Masahiro Myojo

Prognostic implication of macrocytosis on adverse outcomes after coronary intervention

BACKGROUND Macrocytosis, as a qualitative abnormality of erythrocytes, has not drawn attention as a prognostic indicator after PCI, while anemia, as a quantitative abnormality of erythrocytes, has been recognized as a predictor of adverse outcomes. The aim of this study was to perform prognostic risk stratification of patients after PCI based on the presence or absence of macrocytosis. METHODS The clinical records of 941 consecutive patients who underwent PCI at a single institution were retrospectively reviewed. The prognostic implication of macrocytosis was evaluated by univariate and multivariate Coxs proportional hazard regression analysis. RESULTS There were 130 (13.8%) patients with macrocytosis. A significantly higher all-cause and cardiac mortality, as well as incidence of composite adverse events were observed in the Macrocytic group. Kaplan-Meier analysis also showed a significantly poorer overall survival in patients with macrocytosis. Even after exclusion of anemic patients, this tendency was still observed. Furthermore, macrocytosis was significantly and independently associated with adverse outcomes after PCI (aHR of cardiac death: 3.45, 95%CI: 1.22-9.80, P=0.019). Interestingly, fewer patients with macrocytosis were prescribed statins compared with those without it (33.8% vs. 47.1%, P=0.005). CONCLUSIONS The results of the study indicate that measuring mean corpuscular volume (MCV) as a qualitative index of erythrocytes might be helpful for a prognostic risk stratification of patients subjected to PCI.

Involvement of P2Y12 receptor in vascular smooth muscle inflammatory changes via MCP-1 upregulation and monocyte adhesion

Antiplatelet drugs, frequently used for cardiovascular events with thrombotic involvement, are also regarded as possible promising agents for cardiovascular primary prevention. The roles of P2Y12, an ADP receptor and the target of thienopyridine antiplatelet drugs, are not satisfactorily known in the vascular wall. We investigated the hypothesis that vascular smooth muscle cell (VSMC) P2Y12 is involved in vascular wall inflammatory changes by upregulating monocyte chemoattractant protein-1 (MCP-1) and promoting monocyte adhesion. ADP at 10(-5) M induced a 3.6 ± 0.3-fold upregulation of MCP-1 mRNA in cultured rat VSMCs, which was significantly inhibited by R-138727, the active metabolite of P2Y12 inhibitor prasugrel and siRNAs against P2Y12. ADP also induced MCP-1 protein upregulation, which was diminished by R-138727 and P2Y12 siRNAs. JNK (c-Jun NH2-terminal kinase) inhibition attenuated ADP-induced MCP-1 mRNA and protein upregulation. R-138727 and P2Y12 siRNAs inhibited ADP-induced JNK activation. The reactive oxygen species (ROS) inhibitors N-acetylcysteine (NAC), diphenyleneiodonium (DPI), and Tempol also diminished MCP-1 upregulation and JNK activation induced by ADP. ADP induced MCP-1 promoter activation, which was inhibited by R-138727 and P2Y12 siRNAs. Nuclear factor-κB (NF-κB) consensus sites in the MCP-1 promoter region were involved in this activation. ADP-induced NF-κB pathway activation, examined by a plasmid containing multiple NF-κB sites, was diminished by P2Y12 inhibition. For cellular function analysis, stimulation of VSMC with ADP increased subsequent THP-1 monocyte adhesion. P2Y12 siRNAs and CCR2 antagonism diminished this ADP-induced monocyte adhesion. These data suggested that ADP, via the VSMC P2Y12 receptor, induces vascular inflammatory changes by upregulating MCP-1 and promoting monocyte adhesion.

