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Starting from a reformulation of the mass balance law based on the Bilby–Kröner–Lee (BKL) decomposition of the deformation gradient tensor, we study some peculiar mechanical aspects of growth in a monophasic continuum by regarding the reformulated mass balance equation as a non-holonomic and rheonomic constraint. Such constraint restricts the admissible rates of the growth tensor, i.e., one of the two factors of the BKL decomposition, to comply with a growth law provided phenomenologically. For our purposes, we put the constraint in Pfaffian form, and treat time as a fictitious, additional Lagrangian parameter, subjected to the condition that its rate must be unitary. Then, by taking some suggestions from the literature, we assume the existence of generalized forces conjugated with the virtual variations of the growth tensor, and we write a constrained version of the Principle of Virtual Work (PVW) that leads to a mixed boundary value problem whose unknowns are the motion, the growth tensor, and the Lagrange multipliers of the considered theory. This allows to extrapolate a physical interpretation of the role that the growth-conjugated forces play on the components of the growth tensor, especially on the distortional ones, i.e., those that are not directly related to the variation of mass of the body. The core message of our work is conceptual: we show that the growth laws usually encountered in the literature, which are prescribed phenomenologically, but may be difficult to justify theoretically, can be put in the framework of the PVW by regarding them as constraints. Moreover, we retrieve more particularized frameworks of growth available in the literature, while being able to switch to a theory of growth of grade one, such as a Cahn–Hilliard model of growth.

Apical cannulation of a left ventricle for temporary support is still challenging, especially in case of prolonged support due to donor organ shortage. Traditional cannulation techniques with the cannula being directly inserted into the left ventricle cavity are technically easy, but prone to hemorrhage during circulatory support, unsafe for a prolonged support (over than 30 days) and limits the possibility to ambulate patient due to risk for cannula dislocation and related life-threatening bleeding. We describe a case of temporary left ventricular assist device placement in a 59-year-old male patient being on veno-arterial extracorporeal membrane oxygenation support secondary to acute myocardial infarction. We present a very simple technique to secure insertion of an apical left ventricular cannula using patch of soft Teflon felt. Handmade created apical soft Teflon cuff is than fixed using twelve 4/0 prolene sutures supported with pledgets. This gives better fixation to apical myocardium (especially in case of fragile tissue after acute infarction) and secure intracavitary length of inflow cannula in a controlled mode, thus better than purse-string sutures only. Using anti-adhesive membrane, further dissection during heart transplant procedure was uneventful. This technique allowed safe circulatory support and patient ambulation in the ward during 85 days until heart transplantation.

ObjectiveRecurrent infective endocarditis (IE) is a major complication of patients surviving a first episode of IE. This study sought to analyse the current state of recurrent IE in a large contemporary cohort.Methods1335 consecutive episodes of IE were recruited prospectively in three tertiary care centres in Spain between 1996 and 2015. Episodes were categorised into group I (n=1227), first-IE episode and group II (n=108), recurrent IE (8.1%). After excluding six patients, due to lack of relevant data, group II was subdivided into IIa (n=87), reinfection (different microorganism), and IIb (n=15), relapse (same microorganism within 6 months of the initial episode).ResultsThe cumulative burden and incidence of recurrence was slightly lower in the second decade of the study (2006–2015) (7.17 vs 4.10 events/100 survivors and 7.51% vs 3.82, respectively). Patients with reinfections, compared with group I, were significantly younger, had a higher frequency of HIV infection, were more commonly intravenous drug users (IVDU) and prosthetic valve carriers, had less embolic complications and cardiac surgery, with similar in-hospital mortality. IVDU was found to be an independent predictor of reinfection (HR 3.92, 95% CI 1.86 to 8.28).In the relapse IE group, prosthetic valve endocarditis (PVE) and periannular complications were more common. Among patients treated medically, those with PVE had a higher relapse incidence (4.82% vs 0.43% in native valve IE, p=0.018). Staphylococcus aureus and PVE were independent predictors of relapse (HR 3.14, 95% CI 1.11 to 8.86 and 3.19, 95% CI 1.13 to 9.00, respectively) and in-hospital-mortality was similar to group I. Three-year all-cause mortality was similar in recurrent episodes compared with single episodes.ConclusionRecurrent IE remains a frequent late complication. IVDU was associated with a fourfold increase in the risk of reinfection. PVE treated medically and infections caused by S. aureus increased the risk of relapse. In-hospital and long-term mortality was comparable among groups.

