Background In Western countries, the length of hospital stay after acute myocardial infarction (AMI) has decreased dramatically during the past 3 decades and is now approximately 1 week. However, epidemiological data concerning the length of hospital stay, its predictors and trends based on a large-scale sample are still limited in Japan. Methods and Results The study group comprised 4,113 surviving AMI patients who were enrolled in the Osaka Acute Coronary Insufficiency Study from April 1998 to March 2003. The mean length of hospital stay was 31.2 days. Clinical factors (patient characteristics, severity of infarction, therapy, and in-hospital complications) only explained 26% of the variation in hospital stay. The mean hospital stay was significantly longer in 1998 than in 2002. In 2002, occupational status and admission to a high-volume hospital were independent predictors of a shorter hospital stay, but this association was not observed in 1998. Conclusions The hospital stay is still extremely long in Japan and clinical factors do not provide an explanation. The findings of the present study suggest that the hospital stay could be reduced in some patients with AMI, but randomized studies are needed to examine the feasibility of early discharge. (Circ J 2004; 68: 809 - 815)

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Background There are few reports that examine the current imaging and management techniques according to the severity of acute pulmonary embolism (APE) or that clarify whether the management strategy ameliorated the mortality from APE. Methods and Results The study group were 456 patients with APE who were clinically diagnosed before their death. The severity at diagnosis, and the imaging and management techniques were analyzed. Mortality from APE was 0.8% in patients without shock nor right ventricular overload, 2.7% in patients with right ventricular overload without shock, 15.6% in patients with shock, and 52.4% in patients with cardiopulmonary arrest (p<0.0001). In the more severe cases, pulmonary angiography and trans-thoracic echocardiography were used more frequently, whereas both ventilation and perfusion lung scans were used less frequently. Computed tomography was used widely, regardless of the severity. Thrombolytic therapy and catheter therapy were used more frequently in the more severe cases, but an inferior vena cava filter was the only management strategy that reduced the mortality from APE. Conclusions The severity of APE at diagnosis affected the selection of both the diagnostic techniques and the type of management. Implantation of inferior vena cava filters reduced the mortality from APE. (Circ J 2004; 68: 816 - 821)

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Background Homocysteine is involved in coronary atherosclerosis through oxidative stress, so the present study investigated the association between plasma concentrations of homocysteine and extracellular superoxide dismutase (EC-SOD) in coronary artery disease (CAD). Methods and Results The study group comprised 154 consecutive male patients with suspected CAD who had undergone angiography. Plasma concentrations of homocysteine and EC-SOD, which was determined before (basal) and after heparin therapy, were measured and the difference was designated as endothelium-bound EC-SOD. The EC-SOD ratio (endothelium-bound/basal EC-SOD) was also evaluated as an index of binding capacity. The plasma homocysteine concentration in the stenosis (+) group (n=97, 12.0±4.6 μmol/L) was significantly higher than that of the stenosis (-) group (n=57, 10.2±3.0 μmol/L, p=0.004). Plasma homocysteine correlated positively with the basal EC-SOD (r=0.377, p<0.001) and negatively with the EC-SOD ratio (r=-0.199, p=0.014). When the group was subdivided according to either homocysteine or the EC-SOD ratio, there were 2 groups with high homocysteine concentration and of these atherosclerosis was reduced in the group with a high EC-SOD ratio. Conclusions In CAD patients, homocysteine is involved in the significant release of EC-SOD from the endothelium. Furthermore, the higher EC-SOD binding capacity, even at high concentrations of homocysteine, suggested that homocysteine-induced atherosclerosis was suppressed. (Circ J 2004; 68: 822 - 828)

