In recent years there has been renewed interest in beating heart surgery using the ultra-active and selective β₁-blocker, esmolol. However, there has not been a report of its use in direct version intracardiac surgery with beating heart. Twenty-four patients undergoing elective direct version intracardiac surgery (mitral valve replacement) were divided randomly into 2 groups: control group (normothermia cardiopulmonary bypass (CPB) direct version intracardiac beating heart surgery) and esmolol group (normothermia CPB direct version intracardiac beating heart surgery and intravenous esmolol drip during CPB to maintain heart rate at 30-50 beats/min). Steady hemodynamic parameters were maintained in both groups; however, the doses of dopamine used in control group were larger than those for the esmolol group (p<0.01). The myocardial ultrastructure was well maintained in both group, but the scores for myocardial mitochondria, glycogen grading and counting and the amount of adenosine triphosphate were higher in the esmolol group (p<0.05). There was no significant change in the malondialdehyde level in either group (p>0.05). Using esmolol in direct version intracardiac beating heart surgery protects the myocardium and facilitates the operation. (Circ J 2002; 66: 715 - 717)

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The effect on myocardial reperfusion injury of reducing oxygen tension during reperfusion on cardiopulmonary bypass (CPB) in coronary artery bypass grafting (CABG) was examined at the same time as the influence of diltiazem during CPB was evaluated. A prospective, randomized trial evaluated the hemodynamic and myocardial metabolic recovery in 3 groups of patients undergoing elective CABG; subjects were randomly allocated on the basis of oxygen tension during reperfusion after aortic unclamping: group 1 (n=10) hyperoxic reperfusion (oxygen tension [PO₂] = 450-550 mmHg); group 2 (n=10): hyperoxic reperfusion and subsequent continuous infusion of diltiazem (0.5 μg/kg); group 3 (n=10): lowering reperfusate PO₂ (PO₂ = 200-250 mmHg). Hemodynamic and myocardial metabolic measurements were taken at 6 preset times: before starting the surgical procedure and at 30 min and 3, 9, 21, and 45 h after discontinuation of CPB. The cardiac index in the lowering reperfusate PO₂ group was higher than that of the hyperoxic reperfusion groups at 30 min and 3 h after CPB, and malondialdehyde and troponin-T were significantly lower at 30 min and 3 h, respectively. In comparison with the hyperoxic + diltiazem group, the hemodynamic and myocardial recovery in the lowering reperfusate PO₂ group was improved for about 3 h after CPB. Reduced oxygen tension during reperfusion after aortic unclamping on CPB is more effective against myocardial injury than a calcium antagonist in the short term. It is a convenient and safe management technique that can reduce morbidity and mortality, especially in the severely compromised heart. (Circ J 2002; 66: 718 - 722)

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Beta-1-adrenergic receptor (β₁-AR) blockers reduce both the incidence of sudden death and the ventricular volume in heart failure. In vitro, the Gly389 variant of β₁-AR mediates less adenylyl cyclase activities than the Arg389 variant, so Arg389Gly polymorphism was investigated with regard to the genesis, progression, or arrhythmogenesis of dilated cardiomyopathy (DCM). Allele and genotype frequencies of the Arg389Gly polymorphism were determined in 163 DCM patients and 157 age- and sex-matched controls. There were no differences in genotype and allele frequencies between patients and controls. Echocardiograms, left ventriculograms and 24 h-Holter electrocardiograms were evaluated in the DCM patients and none of the clinical indices, other than ventricular tachycardia (VT), differed among the 3 genotypes. The Gly389 allele was more frequent in the VT(-) group than in the VT(+) group (0.46 vs 0.24, p=0.001). In univariate analysis, the odds ratio for VT in patients carrying 1 or 2 copies of the Gly389 allele was 0.29 ([95% confidence interval, 0.13-0.64], p=0.002), when compared with the Arg389 homozygotes. The Gly389 variant supressed the occurrence of VT in DCM, suggesting that this allele confers a decreased risk of sudden death. (Circ J 2002; 66: 723 - 728)