In this work, we contribute to the study of the structural reorganisation of biological tissues in response to mechanical stimuli. We specialise our investigation to a class of hydrated soft tissues, whose internal structure features reinforcing fibres. These are oriented statistically within the tissue, and their pattern of orientation is such that, at each material point, the tissue is anisotropic. From its natural, stress-free state, the tissue can be distorted anelastically into a global reference configuration, and then deformed under the action of external mechanical loads. The anelastic distortions are responsible for changing irreversibly the internal structure of the tissue, which, in the present context, occurs through both the rearrangement of the bonds among the tissue cells and the deformation-driven reorientation of the fibres. The anelastic strains, in addition, are assumed to model the onset and evolution of microcracks in the tissue, which may be triggered by the mechanical loads applied to the tissue in the case of traumatic events, or diseases. For our purposes, we formulate an anisotropic model of remodelling and we consider a fully isotropic model of structural reorganisation for comparison, with the aim to study if, how, and to what extent the evolution of anelastic distortions is influenced by the tissue’s anisotropy.

Starting from the observation that the growth of a body breaks the time translation symmetry of the body’s dynamics, we determine a scalar field, called internal time, that defines an indicator of the intrinsic time scale of the growth-related body’s structural evolution. By recasting the theory of growth for monophasic media within a variational framework, we obtain the internal time as the solution of a partial differential equation descending from Noether’s Theorem. We do this by considering two approaches, one formulated in terms of internal variables and one adopting the concept of augmented kinematics.

The availability and evolution of chemical agents play an important role in the growth of a tumour and, therefore, the mathematical description of their consumption is of special interest. Usually, Fick’s law of diffusion is adopted for describing the local character of the evolution of chemicals. However, in a highly complex, heterogeneous medium, as is a tumour, the progression of chemical species could be influenced by non-local interactions. In this respect, our goal is to investigate the influence of such types of diffusion on the growth of a tumour in the avascular stage. For our purposes, we consider a diffusion equation for the evolution of the chemical agents that accounts for the existence of non-local interactions in a non-Fickean manner, and that involves notions of fractional calculus. In particular, the introduction of derivatives or integrals of fractional type of order [Formula: see text] has proven to be an effective mathematical tool in the description of various non-local phenomena. To achieve our goals, we adopt part of the modelling assumptions outlined in previous works, in which the growth of a tumour is described in terms of mass transfer among the tumour’s constituents and structural changes that occur in the tumour itself in response to growth. The latter ones are characterised by means of the Bilby–Kröner–Lee decomposition of the deformation gradient tensor. We perform numerical simulations, whose results indicate the relevance of embracing a fractional framework in modelling tumour growth. Specifically, the real parameter [Formula: see text]‘dominates’ the way in which the tumour grows, since it permits the modelling of a variety of growth patterns ranging from the standard growth to no growth at all.

This work concerns the study of the effective balance equations governing linear elastic electrostrictive composites, where mechanical strains can be observed due to the application of a given electric field in the so-called small strain and moderate electric field regime. The formulation is developed in the framework of the active elastic composites. The latter are defined as composite materials constitutively described by an additive decomposition of the stress tensor into a purely linear elastic contribution and another component, which is assumed to be given and quadratic in the applied electric field when further specialised to electrostrictive composites. We derive the new mathematical model by describing the effective mechanical behaviour of the whole material by means of the asymptotic (periodic) homogenisation technique. We assume that there exists a sharp separation between the micro-scale, where the distance among different sub-phases (i.e. inclusions and/or fibres and/or strata) is resolved, and the macro-scale, which is related to the average size of the whole system at hand. This way, we formally decompose spatial variations by assuming that every physical field and material property are depending on both the macro-scale and the micro-scale. The effective governing equations encode the role of the micro-structure, and the effective contributions to the global stress tensor are to be computed by solving appropriate linear-elastic-type cell problems on the periodic cell. We also provide analytic formulae for the electrostrictive tensor when the applied electric field is either microscopically uniform or given by a suitable multiplicative decomposition between purely microscopically and macroscopically varying components. The obtained results are consistently compared with previous works in the field, and can pave the way towards improvement of smart active materials currently utilised for engineering (possibly bio-inspired) purposes.

