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Since low voltage area (LVA) impairs not only intra atrial conduction velocity but also intra atrial propagate direction, these alternates may reflect the P wave duration (PWD) and morphology. We examined the relationship between the PWD, morphology and LVA.Consecutive 127 AF patients were divided into 2 groups depending on the presence of LVA (35 subjects LVA positive group, 92 subjects LVA negative group). P wave morphologies were divided into 3 categories, normal: P-wave duration120 ms, partial interatrial block (IAB): P wave duration≥120 ms, advanced IAB: PWD ≥ 120 ms with biphasic P waves in inferior leads. LVA was defined as a voltage amplitude0.5 mV, and qualitatively assessed to be categorized into three grades (mild10%, 10% ≤ moderate30%, 30% ≤ extensive).LVA was significantly highly detected in patients of advanced age, female, comorbidities of hypertension, prior brain infarction, LA enlargement. PWD was correlated with LA volume in the LVA negative group, but not in the LVA positive group. Advanced IAB was significantly accumulated in the LVA positive group while partial IAB was found in both LVA positive and negative groups. Receiver-operating characteristics curve revealed that a combination of IAB and biphasic P wave in any inferior lead identified the presence of LVA with 83% sensitivity and 98% specificity. PWD and the presence of advanced IAB were independent predictors of LVA as determined by multivariate logistic regression analysis.Advanced IAB is a favorable parameter for the presence of LVA.

Background: Both contact force monitoring (CFM) and unipolar signal modification (USM) are guides for ablation, which improve the efficacy of pulmonary vein isolation of atrial fibrillation. We sought to compare the outcomes of atrial fibrillation ablation guided by CFM or USM. Methods: A total of 136 patients with paroxysmal atrial fibrillation underwent a circumferential pulmonary vein isolation using CF sensing ablation catheters and were randomly assigned to undergo catheter ablation guided by either CFM (CFM-guided group: n=70) or USM (USM-guided group: n=66). In the USM-guided group, each radiofrequency application lasted until the development of completely positive unipolar electrograms. In the CFM-guided group, a CF of 20 g (range, 10–30 g) and minimum force-time integral of 400 g were the targets for each radiofrequency application. The primary end point was freedom from any atrial tachyarrhythmia recurrence without antiarrhythmic drugs at 12-months of follow-up. Results: The cumulative freedom from recurrences at 12-months was 85% in the USM-guided group and 70% in the CFM-guided group ( P =0.031). The incidence of time-dependent and ATP-provoked early electrical reconnections between the left atrium and PVs, procedural time, fluoroscopic time, and average force-time integral, did not significantly differ between the 2 groups. The radiofrequency time for the pulmonary vein isolation was shorter in the USM-guided group than CFM-guided group but was not statistically significant ( P =0.077). Conclusions: USM was superior to CFM as an end point for radiofrequency energy deliveries during the pulmonary vein isolation in patients with paroxysmal atrial fibrillation in terms of the 12-month recurrence-free rate. Clinical Trial Registration: URL: https://www.umin.ac.jp/ctr/index.htm . Unique identifier: UMIN000021127.

Water-soluble copolymers such as polyvinylpyrrolidone and polyvinyl alcohol have been widely used as detergents, paints, and chemical intermediates in many industrial processes, leading to environmental concerns associated with high-volume organic compound wastewater. Therefore, in this study, a combined upflow anaerobic sludge blanket (UASB) reactor and downflow hanging sponge (DHS) biosystem has been applied for the treatment of synthetic water-soluble copolymer wastewater. Copolymer consisted of ethylene glycol and propylene glycol with a total molecular weight of 8,500, commonly preferred in the automobile parts processing factory, were included in influent. Overall, the whole UASB–DHS system achieved a favorable chemical oxygen demand (COD) removal efficiency of 86% ± 7%. In more detail, with an organic loading rate of 2.12 kg-COD ⋅ m−3 ⋅ day −1, the UASB reactor enhanced the biodegradability of wastewater, and reached COD removal efficiency of 61% ± 16%. Meanwhile, gel permeation chromatography analysis indicated that the molecular weight of the wastewater was primarily reduced in the DHS reactor. In addition, massive 16S rRNA gene sequencing showed that polyethylene-glycol-degrading bacteria Pelobacter sp. was predominant in the UASB granular sludge.