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This study measured integrated backscatter (IB) values in the subendocardium and subepicardium of patients with hypertrophy using the newly developed Backscattered Energy Temporal Analysis (BETA) system, and evaluated the differences of acoustic properties according to etiology. Twenty-one patients with hypertrophic cardiomyopathy (HCM), 16 with pressure-overloaded hypertrophy (POH), and 21 controls were studied. M-mode formatted IB images were obtained using BETA and the region of interest (ROI), automatically divided into epicardial and endocardial halves of the myocardium, was placed in the ventricular septum and posterior wall. Values for the cyclic variation of IB (CVIB) in the entire ROI and in each half of the ROI were obtained. CVIB significantly decreased in the ventricular septum in HCM and POH compared with normal subjects, but there were no significant differences between HCM and POH. In the posterior wall, the CVIB was less in the subendocardium than in the epicardium in POH, and was also less than in normal subjects (7.0±1.7 dB vs 8.6±1.9 dB and 8.8±2.1 dB, p<0.05, respectively). Separate ultrasonic tissue characterization of the subendocardium and subepicardium provides further etiological information of various heart diseases. (Circ J 2002; 66: 729 - 734)

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Although previous studies have demonstrated that even quantitative coronary angiography (QCA) can not provide accurate disease morphology, there has not been a systematic comparison of disease morphology determined by QCA and intravascular ultrasound (IVUS), particularly in Japanese patients. Therefore, the present study prospectively examined patients in a multicenter cooperative study. A total of 491 coronary sites from 562 patients (446 men, 116 women; mean age, 64±11 years) who underwent coronary interventions were enrolled. The target lesions (>50% diameter stenosis) were evaluated pre-operatively by both QCA and IVUS operating at 30-40 MHz and the percent area stenosis, eccentricity index (EI) and lesion length were determined. The minimal (min) and maximal (max) distances from the center of the stenotic lesion to the outline of the vessel wall were measured, and the EI was calculated by the formula: {(max - min) / max}. By QCA, lesion length was determined by measuring the distance between the proximal and distal shoulders of the lesion. When the lesions were observed by IVUS with a motorized pull-back system, the length was calculated by multiplying the time for observation of the disease and 0.5 or 1 mm/s. Although the severity of the stenosis determined by QCA (86±10%, mean ± SD) did not differ from that by IVUS (83±13%), there was no correlation between them (r=0.32, y = 0.25x + 65) and the correlation did not improve when lesions with remodeling, enlargement (n=176) or shrinkage (n=79) were omitted from the calculation. The EIs by QCA and IVUS were 0.51±0.26 and 0.52±0.22, respectively (NS), and there was no correlation between them (r=0.30, y = 0.36x + 33). However, when the lesions with remodeling were excluded, the correlation greatly improved (r=0.80, y = 0.84x + 10.6, p<0.05). Lesion length determined by QCA (12.4±6.1 mm) was significantly shorter than that by IVUS (16.3±8.9 mm, p<0.01). These results demonstrate that coronary angiography significantly misinterprets disease morphology in terms of severity, eccentricity and length, in part because of vessel remodeling that can be accurately determined only by IVUS. (Circ J 2002; 66: 735 - 740)

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The main aim of this study was to elucidate whether the beneficial effect of antecedent angina is a cellular protective effect or the result of an increase of collateral flow. Of 42 patients with angina who underwent percutaneous transluminal coronary angioplasty (PTCA) for proximal left anterior descending artery (LAD) stenosis, 22 had experienced antecedent anginal pain (AP) within 7 days prior to PTCA. ^99mTc-sestamibi was injected during balloon inflation, and quantitative analysis of ischemic severity during coronary occlusion was calculated (SS). An electrocardiogram was recorded during ballooning to calculate the sum of ST elevation (ΣST). ΣST was significantly reduced in patients with AP compared with patients without AP (1.88±0.89 mV vs 1.18±0.74 mV, p=0.0088); however, no difference was observed in defect severity. A close correlation was observed between SS and ΣST in both groups. The multivariate regression model demonstrated that both a large SS (p<0.0001) and the absence of preceding AP (p=0.001) were significantly related to the elevation of ΣST. Recent angina can render the myocardium more resistant to subsequent ischemia during angioplasty and is true preconditioning rather than simply an increase of flow. (Circ J 2002; 66: 741 - 745)

