Kazuteru Fujimoto

Nitric Oxide Activity Is Deficient in Spasm Arteries of Patients With Coronary Spastic Angina

BACKGROUND Coronary spasm can be induced by acetylcholine, serotonin, ergonovine, or histamine, all of which cause vasodilation when the endothelium is intact by releasing nitric oxide (NO). Coronary spasm is promptly relieved by nitroglycerin, which vasodilates through its conversion to NO. It is thus possible that NO release may be deficient in the spasm arteries in patients with coronary spastic angina (CSA). The aim of this study was to determine whether NO release is deficient in coronary arteries of patients with CSA. METHODS AND RESULTS NG-monomethyl-L-arginine (L-NMMA), an inhibitor of NO synthase, was infused into coronary arteries in 21 patients with coronary spastic angina (CSA) and in 28 control patients. Coronary spasm was induced by intracoronary injection of acetylcholine and was documented angiographically in all patients with CSA. L-NMMA dose-dependently decreased basal luminal diameter of coronary arteries in control patients, whereas it had no effect on basal diameter of the spasm arteries in patients with CSA. L-NMMA abolished the dilator response to acetylcholine and enhanced the constrictor response to acetylcholine in control arteries, whereas it had no effect on the constrictor response to acetylcholine in spasm arteries. Intracoronary infusion of L-arginine did not affect the diameter of spasm or control arteries. The dilator response to nitroglycerin was increased markedly in spasm arteries compared with control arteries, whereas response to diltiazem did not differ between them. CONCLUSIONS There is a deficiency in endothelial NO activity in spasm arteries, which leads to the supersensitivity of the artery to the vasodilator effect of nitroglycerin and to the vasoconstrictor effect of acetylcholine in patients with CSA. This deficient endothelial NO activity plays an important role in the pathogenesis of coronary spasm.

Lysophosphatidylcholine in oxidized low-density lipoprotein increases endothelial susceptibility to polymorphonuclear leukocyte-induced endothelial dysfunction in porcine coronary arteries. Role of protein kinase C.

We have shown that transferred lysophosphatidylcholine (lysoPC) from oxidized low-density lipoprotein (Ox-LDL) to endothelial surface membrane activates protein kinase C (PKC) in endothelial cells, suggesting that Ox-LDL could alter endothelial functions through PKC activation. The purposes of the present study were to examine whether the endothelial susceptibility to polymorphonuclear leukocytes (PMNs) may be altered in Ox-LDL-treated coronary arteries, which have properties closely resembling those observed in atherosclerotic arteries, and to determine the mechanism(s) by which Ox-LDL may affect the endothelial susceptibility to PMNs. Isolated porcine coronary arteries were cannulated and perfused with oxygenated culture medium with or without LDLs or lipids at a constant flow (37 degrees C, pH 7.4). The treatment of porcine coronary arteries with Ox-LDL increased endothelial adhesiveness to PMNs and augmented PMN-induced impairment of endothelium-dependent arterial relaxation (EDR). Furthermore, Ox-LDL stimulated the expression of intercellular adhesion molecule-1 (ICAM-1) in the porcine coronary arterial endothelium. These effects of Ox-LDL were not mediated by the scavenger-receptor-mediated process but were attributed to lysoPC in Ox-LDL. Blocking of the PMN adherence to endothelium by using anti-CD18 monoclonal antibody abolished the PMN-induced impairment of EDR. Coincubation with staurosporine or calphostin C, inhibitors of PKC, during treatment of the arteries with Ox-LDL or lysoPC attenuated the augmentative effects of Ox-LDL and lysoPC on endothelial ICAM-1 expression, endothelial adhesiveness to PMNs, and PMN-induced EDR impairment. Treatment of the arteries with phorbol 12-myristate 13-acetate, a potent stimulator of PKC, induced ICAM-1 expression and enhanced the endothelial adhesiveness to PMNs and PMN-induced EDR impairment, mimicking the effects of Ox-LDL. These results suggest that lysoPC in Ox-LDL induces endothelial ICAM-1 expression, which facilitates PMN adherence to endothelium and the subsequent augmentation of PMN-induced EDR impairment. PKC activation in endothelial cells by lysoPC in Ox-LDL may at least in part be involved in these effects of Ox-LDL. LysoPC in Ox-LDL increases endothelial susceptibility to PMN-induced endothelial dysfunction.

