Masahito Kajiya

Early eicosapentaenoic acid treatment after percutaneous coronary intervention reduces acute inflammatory responses and ventricular arrhythmias in patients with acute myocardial infarction: A randomized, controlled study

OBJECTIVE We examined whether early loading of eicosapentaenoic acid (EPA) reduces clinical adverse events by 1 month, accompanied by a decrease in C-reactive protein (CRP) values in patients with acute myocardial infarction (MI). BACKGROUND Acute MI triggers an inflammatory reaction, which plays an important role in myocardial injury. EPA could attenuate the inflammatory response. METHODS This prospective, open-label, blinded endpoint, randomized trial consisted of 115 patients with acute MI. They were randomly assigned to the EPA group (57 patients) and the control group (58 patients). After percutaneous coronary intervention (PCI), 1800 mg/day of EPA was initiated within 24h. The primary endpoint was composite events, including cardiac death, stroke, re-infarction, ventricular arrhythmias, and paroxysmal atrial fibrillation within 1 month. RESULTS Administration of EPA significantly reduced the primary endpoint within 1 month (10.5 vs 29.3%, p=0.01), especially the incidence of ventricular arrhythmias (7.0 vs 20.6%, p=0.03). Peak CRP values after PCI in the EPA group were significantly lower than those in the control group (median [interquartile range], 8.2 [5.6-10.2] mg/dl vs 9.7 [7.6-13.9] mg/dl, p<0.01). Logistic regression analysis showed that EPA use was an independent factor related to ventricular arrhythmia until 1 month, with an odds ratio of 0.29 (95% confidence interval, 0.09 to 0.96, p=0.04). CONCLUSIONS Early EPA treatment after PCI in the acute stage of MI reduces the incidence of ventricular arrhythmias, and lowers CRP values.

Early initiation of eicosapentaenoic acid and statin treatment is associated with better clinical outcomes than statin alone in patients with acute coronary syndromes: 1-year outcomes of a randomized controlled study.

BACKGROUND Early initiation of EPA treatment in combination with a statin within 24h after percutaneous coronary intervention (PCI) in patients with acute myocardial infarction (MI) reduces inflammation and ventricular arrhythmia compared with statin monotherapy; however, the impact of early initiation of EPA treatment on cardiovascular events is unclear. We determined whether early eicosapentaenoic acid (EPA) treatment in patients with acute coronary syndrome (ACS) reduces adverse cardiovascular events. METHODS This prospective, open-label, blind end point-randomized trial consisted of 241 patients with ACS. Patients were randomly assigned to receive pitavastatin (2mg/day) with or without 1800mg/day of EPA initiated within 24h after PCI. The primary endpoint was defined as cardiovascular events occurring within 1year, including death from a cardiovascular cause, nonfatal stroke, nonfatal MI and revascularization. RESULTS The mean EPA/arachidonic acid ratio at follow-up was 0.40 in the control group and 1.15 in the EPA group. A primary endpoint event occurred in 11 patients (9.2%) in the EPA group and 24 patients (20.2%) in the control group (absolute risk reduction, 11.0%; hazard ratio, 0.42; 95% confidence interval, 0.21 to 0.87; P=0.02). Notably, death from a cardiovascular cause at 1year was significantly lower in the EPA group than in the control group (0.8% vs. 4.2%, P=0.04). CONCLUSIONS Early initiation of treatment with EPA combined with statin after successful primary PCI reduced cardiovascular events after ACS. CLINICAL TRIAL REGISTRATION UMIN Clinical Trials Registry (UMIN-CTR); Registry Number, UMIN000016723; URL, http://www.umin.ac.jp/ctr/index-j.htm.

Coronary microcirculation in the beating heart

The phase opposition of velocity waveforms between coronary arteries (predominantly diastolic) and veins (systolic) is the most prominent characteristic of coronary hemodynamics. This unique arterial and venous flow patterns indicate the importance of intramyocardial capacitance vessels and variable resistance vessels during a cardiac cycle. It was shown that during diastole the intramyocardial capacitance vessels have two functional components, unstressed volume and ordinary capacitance. Unstressed volume is defined as the volume of blood in a vessel at zero transmural pressure. In vivo observation of systolic narrowing of arterioles in mid-wall and in subendocardium indicates the increase in resistance by cardiac contraction.

