Background To improve the long-term results of coronary artery bypass grafting (CABG), several arterial conduits have been used, including the skeletonized right gastroepiploic artery (GEA) graft. Methods and Results The skeletonized GEA graft was used for CABG in 223 patients over a 6-year period (208 males, 15 females, mean age 64 years). 1-, 2- and 3-vessel and left main trunk disease was noted in 1, 28, 122 and 72 patients, respectively. Internal thoracic artery, radial artery and saphenous vein grafts were concomitantly used in 217 (97%), 73 (33%) and 41 (18%) patients, respectively, and the mean number of grafts was 3.5. The sites of GEA grafting were 1 anterior descending, 10 diagonal, 97 circumflex, and 185 right coronary arteries, with 154 single in-situ, 33 free and 36 composite grafts, including 56 sequential grafts. There was 1 (0.4%) operative death. New Q wave was noted in 2 (0.9%) patients. Postoperative angiography revealed 97.6% early postoperative (within 1 month) and 91.5% midterm (mean 27 months) patency rates for GEA grafts. The cumulative 4-year patency rate of the skeletonized GEA graft was 86.4%. Conclusion The skeletonized GEA is a safe and effective arterial conduit for CABG. (Circ J 2007; 71: 1503 - 1505)

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Background The purpose of this study was to investigate the changes in sleep characteristics in patients who underwent coronary artery bypass grafting (CABG) surgery, using both subjective and objective tests in the early (preoperative) and late (postoperative) periods. Methods and Results Forty-five patients who underwent CABG and did not previously have any sleep disturbance were evaluated by subjective and objective sleep parameters during a consecutive 3-5-day preoperative examination, during a consecutive 5-8-day period in the 1^st postoperative week, and during consecutive 5-8-day periods in the 1^st and 2^nd postoperative months. The Pittsburgh Index and Epworth Sleepiness Scale values, sleep latency, napping episodes, total napping period, duration of wakefulness after sleep onset and fragmentation index values were significantly increased; however, Maintenance of Wakefulness Test lengths, total sleep time and sleep efficiency were significantly decreased in the 1^st postoperative week. All of these were the same in the 1^st postoperative month and differences were not statistically different from the preoperative period. None of the sleep parameters in the 2^nd postoperative month differed from the values obtained in the preoperative period. Conclusion The cause of sleeplessness after CABG surgery may be temporary deterioration of circulation in the centers of the brain stem and hypothalamus that control sleep and awakening. Improvement of the circulation in these centers a few months after the operation helps to regain sleep control, and thus sleep disturbances disappear. (Circ J 2007; 71: 1506 - 1510)

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Background This study assessed the neurologic and cosmetic outcome of the endoscopic radial artery harvesting (ERH) technique in coronary artery bypass grafting (CABG). Methods and Results The study group comprised 257 consecutive patients who underwent CABG between January 2001 and August 2005 at Kyungpook National University Hospital. The first 157 patients (open group) underwent conventional open harvesting of the radial artery and the second 100 (endoscopic group) had endoscopic harvesting. The severity of both the motor and sensory symptoms, as well as the cosmetic results, was evaluated immediately and at least 6 months after surgery. In the open group, 29 patients experienced neuralgia along the distribution of the lateral antebrachial cutaneous nerve, but none in the endoscopic group patients experienced any sensory abnormalities (p<0.05). However, neuralgia along the distribution of the superficial radial nerve was similarly observed in both groups. No one in either group complained of any motor symptoms. The patients in the endoscopic group were also satisfied with the cosmetic results. Conclusions ERH resulted in less neurologic complications of the hand and forearm, and outstanding aesthetics. ERH may be the procedure of choice for radial artery harvesting. (Circ J 2007; 71: 1511 - 1515)

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Background An association of mitral regurgitation (MR) with ischemic cardiomyopathy (I-CMP) increases the risk of heart failure and its surgical management remains controversial. Methods and Results Between July 2001 and June 2006, a total of 49 patients with I-CMP underwent surgical ventricular restoration (SVR) and coronary revascularization with or without concomitant mitral annuloplasty (MAP). The mean age was 59.8 years, and all patients had New York Heart Association (NYHA) class III or IV heart failure (mean left ventricular ejection fraction (LVEF) = 24.8%). Nineteen patients had MR >grade 3 (MR group). SVR and coronary artery bypass grafting were performed in all patients, and concomitant MAP was performed in the MR group. Echocardiography was performed preoperatively, postoperatively, and at mean of 19 months after operation. Preoperative left ventricular (LV) end-diastolic and end-systolic dimensions, left atrial volume index, and MR grade were statistically significantly increased in the MR group. On the early postoperative echocardiogram, mean LVEF was significantly improved, with reduction of LV dimensions, in both groups; however, at follow up, these parameters were more significantly improved in the MR group, but unchanged in non-MR group, reaching almost the same levels as the non-MR group. Conclusion In patients with I-CMP, MR increases early and late mortality; however, after SVR and concomitant MAP, LV function seems to continuously improve with more significant reduction in the LV dimensions than in the non-MR group. (Circ J 2007; 71: 1516 - 1520)