Background and aim of the study In 2009 our group described a new surgical technique for patients with severe mitral valve calcification undergoing mitral valve surgery. This technique creates a new mitral annulus with plication of the mitral leaflet and the atrial wall. Our objective is to report the long-term results of the experience at our institution. Materials, methods, and results From 2007 to 2016, a total of 18 patients (mean age 70.5 ± 7.8 years) underwent mitral valve replacement at our institution with this technique. One patient died on the second postoperative day. Clinical and echocardiographic in-hospital and long-term follow-up (55.5 ± 40.4 months) were performed on all the remaining 17 patients. Functional improvement was achieved in all patients. Two patients died 6 and 8 years after surgery (cancer and hemorrhagic stroke). No prosthetic dysfunction, periprosthetic leak, or annular dehiscence were detected in the long-term echocardiographic examinations. Conclusions The reconstruction of the mitral annulus by using our technique in patients with severe calcification of the mitral annulus has low long-term mortality, good functional results, and a lack of prosthetic complications.

Motivated by the increasing interest of the biomechanical community towards the employment of strain‐gradient theories for solving biological problems, we study the growth and remodeling of a biological tissue on the basis of a strain‐gradient formulation of remodeling. Our scope is to evaluate the impact of such an approach on the principal physical quantities that determine the growth of the tissue. For our purposes, we assume that remodeling is characterized by a coarse and a fine length scale and, taking inspiration from a work by Anand, Aslan, and Chester, we introduce a kinematic variable that resolves the fine scale inhomogeneities induced by remodeling. With respect to this variable, a strain‐gradient framework of remodeling is developed. We adopt this formulation in order to investigate how a tumor tissue grows and how it remodels in response to growth. In particular, we focus on a type of remodeling that manifests itself in two different, but complementary, ways: on the one hand, it finds its expression in a stress‐induced reorganization of the adhesion bonds among the tumor cells, and, on the other hand, it leads to a change of shape of the cells and of the tissue, which is generally not recovered when external loads are removed. To address this situation, we resort to a generalized Bilby‐Kroner‐Lee decomposition of the deformation gradient tensor. We test our model on a benchmark problem taken from the literature, which we rephrase in two ways: microscale remodeling is disregarded in the first case, and accounted for in the second one. Finally, we compare and discuss the obtained numerical results.

Multicellular aggregates are an excellent model system to explore the role of tissue biomechanics, which has been demonstrated to play a crucial role in many physiological and pathological processes. In this paper, we propose a three-dimensional mechanical model and apply it to the uniaxial compression of a multicellular aggregate in a realistic biological setting. In particular, we consider an aggregate of initially spherical shape and describe both its elastic deformations and the reorganisation of the cells forming the spheroid. The latter phenomenon, understood as remodelling, is accounted for by assuming that the aggregate undergoes plastic-like distortions. The study of the compression of the spheroid, achieved by means of two parallel, compressive plates, needs the formulation of a contact problem between the living spheroid itself and the plates, and is solved with the aid of the augmented Lagrangian method. The results of the performed numerical simulations are in qualitative agreement with the biological observations reported in the literature and can also be used to estimate quantitatively some fundamental aggregate mechanical parameters.

We highlight some mechanical aspects of the coupling among deformation, fluid flow, structural evolution, and reorientation of fibres in fibre-reinforced, hydrated, soft biological tissues. For our purposes, we elaborate a model in which the tissue’s interstitial fluid is inviscid and obeys Darcy’s law, and the solid constituents are transversely isotropic, hyperelastic materials. Within this setting, we consider two different types of remodelling: One consists of the reorientation of the fibres, while the other one is the manifestation, at the tissue scale, of structural rearrangements representable in terms of inelastic distortions. Our focus is on the interplay between the latter ones and the fibre reorientation. In our model, such interplay is a consequence of the constitutive framework, which resolves explicitly the space variability of a parameter, the “fibre mean angle”, that determines the direction along which the fibres tend to align themselves. Our main results concern the description of a Mandel-like stress tensor, which drives the inelastic distortions when the fibre mean angle is distributed inhomogeneously throughout the tissue, and of a diffusion-like tensor depending on the inelastic distortions, which guides the evolution of the fibre mean angle.

