Jingxin Zhou

Comparison of Graft Patency Between Off-Pump and On-Pump Coronary Artery Bypass Grafting: An Updated Meta-Analysis

BACKGROUND Currently, off-pump coronary artery bypass grafting (OPCAB) and on-pump coronary artery bypass grafting (ONCAB) are 2 well-established therapeutic strategies for patients with coronary artery disease, and debate regarding which strategy provides superior graft patency is ongoing. The current study is a meta-analysis of randomized controlled trials that compared the graft patency between OPCAB and ONCAB. METHODS Data sources were PubMed, the Cochrane Library, Google Scholar, and ISI Web of Knowledge (1966-2013). We identified studies comparing graft patency after the 2 procedures as the primary intervention for patients with multivessel coronary artery disease and conducted a meta-analysis of randomized controlled trials on graft patency. RESULTS A literature search yielded 12 randomized controlled trials, for a total of 3,894 and 4,137 grafts performed during OPCAB and ONCAB procedures, respectively. Meta-analysis of these studies showed an increased risk of occlusion of all grafts (risk ratio [RR], 1.35; 95% confidence interval [CI], 1.16-1.57) and saphenous vein grafts (SVGs) (RR, 1.41; 95% CI, 1.24-1.60) in the OPCAB group, whereas there was no significant difference in graft occlusion of left internal mammary artery (LIMA) (RR, 1.15; 95% CI, 0.83-1.59) and radial artery (RR, 1.37; 95% CI, 0.76-2.47) grafts between OPCAB and ONCAB. CONCLUSIONS Meta-analysis of currently available randomized controlled trials on graft patency shows that ONCAB reduces the incidence of SVG graft occlusion significantly but does not affect LIMA and radial artery graft patency compared with OPCAB.

The effect of Heparin-VEGF multilayer on the biocompatibility of decellularized aortic valve with platelet and endothelial progenitor cells.

The application of polyelectrolyte multilayer films is a new, versatile approach to surface modification of decellularized tissue, which has the potential to greatly enhance the functionality of engineered tissue constructs derived from decellularized organs. In the present study, we test the hypothesis that Heparin- vascular endothelial growth factor (VEGF) multilayer film can not only act as an antithrombotic coating reagent, but also induce proliferation of endothelial progenitor cells (EPCs) on the decellularized aortic heart valve. SEM demonstrated the adhesion and geometric deformation of platelets. The quantitative assay of platelet activation was determined by measuring the production of soluble P-selectin. Binding and subsequent release of heparin and VEGF from valve leaflets were assessed qualitatively by laser confocal scanning microscopy and quantitatively by ELISA methods. Human blood derived EPCs were cultured and the adhesion and growth of EPCs on the surface modified valvular scaffolds were assessed. The results showed that Heparin-VEGF multilayer film improved decellularized valve haemocompatibility with respect to a substantial reduction of platelet adhesion. Release of VEGF from the decellularized heart valve leaflets at physiological conditions was sustained over 5 days. In vitro biological tests demonstrated that EPCs achieved better adhesion, proliferation and migration on the coatings with Heparin-VEGF multilayer film. Combined, these results indicate that Heparin-VEGF multilayer film could be used to cover the decellularized porcine aortic valve to decrease platelet adhesion while exhibiting excellent EPCs biocompatibility.

MicroRNA-92a Inhibition Attenuates Hypoxia/Reoxygenation-Induced Myocardiocyte Apoptosis by Targeting Smad7