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Background The long-term prognosis and cardiac function of fulminant myocarditis treated with percutaneous cardiopulmonary support (PCPS) was compared with the outcome of those not treated with PCPS. Methods and Results From 1991 to 2000, 14 patients with fulminant myocarditis (left ventricle ejection fraction (LVEF) ≤40%) were admitted to hospital. PCPS was necessary for treatment of shock in 8 (PCPS group), but not for the remaining 6 patients (non-PCPS group). In the PCPS group, 6 patients (75%) survived the critical phase and did not have any cardiac problems after discharge (range of follow-up period, 1.4-6.0 years). All patients in the non-PCPS group survived the acute phase; 1 patient had congestive heart failure 1.5 years after discharge, and another died from malignancy (follow-up period range, 2.2-9.4 years). Although the left ventricular ejection fraction (LVEF) of the PCPS group was significantly lower than that of the non-PCPS group in the acute phase, there was no significant difference in LVEF between the 2 groups in the chronic phase. Conclusion Patients who survive the acute phase crisis of acute myocarditis have a favorable long-term survival rate, whether or not mechanical support is used. (Circ J 2004; 68: 829 - 833)

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Background The aim of this study was to evaluate pharmacological cardioversion of long-lasting persistent atrial fibrillation (AF) using bepridil in terms of recovery of atrial mechanical function and maintenance of sinus rhythm. Bepridil alone or in combination with aprindine is effective for termination of persistent AF. Methods and Results The study group comprised 38 consecutive patients (24 men, 58.8±9.3 years) with successful conversion of persistent AF lasting >1 month either pharmacologically (Group I) or electrically (Group II). Fast Fourier transform analysis of fibrillation waves was performed and fibrillation cycle length (FCL) was calculated from the peak frequency. In Group I, sinus rhythm was pharmacologically restored in 22 patients after an average 30 days (7-49 days) of bepridil administration, either alone (11) or in combination with oral aprindine (11); they were followed up while using the same drugs. In Group II, electrical conversion restored sinus rhythm in 16 patients, and they were followed up with conventional antiarrhythmic drugs other than bepridil and aprindine. After bepridil treatment FCL increased and became significantly longer in Group I than in Group II (190±39 vs 150±29 ms, p<0.001). Atrial peak velocity in transmitral flow within the first week after cardioversion was greater in Group I than in Group II (68±35 vs 32±20 cm/s, p<0.05). By Kaplan-Meier analysis, 83% of Group I patients were free of AF recurrence at the 12-month follow-up, compared with 36% in Group II (p<0.005). Conclusions In patients with long-lasting AF, pharmacological conversion with bepridil alone or in combination with aprindine recovered atrial mechanical function better and maintained sinus rhythm longer than electrical conversion. (Circ J 2004; 68: 834 - 839)

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Background In the present study, multislice spiral computed tomography (MSCT), which allows non-invasive assessment of coronary artery plaque, was used to compare the CT density of plaque between patients with acute coronary syndrome (ACS) and those with stable angina (SA). Methods and Results MSCT was performed in 20 patients with ACS (17 with acute myocardial infarction, 3 with unstable angina) and 22 patients with SA. The presence of the plaque was defined on the basis of multiplanar reformation and axial images. At least 4 regions of interest were then placed within the plaque and the minimum CT density was measured and expressed as Hounsfield units (HU). The number of plaques did not differ between the 2 groups, but the minimum CT density was significantly lower in patients with ACS (25±15 HU) than in those with SA (71±16 HU, range 46-101 HU, p<0.001). Similarly, the minimum plaque density was significantly lower in the culprit coronary segment (26±16 HU) than in the non-culprit segment (48±17 HU) in 15 ACS patients with multiple plaques. Conclusion MSCT can potentially differentiate vulnerable from stable plaque in patients with coronary artery disease, although long-term, prospective analysis is needed to establish the conclusion. (Circ J 2004; 68: 840 - 844)

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Background Stenosis of the left internal thoracic artery (LITA) graft, which usually occurs at the site of the anastomosis, can be noninvasively evaluated by the flow pattern in the proximal graft, but the flow pattern is influenced by several other factors. Methods and Results In the present study, LITA graft flow was investigated by high-frequency transthoracic Doppler echocardiography in 75 consecutive patients who underwent postoperative angiography of the LITA graft. The flow velocity was measured at both the anastomosis and proximal to it, and compared with the quantitative angiographic results. Flow at both sites was detected in 61 (81%) of the 75 patients. The diastolic velocity ratio of the anastomosis to the proximal site correlated with the percent diameter stenosis at the anastomosis. A diastolic velocity ratio >2.0 had a high sensitivity, specificity, positive predictive value and negative predictive value for the presence of significant stenosis at the anastomosis of a LITA graft. Conclusions High-frequency transthoracic Doppler echocardiography can be used for the noninvasive diagnosis of LITA graft stenosis. (Circ J 2004; 68: 845 - 849)