Background We aimed to analyze causes, management, and outcomes of the unexpected need to abort sternotomy in aortic stenosis (AS) patients accepted for surgical aortic valve replacement (SAVR) in the transcatheter aortic valve implantation (TAVI) era. Methods Cases of aborted sternotomy (AbS) were gathered from 5 centers between 2009 and 2014. A systematic review of all published cases in the same period was performed. Results A total of 31 patients (71% males, 74±8years, LogEuroSCORE 11.9±7.4%) suffered an AbS (0.19% of all sternotomies). Main reasons for Abs included previously unknown porcelain aorta (PAo) in 83.9%, mediastinal fibrosis due to radiotherapy in 12.9%, and chronic mediastinitis in 3.2%. Median time between AbS and next intervention was 2.3months (IQR: 0.7–5.8) with no mortality within this period. Only a case was managed with open surgery. In 30 patients (96.8%) TAVI was performed with a rate of success of 86.7%. Three patients (9.7%) presented in-hospital death and 17 (54.8%) had in-hospital complications including heart failure (9.6%), major bleeding (6.9%), and acute kidney injury (9.6%). Older patients (76±8 vs. 70±8years, p=0.045), previous cardiac surgery (60% vs. 15.4%, p=0.029), and shorter time from AbS to next intervention (5.1±5 vs. 1±0.7months, p=0.001) were related to higher six-month mortality (22.6%). Conclusions The main reason for AbS was PAo. This entity was associated to a higher rate of complications and mortality, especially in older patients and with prior cardiac surgery. A preventive strategy in these subgroups might be based on imaging evaluation. TAVI was the most extended therapy.

BACKGROUND The culture of removed cardiac tissues during cardiac surgery of left-sided infective endocarditis (LSIE) helps to guide antibiotic treatment. Nevertheless, the prognostic information of a positive valve culture has never been explored. METHODS Among 1078 cases of LSIE consecutively diagnosed in 3 tertiary centers, we selected patients with positive blood cultures who underwent surgery during the active period of infection and in whom surgical biological tissues were cultured (n = 429). According to microbiological results, we constructed 2 groups: negative valve culture (n=218) and concordant positive valve culture (CPVC) (n=118). We compared their main features and performed a multivariable analysis of in-hospital mortality. RESULTS Patients with CPVC presented more nosocomial origin (32% vs 20%, P = .014), more septic shock (21% vs 11%, P = .007), and higher Risk-E score (29% vs 21%, P = .023). Their in-hospital mortality was higher (35% vs 19%, P = .001), despite an earlier surgery (3 vs 11 days from antibiotic initiation, P < .001). Staphylococcus species (61% vs 42%, P = .001) and Enterococcus species (20% vs 9%, P = .002) were more frequent in the CPVC group, whereas Streptococcus species were less frequent (14% vs 42%, P < .001). Independent predictors for in-hospital mortality were renal failure (odds ratio [OR], 2.6 [95% confidence interval {CI}, 1.5-4.4]), prosthesis (OR, 1.9 [95% CI, 1.1-3.5]), Staphylococcus aureus (OR, 1.8 [95% CI, 1.02-3.3]), and CPVC (OR, 2.3 [95% CI, 1.4-3.9]). CONCLUSIONS Valve culture in patients with active LSIE is an independent predictor of in-hospital mortality.

Background To assess the efficacy and safety of intramyocardial autologous bone marrow mononuclear stem cells (BMMNC) grafting combined with coronary artery bypass grafting (CABG) on ventricular remodeling and global and regional wall motion after acute transmural myocardial infarction (AMI). Methods Randomized controlled trial including 20 patients with non-revascularized transmural AMI, left ventricular ejection fraction (LVEF) lower than 50% and surgical indication for CABG. The stem cell group was treated with BMMNC grafting by direct intramyocardial injection between the 10th and 15th days after AMI (subacute phase) combined with CABG under cardiopulmonary bypass; the control group was only treated with CABG. Magnetic resonance imaging with gadolinium and stress echocardiography were performed presurgery and 9 months postsurgery. Results Seventeen patients completed the follow-up. The baseline characteristics of both groups were homogeneous. No significant differences were found in the increase in LVEF (control: 6.99±4.60, cells: 7.47±6.61, P=0.876) or in the decrease in global (control: 0.28±0.39, cells: 0.22±0.28, P=0.759) or regional (control: 0.52±0.38, cells: 0.74±0.60, P=0.415) wall motion indices between the control and stem cell groups of AMI patients. No differences were found in the recovered non-viable segments (control: 1.29±1.11, cells: 2.50±1.41, P=0.091) or in the decrease in end-diastolic (control: 14.05±19.72, cells: 18.40±29.89, P=0.725) or end-systolic (control: 15.42±13.93, cells: 23.06±25.03, P=0.442) volumes. No complications from stem cell grafting were observed. Conclusions The results from our study reported herein suggest that intramyocardial BMMNC administration during CABG in patients with AMI causes no medium- to long-term improvement in ventricular remodeling.

