Background The purpose of this study was to use a contemporary database to examine the relationship between annual hospital volume and the outcomes of percutaneous coronary interventions (PCIs) for acute myocardial infarction (AMI), given the wide spread use of coronary stents. An inverse relation exists between the number of PCIs and short-term outcome, but PCI practice has been changing with the availability of new devices such as stents. Methods and Results Data from the 1997 Japanese nationwide registry were analyzed to determine the relation between the annual hospital volume of PCI procedures for patients with AMI and in-hospital mortality, as well as the need for coronary artery bypass graft (CABG) surgery. A total of 129 hospitals (2,491 patients) were divided into terciles according to the annual volume. Of the procedures, 39% involved coronary stents. Median annual PCI volumes varied across terciles from low =10, middle =33, and high =89. After adjusting for patient characteristics, there was no significant relationship between volume and in-hospital mortality (trend P=0.66) and CABG (trend P=0.35). Among patients who received stents (n=958), there was no significant association between volume and either mortality or CABG. Conclusions Using the contemporary database, there was no significant relationship between hospital volume and in-hospital outcome among AMI patients undergoing PCIs. (Circ J 2004; 68: 887 - 891)

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Background The role of inflammation in the genesis of cardiovascular disease has attracted attention and in the present study the association among metabolic syndrome (MS), white blood cell (WBC) count, and insulin concentration was investigated. Methods and Results A cross-sectional study of 3,594 Japanese men aged 34-69 years evaluated the MS components (high blood pressure, hypo-high density lipoprotein (HDL)-cholesterolemia, hypertriglyceridemia, hyperglycemia), as defined by the criteria given in the Third Report of the National Cholesterol Education Program Expert Panel on Detection Evaluation, and Treatment of High Blood Cholesterol in Adults, except for obesity [body mass index (BMI) ≥25 kg/m²]. WBC count had a positive correlation with BMI, blood pressure, triglyceride, glucose and insulin, and a negative correlation with HDL-cholesterol. The multi-adjusted means of WBC count and insulin concentration were significantly higher in MS subjects defined as having 3 or more of the components than in non-MS subjects with no more than 2 components. Both means also increased with the number of MS components (p<0.001 for trend). In the multiple linear regression analysis, BMI, HDL-cholesterol, systolic blood pressure, glucose and triglyceride had a significant and independent association with WBC count, but the insulin concentration did not. Conclusions The cluster of MS components based on insulin resistance may cause low-grade inflammation. (Circ J 2004; 68: 892 - 897)

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Background There is some controversy about the role of insulin resistance (IR) in the regulation of blood pressure (BP). Moreover, a large study of the association between BP and IR has not been conducted in normal glucose tolerance Asians. The present study investigated the relationships between IR, body mass index (BMI) and waist circumference and BP in normoglycemic Koreans. Methods and Results Anthropometric indices of adiposity, metabolic variables (fasting serum insulin and a homeostasis model assessment (HOMA) index of insulin sensitivity), BP and several cardiovascular risk factors were measured during a cross-sectional survey of 49,076 normoglycemic Korean subjects. A high BP was defined as a systolic BP ≥140 mmHg or a diastolic BP ≥90 mmHg. The prevalence of high BP by HOMA grading was 0.985 (95% confidence interval (CI) 0.857-1.132, p=0.835), 1.180 (95% CI 1.032-1.350, p=0.016), 1.289 (95% CI 1.129-1.472, p<0.001), and 1.540 (95% CI 1.341-1.768, p<0.001) times higher in subjects in the second, third, fourth, and fifth quintiles, respectively, compared with those in the first quintile. In addition, age, sex, waist circumference and BMI were found to be significantly associated with a high BP. Conclusion IR, BMI and waist circumference are independently correlated with high BP in normoglycemic Koreans. (Circ J 2004; 68: 898 - 902)