Aldosterone-induced osteopontin gene transcription in vascular smooth muscle cells involves glucocorticoid response element

Osteopontin (OPN) is known to be one of the cytokines that is involved in the vascular inflammation caused by aldosterone (Aldo). Previous reports have shown that Aldo increases OPN transcripts, and the mechanisms for this remain to be clarified. In this study, we investigated how Aldo increases OPN transcripts in the vascular smooth muscle cells of rats. Aldosterone increased OPN transcripts time-dependently as well as dose-dependently. This increase was diminished by eplerenone, a mineralocorticoid receptor (MR) antagonist. Luciferase promoter assays showed that the OPN promoter deleted to the −1599 site retained the same promoting ability as the full-length OPN promoter when stimulated by 10−7 M Aldo, but the promoter deleted to the −1300 site lost the promoting ability. A glucocorticoid response element (GRE) is located in that deleted region. Luciferase assays of a mutated promoter without the GRE lost the luciferase upregulation, although mutated promoters with the deletion of other consensus sites maintained the promoter activity. The binding of the Aldo–MR complex to the GRE fragment was confirmed by an electrophoretic-mobility shift assay. This is the first report showing that Aldo regulates the transcriptional levels of OPN and inflammatory responses in the vasculature through a specific GRE site in the OPN promoter region.

Plasma neutrophil gelatinase-associated lipocalin predicts major adverse cardiovascular events after cardiac care unit discharge

BACKGROUND Emerging acute kidney injury biomarkers, including neutrophil gelatinase-associated lipocalin (NGAL), have a high potential for predicting worsening renal function. Acute exacerbation of renal dysfunction has a great impact on the outcomes of cardiovascular patients in critical conditions. This study aimed to evaluate whether plasma NGAL can predict the mortality and major adverse cardiovascular events (MACEs) after discharge from the cardiac care unit (CCU). METHODS Patients who were admitted to the CCU of the Tokyo University Hospital were prospectively enrolled (101 patients). Blood and urinary markers, including the blood NGAL, brain natriuretic peptide, creatinine, cystatin C, urinary albumin, N-acetyl-β-d-glucosaminidase, and L-type fatty acid-binding protein, were measured at CCU discharge. The primary outcome was MACEs until at least 6 months after CCU discharge. RESULTS Thirty-five patients experienced MACEs (35%). Multivariate logistic analysis revealed that the plasma NGAL, length of CCU stay, and existence of diabetes and heart failure were independent predicting factors for MACEs. Patients with the highest NGAL at discharge (>75th percentile) showed a significantly higher risk of MACEs than those with the lowest NGAL (<25th percentile) (log-rank test; hazard ratio, 5.15; 95% confidence interval 1.84-18.20; p<0.01). CONCLUSION Plasma NGAL at CCU discharge is a significant prognostic indicator of outcomes at 6 months in critically ill cardiac patients treated in a CCU.

Impact of the Distance from the Stent Edge to the Residual Plaque on Edge Restenosis following Everolimus-Eluting Stent Implantation

Objectives This study aimed to assess the relation between stent edge restenosis (SER) and the distance from the stent edge to the residual plaque using quantitative intravascular ultrasound. Background Although percutaneous coronary intervention with drug-eluting stents has improved SER rates, determining an appropriate stent edge landing zone can be challenging in cases of diffuse plaque lesions. It is known that edge vascular response can occur within 2 mm from the edge of a bare metal stent, but the distance to the adjacent plaque has not been evaluated for drug-eluting stents. Methods A total of 97 proximal residual plaque lesions (plaque burden [PB] >40%) treated with everolimus-eluting stents were retrospectively evaluated to determine the distance from the stent edge to the residual plaque. Results The SER group had significantly higher PB (59.1 ± 6.1% vs. 51.9 ± 9.1% for non-SER; P = 0.04). Higher PB was associated with SER, with the cutoff value of 54.74% determined using receiver operating characteristic (ROC) curve analysis. At this cutoff value of PB, the distance from the stent edge to the lesion was significantly associated with SER (odds ratio = 2.05, P = 0.035). The corresponding area under the ROC curve was 0.725, and the cutoff distance value for predicting SER was 1.0 mm. Conclusion An interval less than 1 mm from the proximal stent edge to the nearest point with the determined PB cutoff value of 54.74% was significantly associated with SER in patients with residual plaque lesions.