Decelerated fermentation of natural rubber latex was performed to investigate the relationship between the morphology and mechanical properties of natural rubber. Natural rubber latex was preserved with sodium hydroxymethylglycinate, as a bactericide, to decelerate the fermentation of nonrubber components such as proteins, phospholipids, carbohydrate, and so forth. Gradual increases in the viscosity of the latex and gel content of the resulting rubber took place as the preservation period was prolonged, which were distinguished from less change in the viscosity of high-ammonia natural rubber (HANR) and high gel content of its rubber. The particle size distribution was dramatically changed during decelerated fermentation, although that of the HANR latex did not change. The pH and nitrogen content of the rubbers were independent of the preservation time. Morphology of the fermented natural rubber and the HANR was observed with scanning probe microscopy. Fewer mechanical properties of the fermented natural rubber were related to the destruction of the nanomatrix structure of the nonrubber components, which resulted from the decrease in the fatty acid ester groups with bacteria as compared with the good mechanical properties of the HANR.

Background: Although J-waves are seen in both patients with idiopathic ventricular fibrillation (IVF) and the general population, their genesis remains unclear. To assess the relationship between J-waves and autonomic tone we investigated the circadian variation of J-waves in individuals with and without IVF. Methods and Results: In study 1, we obtained resting 12-lead ECG and Holter ECG recordings in 258 individuals undergoing screening for heart disease. In 60 of these subjects (23.3%), we detected J-waves on Holter ECGs; 40 of them (66.7%) had shown no J-waves on 12-lead ECGs. In study 2, we measured the J-wave amplitude, heart rate (HR), and HR variability [high frequency (HF) and the ratio of low- to high-frequency (LF/HF)] on Holter ECGs recorded in 5 patients with IVF and 20 control subjects who had manifested J-waves. The J-wave amplitude increased at night and decreased during the day in both groups; it was significantly higher in the IVF patients (P

We describe a case with a focal atrial tachycardia (AT) masquerading as perimitral atrial flutter revealed after circumferential pulmonary vein antral isolation for atrial fibrillation. It was successfully terminated and became noninducible by a point ablation on the left atrial anterior wall (LAAW) near the mitral annulus in contact with the aortic root and on the left superior pulmonary vein-left atrial appendage ridge, without any linear ablation, using electroanatomical mapping and conventional precise mapping with a maximum amplified gain within the low-voltage area. The AT revealed in our case was an LAAW-aorta contiguity area-related AT.

The false tendons (FTs) are fibromuscular bands that transverse the left ventricular cavity and often contain conduction tissue, suggesting that FTs may contribute to the occurrence of ventricular arrhythmias. The presence of J waves is associated with vulnerability to ventricular arrhythmias; however, the mechanisms underlying the manifestation of J waves remain to be elucidated.To investigate the electrocardiographic characteristics, including the presence of J waves, in patients with FTs.We studied 44 patients with distinct FTs detected by echocardiography (FT group) and 88 age- and sex-matched healthy subjects without FTs (control group). The PQ, QRS, JT, QT, corrected JT, and corrected QT intervals were automatically measured on surface 12-lead electrocardiograms, and the presence or absence of J waves was also determined. J waves were defined as terminal QRS notching or slurring. FTs were classified according to their points of attachment as type 1 (longitudinal, 52%), type 2 (diagonal, 25%), type 3 (transverse, 16%), and type 4 (weblike, 7%).QRS and corrected QT intervals were significantly longer in the FT group than in the control group (P.005 and P.05, respectively). The incidence of J waves was significantly higher in the FT group (64%) than in the control group (19%) (P.0001). J waves were more prevalent in type 1 (78%) and type 2 (73%) than in type 3 (14%) and 4 FTs (33%) (P0.05) and in patients with thick FTs (≥ 2 mm) than with thinner FTs (2 mm) (71% vs 33%; P.05). The J-wave location differed according to the FT type.Our results suggest that FTs may carry a certain role to the genesis of J waves.

Low temperature degradation of natural rubber was performed with potassium persulfate (K 2 S 2 O 8 , KPS) in the latex stage at 30 °C to accomplish a good processability of the rubber. Various grades of natural rubbers were used as a source rubber. Gel content, molecular weight and chemical structure of the rubbers were characterized by swelling method, size exclusion chromatography and 1 H NMR spectroscopy, respectively. The well characterized natural rubber was subjected to oxidative degradation with KPS at 30 °C. Mooney viscosity decreased when the latex was degraded with 1.0 phr of KPS and it was dependent upon the amount of KPS. Molecular weight and gel content of the degraded natural rubber were about one-half as low as those of the source rubber. Chemical structure of the rubber was analyzed through Fourier transform infrared and 1 H NMR spectroscopic methods. The degraded natural rubber was found to contain carbonyl and formyl groups as an evidence of the oxidative degradation. Tensile strength of a vulcanizate prepared from the degraded natural rubber was the same as that prepared from the source rubber, even though the gel content and the molecular weight of the degraded rubber were distinguished from those of the source rubber.