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Background In Stanford B acute aortic dissection (AAD), medical treatment is the choice of therapy in the acute phase, however, a portion of patients experience complications caused by serious clinical outcomes including aortic rupture and abdominal visceral ischemia. The objective of this study was to determine the predictors of in-hospital events in an Asian cohort of Stanford type B AAD. Methods and Results Hospital records were queried to identify patients that met following criteria: (1) AAD presenting within 14 days of symptom onset; and (2) computed tomography (CT) confirmation of a dissected descending aorta not involving the ascending aorta. An in-hospital event was defined as death, rupture/impending rupture, or organ malperfusion. Patient characteristics, inflammatory markers, and CT findings were obtained from clinical case records and retrospectively analyzed. Two hundred and twenty patients with Stanford B AAD were identified. In-hospital events occurred in 15 patients (there were 8 deaths, and 5 patients need to undergo emergent surgery because of impending rupture or rupture, and 4 patients experienced organ malperfusion). In univariate logistic regression analysis, the non-thrombosed type (odds ratio (OR) 3.88, 95% confidence interval (CI) 1.20-12.61, p=0.02) and maximum aortic diameter measured by an initial CT (each having a 5 mm increment: OR 1.61, 95% CI 1.20-2.15, p=0.001) were significant predictors of in-hospital events. In multiple logistic regression analysis, the only significant predictor was maximum aortic diameter measured by an initial CT (each having a 5 mm increment: OR 1.41, 95% CI 1.04-1.92, p=0.03). Conclusion The results identified a large maximum aortic diameter as the independent predictor of in-hospital events in Stanford type B AAD. The non-thrombosed type might also help differentiate high-risk patients. (Circ J 2007; 71: 1521 - 1524)

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Background It remains unclear whether sirolimus-eluting stents (SES) have an advantage over bare metal stents (BMS) in patients on dialysis. Methods and Results Percutaneous coronary intervention (PCI) using SES was performed in 54 dialysis patients with 69 lesions. A control group for comparison comprised 54 consecutive dialysis patients with 58 lesions who underwent PCI using BMS. Angiographic and clinical follow-ups were scheduled at 9 months. After the procedure, minimum lumen diameter (MLD) was similar between the 2 groups. At follow-up, the SES group had a higher MLD than the BMS group (1.98±0.83 mm vs 1.50±0.78 mm, p<0.01). In-stent restenosis rate was lower in lesions treated with SES than in those with BMS (22% vs 40%, p=0.048). However, there was no significant difference between the 2 groups for in-segment restenosis (31% vs 43%, p=0.3). During follow-up, there was no significant difference in the incidence of death, myocardial infarction or target lesion revascularization (TLR) (14% vs 21%, p=0.4) between the SES and BMS groups. Conclusions In this retrospective study, SES, in comparison with BMS, reduced in-stent restenosis in patients on dialysis. However, in-segment restenosis and TLR were not statistically different between lesions treated with SES and those with BMS. (Circ J 2007; 71: 1525 - 1529)

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Background Most studies have shown that early post-infarction angina (EPA) implies an unfavorable long-term prognosis among patients with acute myocardial infarction (AMI). However, some studies have failed to establish a link between the occurrence of EPA and increased mortality and recurrent infarction rates. Methods and Results In order to evaluate a long-term prognosis in patients with EPA, we assessed the 5-year prognosis of 80 patients with AMI by the presence or absence of EPA. During the 5-year follow up, the occurrence of death, cardiac death, recurrent infarction, unstable angina, heart failure, revascularization and cardiac events were recorded. A cardiac event was defined as an occurrence of any of the following events: cardiac death, recurrent infarction, unstable angina, heart failure and revascularization. Survival analysis showed no differences between patients with and without EPA in the probability of death (p=NS), cardiac death (p=NS), recurrent myocardial infarction (p=NS) and unstable angina (p=NS). Patients with EPA had a higher probability of developing cardiac events (p=0.0285) and undergoing revascularization procedures (p=0.0188). Conclusions EPA increases the risk of patients developing cardiac events and undergoing revascularization procedures, and thereby implies a poor long-term prognosis for patients with AMI. (Circ J 2007; 71: 1530 - 1533)

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Background Idiopathic restrictive cardiomyopathy (RCM) is not a single disease and is rare. Methods and Results The clinical features and clinical course of 12 pediatric patients with RCM seen between 1978 and 2005 were retrospectively analyzed. The age at diagnosis ranged from 4 months to 12 years (median 4 years). The age of 7 patients diagnosed because of an abnormal electrocardiogram (ECG) ranged from 4 to 12 years. Three infants less than 2 years old presented with cardiomegaly. Obliquely elevated ST-T segments and the late peak T waves on 12-lead ECG were present in 8 patients (67%). Three patients with ST depression during exercise had no perfusion defects on radioisotope myocardial perfusion imaging. Two patients underwent orthotopic heart transplantation. Of the remaining 10 patients, 7 have died: 4 died suddenly and 3 died of right heart failure. Three patients with a hypertrophic left ventricular wall had a prolonged survival. The probability of survival at 1, 2 and 3 years was 78%, 52% and 26%, respectively. Conclusions Obliquely elevated ST-T segments and the late peak T wave on ECG are characteristic, and reflect the restrictive physiology, which may indicate abnormalities of repolarization of ventricular muscle. The mode of death was either heart failure from pulmonary hypertension or sudden death from presumed ventricular arrhythmia. (Circ J 2007; 71: 1534 -1539)