Hyperventilation as a Specific Test for Diagnosis of Coronary Artery Spasm

The hyperventilation test has been used as a clinical tool to induce coronary spasm. However, its diagnostic and prognostic values have not been fully elucidated. This study was designed to establish the sensitivity and specificity of the hyperventilation test and to clarify the characteristics of hyperventilation test-positive patients. We examined 206 patients in whom coronary spasm was documented by angiography (spasm group), and 183 patients without angina at rest in whom acetylcholine failed to induce spasm (nonspasm group). All patients performed vigorous hyperventilation for 6 minutes in the early morning. Of the spasm group patients, 127 showed positive responses to the test, including ST elevation (n = 111), ST depression (n = 15) and negative U wave (n = 1). None in the nonspasm group showed any ischemic electrocardiographic change. Thus, the sensitivity and specificity of this test for diagnosis of coronary spasm were 62% and 100%, respectively. In the spasm group, there were no significant differences between hyperventilation test-positive and test-negative patients in age, sex, the prevalence of hypertension, diabetes mellitus, obesity, smoking, and the number of diseased vessels. When clinical characteristics were compared, the proportions of the patients with high disease activity (> or =5 attacks a week), with severe arrhythmias (second- or third-degree atrioventricular block and/or ventricular tachycardia) during attacks, and with multivessel spasm were significantly higher in the hyperventilation test-positive patients than in the negative patients (69% vs 20%, p <0.0001; 31% vs 11%, p <0.005; and 58% vs 34%, p <0.01, respectively). These findings imply that hyperventilation is a highly specific test for the diagnosis of coronary artery spasm, and that hyperventilation test-positive patients are likely to have life-threatening arrhythmias during attacks and multivessel spasm.

Expression of Angiotensin-Converting Enzyme in Remaining Viable Myocytes of Human Ventricles After Myocardial Infarction

BACKGROUND Local ACE in the heart may be important in the pathophysiological state after myocardial infarction (MI). It is unknown, however, whether ACE is expressed in myocytes of the human heart. METHODS AND RESULTS Using a newly generated polyclonal antibody to a synthetic peptide corresponding to part of the human endothelial ACE sequence, we examined the localization of ACE in left ventricles of patients (n = 10) with MI obtained at left ventricular aneurysmectomy or autopsy and in the hearts of control subjects at autopsy (n = 10). The avidinbiotinylated peroxidase complex method was used for the immunohistochemical staining for ACE. In the left ventricles, positively stained myocytes for ACE were found in 8 of the 10 patients with MI. ACE immunoreactivity was seen in the remaining viable myocytes located near the infarct scar of the aneurysmal left ventricle and in nonmyocytes such as fibroblasts, macrophages, vascular smooth muscle cells, and endothelial cells within the scarred tissue. On the other hand, no immunoreactivity for ACE was detected in the ventricular myocytes of all control hearts obtained at autopsy. CONCLUSIONS We observe immunohistochemical staining for ACE in the left ventricular myocytes of the region adjacent to the infarct scar and in nonmyocytes. These results indicate that ACE is markedly increased on the edge of the infarct scar and suggest that local ACE may be important in the ventricular remodeling after MI.

Increased angiotensin converting enzyme activity in left ventricular aneurysm of patients after myocardial infarction

OBJECTIVE Angiotensin converting enzyme (ACE) inhibitors have been shown to improve left ventricular dysfunction and survival in patients with chronic myocardial infarction. The aim of this study was to examine the ACE activity in infarcted tissues in such patients in comparison with non-diseased tissues from control subjects obtained at necropsy. METHODS ACE activity was measured in the left ventricles and right atrial auricles of patients (n = 9) with chronic myocardial infarction obtained at left ventricular aneurysmectomy, and in the hearts of control subjects at necropsy (n = 10). RESULTS In non-diseased hearts, the ACE activity was highest in right atria and auricles [2.4(SEM 0.2), 2.2(0.3) nmol.mg-1 protein.min-1, NS, respectively], followed by left atria [1.7(0.2)], left auricles [1.5(0.1)], right ventricles [1.0(0.2)], and left ventricles [0.5(0.1)]. The ACE activity was significantly increased in aneurysmal tissues of patients with chronic myocardial infarction relative to left ventricles of control subjects [4.2(0.4) v 0.5(0.1) nmol.mg-1 protein.min-1, P < 0.01]. There was, however, no difference in the ACE activity of right atrial auricles between patients with chronic myocardial infarction and control subjects [2.8(0.5) v 2.2(0.3), NS]. In patients with chronic myocardial infarction, the ACE activity was higher in left ventricles than in right auricles (P < 0.01). The ACE activities in the infarcted and control ventricles were negatively correlated with the membrane protein content (r = -0.77, P < 0.01). CONCLUSIONS In non-diseased human hearts, the ACE activity is higher in atria than in ventricles and higher in the right than in the left ventricle. Furthermore, the ACE activity in aneurysmal left ventricular tissue after myocardial infarction is higher than in non-diseased left ventricular myocardium. These results suggest that the local ACE in the human heart may play an important role in the pathophysiological state after myocardial infarction.