OBJECTIVES Acute onset of infective endocarditis has been previously linked to the development of septic shock and a worse prognosis. The purpose of this study was to analyse the clinical features and in-hospital evolution of patients with acute-onset endocarditis as well as the potential role of early surgery in the treatment of these patients. METHODS From 1996 to 2014, 1053 consecutive patients with left-sided endocarditis were prospectively included. Patients were classified into 2 groups according to the clinical presentation: patients with acute-onset endocarditis (n = 491) and patients with non-acute endocarditis (n = 562). Acute-onset endocarditis was considered when the time between the appearance of symptoms and diagnosis was

In the present work, we apply the asymptotic homogenization technique to the equations describing the dynamics of a heterogeneous material with evolving micro-structure, thereby obtaining a set of upscaled, effective equations. We consider the case in which the heterogeneous body comprises two hyperelastic materials and we assume that the evolution of their micro-structure occurs through the development of plastic-like distortions, the latter ones being accounted for by means of the Bilby–Kroner–Lee (BKL) decomposition. The asymptotic homogenization approach is applied simultaneously to the linear momentum balance law of the body and to the evolution law for the plastic-like distortions. Such evolution law models a stress-driven production of inelastic distortions, and stems from phenomenological observations done on cellular aggregates. The whole study is also framed within the limit of small elastic distortions, and provides a robust framework that can be readily generalized to growth and remodeling of nonlinear composites. Finally, we complete our theoretical model by performing numerical simulations.

We reformulate a model of avascular tumour growth in which the tumour tissue is studied as a biphasic medium featuring an interstitial fluid and a solid phase. The description of growth relies on two fundamental features: one of those is given by the mass transfer among the constituents of the phases, which is taken into account through source and sink terms; the other one is the multiplicative decomposition of the deformation gradient tensor of the solid phase, with the introduction of a growth tensor, which represents the growth-induced structural changes of the tumour. In general, such tensor is non-integrable, and it may allow to define a Levi-Civita connection with non-trivial curvature. Moreover, its evolution is related to the source and sink of mass of the solid phase through an evolution equation. Our goal is to study how growth can be influenced by the inhomogeneity of the growth tensor. To this end, we study the evolution of the latter, as predicted by two different models. In the first one, the dependence of the growth tensor on the tumour’s material points is not explicitly considered in the evolution equation. In the second model, instead, the inhomogeneity of the growth tensor is resolved explicitly by introducing the curvature associated with it into the evolution equation. We perform numerical simulations to compare the results produced by these two models, and evaluate a possible role of the material inhomogeneities on growth.

International audience; Objective To develop and validate a calculator to predict the risk of in-hospital mortality in patients with active infective endocarditis (IE) undergoing cardiac surgery. Methods Thousand two hundred and ninety-nine consecutive patients with IE were prospectively recruited (1996-2014) and retrospectively analysed. Left-sided patients who underwent cardiac surgery (n=671) form our study population and were randomised into development (n=424) and validation (n=247) samples. Variables statistically significant to predict in-mortality were integrated in a multivariable prediction model, the Risk-Endocarditis Score (RISK-E). The predictive performance of the score and four existing surgical scores (European System for Cardiac Operative Risk Evaluation (EuroSCORE) I and II), Prosthesis, Age >= 70, Large Intracardiac Destruction, Staphylococcus, Urgent Surgery, Sex (Female) (PALSUSE), EuroSCORE >= 10) and Society of Thoracic Surgeons's Infective endocarditis score (STS-IE)) were assessed and compared in our cohort. Finally, an external validation of the RISK-E in a separate population was done. Results Variables included in the final model were age, prosthetic infection, periannular complications, Staphylococcus aureus or fungi infection, acute renal failure, septic shock, cardiogenic shock and thrombocytopaenia. Area under the receiver operating characteristic curve in the validation sample was 0.82 (95% CI 0.75 to 0.88). The accuracy of the other surgical scores when compared with the RISK-E was inferior (p=0.010). Our score also obtained a good predictive performance, area under the curve 0.76 (95% CI 0.64 to 0.88), in the external validation. Conclusions IE-specific factors (microorganisms, periannular complications and sepsis) beside classical variables in heart surgery (age, haemodynamic condition and renal failure) independently predicted perioperative mortality in IE. The RISK-E had better ability to predict surgical mortality in patients with IE when compared with other surgical scores.