Low serum level of secreted frizzled-related protein 5, an anti-inflammatory adipokine, is associated with coronary artery disease.

OBJECTIVE Secreted frizzled-related protein 5 (SFRP5) is an anti-inflammatory adipokine that is associated with insulin resistance in animals. To extend these observations to humans, we investigated the association of serum SFRP5 levels in subjects with and without coronary artery disease (CAD). METHODS Subjects (n=185, 68±11 years, 79% male) suspected of having CAD were enrolled in the study and were divided into two groups, CAD and non-CAD subjects, according to the results of their coronary angiographies. Serum SFRP5 levels of the subjects were measured by an enzyme-linked immunosorbent assay. RESULTS The serum SFRP5 levels in the subjects with CAD were significantly lower than those in the non-CAD subjects (median [interquartile range]: 47.7 [26.6] vs. 52.4 [29.6] ng/mL, respectively; p=0.02). The serum SFRP5 levels significantly correlated with body mass index, the homeostasis model of assessment of insulin resistance, adiponectin levels, and CAD severity. Multivariate logistic regression analysis revealed that a decreased serum SFRP5 level (log transformed) was independently associated with CAD for all subjects (adjusted odds ratio, 0.36; 95% confidence interval, 0.14-0.94; p=0.03). CONCLUSION Serum SFRP5 levels are significantly associated with CAD in humans, suggesting that low SFRP5 levels may contribute to CAD.

Elevated serum adipocyte fatty acid-binding protein concentrations are independently associated with renal dysfunction in patients with stable angina pectoris

BackgroundChronic kidney disease (CKD) is associated with cardiovascular events. Adipocyte fatty acid-binding protein (A-FABP) plays an important role in atherosclerosis. We investigated whether plasma A-FABP is involved in renal function in patients with stable angina pectoris.MethodsA total of 221 patients with significant coronary artery stenosis were enrolled after coronary angiography. CKD was defined as an estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73 m2. The severity of coronary stenosis was assessed using a modified Gensini score and coronary angiography. Serum A-FABP levels were determined by enzyme-linked immunosorbent assay.ResultsSerum A-FABP levels were significantly correlated with both eGFR (r = -0.41, p < 0.01) and the severity of coronary artery stenosis (r = 0.16, p = 0.02), and these relationships remained significant after adjusting for confounding factors. The prevalence of CKD and multi-vessel disease was significantly higher among patients with serum A-FABP levels above the median value of 20.3 ng/ml than among patients with serum A-FABP levels below the median value (57% vs. 27%, p < 0.01 and 64% vs. 48%, p = 0.02, respectively). Multivariate analysis revealed that the presence of three-vessel disease in comparison with single-vessel disease was independently associated with the higher A-FABP (per doubling) (odds ratio; 2.26, 95% confidential interval; 1.28-3.98, p < 0.01) and tended to be associated with the lower eGFR (p = 0.06).ConclusionSerum A-FABP may have a significant role in the interplay between renal dysfunction and coronary atherosclerosis.

Increased Pulmonary Heme Oxygenase-1 and δ-Aminolevulinate Synthase Expression in Monocrotaline-Induced Pulmonary Hypertension

