle of entry (mean, 52.4). The subclavian artery or lung was adjacent to the vein in 50.0% and 27.8% of cases, respectively. The flexible wall of the vein interfered with the penetration of the needle in 33.3% of cases. It was often difficult to locate the needle tip because of poor visualization. Conclusions Ultrasound guidance of subclavian venipuncture enables a safe and time-saving procedure by visualizing not only the needle but also the vein and surrounding structures, although further modifications of the needle are needed for better visualization. (Circ J 2005; 69: 1111 - 1115)

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Background Phospholamban is a reversible inhibitor of the Ca²⁺-ATPase of the cardiac sarcoplasmic reticulum (SR) and contributes to the regulation of heart muscle contractility. Because only the monomeric form, not the pentameric form, of phospholamban inhibits the Ca²⁺-pumping activity of the SR, it is important to understand the dynamic equilibrium between these 2 forms. Methods and Results The effects of various detergents and phospholipids on the oligomeric state of phospholamban were examined. Among the detergents examined, 3-[(3-cholamidopropyl) dimethylammonio]-1-propanesulfonate (CHAPS) stabilized the pentameric form whereas octylglucoside was an effective inducer of dissociation into the monomer. On the basis of these properties of the 2 detergents, the effects of various phospholipids on the oligomeric state of phospholamban with the use of mixed micelles containing octylglucoside or CHAPS were examined. Among the 8 phospholipids examined, phosphatidic acid was an effective inducer of pentamer dissociation, whereas the other phospholipids exhibited pentamer-stabilizing activity. Lysophosphatidylcholine, lysophosphatidylethanolamine, and phosphatidylglycerol were highly effective stabilizers of the pentamer. Conclusions The phospholipids in the SR membrane are important determinants of the equilibrium between the monomeric and pentameric forms of this protein. The results suggest that the metabolism of phospholipids in the cardiac SR may contribute to regulation of heart muscle contractility by shifting this equilibrium. (Circ J 2005; 69: 1116 - 1123)

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Background The aims of the present study were to assess the effect of the stent diameter, convolution kernel, and vessel orientation to the z-axis on the evaluation of coronary stents, in vitro with computed tomography (CT) angiography. Methods and Results Seven vascular models (2 models without stenosis, 2 with obstruction, and 3 with stenosis) with an approximate inner diameter of 3 or 4 mm, filled with contrast material (79 or 330 HU) were scanned with a 16-detector CT. The diameter measurement of the stent lumen and stenosis evaluation were both done in an orientation parallel to the z-axis of the scanner using 4 convolution kernels. The measured diameters of the stented lumen were 47-57% and 36-45% smaller than the actual inner diameter of the 3- and 4-mm diameter models, respectively. The diameter measurement of the stent lumen and visualization of the in-stent stenosis were improved by using convolution kernels with higher spatial resolution. The in-stent artifacts were evaluated in 4 orientations (0°, 30°, 60°, 90°) to the z-axis. The artifact was the minimum in 0° to the z-axis, and the maximum in 90°. Conclusion Visualization of the lumen of a stent by CT is affected by its diameter, convolution kernel, and vessel orientation to the z-axis, and these factors should be taken into consideration in the stent evaluation. (Circ J 2005; 69: 1124 - 1131)

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Background Mitochondrial Ca²⁺ overload is a major cause of irreversible cell injury during various metabolic stresses. The protective effects of various agents that affect mitochondrial function against Ca²⁺ overload during Ca²⁺ paradox were investigated in rat ventricular myocytes. Methods and Results On Ca²⁺ repletion following Ca²⁺ depletion, [Ca²⁺]_i increased rapidly, and 90 of 210 cells (43%) died. In viable cells, the increase in [Ca²⁺] _i was lower than in dead cells. KB-R7943 prevented the increase in [Ca²⁺]_i, and completely inhibited cell death. Ruthenium red (RuR), diazoxide (Dz) or cyclosporin A (CsA) prevented cell death (15%, 26% and 17%, respectively; p<0.05), and the protective effect of Dz was abolished by 5-hydroxydecanoate. These agents did not reduce the increase in [Ca²⁺]_i in viable cells or the rate of initial increase in [Ca²⁺] _i in all cells. RuR and Dz decreased [Ca²⁺] _m in skinned myocytes, but CsA did not affect [Ca²⁺] _m. Dz reduced NADH fluorescence, whereas RuR and CsA did not. Conclusions The protective effects of RuR and Dz could be ascribed to altered Ca²⁺ regulation by decreasing [Ca²⁺]_m, and Dz could have an additional effect on oxidative phosphorylation. The protective effect of CsA could be directly associated with the mitochondrial permeability transition pore. (Circ J 2005; 69: 1132 - 1140)

