When cheating turns into a stabilizing mechanism of plant-pollinator communities.

Mutualistic interactions, such as plant-mycorrhizal or plant-pollinator interactions, are widespread in ecological communities and frequently exploited by cheaters, species that profit from interactions without providing benefits in return. Cheating usually negatively affects the fitness of the individuals that are cheated on, but the effects of cheating at the community level remains poorly understood. Here, we describe 2 different kinds of cheating in mutualistic networks and use a generalized Lotka-Volterra model to show that they have very different consequences for the persistence of the community.

Efficacy of maintaining low-tidal volume mechanical ventilation as compared to resting lung strategy during coronary artery bypass graft cardiopulmonary bypass surgery: A post-hoc analysis of the MECANO trial.

Study Objective: To compare a low-tidal-volume with positive end-expiratory pressure strategy (VENT strategy) to a resting-lung-strategy (i.e., no-ventilation (noV) strategy) during cardiopulmonary bypass for coronary artery bypass graft surgery on the incidence of postoperative pulmonary complications.

Efficacy of parasternal block to decrease intraoperative opioid use in coronary artery bypass surgery via sternotomy: a randomized controlled trial.

Objective: This study aims to assess the effect of a preoperative parasternal plane block (PSB) on opioid consumption required to maintain hemodynamic stability during sternotomy for coronary artery bypass graft surgery.

Methods: This double-blind, randomized, placebo-controlled trial prospectively enrolled 35 patients scheduled for coronary artery bypass graft surgery under general anesthesia with propofol and remifentanil. Patients were randomized to receive preoperative PSB using either ropivacaine (PSB group) or saline solution (placebo group) (1:1 ratio).

Low Tidal Volume Mechanical Ventilation Against No Ventilation During Cardiopulmonary Bypass in Heart Surgery (MECANO): A Randomized Controlled Trial.

Background: Postoperative pulmonary complications are common after cardiac surgery and have been related to lung collapse during cardiopulmonary bypass (CPB). No consensus exists regarding the effects of maintaining mechanical ventilation during CPB to decrease these complications.

Research Question: To determine whether maintaining low-tidal ventilation (3 mL/kg 5 times/min, with positive end expiratory pressure of 5 cm HO) during CPB (ventilation strategy) was superior to a resting-lung strategy with no ventilation (no ventilation strategy) regarding postoperative pulmonary complications, including mortality.

Low tidal volume mechanical ventilation against no ventilation during cardiopulmonary bypass heart surgery (MECANO): study protocol for a randomized controlled trial.

Background: Postoperative pulmonary complications are a leading cause of morbidity and mortality after cardiac surgery. There are no recommendations on mechanical ventilation associated with cardiopulmonary bypass (CPB) during surgery and anesthesiologists perform either no ventilation (noV) at all during CPB or maintain low tidal volume (LTV) ventilation. Indirect evidence points towards better pulmonary outcomes when LTV is performed but no large-scale prospective trial has yet been published in cardiac surgery.

First experimental use of magnets in cardiac valve repair.

Background And Aim Of The Study: Valve repair is currently performed to treat mitral regurgitation, but aortic valve repair remains a surgical challenge. In contrast, aortic valve replacement leads to complications and constraints on the patients' quality of life and valve durability. The mechanisms that produce malcoaptation of the aortic leaflets, with resultant insufficiency, are mainly due to prolapse or retraction of the leaflets.

Is an anterior mitral leaflet prolapse still a challenge?

Quadrangular resection is the gold standard in the treatment of posterior leaflet prolapse. Anterior leaflet prolapse has been considered a more challenging problem; several techniques are available to treat it, all with the same goal - mitral valve competency. Nowadays, good long-term results are reported, similar to those for posterior leaflet prolapse.

Extra-corporeal membrane oxygenation temporary support for early graft failure after cardiac transplantation.

Objective: Early graft failure (EGF) is a major risk for death after heart transplantation. We studied the impact of an extra-corporeal membrane oxygenation (ECMO) temporary support on the operative mortality and the mean-term survival after EGF.

Materials And Methods: Between January 2000 and December 2006, 394 patients underwent orthotopic heart transplantation at our institution.

A simplified surgical approach for aortic valve replacement after previous coronary artery bypass grafting.

Aortic valve replacement (AVR) in patients who have undergone previous coronary artery bypass grafting (CABG) is a challenging redo surgery. We undertook this study to evaluate the early and late outcomes of patients operated upon using a simplified surgical approach. Between January 2001 and December 2005, 2238 patients underwent AVR in our institution.

Gaping cleft or commissure--an under-rated cause of residual mitral insufficiency following valve repair: case reports.