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Recently, the routine use of dual-chamber implantable cardioverter defibrillators (DC-ICD) has been advocated over the single-chamber version (SC-ICD), but there are few reports of the frequency of complications between the 2 types of ICDs. Between July 1997 and April 1999, 178 consecutive patients underwent implantation of either a transvenous SC-ICDs (n=104) or a DC-ICDs (n=74). Twelve (16%) of the 74 patients with a DC-ICD had a total of 16 major complications compared with 6 (6%) of the 104 patients with a SC-ICD (p=0.01). The 16 DC-ICD complications included atrial lead dislodgment (4), ventricular lead malfunction (4), and pocket infection/hematoma (3), and the 6 SC-ICD complications included ventricular lead dislodgment (2) and pocket hematoma (3). Patients with a DC-ICD had less left ventricular function (29% vs 35%, p=0.035) and a higher prevalence of non-ischemic cardiomyopathies (48% vs 28%, p=0.0076). In conclusion, the DC-ICD may have a higher frequency of device- and lead-related major complications. (Circ J 2002; 66: 746 - 750)

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To assess the validity of accelerometry in measuring daily physical activity, the energy consumption calculated by accelerometry, with respiratory gas analysis as a reference, was evaluated in 45 non-athletes during various exercise tests. Subjects were required to (1) walk on a treadmill ergometer at various speeds, (2) walk on a treadmill ergometer at a fixed speed and with a stride of 20% more or 20% less than that when walking freely, (3) walk on a treadmill ergometer at a fixed speed wearing either sneakers or leather-soled shoes, and (4) cycle on a bicycle ergometer. There were strong linear relationships between the measurements during the progressively graded treadmill test, with an overall Pearson correlation coefficient of 0.97. The mean estimated difference ranged from -0.77 to 0.27 kcal/min and the coefficients of variation from 13.2% to 22.2%. However, the difference between the methods was not negligible for individual subjects. Accelerometry overestimated energy expenditure during short-step walking, and underestimated it during long-step walking. No significant difference in energy expenditure was found according to the type of shoes worn. Cycling activity was not recorded by accelerometry. Accelerometry is a reasonably accurate and feasible method for evaluating the physical activities of non-athletes, and could be a common tool for epidemiological research and health promotion despite its limitations. (Circ J 2002; 66: 751 - 754)

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Abdominal aortic aneurysm (AAA) is commonly associated with coronary artery disease (CAD). Eleven patients underwent the combined operation of coronary artery bypass grafting (CABG) on the beating heart and AAA repair: 10 underwent off pump CABG and 1 patient required centrifugal pump and pulmonary assist with closed circuit because of unstable hemodynamics. All cases were discharged without severe complications and with patent coronary bypass grafts. (Circ J 2002; 66: 755 - 757)

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Amiodarone effectively blocks both the sodium and calcium channels and β-adrenoceptors, in addition to blocking several potassium currents including I_Kr, I_Ks, I_to, I_K1, I_KACh and I_KNa. The incidence of clinical torsade de pointes (TdP) associated with amiodarone has been reported to be low and the present study compared the proarrhythmic potential of amiodarone with that of a selective I_Kr channel blocker, sematilide, using a canine chronic atrioventrucular block model. Amiodarone or sematilide (3 and 30 mg/kg; n=4 for each group) was administered orally without anesthesia under continuous ECG monitoring. Both drugs prolonged the QT interval, although the onset was faster for sematilide. The high dose of sematilide induced TdP in 3 of 4 animals, which caused their death, but neither the low dose of sematilide nor the 2 dosages of amiodarone induced lethal ventricular arrhythmias. These results suggest that I_Kr channel inhibition by amiodarone with its additional ion channel blocking action may contribute to the prevention of TdP. (Circ J 2002; 66: 758 - 762)

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The present study used isolated rat hearts to investigate whether (1) Sheng-Mei-San (SMS), a traditional Chinese formulation comprising Radix Ginseng, Radix Ophiopogonis and Fructus Schisandrae, is protective against post-ischemic myocardial dysfunction, and (2) whether the cardioprotective effect of SMS is related to scavenging of hydroxyl radicals and opening the mitochondrial K_ATP channels. The excised hearts of male Sprague-Dawley rats were perfused on a Langendorff apparatus with Krebs-Henseleit solution with a gas mixture of 95% O₂ and 5% CO₂. Left ventricular end-diastolic pressure (LVEDP, mmHg), left ventricular developed pressure (LVDP, mmHg), ±dP/dt (mmHg/s) and coronary flow (ml/min) were continuously monitored. All hearts were perfused for a total of 120 min consisting of a 30-min pre-ischemic period followed by a 30-min global ischemia and 60-min reperfusion. Lactate, lactate dehydrogenase (LDH) and 2,5-dihydroxybenzoic acid (2,5-DHBA) concentrations in the effluent were measured during reperfusion. Three days' treatment with SMS (1.67 ml/kg per day) inhibited the rise in LVEDP and improved the post-ischemic LVDP and ±dP/dt significantly better than in the untreated control hearts during reperfusion. SMS increased the coronary flow at baseline, and during reperfusion. Pretreatment with 5-hydroxydecanoic acid (5-HD), a mitochondrial K_ATP channel blocker, abolished the inhibition of the rise in LVEDP, the increase in coronary flow and the improvement in LVDP and ±dP/dt induced by SMS. SMS significantly attenuated the concentrations of lactate, LDH and 2,5-DHBA during reperfusion, but the pretreatment with 5-HD restored them; 5-HD alone did not affect the concentrations. SMS improved the post-ischemic myocardial dysfunction through opening the mitochondrial K_ATP channels. (Circ J 2002; 66: 763 - 768)