OBJECTIVE: The aim of this study was to evaluate the midterm results of the reimplantation technique with a straight tubular graft in patients with aortic root aneurysms with or without aortic insufficiency. METHODS: From February 2002 to November 2012, 51 consecutive patients underwent the David I valve-sparing aortic procedure for aortic root aneurysm; the mean age was 59.9±12.3 years. Nine patients (17.6%) had a bicuspid aortic valve. Patients were followed prospectively for 4.78±3.60 years (median, 5 years). Operative results, survival, freedom from redo aortic surgery and from recurrent aortic insufficiency greater than 2+ were assessed. RESULTS: No in-hospital mortality was recorded. In 5 cases, adjunctive procedures on the aortic valve were needed to achieve good leaflet coaptation. Aortic regurgitation was significantly lower at discharge (2.3±1.0 vs 0.3±0.5; P

Background: Recently, the use of transcatheter aortic valve implantation (TAVI) in inter­mediate-low risk patients has been evaluated in the PARTNER II randomized trial. However, in the last years, this therapy has been employed in this scenario with underreported results, as compared to surgical aortic valve replacement (SAVR). Methods: We enrolled 362 consecutive patients with severe symptomatic aortic stenosis and intermediate-low surgical risk (logEuroSCORE < 20%), treated in our center with TAVI (103 patients) or single SAVR (259 patients) between 2009 and 2014. Patients were matched according to age, gender, logEuroSCORE, and use of bioprosthesis. Results: Mean age of the patients was 73 ± 10.4 years, and 40.3% were women. LogEuroSCORE and Society Thoracic Surgeons score were 7.0 ± 4.4% and 4.2 ± 2.5%, respectively, with mean left ventricular ejection fraction of 52 ± 9%. There were no differences regarding other comorbidities. The length-of-hospitalization was 11 ± 5 days after TAVI vs. 17 ± 9 days after SAVR (p = 0.003). After matched comparison, no differences in terms of in-hospital mortality (5.7% after TAVI vs. 2.9% after SAVR, p = 0.687) and 1-year mortality (11.4% vs. 7.1%, p = 0.381) were found. The combined endpoint of stroke and mortality at 1-year was also similar between both groups (15.7% in TAVI patients vs. 14.4% after SAVR, p = 0.136). Multivariate analysis determined that aortic regurgitation (AR) was an independent predictor of mortality (OR = 3.623, 95% CI: 1.267–10.358, p = 0.016). Although the rate of AR was higher after TAVI, none of the patients treated with the newest generation devices (10.7%) presented more than a mild degree of AR. Conclusions: TAVI is feasible and shows comparable results to surgery in terms of early, 1-year mortality, as well as cerebrovascular events in patients with severe aortic stenosis and intermediate-low operative risk. Better transvalvular gradients, yet higher rates of AR were found, however, newer devices presented comparable rate of AR.