Background: Cardiac autonomic dysfunction is associated with a poor prognosis in patients with heart failure (HF). Systemic inflammation is elevated in patients with HF. We hypothesized that cardiac resynchronization therapy (CRT) improves cardiac sympathetic nervous dysfunction and systemic inflammation. To test our hypothesis, we evaluated cardiac sympathetic activity and serum levels of high sensitive C-reactive protein (hs-CRP) before and after CRT. Methods: Twenty-seven patients with chronic HF (19 men, eight women; mean age 67 ± 10 years) with nonischemic cardiomyopathy who underwent CRT were evaluated. Each patient was evaluated before and 6 months after CRT. Responders were defined as patients showing ≥15% absolute decrease in left ventricular end-systolic volume. Cardiac sympathetic activity was estimated with cardiac 123I-metaiodobenzylguanidine (MIBG) scintigrams. Results: Patients were categorized as responders (n = 19) and nonresponders (n = 8) according to echocardiographic findings. In responders, the mean heart-to-mediastinum (H/M) ratio at the delayed phase in cardiac 123I-MIBG scintigraphic findings was significantly increased (P

Background: Inflammatory processes are involved in the pathogenesis of atrial fibrillation (AF).Objective: The purpose of this study was to test the hypothesis that atrial fibrosis and enhanced vulnerability to AF evoked by pressure overload can be attenuated by pioglitazone, a peroxisome proliferator-activated receptor-γ agonist, via suppression of inflammatory profibrotic signals.Methods: Male Sprague-Dawley rats were subjected to abdominal aortic constriction (AAC). Pioglitazone 3 mg/kg/day or vehicle was orally administered for 4 weeks.Results: Western blot analysis revealed that AAC enhanced expression of monocyte chemoattractant protein (MCP)-1, transforming growth factor-β1 and α-smooth muscle actin in the left atrium (LA), which was suppressed by pioglitazone. Messenger RNA expression of collagen type 1 and atrial natriuretic peptide in the LA was increased by AAC, which was suppressed by pioglitazone. Gelatin zymography demonstrated that activity of matrix metalloproteinase-9 was increased by AAC, which was suppressed by pioglitazone. Pioglitazone attenuated AAC-induced LA fibrosis. In isolated-perfused heart experiments, AAC did not alter the refractory period of the LA or the right atrium (RA), but it did prolong the interatrial conduction time. Programmed extrastimuli from the RA induced AF in all of the AAC-treated rats (8/8 [100%]). This was suppressed by pioglitazone (2/8 [25%], P

Formation of photoreactive nanomatrix structure was investigated by graft copolymerization of an inclusion complex of 1,9-nonandiol dimethacrylate (NDMA) with β-cyclodextrin (β-CD) onto natural rubber particle using potassium persulfate (KPS), tert-butyl hydroperoxide/tetraethylenepentamine (TBHPO/TEPA), cumene hydroperoxide /tetraethylenepentamine (CHPO/TEPA), and benzoyl peroxide (BPO) as an initiator. The graft copolymer was characterized by 1H-NMR and FT-IR after coagulation. The conversion of NDMA and the amount of residual methacryloyl group was found to be 58.5 w/w% and 1.81 w/w%, respectively, under the suitable condition of the graft copolymerization. The morphology of the film specimen, prepared from the graft copolymer, was observed by transmission electron microscopy (TEM) after staining the film with OsO4. Natural rubber particle of about 1.0 μm in diameter was dispersed in poly(NDMA) matrix of about 10 nm in thickness.

Background: Cardiovascular autonomic neuropathy is a major complication in patients with diabetes mellitus (DM). However, the relationship between cardiovascular autonomic neuropathy and the incidence of cardiovascular events has been poorly investigated in type 2 DM. The present study aimed to assess the long-term cardiovascular predictive value of baroreflex sensitivity (BRS) in Japanese patients with type 2 DM without structural heart disease. Methods and Results: BRS was evaluated using the phenylephrine method in 210 patients with type 2 DM who did not have structural heart disease or other severe complications. BRS was considered depressed if

Photoreactive particle was prepared by graft copolymerization of 1,9-non-andioldimethacrylate (NDMA) onto deproteinized natural rubber (DPNR) particles in latex stage. First, NDMA was mixed with α-cyclodextrin (α-CD) as a coupling agent to form an inclusion complex to stabilize a carbon―carbon double bond of NDMA as a bifunctional monomer. Second, the inclusion complex was graft-copolymerized onto natural rubber (NR) in latex stage with potassium persulfate (KPS) as an initiator, after deproteinization with urea in the presence of surfactant. A terminal vinyl group of NDMA was used for the graft copolymerization, while the other remained in the resulting polymer, due to the coupling effect of the α-CD. The products, after washing α-CD out, were characterized by FTIR, X-ray diffraction (XRD), 1 H NMR and solid-state 13 C NMR measurements. The amount of residual carbon―carbon double bond after graft copolymerization was investigated in relation to the amount of rubber and reaction temperature.