Clinical Presentation, Management and Outcome of Japanese Patients With Acute Myocardial Infarction in the Troponin Era – Japanese Registry of Acute Myocardial Infarction Diagnosed by Universal Definition (J-MINUET) –

BACKGROUND New criteria for diagnosis of acute myocardial infarction (AMI) were proposed in 2000 as a universal definition, in which cardiac troponin (cTn) was the preferred biomarker. A large number of patients formerly classified by creatine kinase (CK) as unstable angina are now ruled-in by cTn as non-ST-elevation myocardial infarction (NSTEMI). METHODS AND RESULTS The Japanese registry of acute Myocardial INfarction diagnosed by Universal dEfiniTion (J-MINUET) is a prospective and multicenter registry conducted in 28 institutions. We enrolled 3,283 consecutive patients with AMI diagnosed by cTn-based criteria who were admitted to participating institutions within 48 h of symptom onset. There were 2,262 patients (68.9%) with STEMI and 1,021 (31.1%) with NSTEMI. CK was not elevated more than twice the upper limit of normal in 458 patients (44.9%) with NSTEMI (NSTEMI-CK). Although there was no significant difference in the in-hospital mortality of STEMI and NSTEMI with CK elevation (NSTEMI+CK) patients (7.1% vs. 7.8%, P=0.57), it was significantly lower in patients with NSTEMI-CK than in those with STEMI or NSTEMI+CK (1.7%, P<0.001 for each). CONCLUSIONS J-MINUET revealed the clinical presentation, management and outcomes of Japanese patients with AMI in the current cTn era. We should be aware of the difference between AMI diagnosed by CK-based criteria and AMI diagnosed by cTn-based criteria when using universal definitions for the diagnosis of AMI.

Heart rate on admission is an independent risk factor for poor cardiac function and in-hospital death after acute myocardial infarction

BACKGROUND Increased resting heart rate (HR) due to sympathetic hyperactivity is associated with coronary risk factors and increased cardiovascular events. Acute myocardial infarction (AMI) is accompanied by autonomic imbalance, which is characterized by sympathetic activation and parasympathetic inactivation. Although an increased HR in patients with acute coronary syndrome has been reported to be associated with 30-day and 6-month mortality before the coronary intervention era, it is unclear if an increased HR on admission is associated with the prognosis of AMI in the coronary intervention era. METHODS We enrolled 200 consecutive patients with AMI within 24 h of symptom onset. All patients underwent coronary angiography. They were divided into quartiles based on resting HR on admission. RESULTS There was no difference in coronary risk factors and previous medical treatment among the four groups. Anterior AMI was significantly lower in the lowest quartile compared with other quartiles. There was no difference in peak creatine kinase value among the four groups, however left ventricular ejection fraction (LVEF) before discharge evaluated by echocardiography in the highest quartile group was significantly reduced compared to other quartiles. An increased HR was significantly associated with in-hospital death. Patients in the highest quartile of HR were about nine times more likely to have a poor prognosis after AMI compared to those in the lowest quartile. Multiple logistic analysis revealed that HR ≥93 was an independent risk factor for in-hospital death. HR was significantly associated with Killip class and LVEF on admission. CONCLUSIONS These findings indicate that increased HR on admission predicts for poor cardiac function and in-hospital death after AMI.