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Background Cibenzoline is able to improve left ventricular (LV) diastolic dysfunction in patients with hypertrophic cardiomyopathy (HCM), but the exact mechanism remains to be determined. Methods and Results The present study was designed to elucidate the effect of intravenous administration of 1.4 mg/kg of cibenzoline on aortic and LV pressures, and transmitral Doppler flow pattern in 7 patients with hypertrophic obstructive cardiomyopathy (HOCM) and 9 patients with hypertrophic nonobstructive cardiomyopathy (HNCM). Before and at the end of the administration, aortic and LV pressures, LV pressure gradient (LVPG) and transmitral Doppler velocity profiles were examined. After the administration of cibenzoline, LV minimal and end-diastolic pressures decreased from 9±4 mmHg to 1±5 mmHg (p=0.0049) and from 22±7 mmHg to 14±5 mmHg (p=0.0106) in patients with HOCM, and from 9±5 mmHg to 5±3 mmHg (p=0.0036) and from 20±6 mmHg to 14±3 mmHg (p=0.0033) in patients with HNCM. LVPG decreased in all patients with HOCM. E-wave velocity increased, A-wave velocity decreased, and thus the E/A ratio increased from 0.77±0.29 to 1.20±0.48 (p=0.0004). Conclusions Reduction of LV diastolic pressures by intravenous administration of cibenzoline may be related to an improvement in the E/A ratio in patients with HCM. (Circ J 2007; 71: 1540 - 1544)

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Background The myeloid-related protein complex (MRP8/14) is expressed in activated human macrophages and reported to be involved in the inflammatory process. The expression of MRP8/14 in patients with cardiac sarcoidosis and idiopathic dilated cardiomyopathy (DCM) was investigated. Methods and Results Serum MRP8/14 levels were measured in 35 patients with sarcoidosis and 23 patients with DCM. Sera from 30 normal volunteers served as controls. Additionally, the expression profiles of MRP8/14 in the myocardium from 12 patients with active cardiac sarcoidosis and 10 DCM patients were examined immunohistochemically. Serum MRP8/14 levels were significantly higher in patients with sarcoidosis than in normal controls [515±549 (SD) ng/ml vs 230±115 ng/ml, p=0.0019]. In the sarcoidosis group, serum MRP8/14 levels in patients with definite cardiac involvement (n=10) were significantly higher than in those without (n=25) (974±878 ng/ml vs 332±204 ng/ml, p=0.0227) and they were also higher than in DCM patients (vs 252±108 ng/ml, p=0.0026). Immunohistochemically, MRP8/14 was specifically positive in the cytoplasm of macrophages and multinucleated giant cells in the myocardial granulomas. Conclusions MRP8/14 may be involved in the pathogenesis of sarcoid granulomas. The measurement of serum MRP8/14 levels is useful for the diagnosis of sarcoidosis, and their higher levels suggest the cardiac involvement. (Circ J 2007; 71: 1545 - 1550)

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Background The purpose of this study was to determine the appropriate recommendations for weaning off cardiopulmonary support (CPS) in children with fulminant myocarditis. Methods and Results Four consecutive patients diagnosed with fulminant myocarditis who were treated with CPS were enrolled (mean age: 9 years). The relationships between timing of weaning from CPS and various factors, including bleeding episodes, platelet count, serum concentration of the MB isoform of creatine kinase (CK-MB), echocardiographic findings, and the mixed venous blood oxygen saturation (SvO₂), were retrospectively analyzed. All patients had CPS performed safely for a mean duration of 53.1 h without exchange of the circuit. Three of the 4 patients had a bleeding episode before discontinuation. The minimum platelet count occurred during weaning in all 4 patients. The peak serum CK-MB concentration when initiating CPS was higher than the peak value on the day of weaning. Echocardiographic findings before stopping CPS were similar to those after weaning. The SvO₂ was 62.5% when initiating CPS and 71.3% before weaning. Conclusions In children with fulminant myocarditis CPS can be used without exchanging the circuit and can be discontinued before bleeding episodes become symptomatic, with improvement in the biomarkers and SvO₂ on weaning off CPS. (Circ J 2007; 71: 1551 - 1554)