We report a case of selenium deficiency in a patient with Crohn's disease on long-term total parenteral nutrition (TPN). She manifested lassitude of the legs, discoloration of the nail beds, and macrocytosis. Since her plasma selenium level was found to be below the measurable level, we diagnosed this case as selenium deficiency. After intravenous administration of sodium selenite, her symptoms were reversed. Careful attention should be paid to selenium deficiency when a patient receives long-term TPN; supplementary administration of selenium via TPN may be required because selenium is often not routinely added to TPN formulations.

Little is known about the outcome of catheter ablation of atrial fibrillation (AF) in patients with heart failure (HF) and a severely reduced left ventricular ejection fraction (LVEF). We aimed to clarify the effectiveness of catheter ablation of AF in patients with a severely low LVEF. This retrospective study included 18 consecutive patients with HF and an LVEF of ≤35 % who underwent catheter ablation of AF. We investigated the clinical parameters, echocardiographic parameters and the incidence of hospitalizations for HF. During a median follow-up of 21 months (IQR, 13–40) after the final procedure (9 with repeat procedures), 11 patients (61 %) maintained sinus rhythm (SR) (6 with amiodarone). The LVEF and NYHA class significantly improved at 6 months after the CA in 12 patients (67 %) who were in SR or had recurrent paroxysmal AF (from 25.8 ± 6.3 to 37.0 ± 11.7 %, P = 0.02, and from 2.3 ± 0.5 to 1.5 ± 0.7, P < 0.01, respectively) but not in patients who experienced recurrent persistent AF. The patients with SR or recurrent paroxysmal AF had significantly fewer hospitalizations for HF than those with recurrent persistent AF after the AF ablation (log-rank test; P < 0.01). Catheter ablation of AF improved the clinical status in patients with an LVEF of ≤35 %. A repeat ablation procedure and amiodarone were often necessary to obtain a favorable outcome.

To explore a novel strategy of preventing atrial fibrosis and atrial fibrillation (AF), we have established 3 appropriate experimental models of AF. Firstly, atrial fibrosis was induced by pressure overload by abdominal aortic constriction (AAC). AAC enhanced left atrial (LA) expression of monocyte chemoattractant protein-1. Scanning electron microscopy revealed that LA endothelial cells were irregularly hypertrophied, with disarrangement of lines of cells. Possible "arrested" leukocyte-derived cells were observed on the surface of LA endothelial cells. Treatment with pioglitazone, a peroxisome proliferator-activated receptor-γ agonist, resulted in attenuation of pressure overload-induced LA fibrosis. Secondly, LA fibrosis was induced by continuous infusion of angiotensin II (AII). Repeated whole-body hyperthermia led to the induction of heat shock protein (HSP) 72, which resulted in attenuation of AII-induced LA fibrosis. Thirdly, atrial fibrosis was induced by 5/6 nephrectomy as a model of AF associated with chronic kidney disease. Because the amount of nicotinamide adenine dinucleotide phosphate oxidase was increased and the potent antioxidant agent was effective, oxidative stress may be involved in the pathogenesis of LA fibrosis and enhanced AF vulnerability in this model. These observations suggest that inflammatory profibrotic processes are essential for the development of atrial fibrosis in these 3 models. Pioglitazone, induction of HSPs and antioxidant agent could be novel therapeutic approaches to preventing atrial fibrosis and AF.

