Effect of intracoronary thrombectomy on 30-day mortality in non-diabetic patients with acute hyperglycemia after acute myocardial infarction

SummaryBackgroundThere is limited evidence about useful therapeutic interventions for patients with acute hyperglycemia (AH) after acute myocardial infarction (AMI).MethodsWe studied 2433 consecutive non-diabetic AMI patients who underwent percutaneous coronary intervention (PCI) within 24h after the onset. Patients were divided into two groups according to the presence or absence of AH (admission serum glucose level ≥11.1mmol/l). We assessed the association between intracoronary thrombectomy and the clinical outcome in AMI patients with AH.ResultsPatients with AH had more risk factors than those without AH. The 30-day mortality rate of patients with AH was significantly higher than that of those without (11.7% vs 1.7%, p<0.001). Among patients with AH, the 30-day mortality rate was significantly lower for those with intracoronary thrombectomy than those without it (4.9% vs 17.2%, p=0.004). Among patients without AH, however, the 30-day mortality rate was similar between those with and without intracoronary thrombectomy (1.5% vs 1.9%, p=NS). Multivariate analysis showed that intracoronary thrombectomy was associated with an improved 30-day mortality rate for patients with AH (hazard ratio: HR 0.184, 95% CI 0.057–0.598, p=0.005).ConclusionsIn AMI patients with AH, intracoronary thrombectomy prior to PCI might improve the 30-day mortality rate

Clinical impact of acute hyperglycemia on development of diabetes mellitus in non-diabetic patients with acute myocardial infarction

AbstractBackgroundAcute hyperglycemia (AH) after the onset of acute myocardial infarction (AMI) is a manifestation of transient abnormal glucose metabolism that may reflect AMI severity, and thus be a predictor of poor prognosis. However, it remains unknown whether AH may predict development of de novo diabetes mellitus (dn-DM) in non-diabetic AMI patients.Methods and resultsAmong AMI patients registered in the Osaka Acute Coronary Insufficiency Study between 1998 and 2007, we investigated hospital records of 1493 patients who had an admission glycated hemoglobin A1c (HbA1c) level of ≤6.0% and were subjected to glycometabolic profiling after survival discharge. dn-DM was defined as initiation of diabetic medication or documentation of an HbA1c level of ≥6.5% during the 5-year follow-up period. AH, defined as an admission serum glucose level of ≥200mg/dl, was observed in 133 (8.9%) patients. dn-DM development was more frequent in post-AMI patients with AH than those without [24.8% vs 12.0%, adjusted hazard ratio (HR) 1.776, p=0.021], particularly among patients with an HbA1c of <5.6% on admission. Treatment with angiotensin-converting enzyme inhibitors or angiotensin receptor blockers was associated with a reduced incidence of dn-DM in patients with AH (adjusted HR 0.397, p=0.031).ConclusionAdmission AH was a predictor of dn-DM in non-diabetic post-AMI patients. Renin–angiotensin system inhibitors were associated with reduced incidence of dn-DM in post-AMI patients with AH

Reduced risk of recurrent myocardial infarction in homozygous carriers of the chromosome 9p21 rs1333049 c risk allele in the contemporary percutaneous coronary intervention era: A prospective observational study

Hara M, Sakata Y, Nakatani D on behalf of the OACIS Investigators, et al. Reduced risk of recurrent myocardial infarction in homozygous carriers of the chromosome 9p21 rs1333049 C risk allele in the contemporary percutaneous coronary intervention era: a prospective observational study. BMJ Open 2014;4:e005438. doi: 10.1136/bmjopen-2014-00543

Impact of hemodialysis on local vessel healing and thrombus formation after drug-eluting stent implantation