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Background Osteoporosis and endothelial dysfunction have been associated with atherosclerosis. The correlation between brachial arterial endothelial function and lumbar spine bone mineral density (BMD) in postmenopausal women will be investigated. Methods and Results The endothelial function in 85 postmenopausal women, including 28 women with normal spinal BMD, 27 women with osteopenia, and 30 women with osteoporosis were studied. Brachial arterial flow-mediated vasodilatation (FMD) after reactive hyperemia was assessed by ultrasonography. The BMD at the lumbar spine (lumbar 2 to 4 vertebrae) was measured by dual-energy X-ray absorptiometry. Age, years since menopause, and FMD were significantly greater in the osteoporosis group than in the normal BMD group (p<0.01, p<0.05, and p<0.05, respectively). The BMD was significantly lower in the osteoporosis group than in the osteoporosis or normal BMD group (both p<0.01). After adjusting for age and years since menopause, women with osteoporosis had significantly lesser FMD than those with normal BMD (p<0.05). The univariate linear regression analysis revealed that brachial arterial FMD was significantly positively correlated with BMD (r=0.31, p<0.01), but showed no significant association with other clinical variables. In multivariate regression analysis, the FMD was significantly positively correlated with BMD (p<0.01), but not with other variables. Conclusions Postmenopausal women with osteoporosis might have impaired brachial arterial endothelial function, suggesting that brachial artery endothelial function might be associated with lumbar spine bone mass in postmenopausal women. (Circ J 2007; 71: 1555 - 1559)

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Background Because the arterial/alveolar oxygen tension ratio (a/APO2) is relatively constant throughout the entire range of fractional inspired oxygen concentration (FiO2), its use in determining the prognosis of acute pulmonary embolism (APE) was investigated. Methods and Results This study retrospectively assessed 202 consecutive patients with APE confirmed by computed tomography or high probability lung scintigraphy. All patients underwent initial arterial blood gas analysis during the first 24 h of admission. Receiver-operating characteristic analyses were performed to determine the a/APO2 cut-off value for predicting 30-day death or 30-day composite events. Cut-off values for a/APO2 were used to determine stability in all patients and 2 subgroups (0.49 for all patients; 0.49 for FiO2 =0.21; 0.46 for FiO2 >0.21). Using the cut-off value of a/APO2 <0.49 for predicting 30-day death, the negative predictive value (NPV) was 90%, and the positive predictive value (PPV) was 30.3%. For the 30-day composite end point, the NPV was 81.3%, and the PPV was 40.9%. Excluding massive APE, the a/APO2 also had high NPV and moderate PPV in predicting short-term prognosis. This study additionally demonstrated a linear relationship between platelet count and a/APO2. Conclusions The cut-off value of a/APO2 <0.49 exhibits stability at variable FiO2 values and is a useful prognostic predictor in APE. (Circ J 2007; 71: 1560 - 1566)

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Background Higher serum gamma-glutamyltransferase (GGT) levels, a marker of oxidative stress, are implicated in the development and progression of hypertension; however, data from non-Caucasian ethnicities are limited. Also, currently there is little data available on the association between serum GGT level and clinically relevant blood pressure (BP) categories earlier in the disease continuum, when hypertension prevention efforts may be applicable. The association between serum GGT and prehypertension was examined in a nationally representative sample of US adults. Methods and Results Cross-sectional study among 5,827 National Health and Nutrition Examination Survey 1999-2002 participants aged ≥18 years without cardiovascular disease (CVD) and hypertension. The main outcome-of-interest was the presence of prehypertension (systolic BP 120-139 mmHg or diastolic BP 80-89 mmHg) (n=2,269). Higher serum GGT levels were positively associated with prehypertension, independent of smoking, waist circumference, diabetes, cholesterol levels and other confounders. The multivariable odds ratio (95% confidence intervals) comparing quartile 4 of GGT (>29 U/L) to quartile 1 (<13 U/L) was 1.84 (1.37-2.46), p<0.0001. This association persisted in separate analyses among men and women. The results were consistent in subgroup analyses by race-ethnicity, age, smoking, alcohol intake, body mass index, waist circumference and diabetes. In non-parametric models, the positive association between serum GGT and prehypertension appeared to be present across the full range of GGT, without any threshold effect. Conclusions Higher serum GGT levels are associated with prehypertension in a nationally representative sample of US adults, free of CVD and hypertension. (Circ J 2007; 71: 1567 - 1572)

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Background Serum fibrin-monomer (FM) is a precursor of stable fibrin, and is a sensitive marker of a systemic hypercoagulable state. It has been reported that, in patients with acute ischemic stroke, higher levels of serum FM reflect intracardiac thrombus formation. Methods and Results Serum coagulation and fibrinolytic activity were measured in 113 patients with acute ischemic stroke within 7 (6±1) days after onset. The patients were followed for a mean of 354 (range 36-585) days. The primary endpoints were ischemic stroke recurrence with/without death. FM was markedly higher in the 19 cases with stroke recurrence (49.6±53.6 μg/ml) than in the 94 patients without stroke recurrence (14.6±30.5 μg/ml; p=0.008). The cerebrovascular event rates were markedly higher in the 12 cases with FM ≥16.5 μg/ml (37.5%) than in the 7 cases with FM <16.5 μg/ml (8.6%; p<0.001). Cox proportional hazards multivariate analysis showed that the FM level was an independent predictor of ischemic stroke recurrence with/without death (hazard ratio, 1.516 per + 1 standard deviation increase; 95% confidence interval, 1.042-2.180; p=0.036). Conclusions Elevated serum FM levels in hospitalized ischemic stroke patients may be associated with a persistent systemic hypercoagulable state and high long-term rates of cerebrovascular events. (Circ J 2007; 71: 1573 - 1579)