Anionic polymerizations of 2-[(trimethylsilyl)oxy]ethyl methacrylate (1), 2-[(tert-butyldimethylsilyl)oxy]ethyl methacrylate (2), and 2-[(methoxymethyl)oxy]ethyl methacrylate (3), the protected forms of 2-hydroxyethyl methacrylate (HEMA), were carried out in THF at −78°C with 1,1-diphenylhexyllithium or 1,1-diphenyl-3-methylpentyllithium in the presence of LiCl. The resulting poly(1–3)s were found to possess predictable molecular weights and very narrow molecular weight distributions. The sequential polymerizations of tert-butyl methacrylate with the anionic propagating ends of poly(1–3) gave block copolymers in quantitative efficiency. Thus, the anionic polymerizations of 1–3 proceeded without transfer and termination reactions to afford stable living polymers. Complete hydrolysis of the protective groups of poly(1–3)s produced linear poly(HEMA) quantitatively. Novel well-defined di- and triblock copolymers containing hydrophobic [polystyrene, poly(4-octylstyrene), polyisoprene] and hydrophilic segments [poly(HEMA)] were also prepared by sequential polymerization of the corresponding hydrophobic comonomers with 1, followed by deprotection.

Background: Cardiovascular autonomic neuropathy is a major complication in patients with diabetes mellitus (DM), and baroreflex sensitivity (BRS) reportedly can predict cardiovascular prognosis in type 2 DM patients. The hypothesis that cardiovascular events are associated with gender differences in BRS was tested in the present study. Methods and Results: From 1998, we have evaluated BRS by phenylephrine methods in 185 consecutive type 2 DM patients. The long-term prognostic value of BRS was compared between 91 female (5812 years) and 94 male patients (5811 years). There was no significant difference in age or severity and duration of DM between the 2 groups. When compared to male, the BRS value in female patients was significantly lower (9.266.0 vs. 5.975.0ms/mmHg, P

The angiotensin II receptor blocker (ARB) telmisartan has been shown to activate peroxisome proliferator-activated receptor γ and increase adiponectin protein content in adipocytes. We tested the hypothesis that telmisartan can increase the serum level of adiponectin and improve insulin resistance.The study participants were 25 consecutive hypertensive patients (8 females, 17 males; 65 ± 10 years). Insulin resistance was defined as a patient showing ≥2.5 in the homeostasis model assessment (HOMA) index. We divided subjects into non-insulin resistance (n = 10) and insulin resistance groups (n = 15) based on the HOMA index. Telmisartan was administered (40 mg/day) was administered for 24 weeks.In the insulin resistance group, telmisartan treatment resulted in a significant decrease in the HOMA index and serum level of C-reactive protein, and it increased the serum level of adiponectin (P0.05, respectively). Such improvements were not observed in the non-insulin resistance group. Stepwise multiple regression analysis showed that the increase in the serum level of adiponectin was independently associated with reduction in the HOMA index.Our findings suggest that telmisartan improves insulin resistance that parallels an increase in the serum level of adiponectin in hypertensive patients with insulin resistance. It may therefore have advantages in treating such populations.

Atrial fibrillation (AF) is the commonest arrhythmia. Studies have shown that atrial tachypacing (artificial persistent AF) causes electrical remodelling. This is characterised by the shortening of the atrial effective refractory period (ERP), in which reduction in L-type Ca(2+) channel current plays an essential part. Atrial fibrosis, a feature of structural remodelling, is induced by continuous infusion of angiotensin II, and has been associated with conduction delay in atria, which promotes AF. Acute atrial ischaemia, frequently observed during development of acute coronary syndrome, has been associated with atrial conduction heterogeneity, which also promotes AF. Induction of heat shock proteins (Hsp72 and Hsp27) by hyperthermia and/or geranylgeranylacetone has demonstrated to protect the heart against such atrial remodelling. The potent protective role of Hsp72 and Hsp27 against clinical AF in patients who underwent open heart surgery has been shown. Taken together, interventions that induce heat shock responses (including induction of Hsp72 and Hsp27) may prevent newly developed AF and delay the progression of paroxysmal AF to persistent AF.

It has been shown that orally administered geranylgeranylacetone (GGA), an anti-ulcer drug, induces expression of heat shock protein 72 (HSP72) and provides protection against ischemia-reperfusion in rat hearts. The underlying protective mechanisms, however, remain unknown. Mitochondria have been shown to be a selective target for heat stress-induced cardioprotection. Therefore, we hypothesized that preservation of mitochondrial function, owing to an opening of a putative channel in the inner mitochondrial membrane, the mitochondrial ATP-sensitive potassium (mitoKATP) channel, could be involved in GGA- or heat stress-induced cardioprotection against ischemia-reperfusion. Rats were treated with oral GGA or vehicle. Twenty-four hours later, each heart was isolated and perfused with a Langendorff apparatus. GGA-treated hearts showed better functional recovery, and less creatine kinase was released during a 30-min reperfusion period, after 20 min of no-flow ischemia. Concomitant perfusion with 5-hydroxydecanoate (5-HD, 100 μM) or glibenclamide (10 μM) abolished the GGA-induced cardioprotective effect. GGA also showed preserved mitochondrial respiratory function, isolated at the end of the reperfusion period, which was abolished with 5-HD treatment. GGA prevented destruction of the mitochondrial structure by ischemia-reperfusion, as shown by electron microscopy. In cultured cardiomyocytes, GGA induced HSP72 expression and resulted in less damage to cells, including less apoptosis in response to hypoxia-reoxygenation. Treatment with 5-HD abolished the GGA-induced cardioprotective effects but did not affect HSP72 expression. Our results indicate that preserved mitochondrial respiratory function, owing to GGA-induced HSP72 expression, may, at least in part, have a role in cardioprotection against ischemia-reperfusion. These processes may involve opening of the mitoKATP channel.