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Background There may be an increased risk of pulmonary thromboembolism (PTE) with antipsychotic drugs, so this association was investigated in autopsy cases of sudden unexpected death determined by the Department of Legal Medicine of a Japanese university hospital. Methods and Results Records of 1,125 forensic autopsies (808 males, 317 females) performed during the study period for investigation of the cause of sudden unexpected death were reviewed and a logistic regression analysis was performed to explore whether age, gender, body mass index (BMI), and antipsychotic drug use were associated with fatal PTE. Among all records, 34 (3.0%; 14 males, 20 females) indicated the use of antipsychotic drugs and 28 (2.5%; 9 males, 19 females) indicated PTE as the cause of death. Of the 28 subjects who died from PTE, 8 had taken antipsychotic drugs (29%) and all were female. Female gender and antipsychotic drug use accounted for a significantly higher risk of PTE death with an odds ratio of 4.22 (95% confidence interval (CI), 1.82-9.78; p<0.01) and 10.49 (95% CI, 3.95-27.85; p<0.01), respectively. Conclusions Japanese women taking antipsychotic drugs may be at particular risk for PTE. (Circ J 2004; 68: 850 - 852)

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Background Calcium channel blockers (CCBs) may have a positive influence on the long-term prognosis of Japanese patients with ischemic heart disease. Methods and Results The effect of nifedipine-retard (NR) (n=202) compared with that of non-CCB treatment (n=92) on the secondary prevention of myocardial infarction (MI) was retrospectively investigated in patients who had survived acute MI between 1987 and 1996. The primary endpoint was the occurrence of cardiac death or non-fatal MI. The median follow-up was 6.3±2.4 years. The incidence of cardiac events was 8.9% in the NR group and 14.1% in the non-CCBs group (p=0.14, odds ratio (OR): 0.584, 95% confidence interval (CI): 0.286-1,193). However, subanalysis revealed that NR significantly reduced the incidence of cardiac events in patients aged less than 55 years (4.2 vs 18.2%, p=0.016, OR: 0.180, 95%CI: 0.045-0.721) and those who did not smoke (8.6 vs 16.4%, p=0.048, OR: 0.462, 95%CI: 0.203-0.999). Conclusion Although this was a retrospective analysis, it showed that NR did not cause an increase in the incidence of cardiac events in post-MI patients; it even prevented cardiac events, especially in those who were less than 55 years of age and in non-smokers, suggesting the potential usefulness of CCBs in the secondary prevention of MI in Japan. (Circ J 2004; 68: 853 - 859)

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Background Although cholesterol management reportedly reduces fatal and non-fatal coronary heart disease (CHD) events in subjects with or without evident atherosclerotic disease, it is still uncertain whether these benefits extend to Japanese. Methods and Results The study group comprised 8,009 subjects with mildly elevated total cholesterol who were randomized to treatment with 10-20 mg pravastatin plus diet (2,691 women, 1,267 men) or diet alone (2,758 women, 1,293 men). The groups were extremely well balanced with respect to baseline demographics and risk factors such as blood pressure and plasma lipids. Over a 5-year period of follow-up, the primary end-points will be a composite of fatal and non-fatal coronary events. Secondary end-points will include stroke and transient ischemic attack, all cardiovascular events and total mortality. Conclusions The 2 groups will be followed up until the end of March 2004 and end-points will be analyzed by full analysis set. (Circ J 2004; 68: 860 - 867)