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Background The prognostic value of rest ²⁰¹Tl/stress ^99mTc-tetrofosmin myocardial perfusion single-photon emission computed tomography (SPECT) for the prediction of future hard cardiac events, including acute myocardial infarction (AMI), unstable angina (UAP) and cardiac death, and the implications for risk stratification has not yet been defined in a Japanese population. Methods and Results The 1,988 patients who underwent rest ²⁰¹Tl/stress ^99mTc-tetrofosmin SPECT were identified and followed up for the occurrence of AMI, UAP and cardiac death. The mean follow-up interval was 26.9±15.8 months. The 142 patients were revascularized within 60 days after SPECT and they were censored from the prognostic analysis. Summed stress score (SSS), summed rest score and summed difference score (SDS) were calculated using a 5-point scoring (Normal: 0, No uptake: 4) and a 20-segment model; 22 cases of myocardial infarction, 31 of UAP and 22 cardiac deaths occurred (1.2%, 1.7% and 1.2%, respectively). Multivariate Cox regression analysis showed that hypertension (Wald 6.37, p<0.05) and SDS (Wald 8.77, p<0.01) were independent predictors of AMI and UAP. Advanced age (Wald 16.0, p<0.001), SSS (Wald 10.9, p<0.01) and SDS (Wald 4.58, p<0.05) were independent predictors of cardiac death. Conclusion Myocardial perfusion SPECT yields prognostic information toward the identification of acute coronary syndrome and cardiac death. (Circ J 2007; 71: 1580 - 1585)

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Background Magnetocardiography (MCG) is sensitive to minute cardiac electric abnormalities, but its clinical utility in diagnosing ischemic heart disease (IHD) has not been established. The present study examined the usefulness of an integral MCG value of ventricular repolarization in patients with IHD. Methods and Results MCG was performed at rest in 14 patients with coronary stenosis >75% confirmed by coronary angiography (IHD group) using a 64-channel system, and then the sum of the 64-channel integral values of the QRS or JT intervals (QRSi and JTi, respectively) was calculated. The JTi/QRSi value indicated the total power of currents in JT compared with those in QRS. These measurements were repeated within 2 weeks after coronary revascularization. The Control group comprised 30 healthy volunteers. The baseline value of JTi/QRSi was significantly smaller in the IHD than in the Control group, but after revascularization it increased and did not significantly differ from the Control group. No significant difference in ST deviation was identified by electrocardiography (ECG) before and after coronary revascularization. Analysis of the Control group revealed that JTi/QRSi was not affected by age. Conclusions The JTi/QRSi of the MCG is more sensitive to coronary stenosis than ECG, and this parameter improves soon after coronary revascularization. (Circ J 2007; 71: 1586 - 1592)

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Background Recent advancements in 16-slice multidetector-row computed tomography (16-slice MDCT) provide for non-invasive assessment of not only coronary artery disease (CAD), but also myocardial properties and the anatomy of the whole heart. The purpose of the present study was to investigate whether the aortic valve area (AVA) in patients with aortic stenosis (AS) assessed by 16-slice MDCT corresponds to echocardiographic assessment and to evaluate simultaneously the clinical accuracy in detecting CAD with 16-slice MDCT. Methods and Results The AVA of 29 consecutive AS patients with transthoracic echocardiography (TTE) and 16-slice MDCT were analyzed. The AVA was estimated by means of the continuity equation method in 2-dimensional echocardiography (DE) and the quantitative planimetric method after multi-planar reformation in 16-slice MDCT. Concomitantly, the severity of the coronary artery stenosis was assessed by 16-slice MDCT. In the present study, the AVA assessed by TTE and 16-slice MDCT was 1.34±0.32 cm² and 1.38±0.32 cm², respectively. Regression analysis showed that the AVA in patients with AS determined by 16-slice MDCT correlated well with those determined by 2-DE (r=0.96, p<0.001). Significant coronary artery stenosis of more than 50% diameter reduction was present in 48% of the study population. Conclusions In patients with AS, the analysis of the severity of the AVA by 16-slice MDCT provides a feasible and accurate estimation with the concomitant evaluation of CAD. (Circ J 2007; 71: 1593 - 1598)