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Multislice spiral computed tomography (MSCT) permits the noninvasive visualization of coronary artery stenoses and occlusions, as well as atherosclerotic plaques, in patients with coronary artery disease. This report describes a patient with stable angina pectoris in whom the regression of the plaque and coronary artery remodeling was documented by serial MSCT. (Circ J 2005; 69: 1141 - 1143)

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A case of non-Q myocardial infarction in a previously healthy 17-year-old body builder, who used clenbuterol, a long-acting β₂ adrenergic agonist with anabolic and lipolytic effects, is reported. Only 1 case report of myocardial infarction associated with the use of clenbuterol was found in a literature review and that case was, however, associated with anabolic steroid use. This is the first case report to describe myocardial infarction in a young male body builder only taking clenbuterol. (Circ J 2005; 69: 1144 - 1146)

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A 54-year-old-man experienced serial ischemic embolic strokes and retinal artery embolism in the left carotid territory. In the acute phase, intraluminal thrombus in the left carotid siphon and frequent microembolic signals (MES) in the left middle cerebral artery were detected with magnetic resonance angiography (MRA) and transcranial Doppler (TCD). The patient was initially treated with only heparin for 3 days; however, more than 30 MES per 30 min were still detected. After adding ticlopidine as an antiplatelet therapy, MES were suppressed completely. After starting combination therapy of heparin (later warfarin) and ticlopidine, repeated MRA confirmed resolution of carotid thrombus and ischemic stroke did not recur. For management of intraluminal thrombus in the carotid artery, MES with TCD was useful in evaluating the risk of distal embolism. Combination treatment with anticoagulants and ticlopidine can both resolve the thrombus and prevent distal embolism. (Circ J 2005; 69: 1147 - 1149)

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Chronic disseminated intravascular coagulation (DIC) is a well-known complication of aortic aneurysm. A 63-year-old man with bleeding tendency and a large palpable abdominal aortic aneurysm (AAA) was diagnosed as having fibrinolysis dominant DIC by the excessive activation of both coagulation and fibrinolysis (plasmin -_{α 2} plasmin inhibitor complex concentration is usually >4 symbol>mg/ml). Although several treatments were tried, DIC could not be controlled until the patient was given combined therapy of danaparoid (1,250 U/12 h, bolus IV) and tranexamic acid (0.5 g × 3/day, oral administration). This therapy may be beneficial when control for bleeding is required without restricting the ambulatory movement of patients by continuous drip. (Circ J 2005; 69: 1150 - 1153)

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Background The relationship between adiponectin and coronary spastic angina (CSA), both of which are closely involved in coronary endothelial dysfunction, has not been elucidated. Methods and Results Plasma adiponectin concentrations were examined in 55 men with CSA and 55 with chest pain syndrome (CPS). The plasma log-adiponectin levels were significantly lower in patients with CSA than with CPS (0.61±0.28 vs 0.80±0.21 μg/ml, p<0.0001). The prevalence of smoking was significantly higher in the CSA patients than in those with CPS (50.9% vs 29.1%, p=0.0195). In multiple logistic regression analysis, log-adiponectin (p=0.0008) and smoking (p=0.0210) were independent determinants of CSA. Conclusions Hypoadiponectinemia is a potential risk factor for CSA in men, independent of smoking. (Circ J 2005; 69: 1154 - 1156)

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