Monocrotaline (MCT), a pyrrolizidine alkaloid plant toxin, is known to cause pulmonary hypertension (PH) in rats. Recent findings suggest that pulmonary inflammation may play a significant role in the pathogenesis in MCT-induced PH. Heme oxygenase-1 (HO-1), the rate-limiting enzyme in heme catabolism, is known to be induced by various oxidative stresses, including inflammation and free heme, and its induction is thought essential in the protection against oxidative tissue injuries. In this study, we examined expression of HO-1 as well as non-specific delta-aminolevulinate synthase (ALAS1), the rate-limiting enzyme in heme catabolism and biosynthesis, respectively, in a rat model of PH produced by subcutaneous injection of MCT (60 mg/kg). MCT treatment caused infiltration of inflammatory cells, fibrosis of the interstitium, and pulmonary arterial wall thickening with marked elevation of right ventricular (RV) pressure, which are characteristics of MCT-induced PH. Gene expression of tumor necrosis factor-alpha (TNF-alpha) as well as DNA binding activity of nuclear factor-kappaB (NF-kappaB) increased at 1 week after MCT treatment, reached a maximum at 2 weeks, and then decreased to the pretreatment level at 3 weeks. HO-1 expression was markedly increased at 1 week, and continued to increase by 3 weeks following MCT treatment, both at transcriptional and protein levels in the mononuclear cells in the lung. ALAS1 mRNA levels in the lung also significantly increased at 2 weeks after MCT treatment. These findings suggest that pulmonary HO-1 expression was presumably induced by proinflammatory cytokine(s) in MCT-treated rats, resulting in the derepression of heme-repressible ALAS1 expression, and that HO-1 induction plays a significant role as an inflammatory factor in this condition.

Serum adipocyte fatty acid-binding protein is independently associated with complex coronary lesions in patients with stable coronary artery disease

The association between circulating adipocyte fatty acid-binding protein (A-FABP) levels and coronary artery disease (CAD) is reported. We assessed whether plasma A-FABP levels are associated with angiographic coronary lesion morphology in patients with stable CAD. Serum A-FABP levels were analyzed in 115 patients with stable CAD (mean age 69 ± 10 years; 80 % men). These patients were angiographically studied and divided into two groups: simple lesions (n = 34) and complex lesions (n = 81). We also compared 50 age- and gender-matched controls with no evidence of CAD. Serum A-FABP levels in patients with stable CAD were significantly higher than those in controls. In patients with stable CAD, serum A-FABP levels were significantly higher in patients with complex lesions than in those with simple lesions: median (25th–75th percentile), 23.4 (17.7–30.8) vs 18.2 (12.2–24.7) ng/ml, P < 0.01. Serum A-FABP levels were also significantly associated with angiographic scores of extent of coronary lesion (r = 0.21, P = 0.02). Multiple logistic analysis that included dyslipidemia, statin therapy, and extent score demonstrated that serum A-FABP was independently associated with complex lesions. The multiple adjusted odds ratio for a complex lesion with a serum A-FABP level (per doubling) was 2.38 (95 % confidence interval, 1.03–6.41; P = 0.03). High serum A-FABP levels were significantly associated with complex coronary lesions in patients with stable CAD, suggesting that high A-FABP levels may be involved in coronary plaque vulnerability.

PHYSIOMIC APPROACH TO BIOMECHANICS OF CORONARY MICROCIRCULATION

The recently proposed Physiome is considered as a powerful successor to the Genome. The definition of Physiome is the quantitative description of the physiological dynamics or functions of the intact organism. The physiome includes integration of knowledge through functional modules of hierarchical system elements of biological systems, and modeling. Biomechanics will offer potent tools to promote the Physiome. By using modern microvisualization technology with physiomic model, this manuscript introduces our physiomic approach to coronary microcirculation which supplies oxygen and nutrients to heart muscles; 1. Mechanical interaction between coronary blood flow and cardiac contraction, and 2. Capillary network and its function.

EARLY LOADING OF OMEGA-3 FATTY ACIDS DECREASES INFLAMMATION AND IN-HOSPITAL EVENTS IN PATIENTS WITH ACUTE MYOCARDIAL INFARCTION UNDERGOING PERCUTANEOUS CORONARY INTERVENTION

GISSI prevention trial demonstrated that long term assumption of omega-3 fatty acids improves significantly the prognosis of patients with a history of myocardial infarction (MI), mainly due to anti-arrhythmic effects. However, the acute effect of omega-3 fatty acids especially on arrhythmic events