We tested the hypothesis that atrial fibrosis and atrial fibrillation (AF) evoked by angiotensin II (AII) could be prevented by the induction of heat-shock protein 72 (HSP72) by hyperthermia (HT). In cultured atrial fibroblasts isolated from male Sprague-Dawley rats, HT (42 degrees C) was applied for 30 min. AII (100 nmol/L) was added to the medium 8 h later. HT induced the expression of HSP72, which was associated with the attenuation of AII-induced extracellular signal-regulated kinase (ERK1/ERK2) phosphorylation, alpha-smooth muscle actin (alpha-SMA) expression, transforming growth factor-beta(1) secretion, collagen synthesis, and expression of collagen type I and tissue inhibitor of metalloproteinases-1. A small interfering RNA targeting HSP72 abolished these anti-fibrotic effects of HT. In male Sprague-Dawley rats in vivo, an osmotic mini-pump was subcutaneously implanted for continuous infusion of AII (400 ng/kg/min). Whole-body HT (43 degrees C, 20 min) was applied 24 h before and 7, 14, and 21 days after the start of the AII infusion. Repeated HT led to the induction of HSP72 expression, which resulted in an attenuation of AII-induced left atrial fibrosis. In an electrophysiological study using isolated perfused heart, continuous AII caused slowing of interatrial conduction without affecting atrial refractoriness. In AII-treated hearts, extrastimuli from the right atrial appendage resulted in a high incidence of repetitive atrial responses, which were suppressed by treatment with HT. Our results suggest that HT treatment is effective in suppressing AII-mediated atrial fibrosis and AF via induction of HSP72 at least in parts, and is thus expected to be a novel strategy for prevention of AF.

We investigated the effects of insulin resistance on the expression of heat-shock proteins (HSPs) and myocardial protection against ischemia/reperfusion injury. Male Sprague-Dawley rats received normal chow (CNT) or high-fat (HiF) diet. HiF diet for 6 weeks resulted in the development of insulin resistance, which was evaluated by oral glucose test and insulin tolerance test. Twenty-four hour after oral administration of geranylgeranylacetone (GGA) (200 mg/kg), the heart was isolated and perfused retrogradely with two different doses of insulin (0.1 or 1 mU/ml). Myocardial expression of HSP72 was examined using Western blot analysis. In the HiF group, the expression of HSP72 in response to GGA was decreased. The recovery of left ventricular developed pressure (LVDP) 30 min after reperfusion was tended to be lower in HiF group than in CNT group. Although GGA improved the recovery of LVDP in both CNT and HiF rats, LVDP during reperfusion period was significantly lower in HiF group than in CNT group. High-dose insulin perfusion caused deterioration of post-ischemic functional recovery and LVDP was not different between the two groups, but GGA-induced cardioprotection was preserved irrespective of the dose of insulin both in the CNT and HiF rats. This is the first demonstration that expression of HSP72 was depressed in the heart and that reduced HSP72 was related with less cardioprotection against ischemic insult in high-fat diet-induced insulin resistance rats.

Introduction: We compared the effectiveness of left ventricular (LV) only pacing with standard biventricular (BiV) pacing by a novel electrogram-based algorithm for atrioventricular (AV) optimization (SMART-AV®, Boston scientific, Minnesota). Methods: 20 patients with NYHA class ≥2 heart failure, LV ejection fraction (LVEF) ≤35% and QRS duration ≥120 ms were implanted with Cognis® (Boston scientific, Minnesota) for CRT and divided into two groups as follows: LV group (13 patients) with LV only pacing and BiV group (7 patients) with standard BiV pacing by SMART-AV® algorithm. LV volumes and systolic function were assessed with echocardiography at baseline and 6 months. A reduction in LV end systolic volume (LVESV) ≥15% was defined as responder. Results: There were no significant differences in baseline characteristics between LV group and BiV group. Although LVESV was significantly decreased in both groups 6 months after pacing, LVEF was improved only in LV group. Responder was higher in LV group than BiV group but there was no statistical significance (76.9% vs 41.9%, P=0.15). There were also no significant differences in reduction of LVESV and change in LVEF. Conclusion: Left ventricular only pacing for patients with intrinsic AV conduction by SMART-AV® algorithm is effective as well as standard BiV pacing.