Therapeutic Neovascularization by the Implantation of Autologous Mononuclear Cells in Patients with Connective Tissue Diseases

Vasculopathy in patients with connective tissue diseases (CTDs), including systemic sclerosis (SSc) and systemic lupus erythematosus (SLE), is a serious complication that mainly affects small arteries and capillaries, reduces the blood flow and causes progressive tissue ischemia. Recently, CTD patients have been reported to have abnormalities in circulating endothelial progenitor cells (EPCs); these abnormalities are believed to contribute to the pathophysiology of vasculopathy and to the premature and accelerated development of atherosclerosis in CTD patients. Furthermore, we are currently conducting a clinical pilot study to determine the efficacy of implanting autologous mononuclear cells obtained from the bone marrow and peripheral blood into the ischemic digits or limbs of CTD patients. In this review, we discuss the role of EPCs in the process of neovascularization and in the pathophysiology of CTDs, and we describe a clinical pilot study on the use of autologous cell therapy for treating ischemic digits in patients with CTDs.

Differential Effects of Strong and Regular Statins on the Clinical Outcome of Patients With Chronic Kidney Disease Following Coronary Stent Implantation – The Kumamoto Intervention Conference Study (KICS) Registry –

BACKGROUND The aim of this study was to examine the effects of different statins on the clinical outcomes of Japanese patients with coronary stent implants. METHODS AND RESULTS This study included 5,801 consecutive patients (males, 4,160; age, 69.7±11.1 years, mean±SD) who underwent stent implantation between April 2008 and March 2011. They were treated with a strong statin (n=3,042, 52%, atorvastatin, pitavastatin, or rosuvastatin), a regular statin (n=1,082, 19%, pravastatin, simvastatin, or fluvastatin) or no statin (n=1,677, 29%). The patients with chronic kidney disease (CKD) were divided into mild-to-moderate CKD (30≤eGFR<60, n=1,956) and severe CKD (eGFR <30, n=559). Primary endpoints included cardiovascular death and nonfatal myocardial infarction, including stent thrombosis and ischemic stroke. The clinical outcome for the primary endpoint in mild-to-moderate CKD patients treated with a strong statin (hazard ratio 0.50, 95% confidence interval 0.31-0.81; P=0.005) was significantly lower than in those on no statins, but that in the patients treated with a regular statin was not (P=0.160). The clinical outcome for the primary endpoint in severe CKD patients treated with a strong or regular statin was no different than not being on statin therapy (P=0.446, P=0.194, respectively). CONCLUSIONS In patients with mild-to-moderate CKD, only strong statins were associated with lower risk compared with no statin, but regular statins were not. It is possible that taking a strong statin from the early stage of CKD is useful for suppression of cardiovascular events.

Increased expression of atrial myosin light chain 1 in the overloaded human left ventricle: possible expression of fetal type myocytes

We examined the isoforms of myosin light chain 1 in the human left ventricles using pyrophosphate and sodium dodecyl sulfate polyacrylamide gel electrophoresis, peptide mapping, and immunoblotting with monoclonal antibodies against human atrial light chain 1. The relationship between hemodynamic parameters and light chain 1 isoform composition was compared among groups of patients with hypertrophic cardiomyopathy (n = 8), dilated cardiomyopathy (n = 9) and aortic stenosis (n = 5), and controls (n = 6). (1) The light chain 1, which differed from ventricular light chain 1 found in the normal adult ventricle, was highly expressed in the overload left ventricle, and was identical to atrial and fetal ventricular light chain 1 with respect to the physiochemical and immunological properties. (2) The expression of atrial/fetal light chain 1 was augmented in the subendocardial area in comparison with the mid- or subepicardial areas in the hypertrophied left ventricles. (3) The values (%) of the relative expression of atrial/fetal light chain 1 to total light chains 1 determined by densitometric analysis were significantly higher in patients with dilated cardiomyopathy (40.2 +/- 5.8) and those with aortic stenosis (43.1 +/- 6.2) than in the controls (16.9 +/- 2.5) (p less than 0.01), but there was no significant difference between the patients with hypertrophic cardiomyopathy (28.0 +/- 3.7) and the controls. (4) The values of the ratio significantly correlated with those of peak circumferential wall stress (r = 0.53, p less than 0.005). These results suggest that atrial/fetal light chain 1 is expressed in the left ventricles in response to the increased hemodynamic load.