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Background The optimal left ventricle (LV) pacing site for cardiac resynchronization therapy (CRT) has been investigated, but less is known about the optimal site in the right ventricle (RV). The present study examined whether electrical resynchronization guided by electroanatomical mapping (CARTO) results in mechanical resynchronization. Methods and Results The study group included 13 patients indicated for CRT: 10 with nonischemic cardiomyopathy, 2 with ischemic cardiomyopathy and 1 with cardiac sarcoidosis, (mean LV ejection fraction: 32±10%). CARTO of the RV septum was performed to identify the site with the most delayed conduction time during LV pacing. Hemodynamic measurements were performed during conventional biventricular pacing with the RV apex and LV (C-BVP) and during biventricular pacing with the most delayed site of the RV (d-RV) and LV (D-BVP). Lead placement at 15 coronary sinus veins was examined in the 13 patients. During pacing from anterolateral veins (n=2), the d-RV was the RV apex (RVA) in 1 patient and the mid-septum in the other. During pacing from lateral veins (n=9), the d-RV comprised the RVA (n=3), the mid-septum (n=5), and the right ventricular outflow tract (RVOT) (n=1). During pacing from the posterolateral veins (n=3), the d-RV was the RVOT in all cases. In 11 of 15 sites, d-RV differed from conventional RVA. Compared with C-BVP, D-BVP produced a significant improvement in LV dp/dt. Furthermore, RV mid-septum and LV pacing markedly increased LV dp/dt and pulse pressure (PP), but RVOT and LV pacing did not. D-BVP vs C-BVP: %LV dp/dt 30±20 and 15±15%, p<0.05; RV mid-septum and LV pacing vs C-BVP: %LV dp/dt 35±20 and 10±15%, p<0.02, and vs PP 33±20 and 10±29 mmHg, p<0.02. Conclusions For pacing from the LV lateral vein, potential improvement of cardiac performance compared with that by conventional RVA placement may be realized with concomitant pacing from the d-RV (mid-septum). (Circ J 2007; 71: 1599 - 1605)

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Background This study was performed to investigate the frequency and importance of supraventricular arrhythmia and sinus node (SN) dysfunction in patients with catecholaminergic polymorphic ventricular tachycardia (CPVT). Methods and Results Eight patients with CPVT (mean age: 16.8±8.1 years) underwent an electrophysiological study. SN recovery time (1,389±394 ms) was slightly prolonged, and 4 of 8 patients had abnormal values. Atrial flutter (AF) was induced by low-rate atrial pacing in 2 patients and by isoproterenol infusion in 1 patient. Atrial fibrillation (Af) was induced by isoproterenol infusion in 2 patients. One patient presented with Af during the follow-up period, and 2 of 4 patients with AF/Af presented with increased SN recovery time. Conclusions Patients with CPVT frequently have associated with SN dysfunction, and inducible atrial tachyarrhythmias, which indicate that the pathogenesis of CPVT is limited not only to the ventricular myocardium, but also to broad regions of the heart, including the SN and atrial muscle. (Circ J 2007; 71: 1606 - 1609)

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Background Amiodarone-induced pulmonary toxicity (APT) is the most serious side-effect of amiodarone, and its detection and prevention are extremely important. This study was designed to evaluate the incidence and clinical risk factors of APT, and the utility of a pulmonary function test or serum KL-6 assay to predict pulmonary toxicity in Japanese patients receiving low-dose amiodarone. Methods and Results Five hundred consecutive patients receiving amiodarone were retrospectively evaluated. Mean follow-up period was 48 months and mean maintenance dose was 141 mg daily. Cumulative incidence of APT was 4.2%, 7.8%, and 10.6% at 1, 3, and 5 years, respectively. On multivariate analysis, age at the start (hazard ratio (HR) =1.48, 95% confidence interval (CI) 1.13 to 1.93) was a significant pretreatment risk factor. Age (HR =1.64, 95% CI 1.29 to 2.09), maintenance dose (HR =1.90, 95% CI 1.45 to 2.49) and plasma monodesethylamiodarone concentration (HR =1.30, 95%CI 1.08 to 1.58) were risk factors. Sensitivity and specificity in screening with measurement of percent predicted diffusion capacity of carbon monoxide, ≥15% individual decrease, were 68% and 69%, and for ≥20% individual decrease, were 59% and 74%, whereas those in screening with serum KL-6 assay, ≥500 U/ml, were 25% and 91%, respectively. Conclusions Even at low dose, amiodarone shows substantial pulmonary toxicity. Higher age and higher maintenance dose are risk factors. Further decreasing the maintenance dose of amiodarone should be considered in order to reduce the incidence of pulmonary toxicity, at least in Japanese patients. (Circ J 2007; 71: 1610 - 1616)

