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Excessive oxidative stress is considered one of the mechanisms of a decrease in contractile force without concomitant reduction in oxygen cost in failing myocardium. We hypothesized that the antioxidant vitamin C may help reverse hyporesponsiveness to beta-adrenergic stimulation and improve myocardial efficiency in patients with heart failure (HF) after myocardial infarction (MI).Nineteen patients with mild to moderate HF due to previous MI (mean left ventricular [LV] ejection fraction 39%) were instrumented with conductance and coronary sinus thermodilution catheters. Left ventricular contractility, expressed as E(es), the slope of end-systolic pressure-volume relationship, and mechanical efficiency, expressed as the ratio of LV stroke work (SW) to myocardial oxygen consumption (MVO2), were measured in response to the intravenous infusion of dobutamine (4 microg/kg per min) before (Dob) and during (Dob + Vit C) the infusion of vitamin C (2.0-g bolus injection and subsequent 50-mg/min infusion through the jugular vein) (vitamin C group, n = 10). The infusion of vitamin C augmented the E(es) response to dobutamine by 20% +/- 8% (Dob 2.1 +/- 0.3, Dob + Vit C 2.5 +/- 0.4 mm Hg/mL, P.01) and the SW/MVO2 response by 21% +/- 5% (Dob 36% +/- 3%, Dob + Vit C 43% +/- 4%, P.01). In the control group (n = 9), E(es) and SW/MVO2 were measured in response to dobutamine before (Dob) and during (Dob + vehicle) the infusion of saline. No difference in E(es) or SW/MVO2 was observed between Dob and Dob + vehicle (E(es): Dob 2.1 +/- 0.2, Dob + vehicle 2.1 +/- 0.2 mm Hg/mL per square meter, P = nonsignificant) (SW/MVO2: Dob 35% +/- 4%, Dob + vehicle 33% +/- 4%, P = nonsignificant).The administration of the antioxidant vitamin C enhances the contractile response to dobutamine and improves myocardial efficiency in patients with HF.

Objectives This study sought to determine vasomotor functional responses of conduit coronary artery distal to bare-metal stents (BMS), polymer-only stents (POLY), and sirolimus-eluting stents (SES) in a clinically relevant animal model. Background Drug-eluting stents (DES) reduce in-stent restenosis, and also affect neointima formation and vascular remodeling in downstream coronary segments. Whether distal artery vasomotor function is also influenced by DES has not been determined. Methods Pigs (n = 12) received coronary stent implants, and hearts were harvested at 1 month. Arterial segments ≥15 mm distal to stents were excised and studied in an organ-chamber apparatus. Endothelium-dependent and endothelium-independent relaxation and contraction to classical agonists were measured. Results The SES showed increased lumen area and reduced neointima; abnormal vasomotor function of conduit arteries distal to SES also was observed. Contraction to endothelin-1 was significantly enhanced for SES compared with both BMS and POLY. Endothelium-dependent relaxation to a maximal dose of substance P was attenuated for SES compared with both BMS and POLY (46 ± 6% vs. 71 ± 3% and 78 ± 3%, respectively, p l 0.001). Endothelium-independent relaxation to sodium nitroprusside was potentiated for SES, compared with BMS and POLY (100 ± 5% vs. 69 ± 7% and 77 ± 5%, respectively, p = 0.02). Conclusions Stent-based local delivery of sirolimus profoundly inhibited neointima formation but caused vasomotor dysfunction in distal conduit vessel segments. These observations suggest that distal coronary vasospasm may be more readily evoked in the presence of DES and contribute to pathophysiological sequela.

ObjectivesThis study evaluated the efficacy of catheter-based transcoronary myocardial hypothermia (CTMH) in pigs with acute myocardial ischemia.BackgroundAlthough it has been suggested that hypothermia therapy can attenuate myocardial necrosis, few applications have been accepted for clinical use.MethodsThis study comprises 2 substudies. In both studies, pigs underwent 60 min of coronary occlusion and 180 min of reperfusion. In study 1, after 15 min of coronary occlusion with an over-the-wire-type balloon (OTWB), pigs in the hypothermia group (H) (n = 13) were directly infused with 4°C saline into the coronary artery through the OTWB wire lumen (2.5 ml/min) for 60 min. Pigs in the normothermia group (N) (n = 15) received the same amount of 36.5°C saline. In study 2, pigs in the hypothermia-reperfusion group (HR) (n = 5) were infused with 4°C saline through the infusion catheter (8 ml/min) for 30 min with a later start (60 min after coronary occlusion), whereas simple reperfusion was used for the reperfusion group (R) (n = 6).ResultsCatheter-based transcoronary myocardial hypothermia was successful in both studies. In study 1, CTMH significantly decreased ventricular arrhythmia and the ratio of necrosis to ischemic risk area (H: 9 ± 2%; N: 36 ± 4%; p < 0.0001) with a significant reduction of enzyme leaks. In study 2, CTMH tended to reduce the ratio of necrosis (HR: 33 ± 2%; R: 45 ± 5%; p = 0.08). In both studies, CTMH significantly suppressed the increase of 8-iso-prostaglandin F2αwhile preserving the coronary flow reserve.ConclusionsCatheter-based transcoronary myocardial hypothermia reduced myocardial necrosis while preserving coronary flow reserve, due, in part, to attenuation of oxidative stress.