Naturally occurring clefts in the posterior leaflet of the mitral valve and/or the mitral commissures themselves may become the foci of residual mitral regurgitation when distorted by an adjacent rigid suture line. Herein are reported the details of three cases in which cleft/commissure closure resolved such leaks. The anatomical substrate which predisposed to this problem is also discussed.

Revisiting the localisation of Zn(2+) cations sorbed on pathological apatite calcifications made through X-ray absorption spectroscopy.

The role of oligo-elements such as Zn in the genesis of pathological calcifications is widely debated in the literature. An essential element of discussion is given by their localisation either at the surface or within the Ca apatite crystalline network. To determine the localisation, X-ray absorption experiments have been performed at SOLEIL.

Paracorporeal pulsatile biventricular assist device versus extracorporal membrane oxygenation-extracorporal life support in adult fulminant myocarditis.

Objective: Biventricular assist device support with a paracorporeal pulsatile device is known to be an efficient bridge to recovery for patients with fulminant myocarditis-related cardiogenic shock. Whether these patients can be as efficiently supported with femorofemoral extracorporeal membrane oxygenation remains unclear.

Methods: From 2001 to 2006, 11 patients were referred to our cardiac surgery department for fulminant myocarditis-related cardiogenic shock.

Circumflex coronary artery injury following mitral annuloplasty treated by emergency angioplasty.

Iatrogenic injury to the circumflex coronary artery following mitral annuloplasty is a potentially fatal complication. It can be clinically silent or else be responsible for a cardiogenic shock. The diagnosis should be suspected on EKG changes with segmental dysfunction of the lateral wall on the intraoperative echography.

[Cardiac transplantation in 2008].

The number of heart transplants in France has begun to increase again in the past few years, albeit slowly. Indications for transplants must be discussed on a case-by-case basis and no contraindication should be considered absolute. Heart transplant results have not been modified by the expansion of the selection criteria for donors.

A safe option to perform an apparent difficult redo surgery.

A 50-year-old female operated of Bentall five years before was referred to our hospital for an aneurysm of both right subclavian artery and brachiocephalic trunk associated with a false anastomotic aneurysm on the insertion of the left coronary artery. The procedure was performed under moderate hypothermic circulatory arrest; the false aneurysm was repaired, the brachiocephalic trunk and the subclavian aneurysm were resected, an aorto-carotid and axillary bypass were finally performed. The postoperative course was uneventful.

Surgery for infective endocarditis on mitral annulus calcification.

Background And Aim Of The Study: The study aim was to assess the characteristics of bacterial endocarditis complicating mitral annulus calcification, and to evaluate the surgical results.

Methods: Twenty-four patients (mean age 64 years) underwent surgery for mitral insufficiency secondary to mitral endocarditis with annulus calcification (acute, n = 18; healed, n = 6). Surgery was performed as an emergency in seven cases for septic (n = 3) or cardiogenic (n = 4) shock.

Mitral annulus calcification: determinants of repair feasibility, early and late surgical outcome.

Objective: The aim of this study was to determine the factors influencing the feasibility of valve repair and the surgical outcome in patients with mitral annulus calcification.

Methods: In 124 patients with mitral annulus calcification undergoing surgery, two entities were distinguished: Barlow disease (myxomatous leaflets, n=60) and fibroelastic deficiency (FED) (normal leaflets, n=64). The calcification score was lower (1.

Limited mechanical circulatory support following orthotopic heart transplantation.

Shortage of donors enhances harvesting of borderline hearts. When such organs fail, a ventricular assist device may salvage the patient waiting for either recovery or for retransplantation. We describe a series of 12 patients who required circulatory support following orthotopic heart transplantation, with the use of four different devices.

Histological aspects of the saphenous vein damage with the use of the Symmetry aortic connector system.

The purpose of the present study was to analyze the histological aspects of the saphenous veins after the use of the Symmetry aortic connector in off pump coronary artery bypass surgery (OPCAB). Nineteen consecutive patients who underwent OPCAB surgery and who received one proximal saphenous vein anastomosis using the St Jude aortic Symmetry connector system were evaluated. In each patient one small segment of the saphenous vein was cut before the use of the Symmetry connector (V0), then another segment after (V1).

Extracorporeal life support in right ventricular rupture secondary to blast injury.

Nowadays, indications of extracorporeal life support (ECLS) are increasing. We here describe a case of right ventricular rupture requiring challenging sutures. We installed an ECLS to re-establish the haemodynamic conditions and to discharge the ruptured right ventricle, permitting us to suture it.

Acute pulmonary embolism: a current surgical approach.

Acute massive pulmonary embolism has a high mortality rate despite advances in diagnosis and therapy. Thrombolysis and catheter embolectomy have recently shown various degrees of failure and adverse effect. Surgical embolectomy has now been liberalised for haemodynamic stable patients with right ventricular dysfunction.