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Background In the percutaneous coronary intervention (PCI) era, the impact of initial ST-segment elevation magnitude on left ventricular (LV) function in patients with acute myocardial infarction (AMI) remains unclear. Methods and Results In the present study, 239 patients with total occlusion and 81 patients with spontaneous reperfusion within 12 h of their first anterior AMI were evaluated. The sum of ST-segment elevation (ΣST) was measured in leads I, aV_L and V_1-6 shortly before angiography. Predischarge LV ejection fraction (LVEF) was obtained at 15±5 days. In total occlusion, the predischarge LVEF was significantly lower in patients with ΣST ≥10 mm than in those with ΣST <10 mm (51±14% vs 57±14%, p<0.01). However, in spontaneous reperfusion, there was no significant difference between patients with ST ≥10 mm and those with ΣST <10 mm (61±13 vs 62±14 %, p=NS). Predischarge LVEF significantly correlated with ΣST in total occlusion (r=-0.25, p<0.01), but not in spontaneous reperfusion (r=0.03, p=NS). Conclusion The results suggest that initial ΣST is an important predictor of LV function in patients with total occlusion, but not in those with spontaneous reperfusion. (Circ J 2004; 68: 903 -908)

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Background The prevalence and ECG characteristics of idiopathic ventricular arrhythmia originating in the free wall of the right ventricular outflow tract (RVOT) require further clarification, which was the aim of the present study of 110 patients with idiopathic ventricular tachycardia (n=34) or premature ventricular contraction (n=76; OT-VT/PVC) who underwent successful catheter ablation at the RVOT. Methods and Results Ten OT-VT/PVCs (9%) were ablated successfully at the free wall (FW-VT/PVC); the remaining 100 (91%) were ablated at the RVOT septum (Sep-VT/PVC). R wave amplitudes in the inferior leads were significantly smaller in FW-VT/PVC than in Sep-VT/PVC (p<0.01). An RR' pattern in the inferior leads was observed significantly more often in FW-VT/PVC than in Sep-VT/PVC (p<0.001). QS-wave amplitude in each of leads V₁ to V₃ was significantly deeper in FW-VT/PVC than in Sep-VT/PVC (p<0.001). ECG criteria requiring an RR' pattern in all inferior leads as well as an S-wave amplitude of at least 3.0 mV in lead V₂ differentiated FW-VT/PVC from Sep-VT/PVC with high sensitivity, specificity, and predictive accuracy. Conclusions Although FW-VT/PVC has a relatively low prevalence, it has several distinctive ECG characteristics and detailed ECG analysis can differentiate it from Sep-VT/PVC. (Circ J 2004; 68: 909 - 914)

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Background Using the exercise ECG for diagnosing coronary artery disease (CAD) is hampered by the occurrence of false-positive (FP) ST-segment depression. Because it is known that the recovery ST-T time-course in CAD differs from that in FP subjects, the ST slope may help discriminate FP from true-positive (TP) results. Methods and Results Treadmill digitized ECG from patients with significant ST-segment depressions and normal resting ECG were analyzed in 134 patients with CAD on angiography (>50% narrowing) and reversible perfusion defects (TP group), and 64 subjects with normal perfusion (FP group) on exercise single photon emission computed tomography. The ST slope between the J-point and J₈₀ was measured every minute up to 6-min postexercise. The ST slope was significantly higher in FP than in TP at peak exercise, and at postexercise 1-, 2- and 3-min (p<0.01, all). Thereafter, it gradually increased in TP, while monotonically decreasing in FP. Its decrease from 3- to 6-min could correctly diagnose 88% of FP subjects, whereas it was found in only 19% of TP patients (total accuracy 83%). Conclusions The ST slope change from early to late recovery is a simple yet reliable marker for discriminating FP from TP ST-segment responses in subjects with a normal resting ECG. (Circ J 2004; 68: 915 - 922)

