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AimsMyocardial strain analysis enables more precise assessment of cardiac performance but is relatively load dependent. New tools have been developed with afterload adjustment. Our objective was to assess myocardial work (MW) in patients with repaired aortic coarctation (rACo).MethodsProspective study of consecutive patients with rACo who underwent a routine transthoracic echocardiogram in 2018 and 2019 at our center. Patients with significant aortic valve disease, pacemaker, or other congenital heart diseases (except for mild bicuspid aortic valve disease) were excluded. Global longitudinal strain with two dimensional speckle tracking analysis and MW were obtained (GWI:Global Work Index; GCW: Global Constructive Work; GWW: Global Wasted Work; GWE: Global Work Efficiency). Blood pressure was measured in the patient's right arm.ResultsWe included 42 patients in the analysis, mean age of 37±10 years, 38% males. In this group, 52% had hypertension and 64% had a concomitant bicuspid aortic valve. In comparison to previously published reference values, patients with rACo had significantly lower GWI (1807 vs. 1896 mmHg%) and GCW (2173 vs. 2232 mmHg%) (p<0.001), particularly in males. Systolic blood pressure is an independent predictor for GWI (β=0.432) and for GCW (β=0.534) and GLS an independent predictor of all MW parameters (β>0.594). Neither age nor gender were independent predictors.ConclusionsIn patients with rACo, there are some signs of left ventricular dysfunction with a reduction in GCW and GWI and with preserved GWE, despite normal ejection fraction and strain.  相似文献   
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Coronary embolism (CE) is an uncommon and unique cause of acute myocardial infarction. In this report, we review 216 cases of CE including 2 new cases from our institution. The mean patient age was 52.5 years and 62% of the patients were males. Chest pain was the most common presenting symptom followed by dyspnea, and the most commonly affected vessel was the left anterior descending artery. Leading etiologies of the embolus were atrial fibrillation, septic emboli, and iatrogenic causes. Treatment approaches varied with thrombus aspiration being used in 30% of cases. In-hospital mortality rate was 36% and 13% of the cases were complicated by cerebrovascular accident. CE is a unique pathology that leads to acute myocardial infarction. It portends a high mortality rate and requires a high level of suspicion as symptoms may be misleading. Further research is needed in order to improve recognition and management and to lower associated mortality.  相似文献   
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PurposeTo examine the long-term clinical outcomes of patients with anti-centromere antibody (ACA)-positive critical limb-threatening ischemia (CLTI) who were treated with endovascular therapy (EVT).Materials and MethodsThis was a retrospective analysis using a database of 423 consecutive CLTI patients (543 limbs, Rutherford class 4–6) who underwent EVT between January 2011 and March 2013. The patients were divided into 2 groups: an ACA-positive group (10 limbs, 8 patients) and a control group (46 limbs, 43 patients). The control group was defined as female, non-dialysis, and those who were able to obtain a below-knee angiogram.ResultsNone of the 8 ACA-positive CLTI patients had previously been diagnosed as ACA positive. No significant difference was observed in the below-the-knee lesion distribution and severity between the ACA-positive group and the control group. The median observational period was 51 months. The survival rate was 54% in the ACA-positive group and 76% in the control group at 5 years after EVT (P = .732). The freedom from major amputation rate was 60% in the ACA-positive group and 91% in the control group at 5 years after EVT (P = .029). The technical EVT success rate in the ACA-positive group was 70% (7/10). Of the successful EVT cases, 71% (5/7) of patients achieved complete wound healing or rest pain relief; however, 60% (3/5) had a recurrence of wounds.ConclusionsIn a series of ACA-positive patients with CLTI, successful EVT had acceptable outcomes with respect to wound healing with short-term results. However, the major amputation rate for ACA-positive patients was high in long-term follow-up.  相似文献   
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Shouwen Zhang  Jie Wang 《Drug delivery》2016,23(9):3696-3703
Context: Baicalin has many pharmacological activities, including protective function against myocardial ischemia by antioxidant effects and free radical scavenging activity. However, its rapid elimination half-life in plasma and poor water solubility limits its clinical efficacy.

Objective: Novel baicalin-loaded PEGylated nanostructured lipid carriers (BN-PEG-NLC) were developed to improve bioavailability of BN, to prolong retention time in vivo and to enhance its protective effect.

Methods: In this study, BN-PEG-NLC were prepared by the emulsion-evaporation and low temperature-solidification method using a mixture of glycerol monostearate and polyethylene glycol monostearate as solid lipids, and oleic acid as the liquid lipid. The physicochemical properties of NLC were characterized. The pharmacokinetic and pharmacodynamic behaviors of BN-PEG-NLC or BN-NLC were evaluated in acute MI rats.

Results and discussion: The particle size, zeta potential, and entrapment efficiency for BN-PEG-NLC were observed as 83.9?nm, ?32.1?mV, and 83.5%, respectively. The release profiles of BN from both BN-PEG-NLC and BN-NLC were fitted to the Ritger–Peppas modal, which presented burst release initially and prolonged release afterwards. Pharmacokinetics results indicated that BN-PEG-NLC exhibited a 7.2-fold increase in AUC in comparison to BN solution, while a 3-fold increase in comparison to BN-NLC. Biodistribution results revealed that BN-PEG-NLC exhibited higher heart drug concentration compared with BN-NLC as well as BN solution. In the present study, BN-PEG-NLC significantly ameliorated infarct size.

Conclusion: The results of the present study imply that PEG-NLC could be the biocompatible carriers for heart-targeted drug delivery to improve myocardial ischemia.  相似文献   
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BackgroundIschemia reperfusion (I/R) play an imperative role in the expansion of cardiovascular disease. Sinomenine (SM) has been exhibited to possess antioxidant, anticancer, anti-inflammatory, antiviral and anticarcinogenic properties. The aim of the study was scrutinized the cardioprotective effect of SM against I/R injury in rat.MethodsRat were randomly divided into normal control (NC), I/R control and I/R + SM (5, 10 and 20 mg/kg), respectively. Ventricular arrhythmias, body weight and heart weight were estimated. Antioxidant, inflammatory cytokines, inflammatory mediators and plasmin system indicator were accessed.ResultsPre-treated SM group rats exhibited the reduction in the duration and incidence of ventricular fibrillation, ventricular ectopic beat (VEB) and ventricular tachycardia along with suppression of arrhythmia score during the ischemia (30 and 120 min). SM treated rats significantly (P < 0.001) altered the level of antioxidant parameters. SM treatment significantly (P < 0.001) repressed the level of creatine kinase MB (CK-MB), creatine kinase (CK) and troponin I (Tnl). SM treated rats significantly (P < 0.001) repressed the tissue factor (TF), thromboxane B2 (TXB2), plasminogen activator inhibitor 1 (PAI-1) and plasma fibrinogen (Fbg) and inflammatory cytokines and inflammatory mediators.ConclusionOur result clearly indicated that SM plays anti-arrhythmia effect in I/R injury in the rats via alteration of oxidative stress and inflammatory reaction.  相似文献   
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