Interview With Marc Ruel: Thoughts on Minimally Invasive Cardiac Surgery and the MIST Trial

<p>Om Prakesh Yadava, of the National Heart Institute in New Delhi, India, interviews Marc Ruel of the University of Ottawa in Canada. Drs Yadava and Ruel discuss minimally invasive cardiac surgery (MICS), its benefit in both the developing and developed world, and the MIST (minimally invasive versus sternotomy) trial.<br></p><p>Dr Marc Ruel feels that cardiac surgery, being a reconstructive and not an ablative specialty, was slow in developing MICS but that it is now on track as even developing countries like India have taken to it with gusto. He encourages collaboration between the developing and developed world. Taking a cue from a recent editorial by Kappetein and Vahanian [1], Dr Ruel discusses the terms, "efficacy" and "effectiveness," where efficacy refers to controlled conditions and effectiveness refers to real life and unmonitored situations. He comments that although MICS is definitely efficacious, effectiveness has yet to be proven. He stresses that specialized centers should be developed and that these procedures should be done, at least at this stage, in those specialized centers.</p><p>Dr Yadava asks whether these technologies are relevant to a developing country such as India, given that science must answer to the aspirations of the society and considering the different contexts of cost containment in the western world and India. Dr Ruel responded that these surgeries are all the more important to a developing country like India, as the medical and social networks are not as strong as in other countries and therefore, patients need to get back to work faster. This is one major advantage of MICS: shorter convalescence and early return to gainful employment. Dr Ruel feels that MICS helps society and is therefore relevant to the developing world. Mechanical circulatory support devices and transplantation impact an individual or a family and might even help in the branding of an institution, but they do not produce great benefits to the society at large. Minimally invasive techniques, however, are very relevant to the community and society, especially in the field of coronary artery disease, which is rampant in Southeast Asia.</p><p>Dr Ruel then discusses the rationale, inclusion and exclusion criteria, and the primary and secondary end points of the MIST trial. He also discusses the methodology being adopted for the trial, which compares the minimally invasive approach with sternotomy for coronary artery disease. Dr Ruel is the principal investigator of this multicenter international randomized controlled trial. He states that though there is some level of observational data, there is no randomized controlled trial comparing these two approaches to surgically treating coronary artery disease. The MIST trial aims to bridge that gap.</p><hr><p>Reference</p><ol><li>Kappetein AP, Vahanian A. Effectiveness in a real-world observation confirms efficacy of controlled clinical trials. <a href="https://doi.org/10.1016/j.jacc.2017.06.013"><em>J Am Coll Cardiol</em>. 2017;70(4):451-452</a>.</li></ol

Additional file 1: Figure S1. of The impact of patient co-morbidities on the regenerative capacity of cardiac explant-derived stem cells

Histogram of LTS frequency distribution in patient samples used to culture EDCs for experimentation. Figure S2. Effect of patient LTS score on cytokine production. Correlation between LTS score and cytokine content within EDC conditioned media (FGF, fibroblast growth factor, n = 16; HGF, heptocyte growth factor, n = 16; PDGF, platelet derived growth factor, n = 15 EDC cell lines; SCF, stem cell factor, n = 16 EDC cell lines; TNF, tumor necrosis factor, n = 16 EDC cell lines; VEGF, vascular endothelial growth factor, n = 13 EDC cell lines). Table S1. Comparison of outcomes assessed in different quantitative measures of health scoring systems. (DOCX 339 kb

Additional file 1: of Should dual antiplatelet therapy be used in patients following coronary artery bypass surgery? A meta-analysis of randomized controlled trials

Description of Excluded RCTs. (DOC 63 kb

Collagen-Based Photoactive Agent for Tissue Bonding

Using a combination of methacrylated collagen and the photosensitizer rose Bengal, a new light-activated biomimetic material for tissue sutureless bonding was developed. This formulation was cross-linked using green light. In vivo tests in mice demonstrate the suitability of the material for sutureless wound closure

A novel echocardiographic hemodynamic index for predicting outcome of aortic stenosis patients following transcatheter aortic valve replacement

<div><p>Objective</p><p>Transcatheter aortic valve replacement (TAVR) reduces left ventricular (LV) afterload and improves prognosis in aortic stenosis (AS) patients. However, LV afterload consists of both valvular and arterial loads, and the benefits of TAVR may be attenuated if the arterial load dominates. We proposed a new hemodynamic index, the Relative Valve Load (RVL), a ratio of mean gradient (MG) and valvuloarterial impedance (Zva), to describe the relative contribution of the valvular load to the global LV load, and examined whether RVL predicted patient outcome following TAVR.</p><p>Methods</p><p>A total of 258 patients with symptomatic severe AS (indexed aortic valve area (AVA)<0.6cm²/m², AR≤2+) underwent successful TAVR at the University of Ottawa Heart Institute and had clinical follow-up to 1-year post-TAVR. Pre-TAVR MG, AVA, percent stroke work loss (%SWL), Zva and RVL were measured by echocardiography. The primary endpoint was all cause mortality at 1-year post TAVR.</p><p>Results</p><p>There were 53 deaths (20.5%) at 1-year. RVL≤7.95ml/m² had a sensitivity of 60.4% and specificity of 75.1% for identifying all cause mortality at 1-year post-TAVR and provided better specificity than MG<40 mmHg, AVA>0.75cm², %SWL≤25% and Zva>5mmHg/ml/m² despite equivalent or better sensitivity. In multivariable Cox analysis, RVL≤7.95ml/m² was an independent predictor of all cause mortality (HR 3.2, CI 1.8–5.9; p<0.0001). RVL≤7.95ml/m² was predictive of all cause mortality in both low flow and normal flow severe AS.</p><p>Conclusions</p><p>RVL is a strong predictor of all-cause mortality in severe AS patients undergoing TAVR. A pre-procedural RVL≤7.95ml/m² identifies AS patients at increased risk of death despite TAVR and may assist with decision making on the benefits of TAVR.</p></div

Study protocol of inclusion and exclusion criteria.

<p>SAVR = surgical aortic valve replacement, TAVR = transcatheter aortic valve replacement.</p

Receiver operator curve analysis of the hemodynamic indices for predicting the combined outcome of all cause mortality or cardiovascular re-admission 1-year post-TAVR.

<p>Receiver operator curve analysis of the hemodynamic indices for predicting the combined outcome of all cause mortality or cardiovascular re-admission 1-year post-TAVR.</p

Comparison of the sensitivity and specificity of hemodynamic indices for predicting the combined outcome of all cause mortality or cardiovascular re-admission 1-year post-TAVR.

<p>Comparison of the sensitivity and specificity of hemodynamic indices for predicting the combined outcome of all cause mortality or cardiovascular re-admission 1-year post-TAVR.</p

Kaplan-Meier survival curves post-TAVR based on RVL and SVI.

<p>RVL = Relative Valve Load, SVI = stroke volume index.</p

Comparison of the sensitivity and specificity of hemodynamic indices for predicting all cause mortality 1-year post-TAVR.

<p>Comparison of the sensitivity and specificity of hemodynamic indices for predicting all cause mortality 1-year post-TAVR.</p