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Background The purpose of this registration is to follow incidence and case fatality trend of acute myocardial infarction (AMI) in Japan, using a whole community population disease registry that surveys the most up-to-date information. Since the 1970s, mortality from coronary heart disease has followed a declining trend in Japan, which has been attributed to a decrease in the incidence of AMI and some evidence suggests that incidence has leveled off during the past couple of decades. These reported decreasing or stable trends in AMI have been observed despite recent worsening of the cardiovascular risk factor situation in Japan (Japanese paradox). Therefore, monitoring the disease course of AMI is of immense importance. Methods and Results The Takashima AMI Registry established in 1988 covers a stable population of approximately 55,000 in Takashima County in central Japan. Registered patients included all Takashima County residents who have been diagnosed with AMI. The criteria of AMI are in accord with those of the World Health Organization's Monitoring of Trends and Determinants in Cardiovascular Disease (WHO-MONICA) project. Conclusion Comprehensive disease registry data is especially appropriate for determining the incidence as well as the trend of diseases such as AMI. This registration study covering an entire community will enable researchers to follow trends in AMI incidence with a high degree of precision. (Circ J 2007; 71: 1617 - 1621)

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Background Statins reportedly protect against myocardial infarction, but the precise mechanism is unclear. Methods and Results Rabbits underwent 30 min of coronary occlusion followed by 48 h of reperfusion. Pravastatin (1 or 5 mg/kg) or saline was intravenously administered 10 min before ischemia. Pravastatin (5 mg/kg) was also administered 10 min before reperfusion. N^ω-nitro-L-arginine methylester (L-NAME, 10 mg/kg), chelerythrine (5 mg/kg) or 5-hydroxydecanoic acid sodium salt (5-HD, 5 mg/kg) was intravenously administered 10 min before pravastatin injection. The infarct size was determined. The myocardial interstitial levels of 2,5-dihydroxybenzoic acid (DHBA) and nitrogen oxide (NOx), and the intensity of myocardial dihydroethidium staining were measured. Pre-ischemic treatment with pravastatin reduced the infarct size (34±5% and 24±4%, 1 and 5 mg/kg, respectively), but not pre-reperfusion treatment (42.1±3.7%), compared with the control (45±3%). This effect was blocked by L-NAME (42.6±4%), chelerythrine (50.9±3%) and 5-HD (52.7±2%). Pre-ischemic treatment with pravastatin increased myocardial NOx levels, and attenuated both the 2,5-DHBA level and the intensity of dihydroethidium staining during reperfusion. Chelerythrine abolished the increase in NOx levels by pravastatin. Conclusion Pre-ischemic treatment with pravastatin reduces the myocardial infarct size via protein kinase C-dependent nitric oxide production, decreasing hydroxyl radicals and superoxide, and opening the mitochondrial adenosine triphosphate-sensitive potassium channels. (Circ J 2007; 71: 1622 - 1628)

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Background Continuous rapid atrial stimulation causes atrial remodeling, but little is known about the difference in the arrhythmogenicity of the left (LA) and right atria (RA). Methods and Results In 14 beagle dogs, continuous rapid pacing (400 beats/min) was delivered from the right (n=7) or left (n=7) atrial appendage (RAA or LAA) for 2 weeks. The atrial effective refractory period (ERP), ERP dispersion, and inducibility of atrial fibrillation (AF) were evaluated along the time course from 4 atrial sites: (1) RAA, (2) area close to the inferior vena cava (IVC), (3) Bachmann's bundle (BB) and (4) LA. The ERP exhibited progressive shortening at all sites, but the degree of shortening differed among them. In the RA stimulation group, ERP shortening was more prominent in the RAA and LA than in the IVC or BB. In contrast, in the LA stimulation group, ERP shortening was more prominent in the LA than in the other sites. As a result, ERP dispersion was larger in the LA stimulation group than in the RA stimulation group and the AF inducibility was higher in the LA stimulation group than in the RA stimulation group, especially at the LA site (p<0.05). Conclusion LAA stimulation was more arrhythmogenic than RAA stimulation in this model. This result may partly explain the importance of premature contractions occurring from the pulmonary veins in clinical cases of AF. (Circ J 2007; 71: 1629 - 1635)

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Background Chronic left atrial dilatation (CDLA) is associated with an increased incidence of atrial fibrillation (AF). The electrophysiological functions of the left atrial posterior wall (LAPW) are not well understood. Methods and Results Eight control dogs and 8 with CDLA (developed 6 months after partial mitral valve avulsion) were studied. An electrophysiological study was performed using the noncontact mapping system. The conduction velocity was significantly decreased in the LAPW in the CDLA group. During atrial extrastimulation, a sharp curvature in the activation wavefront became apparent in the LAPW of 6 CDLA dogs, with unidirectional block in 1 dog. The effective refractory periods increased homogeneously throughout the atrium in the CDLA group. AF was much more easily inducible in the CDLA dogs than in the controls. After the onset of AF, the LAPW exhibited the earliest disorganized activity as compared with other sites in the left atrial. In the CDLA dogs, the most extensive interstitial fibrosis was observed in the LAPW. Conclusions Alterations in the electrophysiologic properties and tissue structure of the LAPW were observed in the CDLA dogs. This study supports the idea that the LAPW may play a role in the mechanism of AF induced by CDLA. (Circ J 2007; 71: 1636 - 1642)