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Background Secretion of A-type (atrial) and B-type (brain) natriuretic peptides (ANP and BNP) increases in relation to left ventricular (LV) dysfunction in patients with myocardial infarction (MI). However, it is unknown what determines the concentrations of ANP and BNP in asymptomatic MI patients with preserved LV function, so the aim of the present study was to examine if they are associated with MI size. Methods and Results Plasma concentrations of ANP and BNP in the peripheral blood were measured in 88 asymptomatic (New York Heart Association class I) patients with previous MI. The infarct size was quantitatively calculated from rest thallium-201 myocardial single photon emission computed tomography. In multivariate linear regression analysis that included MI size, hemodynamic parameters, and age as covariables, only BNP concentrations had a significant association with MI size (p=0.0001). In contrast, ANP concentrations were not significantly correlated with MI size in either the univariate or multivariate analysis. Conclusions BNP but not ANP concentrations increased in proportion to the scintigraphic MI size despite the lack of heart failure in asymptomatic patients with previous MI. Thus, the increase in plasma BNP concentrations reflects the MI size, an important determinant of prognosis, in asymptomatic patients with MI. (Circ J 2004; 68: 923 - 927)

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Background This study aimed to clarify the effect of intracoronary administration of combined adenosine and nicorandil on the no-reflow phenomenon. Methods and Results Fifty patients (67±10 years, 30 male) with acute myocardial infarction (AMI) who developed no-reflow phenomenon during primary percutaneous coronary intervention (PCI) between June 2001 and May 2003 comprised the study group, which was divided into 2 groups: group I [25 patients, 67±10 years, 13 male; adenosine (24 μg/ml) alone in addition to nitrate] and group II [25 patients, 66±9 years, 17 male; combined intracoronary administration of adenosine and nicorandil (2 mg/ml) in addition to nitrate]. In-hospital and 6-month major adverse cardiac events (MACE) after PCI were compared between the 2 groups. Risk factors of coronary disease, left ventricular ejection fraction and wall motion score were not significantly different between the 2 groups (p=NS). Time interval from the onset of chest pain to PCI, number of involved vessels, lesion type according to ACC/AHA classification and TIMI flow grade (TFG) were not significantly different in both groups (p=NS). Incidence of thrombosis or dissection after balloon angioplasty, diameter and length of stent, and use of Reopro® during PCI were not significantly different. TFG after PCI (2.0±0.9 vs 2.6±0.6, p=0.024), ΔTFG (1.5±1.1 vs 2.2±1.0, p=0.033) and difference in TIMI frame count (TFC) before and after PCI (ΔTFC) were greater in group II than group I (45.2±24.5 vs 63.6±23.2, p=0.014). Myocardial blush score 3 was obtained more frequently in group II than group I (44% vs 76%, p=0.014). In-hospital death did not occur in any of group II, but 4 patients of group I died (p=0.043). Two cases of MACE developed in each group and heart failure occurred in 3 (12%) of group I and 1 (4%) of group II patients during the 6-month follow-up (p=NS). Conclusions Intracoronary administration of adenosine combined with nicorandil may improve both the occurrence of no-reflow in patients during PCI for AMI and short-term clinical outcome, compared with adenosine alone. (Circ J 2004; 68: 928 - 932)

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Background Dilated cardiomyopathy (DCM) is generally considered to be accompanied by both left and right ventricular dysfunction, but most studies only analyze the left ventricular function. Methods and Results Biplane right ventriculography was performed in 13 control subjects and 13 patients with DCM and New York Heart Association functional class II. Three dimensions of the right ventricle (RV) (the long axis dimension (LA), the anterior - posterior dimension (AP), and the septum -free wall dimension (SF)) and 2 dimensions of the left ventricle (LV) (LA and AP) were examined to assess regional function. The group with DCM had a lower stroke volume index and RV ejection fraction. In the RV dimensional analysis, the group with DCM had a smaller SF and a larger AP at end-diastole, and larger AP and LA at end-systole. There was a significant linear negative correlation between SF of RV and AP of LV at end-diastole. Conclusion In clinically well-controlled cases of DCM, RV systolic function is depressed, and the RV is compressed by the LV, becoming less thick than in the controls. This transformation results from some parallel interaction between the RV and a markedly enlarged LV. (Circ J 2004; 68: 933 - 937)