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Background The 3-dimensional (D) structural abnormalities of the coronary capillary network and capillary volume changes after myocardial reperfusion were investigated using confocal laser scanning microscopy. Methods and Results Using open-chest anesthetized rats' hearts, the left anterior descending artery (LAD) was occluded for 7 min followed by reperfusion. The hearts were divided into 2 groups: (1) reperfused area stained well by intravenous indocyanine green after reperfusion (Reflow), and (2) lack of staining in the reperfused area (No-reflow). The entire coronary microvasculature was filled with contrast medium using a Langendorff's perfusion system. Capillaries were observed 3-dimensionally in the control and reperfused areas in both the Reflow and No-reflow group and the capillary volume fraction was computed from the 3-D images. The reperfused area in both groups showed decreased capillary diameter with waving and shrinkage configuration. In the No-reflow group, marked interruption of capillary network was observed. In the Reflow group the capillary volume fraction was significantly reduced in the reperfused area compared with the control area (14.8±4.1% vs 22.2±5.6%, p<0.05). Capillary volume fraction was further decreased in the No-reflow group compared with Reflow (5.3±1.4% vs 14.8±4.1%, p<0.01). Conclusion The morphological changes in coronary capillaries after reperfusion were characterized by waving and shrinkage, which resulted in a reduction in capillary volume. (Circ J 2004; 68: 868 - 872)

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A 25-year-old male was admitted to hospital with a 3-day history of worsening faintness. The electrocardiogram showed complete atrioventricular block. Echocardiography showed generalized hypokinesis and prominent trabeculations ranged from the apex to the mid-ventricular lateral wall of the left ventricle as well. Furthermore, trabeculations in the left ventricle were seen in his sister and brother. Thus, isolated ventricular noncompaction (IVNC) was diagnosed and a permanent pacemaker was implanted. Common clinical symptoms of IVNC are heart failure, ventricular arrhythmias, and embolic events. This is the first reported adult case of IVNC disclosed by the presence of complete atrioventricular block. (Circ J 2004; 68: 873 - 875)

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A 56 year-old man was referred to hospital for evaluation of syncopal episodes. During head-up tilt testing, his symptom was reproduced, associated with bradycardia and hypotension, by a low dose of isoproterenol (0.02 μg · kg ^-1 · min^-1) infusion in the supine position before tilting-up. Isoproterenol infusion can provoke a vasovagal response without tilting. Careful observation of the patient's hemodynamics is mandatory not only during tilting, but also in the supine position before tilting-up. (Circ J 2004; 68: 876 - 877)

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A 57-year-old man was admitted with dyspnea. Clinical evaluation revealed atrial fibrillation and congestive heart failure (CHF). Standard medical therapy of CHF failed to completely improve the dyspnea and polysomnography revealed Cheyne-Stokes respiration with central sleep apnea (CSR-CSA). He was equipped with noninvasive positive pressure ventilation (NPPV) with bilevel positive airway pressure (BiPAP). The combined therapy of medical treatment of the CHF and administration of NPPV with BiPAP reduced the CSR-CSA. This regimen resulted in marked improvement of cardiac function, evaluated by echocardiography, and reduction of plasma concentration of brain natriuretic peptide. After the patient recovered from CHF and was discharged from hospital, he continued to use NPPV with BiPAP at home. In patients with CHF, it is important to be aware of sleep-related breathing disorders because treatment will not only improve the hypoxemia, but also the cardiac dysfunction. (Circ J 2004; 68: 878 - 882)

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This report presents the first case of an unusual biventricular myocardial infarction caused by pulmonary thromboembolism in a 55-year-old woman who had an anomalous origin of the right coronary artery (RCA) from the left coronary sinus. The RCA consequently courses between the aorta and pulmonary trunk, and dilatation of the pulmonary artery because of elevated pulmonary artery pressure compressed the proximal portion of the RCA. The consequent reduced right coronary oxygen supply and sudden increase in right ventricular afterload contributed to the characteristic right ventricular infarction, in addition to a left ventricular infero-posterior infarction. Her anginal symptoms disappeared following successful anticoagulation therapy and insertion of an inferior vena caval filter, without coronary bypass. This pathophysiologic phenomenon is rare, but can be fatal. (Circ J 2004; 68: 883 - 886)

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