Background MicroRNAs (miRNAs) regulate a lot of physiological and pathological processes, including myocardial ischemia/reperfusion. Recent studies reported that knockdown of miR-92a could attenuate ischemia/reperfusion-induced myocardial injury. In the present study, we examined the potential anti-apoptotic effects of miR-92a in a rat myocardiocyte cell line, and the possible role of Smad7 in such actions. Methodology and Results In a preliminary bioinformatic analysis, we identified SMAD family member 7 (Smad7) as a potential target for miR-92a. A luciferase reporter assay indeed demonstrated that miR-92a could inhibit Smad7 expression. Myocardial ischemia/reperfusion was simulated in rat H9c2 cells with 24-h hypoxia followed by 12-h reoxygenation. Prior to hypoxia/reoxygenation, cells were transfected by miR-92a inhibitor. In some experiments, cells were co-transfected with siRNA-Smad7. The miR-92a inhibitor dramatically reduced the release of lactate dehydrogenase and malonaldehyde, and attenuated cardiomyocyte apoptosis. The miR-92a inhibitor increased SMAD7 protein level and decreased nuclear NF-κB p65 protein. Effects of the miR-92a inhibitor were attenuated by co-transfection with siRNA-Smad7. Conclusion Inhibiting miR-92a can attenuate myocardiocyte apoptosis induced by hypoxia/reoxygenation by targeting Smad7.

Closure of patent foramen ovale and prevention of recurrent thromboembolic events

We read with great interest the article by Pineda et al. [1]. In the study, Pineda et al. conducted a metaanalysis of three randomized controlled trials (RCTs) available on the risk of recurrent thromboembolic events after transcatheter closure of patent foramen ovale (PFO) versus medical therapy alone. Currently, which of the two therapies is better for patients with cryptogenic stroke and concomitant PFO remains undetermined. One prospective, RCT is still insufficient. Therefore, it is important and timely to perform this meta-analysis of RCTs on this theme. To our knowledge, this is the first meta-analysis of RCTs on the risk of recurrent thromboembolic events after transcatheter closure of PFO versus medical therapy alone. In the study, Pineda et al. concluded that successful transcatheter closure of PFO might be more effective than medical therapy alone for the prevention of recurrent thromboembolic events. However, several intrinsic limitations of this meta-analysis should be noted and the results must be interpreted with caution. First, in the intention-to-treat analysis, composite results of primary end points showed no significant benefit of closure of PFO over medical therapy alone (OR, 0.70, 95%CI 0.47 to 1.05). Then they concluded that closure of PFO showed significant benefit over medical therapy alone (OR, 0.62, 95%CI 0.41 to 0.94) on the as-treated analysis. However, the as-treated analysis appeared biased in patient enrollment. For example, in the RESPECT trial [2], there were 25 patients who were removed from the intention-to-treat closure group. Of them, 4 (16%) had a stroke. This stroke rate is significantly higher than the average stroke rate (1.1%) among patients in the as-treated closure group. They were inclined to have a stroke clearly. Therefore, it might create an as-treated closure group at low risk to remove them from the analysis. Second, in the as-treated analysis, primary end-point events included transient ischemic attack (TIA) and cerebrovascular event (CVA). As we all know, compared with CVA, TIA was a less clear-cut end point, which might result in an increased ischemic event rate and a dilution of effects if it was included as an estimate. In summary, up to date, there is still no enough evidence to indicate that closure of PFO is superior to medical therapy alone for patients with cryptogenic stroke and concomitant PFO. Therefore, further studies should be considered in future association studies to confirm the results from this meta-analysis.

Minimally invasive direct coronary artery bypass reduces the need for repeated revascularization at long-term follow-up compared with stenting: A meta-analysis

The incidence of coronary artery disease involving the left anterior descending artery (LAD) is reportedly as high as 50% among patients undergoing coronary artery bypass grafting, and lesions in the LAD are associated with a significantly worse prognosis than those in other coronary arteries [1]. To date, two approaches have been well established for revascularization in patients with isolated lesions of the LAD: transluminal, as in percutaneous transluminal coronary artery stenting (PTCS), and surgical bypass, as in minimally invasive direct coronary artery bypass (MIDCAB). Previously published meta-analyses [2,3] have reported the midterm results after MIDCAB versus PTCS. New randomized controlled trials and long-term results have been published, indicating the need for a new meta-analysis. Thus, we performed a meta-analysis to compare the long-term clinical outcomes of interest after MIDCAB versus PTCS for the management of isolated lesions of the LAD. To identify all prospective randomized controlled trials ofMIDCAB versus PTCS that enrolled patients with isolated lesions of the LAD, public domain databases including PubMed, the Cochrane Library, Google Scholar, and ISI Web of Knowledge were searched for papers published until June 2013.