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Background The adaptation of patients with acute myocardial infarction (AMI) to a phase I rehabilitation program has not been widely assessed. Methods and Results Forty-two male patients (62±8 years) with AMI were classified as exercise tolerant (group A, n=25) or excessive response (systolic blood pressure (SBP) increase >30 mmHg during exercise; group B, n=17). Hemodynamic parameters during exercise using a cycle-ergometer were monitored for the first 3 days. The power of low- and high-frequency components (LF: 0.05-0.2 Hz; HF: 0.2-1 Hz) was analyzed by heart rate variability. Anxiety status was assessed using the Spielberger's State-Trait Anxiety Inventory. Patients in group B were significantly older, had lower cardiac function and a longer hospitalization than group A (p<0.05, respectively). The excessive elevation of SBP on Day 1 decreased and became <30 mmHg on Day 3 in group B. The decreases in HF during exercise on Days 1 and 3 were significantly smaller in group B than in group A (p<0.05 and p<0.05, respectively). The LF/HF ratio on Day 1 was significantly higher in group B than in group A (p<0.05). In group B, the anxiety score before exercise was significantly higher than that at the time of discharge (p<0.05), whereas there was no change in group A. Conclusion Factors influencing a significant elevation of blood pressure during phase I rehabilitation are age, physical deconditioning, imbalance of autonomic nervous activity and anxiety. (Circ J 2004; 68: 938 - 945)

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Background The effect of physical training (PT) on QTc dispersion and ventricular tachycardia (VT) remains unclear in patients with nonischemic heart failure. Methods and Results Eight patients with nonischemic heart failure performed PT using a bicycle ergometer and their exercise tolerance increased (4.9±1.8 to 7.0±2.5 METs, p<0.05) and QTc dispersion decreased (71±22 to 48±24 ms, p<0.05). However, PT did not change the frequency of VT. Conclusion Physical training could improve QTc dispersion in patients with nonischemic heart failure, possibly by improving the autonomic nerve system. (Circ J 2004; 68: 946 - 949)

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Background Low-dose dobutamine stress echocardiography (LDDE) has become a useful and safe method for identifying hibernating or stunned myocardium and for predicting improvement in wall motion after coronary revascularization. Methods and Results In the present study, fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET), rest-redistribution thallium-201 (²⁰¹Tl) single-photon emission computed tomography (RR-Tl SPECT), ¹²³I-15-(p-iodophenyl)-3-(R,S)-methyl pentadecanoic acid (BMIPP) and LDDE were performed in 30 patients with acute myocardial infarction (AMI) at 10±3 days after the onset of AMI. Also, exercise ²⁰¹Tl reinjection SPECT (RI-Tl SPECT) was performed at 14±2 days. Follow-up echocardiography was performed 5±3 months later in all patients after interventional therapy for the assessment of functional recovery. Of the 390 segments analyzed by echocardiography, 110 (28%) had abnormal wall motion. There were no significant differences between RR-Tl SPECT and LDDE in sensitivity, specificity, positive predictive value and negative predictive value using the χ²-test; however, in akinetic segments, there was a significant difference in sensitivity. Among FDG-PET, RI-Tl SPECT, BMIPP and LDDE, there were significant differences in 3 variables. In akinetic segments, LDDE is superior to RR-Tl SPECT in sensitivity and to FDG-PET in specificity. In hypokinetic segments, LDDE is superior to RI-Tl SPECT and BMIPP in sensitivity, and to FDG-PET and BMIPP in specificity. Conclusions LDDE could detect functional recovery of viable myocardium in the early period of AMI and can be performed easily and safely. (Circ J 2004; 68: 950 - 957)

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A patient who had myelodysplastic syndrome (MDS) and dilated cardiomyopathy (DCM) had a transient improvement of cardiac function after peripheral blood stem cell transplantation (PBSCT). When he was admitted to hospital for PBSCT, a chest X ray showed cardiomegaly, and Tc-99m quantitative gated single photon emission computed tomography (QGS) showed increases in left ventricular (LV) volumes and a decrease in LV ejection fraction (LVEF). A coronary angiogram showed no evidence of coronary artery disease. Left ventriculography showed similar findings as QGS, and the findings from a myocardial biopsy were compatible with DCM. Three months after a successful allo-PBSCT with his brother as the donor, the cardiomegaly had been attenuated, the LV volumes decreased and LVEF increased on the QGS images. However, 10 months later, his cardiac function had deteriorated. The changes in cardiac function did not correlate with the hematological changes, such as the hemoglobin level. (Circ J 2004; 68: 958 - 960)