Recently, late drug-eluting stent (DES) failure has become a potential cause for concern following first-generation DES implantation. Although these phenomena may result from multiple etiologic factors, emerging evidence consistently suggests the importance of delayed arterial healing and

Background Recent pathological studies have demonstrated that peri-strut low intensity area (PLIA) seen on optical coherence tomography (OCT) imaging represents the presence of fibrinogen and/or extracellular matrix. We sought to assess the clinical prevalence of PLIA and its relation to neointimal proliferation after the implantation of sirolimus- (SES) and paclitaxel-eluting stents (PES) in humans. Methods Seventy patients underwent 6-months follow-up OCT after SES (43 stents) or PES (37 stents) implantation. PLIA was defined as a region around stent struts with homogenous lower intensity than surrounding tissue on OCT images without signal attenuation. The incidence of stent struts with PLIA (+PLIA struts) was calculated as the number of +PLIA struts/number of all struts (%). Results PES showed a higher incidence of stents with PLIA than SES (86% vs. 58%; p =0.005) with a higher prevalence of +PLIA struts (27.8±21.9% vs. 10.9±11.0%; p =0.0008). SES with PLIA showed a significantly greater neointimal thickness (NIT) than SES without PLIA ( p =0.02), while PES showed a similar tendency ( p =0.19). In a detailed strut basis analysis, average NIT on +PLIA struts were significantly greater than that on −PLIA struts in both SES and PES. In addition, average NIT was positively correlated with the prevalence of +PLIA struts (SES: Rho=0.73; p p =0.0005) in both stents. Conclusions The prevalence of PLIA was significantly higher in PES than in SES. The presence and extent of PLIA might be associated with intimal thickening after 1st-generation DES implantation.

Background Glucose fluctuation has been recognized as a residual risk apart from dyslipidemia for the development of coronary artery disease (CAD). This study aimed to investigate the association between glucose fluctuation and coronary plaque morphology in CAD patients. Methods This prospective study enrolled 72 consecutive CAD patients receiving adequate lipid-lowering therapy. They were divided into 3 tertiles according to the mean amplitude of glycemic excursions (MAGE), which represents glucose fluctuation, measured by continuous glucose monitoring (tertile 1; 85.3). Morphological feature of plaques were evaluated by optical coherence tomography. Lipid index (LI) (mean lipid arc × length), fibrous cap thickness (FCT), and the prevalence of thin-cap fibroatheroma (TCFA) were assessed in both culprit and non-culprit lesions. Results In total, 166 lesions were evaluated. LI was stepwisely increased according to the tertile of MAGE (1958 ± 974 [tertile 1] vs. 2653 ± 1400 [tertile 2] vs. 4362 ± 1858 [tertile 3], p

The aim of this study is to clarify the morphological characteristics of lesions prone to micro–vascular dysfunction after PCI. A total of 59 culprit lesions from 56 patients with stable angina were examined by OCT before PCI to assess the vulnerable findings of the plaque. Subsequently, the

Background: Nobori is a 3rd generation Drug Eluting Stent (DES), designed to include drug eluting biodegradable polymer coated only abluminal side of the stent. The new features may differently impact inflammation and endothelium functions as compared to the currently marketed DES. At the present time, preclinical data on direct comparison of these DESs are not available. In this study, we examined vascular inflammation and endothelial function of the segments adjacent to the stent and histology of stented areas of Nobori and Cypher DES.

homozygote, A heterozygote and no insertion genotype on case group and control group were 7.5%, 81.1%, and 11.3% and 0%, 98.0%, and 2.0% respectively, and the difference between these two groups were of statistical significance (&chi = 7.88, P = 0.019). (2) There were no statistically significant differences in genotypewithin steroid resistant NS group and non-steroid resistant NS group and hypertension group and non-hypertension group (P N 0.05). Conclusions: There is an adenine insertion in locus rs10305936. The endothelin-A receptor gene polymorphisms in locus rs10305936 are related to the morbidity of nephrotic syndrome in children.

Several investigations revealed that daily glucose fluctuation has adverse effects on endothelial cells. Moreover, we reported that it may have an independent contributing factor on coronary plaque vulnerability. Little is known, however, about its impact on neointimal growth after stenting in

Kunihiro Shimamura 1 , Takashi Akasaka 1 , Keiichi Igarashi 2 , Yasushi Ino 1 , Kazushige Kadota 3 , Masaki Kawamura 4 , Kazuo Kimura 5 , Takeshi Kimura 6 , Ken Kozuma 7 , Takashi Kubo 8 , Akiyoshi Miyazawa 9 , Yoshihiro Morino 10 , Yuji Sakanoue, Toshiro Shinke, Shinjo Sonoda, Tetsuya Sumiyoshi, Kengo Tanabe 1 Wakayama Medical University, Wakayama, Japan, 2 Hokkaido Social Insurance Hospital, Sapporo, Japan, 3 Kurashiki Central Hospital, Kurashiki, Japan, 4 Yokkaichi Social Insurance Hospital, Yokkaichi , Japan, 5 Yokohama City University Medical Center, Yokohama, Japan, 6 Kyoto University, Kyoto, Japan, 7 Teikyo University Hospital, Tokyo, Outside US, Wakayama Medical University, Wakayama, Wakayama, Iwatsuki Minami Hospital, Saitama, Japan, iwate medical university, morioka, Japan, 11 Higashisumiyoshi Morimoto Hospital, OSAKA, Japan, 12 Kobe University Graduate School of Medicine, Kobe-city, Hyogo, 13 University of Occupational and Environmental Health, Kitakyushu, Japan, 14 Sakakibara Heart Institute, Tokyo, Japan, 15 Mitsui Memorial Hospital, Tokyo, Japan

There is a theoretical concern about reduced efficacy of limus-drug for the treatment of diabetics. From the Kobe University OCT data base, 72 lesions (DM: n=27, non-DM: n=45) in 55 patients treated with everolimus-eluting stent (EES) that underwent 8-month follow-up OCT were enrolled. In addition