AbstractBackgroundAlthough hemodialysis (HD) is a suggested risk factor for stent thrombosis, its contribution to local vessel healing after drug-eluting stent (DES) implantation is unclear.MethodsA total of 121 patients (152 lesions treated with DES) who underwent 8-month follow-up coronary angiography with optical coherence tomography (OCT) were enrolled, and the findings were compared between patients with and without HD. To match baseline differences, mid-term OCT findings of 42 propensity score-matched lesions (21 non-HD vs. 21 HD) were compared. Effects of HD on the efficacy of antiplatelet therapy were also evaluated by VerifyNow assay (Accumetrics, San Diego, CA, USA).ResultsPatients with HD had a significantly higher rate of thrombus formation than those without (64% vs. 33%, p=0.007), although the baseline parameters and lesion characteristics differed between the groups. Multivariate logistic regression analysis revealed that HD was associated with an increased risk of thrombus formation (odds ratio 5.991, 95% confidence interval: 1.972–18.199, p=0.002). Even after propensity-matching for patient background and balancing of angiographic and OCT variables, the risk of thrombus formation remained significantly higher in HD patients. The P2Y12-reaction unit was significantly increased after HD (Pre HD: 211±75 vs. Post HD: 262±59, p=0.01), but patients without HD showed no increase during the same elapsed time (221±88 vs. 212±96, p=0.19).ConclusionsHD is a potential risk factor for subclinical thrombus attachment after DES therapy. Systemic problems, such as residual platelet reactivity, associated with HD as well as local vessel features in HD patients might contribute to the increased incidence of thrombus attachment and subsequent onset of thrombotic event after DES implantation

Association of lifestyle-related factors with circadian onset patterns of acute myocardial infarction: A prospective observational study in Japan

Objective: The onset of acute myocardial infarction (AMI) shows characteristic circadian variations involving a definite morning peak and a less-defined night-time peak. However, the factors influencing the circadian patterns of AMI onset and their influence on morning and night-time peaks have not been fully elucidated. Design, setting and participants: An analysis of patients registered between 1998 and 2008 in the Osaka Acute Coronary Insufficiency Study, which is a prospective, multicentre observational study of patients with AMI in the Osaka region of Japan. The present study included 7755 consecutive patients with a known time of AMI onset. Main outcomes and measures: A mixture of two von Mises distributions was used to examine whether a circadian pattern of AMI had uniform, unimodal or bimodal distribution, and the likelihood ratio test was then used to select the best circadian pattern among them. The hierarchical likelihood ratio test was used to identify factors affecting the circadian patterns of AMI onset. The Kaplan-Meier method was used to estimate survival curves of 1-year mortality according to AMI onset time. Results: The overall population had a bimodal circadian pattern of AMI onset characterised by a high and sharp morning peak and a lower and less-defined night-time peak (bimodal p<0.001). Although several lifestyle-related factors had a statistically significant association with the circadian patterns of AMI onset, serum triglyceride levels had the most prominent association with the circadian patterns of AMI onset. Patients with triglyceride ?150 mg/dL on admission had only one morning peak in the circadian pattern of AMI onset during weekdays, with no peaks detected on weekends, whereas all other subgroups had two peaks throughout the week. Conclusions: The circadian pattern of AMI onset was characterised by bimodality. Notably, several lifestyle-related factors, particularly serum triglyceride levels, had a strong relation with the circadian pattern of AMI onset.Edahiro R, Sakata Y, Nakatani D, et al. Association of lifestyle-related factors with circadian onset patterns of acute myocardial infarction: a prospective observational study in Japan. BMJ Open 2014;4:e005067. doi: 10.1136/bmjopen-2014-00506

Application of Momentum Exchange Impact Dampers to Forging Machine

This paper proposes an impact control method for a forging machine using a momentum exchange impact damper. This method is based on momentum conservation of two colliding bodies. A conventional added mass control method fails to suppress the acceleration and force transmission simultaneously. By using the momentum exchange impact damper, it is shown that the bed acceleration and the transmitted force to the floor are reduced. This paper presents a theoretical analysis of an impact damper and an optimum condition that leads to a minimization of the energy of a forging machine. An experimental analysis is shown to validate the simulation results