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A transthoracic echocardiogram revealed 3 tumors in the left atrium of a 64-year-old woman, who died suddenly 8 months after resection of the tumors. Primary cardiac tumors are unusual and a case of postoperative left ventricular metastases of the atrial tumors resulting in left ventricular outflow tract obstruction is very rare occurrence. (Circ J 2004; 68: 961 - 963)

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Noncompaction of the ventricular myocardium (NVM) is a rare disorder of endomyocardial morphogenesis characterized by numerous, prominent trabeculations and deep intertrabecular recesses. It is commonly associated with congenital heart disease, but the isolated form (INVM) is not associated with other structural heart diseases. Clinical reports of INVM have been limited to a few case reports and small series of pediatric patients. INVM is considered to be a form of congenital abnormal endomyocardial morphogenesis caused by abnormal cessation of the embryonic development of the ventricular myocardium; most reported cases have been pediatric patients, and autopsy cases of elderly patients have been quite rare. In the present case, an elderly female had INVM associated with severely disturbed left ventricular (LV) function and an enlarged left ventricle similar to dilated cardiomyopathy. The echocardiogram showed prominent trabeculations and deep intertrabecular recesses of the LV walls, especially in the posterior and apical areas. LV contrast echocardiography revealed markedly protruberant trabeculations, which were also observed with computed tomography. Five years later, the patient died of refractory heart failure and ventricular fibrillation. The autopsy revealed numerous excessively prominent trabeculations in the LV myocardium, with deep intertrabecular recesses containing thrombi. (Circ J 2004; 68: 964 - 967)

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An 83-year-old woman with hypertension was admitted to hospital with episodes of dyspnea on effort after having breakfast. Physical examination revealed a systolic murmur at the left sternal border in the third to fourth intercostal space. Cross-sectional echocardiography showed a sigmoid-shaped interventricular septum markedly protruding into the left ventricle, concentric left ventricular hypertrophy, systolic anterior motion of the mitral valve, and a resultant left ventricular outflow tract obstruction with a pressure gradient of 121.8 mmHg. She began daily treatment with 60 mg metoprolol. However, the chest symptoms were not relieved and the left ventricular outflow tract obstruction was still visible on echocardiography. She was then given 200 mg daily of cibenzoline, in addition to 40 mg metoprolol, and the left ventricular pressure gradient significantly decreased and she was free of symptoms without any complications. This case shows that cibenzoline may be useful in the treatment of left ventricular outflow tract obstruction caused by sigmoid septum. (Circ J 2004; 68: 968 - 971)

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Background There have not been previous reports of patients undergoing percutaneous coronary intervention (PCI) using a gadolinium chelate. Methods and Results A 74-year-old woman, who had a history of anaphylactic shock 4 times in response to iodinated contrast media despite preprocedural intravenous administration of hydrocortisone, was hospitalized because of unstable angina refractory to intensive medical treatment. Fully considering the risks of iodinated agents, digital subtraction coronary angiography and PCI were performed using gadopentetate dimeglumine without any side effects or complications. Conclusions Gadolinium chelates can be an alternative contrast media during PCI in particular patients with contraindications to iodinated media. (Circ J 2004; 68: 972 - 973)

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Wrong:It has been reported that the ≥60 ms) and PQ interval (≥210 ms) at baseline, and excessive QRS interval prolongation after Na+-channel blockade, was more likely to be found in patients with Brugada syndrome who were carriers of an SCN5A mutation.
Right:It was reported that the presence of conduction defects, as evidenced by a prolonged HV interval (≥60 ms) and PQ interval (≥210 ms) at baseline, and excessive QRS interval prolongation after Na+-channel blockade, was more likely to be found in patients with Brugada syndrome who were carriers of an SCN5A mutation.

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