Background: Effect of upgrade from permanent right ventricular (RV) apical pacing to biventricular (BiV) pacing has not yet delineated. Aims: The aim of this study is to investigate the role of upgrade from RV pacing to BiV pacing. Methods: Sixty four patients with NYHA>class 2 heart failure and LV ejection fraction (LVEF) 130 msec) and group-B (upgrade to BiV pacing in 24 patients with bradycardia and paced-QRS>150 msec). The LV volume and systolic function were assessed with echocardiography at baseline and 6 months after implantation of a cardiac resynchronization (CRT) device. A reduction in LV end systolic volume (LVESV)>15% was defined as responder. Results: LVESV reduced significantly in group-A (204.7 ml to 181.6 ml, P

Backgrounds: Some specific CRT devices can sense the left ventricular (LV) activation and inhibit the LV pacing to prevent R on T. However, only a little is known about the trouble caused by this function. We experienced some patients who had the persistent inhibition of the LV pacing in the setting of biventricular pacing. Methods: The occurrence of LV pacing inhibition (LPI) was investigated in consecutive 68 patients, who underwent the implantation of CRTDs with LV pacing protection (LVPP) function. LV sensing, LVPP and the RV sense-triggered LV pacing were activated in all the patients. Results: The persistent RV only pacing with the LPI was observed in 5 patients, despite the pacing setting was biventricular (n=4) or LV only (n=1). In 2 patients, the far-field atrial sensing caused the LPI, and one of them had the LV lead dislodgement. In the other 3 patient, oversensed T-wave or automatic prolongation of PVARP following PMT detection, concealed the atrial sensing. and the conducted RV to LV interval became shorter than the LV protection interval, and it caused the persistent LPI. Conclusion: Though the LVPP is useful in avoiding the risk of R on T, it possibly causes the persistent LPI in some specific situation.

Aims: Bacteria culture examinations are important to identify the bacteria and its focus of infection in patients with device infection. The aim of this study was to investigate the relationship between results of culture and clinical symptoms in patients with local pocket infection. Methods and Results: Between January 2005 and June 2010, 42 patients (mean age 61 yr; male n=33) were diagnosed of device infection in our hospital. Twenty four (57%) patients had only local inflammatory changes or erosion at generator-pocket site without blood stream infection and a vegetation-like mass adherent to the leads at initial echocardiological assessment. Among them, 17 (71%) patients had a positive pocket tissue culture. Lead cultures after lead extraction procedure were more frequently positive in patients with positive tissue culture than in patients with negative tissue culture (47% (8/17) vs 29% (2/7)). Additionally, there was no difference in results of pocket tissue culture between patients with and without fistula or discharge at the generator-pocket site. Conclusion: Bacteria culture examinations revealed that pocket infection extended to the leads in about half of patients who had only local inflammatory changes or erosion at generator-pocket site without any signs of systemic infection at initial assessment.

Aims: Venous obstruction following cardiac electronic device implantation sometimes causes a challenge in lead revision or device upgrade. The aim of this study was to determine the predictors of venous obstruction after transvenous device implantation. Methods and Results: Between April 2004 and April 2011, contrast venography was performed in 77 patients who needed lead revision or device upgrade. Sixteen (21%) of them had venous obstruction, including 8 patients with total obstruction and 8 patients with partial obstruction. No significant differences between obstructed and non-obstructed patients were seen for age, sex, atrial fibrillation, dilated cardiomyopathy, numbers of the leads, antiplatelet/anticoagulant drugs, and time from initial implantation to lead revision or device upgrade. In univariate analysis, low body weight and low body surface area (BSA) were associated with an increased risk of venous obstruction (P=0.036, 55.4 vs 62.3 kg, and P=0.035, 1.57 vs 1.68 m2, respectively). Multivariate logistic regression analysis showed that BSA was a predictor of venous obstruction (OR: 0.58, 95% CI: 0.36–0.96, P=0.034). This means 1.7-fold risk of venous obstruction per 0.1 m2 decrease of BSA. Conclusion: The incidence of venous obstruction following cardiovascular electronic device implantation was not rare. In this study, BSA had negative correlation with risk of venous obstruction.