Telmisartan Activates Endothelial Nitric Oxide Synthase via Ser1177 Phosphorylation in Vascular Endothelial Cells

Because endothelial nitric oxide synthase (eNOS) has anti-inflammatory and anti-arteriosclerotic functions, it has been recognized as one of the key molecules essential for the homeostatic control of blood vessels other than relaxation of vascular tone. Here, we examined whether telmisartan modulates eNOS function through its pleiotropic effect. Administration of telmisartan to mice significantly increased the phosphorylation level of eNOS (Ser1177) in the aortic endothelium, but administration of valsartan had no effect. Similarly, telmisartan treatment of human umbilical vein endothelial cells significantly increased the phosphorylation levels of AMP-activated protein kinase (Thr172) and eNOS and the concentration of intracellular guanosine 3′,5′-cyclic monophosphate (cGMP). Furthermore, pretreatment with a p38 mitogen-activated protein kinase (p38 MAPK) inhibitor suppressed the increased phosphorylation level of eNOS and intracellular cGMP concentration. These data show that telmisartan increases eNOS activity through Ser1177 phosphorylation in vascular endothelial cells mainly via p38 MAPK signaling.

Is it possible to perform gastric endoscopic submucosal dissection without discontinuation of a single antiplatelet of thienopyridine derivatives

Background and study aims  Combined use of thienopyridine derivatives and other antithrombotic agents is reported to be a risk factor for postoperative bleeding after gastric endoscopic submucosal dissection (ESD). However, risk associated with a single thienopyridine derivative has not been evaluated. In this study, we aimed to evaluate bleeding risks of gastric ESD without discontinuation of a single thienopyridine derivative agent. Patients and methods  This multicenter, prospective, observational cohort study included patients who had undergone implantation of a coronary artery stent and who were taking a combination of aspirin antiplatelet therapy and a thienopyridine derivative agent. Enrolled patients discontinued aspirin and underwent gastric ESD without the discontinuation of a single thienopyridine derivative agent. The primary endpoint was the major bleeding complication rate after gastric ESD. Results  Eleven patients were enrolled in this study from April 2015 to November 2016 after written informed consent was obtained. Among them, 1 patient, who had undergone surgery for a primary cardiac tumor before ESD, was excluded from the study. Ten patients underwent gastric ESD for neoplasms. En-bloc resections were achieved in all cases without intraoperative bleeding complications. Two patients experienced postoperative bleeding although neither case required a blood transfusion (95 % CI 2.5 – 55.6 %). Conclusion  En-bloc resections were possible although the postoperative bleeding rate tended to be higher in gastric ESD without discontinuation of a single thienopyridine derivative agent. Additional preventive measures are mandatory to carry out safe gastric ESD in such settings.

Coronary Artery Aneurysm Caused by a Stent Fracture: A Case Report and Management Overview

Coronary stent fracture (SF) is rare as a complication of percutaneous coronary intervention (PCI), and its adverse events are increasingly being recognized with the development in devices of PCI. The major adverse events caused by SFs are in-stent restenosis due to neointimal overgrowth caused by poor drug delivery.1,2) A coronary artery aneurysm (CAA) is a rare complication of SF, but may lead to lethal events such as acute coronary syndrome or rupture of the CAA further leading to cardiac tamponade.3-5) However, the management of CAAs is controversial with or without SF.6) Herein, we report a case of a CAA caused by an SF and discuss the management of CAA complicated with SF, along with a literature review. We suggest that surgical treatment should be considered the higher-priority strategy in the cases of CAA with SF as compared to CAA without SF.

Midterm Follow‐up After Retrievable Inferior Vena Cava Filter Placement in Venous Thromboembolism Patients With or Without Malignancy

A clear indication and strategy for placement of retrievable inferior vena cava filters (IVCFs) have not been established. This study was designed to evaluate the efficacy and disadvantages of the retrievable IVCF use particularly in venous thromboembolism (VTE) patients with malignancy.