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Background Although sonothrombolysis has been studied for development of recanalization that is safer and more efficacious than the methods currently used, there have been no studies of the efficacy of sonothrombolysis for the platelet-rich thrombi that typically cause acute myocardial infarction (AMI). The effects of adding ultrasound (US) to pharmacological lysis of platelet-rich thrombi was examined in a rabbit model of femoral artery occlusion. Methods and Results In 35 rabbits, the right femoral artery was balloon-injured repeatedly at 4-week intervals to induce platelet-rich thrombi. Two hours after the induction of occlusive thrombi, 27,500 IU/kg tissue plasminogen activator (tPA) were injected via an ear vein, with or without transcutaneous US (continuous wave, 1 MHz, 0.75 W/cm²), or 13,750 IU/kg tPA was administered with US (n=10). Significantly higher rates of successful thrombolysis (Thrombolysis In Myocardial Infarction grade 3) were observed with US (90.0%) than without it (10.0%), irrespective of the dose of tPA used (p<0.01). The peak flow velocity in affected femoral arteries was significantly higher with US (p<0.01), and histological examination confirmed complete dissolution of thrombi. However, the thrombi were not affected by US alone (n=5). Conclusions US facilitates thrombolysis of platelet-rich thrombi and could be a useful component of thrombolytic therapy following AMI. (Circ J 2007; 71: 1643 - 1648)

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Background Neointimal development is seen clinically after both vein grafting and balloon catheterization, but may not represent the same pathology under these 2 conditions. This study compared the degree of neointimal hyperplasia after vein grafting or arterial-injury grafts in 2 strains of mice: C57Bl/6 and FVB. Methods and Results Jugular vein branches were interpositioned as grafts in the femoral artery of syngenic-matched mice, with graft harvest at 30 days. Wire-injured carotid arteries were grafted to the carotid arteries of syngenic-matched mice, with graft harvest at 14 days. Histomorphometry revealed no strain differences in vein grafts in the extent of position-dependent neointimal thickening or lumen cross-sectional area. Both strains showed significantly thicker neointima and less lumen area at the proximal graft site (vs the mid-graft; p<0.05). In contrast, a significantly greater neointimal thickness was found in the wire-injured carotid grafts of FVB mice vs those of C57Bl/6 mice (p<0.05). Conclusions Neointimal formation shows a vessel-dependent, strain-dependent difference, with greater arterial neointimal thickening in FVB mice. These data suggest that different mechanisms operate for arterial-injury- vs vein-graft-associated neointimal development and that the difference has a genetic basis. (Circ J 2007; 71: 1649 - 1652)

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Left ventricular hypertrophy (LVH) is primarily or secondarily caused by a cardiovascular or systemic disease. The pattern of LVH is distinctive in hypertrophic or metabolic cardiomyopathy and differs from that seen in LVH caused by hypertension or aortic stenosis. A 42-year-old Japanese man had LVH similar to that with hypertrophic cardiomyopathy. The patient was diagnosed with glycogen storage disease type IIIa (GSD-IIIa). Echocardiography showed that he had severe LVH, and concomitant hepatomegaly and hypoglycemia, which led to measurement of glycogen debranching enzyme (GDE) activity; it was undetectable. Sequence analysis of the AGL gene encoding GDE showed a novel nonsense mutation: a C-to-T transition at codon 285 in exon 8, resulting in substitution of the arginine codon by the stop codon (R285X). The patient was homozygous for the mutation. Cardiomyopathy in this patient was caused by a nonsense mutation in the AGL gene. Five other Japanese GSD-IIIa patients over 30 years of age have all presented with cardiomyopathy, as well as hepatomegaly and hypoglycemia. Patients with LVH associated with hepatomegaly and hypoglycemia should undergo biochemical and genetic analyses for GSD-IIIa. (Circ J 2007; 71: 1653 - 1656)

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The pitfall of percutaneous cardiopulmonary support (PCPS), which is thought to be useful for the detection of massive pulmonary emboli in patients, was investigated. A case of massive pulmonary embolism occurring 9 days after repair of the left Achilles tendon in a 31-year-old woman is described. Preoperatively, the thrombi in the right atrium and between the left popliteal vein and soleus muscle vein, as well as a massive pulmonary emboli, were detected. Despite using PCPS, it was difficult to maintain arterial pressure because of the outflow cannular occlusion caused by the floating thrombus in the right atrium, and so therefore the patient became hemodynamically unstable. After the removal of the thrombus and after a cardiopulmonary bypass was established, a pulmonary embolectomy was performed. (Circ J 2007; 71: 1657 - 1658)

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Malignant fibrous histiocytoma of the thoracic aorta associated with ulcer-like projection has not been reported previously. The hypovascular tumor of the thoracic aorta involved the mural layer, which showed intra- and extra-mural growth patterns and no significant filling defect within the aortic lumen, and mimicked ulcer-like projection with secondary pseudoaneurysm formation. Aortic tumor, although rare, should be included among the causes of an ulcer-like projection. (Circ J 2007; 71: 1659 - 1661)

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