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A 65-year-old man was admitted to the National Defense Medical College Hospital for acute anterolateral myocardial infarction and cardiogenic shock. Emergency coronary angiography demonstrated occlusion of the proximal left anterior descending artery. Primary percutaneous transluminal coronary angioplasty (PTCA) was successfully performed with the support of intra-aortic balloon pumping (IABP) and medical treatment to stabilize the patient's blood pressure. On the second hospital day, the patient suffered cardiac tamponade. Pericardiocentesis showed bloody fluid and revealed that an oozing-type of left ventricular rupture had occurred after the myocardial infarction. Cardiogenic shock persisted after successful removal of the pericardial effusion. Although the heparinization required during percutaneous cardiopulmonary support (PCPS) can increase pericardial effusion, PCPS was initiated to correct the systemic hypoperfusion; a surgical team was on standby in case massive pericardial effusion resulted, but fortunately that did not occur, and cardiac function recovered. The patient was weaned successfully from PCPS and IABP and has remained in a satisfactory condition for over 1 year. PCPS contributed to the patient's recovery from cardiac shock and may have decreased the effusion from the oozing-type rupture by reducing ventricular wall tension. (Circ J 2002; 66: 769 - 772)

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A 67-year-old female non-smoker, who had been diagnosed with familial hypercholesterolemia associated with severe atherosclerosis of the coronary, carotid and vertebral arteries, developed interstitial pneumonia 4 months after initiating ticlopidine to inhibit platelet aggregation. The lymphocyte stimulation test by ticlopidine was positive and bronchoalveolar lavage fluid showed an increase in lymphocytes and a decrease in the CD4⁺/8 ⁺ ratio, suggesting potentially undesirable side effects of ticlopidine. Two months after ticlopidine therapy was discontinued and prednisolone therapy started, the interstitial pneumonia had almost completely resolved. Two patients, one with ticlopidine-associated bronchiolitis obliterans organizing pneumonia and the other with pneumonia with multiple nodules, have been reported to date and the present patient is the third reported case of ticlopidine-induced pneumonia. The incidence of this side effect may not be so high because approximately 20 years have passed since ticlopidine was first marketed in Japan, but because the drug is now widely prescribed, this serious clinical side effect should be considered. (Circ J 2002; 66: 773 - 776)

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A 64-year-old woman with a history of cerebral infarction from chronic occlusion of the middle cerebral artery presented with acute myocardial infarction. Double, off-pump coronary artery bypass grafting could not prevent stroke caused by atheroembolism from the ascending aorta. The risk of stroke from atheroembolism should be taken into consideration when planning coronary artery bypass grafting. (Circ J 2002; 66: 777 - 778)

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In August 1998, the patient, a 75-year-old woman, was diagnosed with pericardial effusion (PE) during an investigation of cardiomegaly. The PE disappeared after the administration of diuretics, but in February 1999, shortness of breath and general fatigue developed, and PE was again present. Diagnostic pericardiocentesis revealed bloody fluid. Chest computed tomography revealed a markedly expanded and tortuous right coronary artery (RCA). Coronary angiography (CAG) confirmed a RCA - coronary sinus fistula, and there was a significant step-up of O₂ saturation at the right atrium. Cardiac tamponade developed soon after CAG, so the patient underwent surgical closure of the CAVF. Although a bleeding point was not identified, the PE was disappeared after operation. Histopathologically, parts of the wall of the fistula were quite thin and erythrocytes and lymphocytes had infiltrated the pericardial space. The clinical course and the findings indicate that the CAVF caused chronic PE. (Circ J 2002; 66: 779 - 782)

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