Aim: Transvenous cardiovascular implantable electronic devices (CIEDs) implantation in patients with complex congenital heart disease (CCHD) is challenging because of their complex anatomy. We report our experience of CIEDs implantation in CCHD patients. Methods: CCHD patients underwent the CIEDs implantation, were analyzed retrospectively. Results: We implanted CIEDs (pacemaker n=19, ICD n=5, CRT-D n=2) in consecutive 26 CCHD patients (mean 25 y.o.) from 1994 to 2011. The underlying heart diseases were tricuspid atresia (n=2) and single RV (n=1) both after Fontan operation, single LV (n=1) underwent the septation, truncus arteiosus communis underwent Rastelli (n=1), transposition of great ateries (TGA) (n=9) and corrected TGA (n=12; SLL n=9, IDD n=3). Twelve patients with TGA and corrected TGA underwent atrial switch (n=6) or double switch (n=6) operation. The pacing leads were successfully positioned with favorable sensing and pacing threshold in all patients, transvenously, without major complications. In 2 patients with cTGA, we successfully positioned the leads at the LV apex and in the coronary vein for the resynchronization of anatomical RV. The lead revision was required during the follow-up period, due to the lead dislodgement (n=2) and the lead fracture (n=2). Conclusion: Transvenous implantation of CIEDs was safely performed and feasible even in patients with CCHD and sometimes with atrio-ventricular discordance.

This paper describes an improved sandwich enzyme immunoassay for insulin in human serum. The detection limit was significantly improved from 0·1 mU/L to 0·02 mU/L, by incubation with guinea-pig anti-insulin Fab′-peroxidase conjugate in the presence of normal guinea-pig F(ab′)2 to reduce the non-specific binding of the conjugate. The degree of serum interference was considerably reduced by coating polystyrene balls with acid-treated anti-insulin IgG and by incubating the polystyrene balls with serum samples at a lower temperature for a shorter time. The time for incubation with anti-insulin Fab′-peroxidase conjugate was also shortened. As a result, the volume of serum that could be used increased from 10 μl to 50 μl, and the time for immuno-reactions was reduced from 8 h to 4 h. Applicability of the present improvement to enzyme immunoassay of other antigens in human serum is discussed.

We describe methods for the conjugation of Fab’ to horseradish peroxidase through thiol groups in the hinge of Fab’ using reaction with maleimide groups or the thiol-disulfide exchange reaction [l]. The Fab’-horseradish peroxidase conjugates prepared by these methods were demonstrated to be superior in both sandwich enzyme immunoassay and immunohistochemical staining to conjugates prepared by methods in which the enzyme was conjugated through Fab’ amino groups [l], with detection limits in the attomole range [2]. Hinge conjugation is, however, not suitable for small amounts of affinity-purified Fab’, due to loss of thiol groups during gel filtration and concentration. We describe a micro-scale method for affinity purification after Fab’-peroxidase conjugation and its application to a sandwich enzyme immunoassay of insulin in human serum. The non-specific binding of the affinity-purified conjugate was lowered by gel filtration, and the sensitivity for insulin was 1 nU/tube and 100 nU/ml of serum.

We have experimentally established appropriate models of atrial fibrillation (AF) with atrial interstitial fibrosis. Two approaches were adopted. Firstly, left atrial fibrosis was induced by continuous infusion of angiotensin II (AII). In an electrophysiological study using isolated perfused heart, AF was easily induced following AII treatment. Repeated whole-body hyperthermia led to the induction of heat-shock protein 72, which resulted in attenuation of AII-induced left atrial fibrosis and suppression of AF inducibility. Secondly, atrial fibrosis was induced by pressure overload by abdominal aortic constriction (AAC). AAC enhanced left atrial expression of monocyte chemoattractant protein-1 and activity of matrix metalloproteinase-9. Treatment with pioglitazone, a peroxisome proliferator-activated receptor-γ agonist, resulted in attenuation of pressure overload-induced left atrial fibrosis and suppression of AF inducibility. In the same AAC model, the effects of candesartan on gap junction remodeling were investigated. Connexin 43 (Cx43) of the left atria was firmly located in the intercalated disks in control rats. A progressive redistribution of Cx43 from the intercalated disk to the lateral surface (lateralization) was observed in AAC rats. Candesartan prevented left Cx43 lateralization. Thus, heat-shock proteins, pioglitazone, and candesartan could be novel therapeutic approaches to prevent atrial fibrosis and AF.