Aims: We aimed to develop a new simple angiographic score that would predict short- and mid-term patency problems of coronary artery bypass grafts (CABG). Methods: We enrolled 249 patients who underwent CABG. The Distal Vessel Quality (DVQ) score was calculated according to 1/visibility, 2/diameter, and 3/size of the distal vessel as angiographically evaluated at baseline. Each variable was quantified from 0 (worst) to 3 (best) and the DVQ score resulted from the addition of these values. Results: At 5-year of follow-up 16% of the patients had been admitted due to a coronary event and, after angiography, occlusion of 67 grafts (9.2%) was demonstrated (median time from surgery: 1.4 [IQR: 0.5-1.7] years). In 67% of the cases, a diseased graft was the responsible for the event. Venous grafts were 2.5 times more frequently occluded than arterial grafts (p=0.098). Indeed, the use of arterial grafts (OR=0.217, 95% CI [0.064-0.737], p=0.014) and higher values of DVQ score (OR=0.555, 95% CI [0.370-0.832], p=0.004) were independent predictors of bypass graft patency at 5-year follow-up. To remark, bad correlation of DVQ and syntax scores was found (R=0.228) and the last failed to predict the risk of early graft malfunction. Conclusions: The DVQ score is a new simple tool that may help to predict outcomes of coronary bypass grafts. Lower values of this score suggest limited benefit of bypass grafting. Therefore, the DVQ score could help to improve outcomes of cardiac surgery by improving the selection of patients. External validation of these results is warranted.

An 18-year-old man without a medical history was admitted to our hospital with pericarditic thoracic pain, fever, leukocytosis, and elevated cardiac enzymes. ECG showed a second-degree atrioventricular block, and transthoracic echocardiogram revealed a severe pericardial effusion (30 mm; Figure 1A). Because of signs and symptoms of cardiac tamponade, subxifoid pericardiocentesis was successfully performed, and a cloudy liquid was obtained. Empirical antibiotics were prescribed despite blood. Pericardial effusion and urine cultures were sterile because of the biochemical characteristics of the pericardial effusion. Viral serologies and Mantoux were also negative, and autoimmune disorders were ruled out. Cardiac magnetic resonance demonstrated an epicardial 21-mm-thick solid mass with homogeneous aspect, starting in the left ventricle and extending …

Left-sided infective endocarditis (LSIE) bears a high in-hospital mortality rate that has remained unchanged over the past 2 decades [(1)][1]. Our objectives were to investigate whether the clinical profile of patients with LSIE has worsened in this time period and to test the hypothesis that this

Introduccion y objetivos La morbimortalidad de la cirugia cardiaca parece ser mayor en los pacientes neoplasicos. Los fenomenos inflamatorios y las reacciones inmunitarias secundarias a la circulacion extracorporea pueden favorecer la recidiva tumoral. Evaluamos las caracteristicas y los resultados de la cirugia cardiaca en nuestros pacientes oncologicos. Metodos De 2.146 pacientes consecutivos sometidos a circulacion extracorporea, 89 (4,2%) presentaban una neoplasia. El cancer estaba activo (recientemente diagnosticado o en tratamiento) en 33 pacientes (grupo A) y en remision completa en 56 (grupo B). Se pareo ambos grupos con 165 pacientes sin tumor similares en edad, sexo, tipo de cirugia y comorbilidad (grupo C). Evaluamos retrospectivamente los factores de riesgo de morbimortalidad quirurgica, supervivencia y recidiva tumoral. Resultados La mediana del intervalo entre diagnostico del cancer y cirugia fue de 60 meses, con mortalidad y morbilidad hospitalarias del 4,5 y el 36%, respectivamente, frente al 5,4 y el 32,7% en el grupo C. Durante el seguimiento, fallecieron 12 pacientes (8 por causa tumoral), 16 sufrieron recidiva y 2, tumores nuevos. El analisis estadistico no permitio identificar ningun factor de riesgo de mortalidad. La morbilidad postoperatoria aumento en pacientes con insuficiencia renal. Durante el seguimiento, la supervivencia disminuyo significativamente en el grupo A en caso de disfuncion ventricular izquierda preoperatoria y enfermedad pulmonar obstructiva cronica y cuando el intervalo entre diagnostico de cancer y cirugia fue Conclusiones No hemos observado un incremento en la morbimortalidad de la cirugia cardiaca en pacientes oncologicos. No obstante, la supervivencia disminuye en neoplasias activas o de diagnostico reciente.

Introduction and objectives Morbimortality related to cardiac surgery may be superior in patients with malignancy neoplastic disease. Inflammatory phenomena and immunologic changes secondary to extracorporeal circulation use can also increase tumor recurrence. We evaluate characteristics and results of cardiac surgery in our neoplastic patients. Methods Out of 2146 consecutive patients who underwent cardiac surgery with extracorporeal circulation, 89 (4.2%) had been previously affected by cancer. Cancer was active (recent diagnosis or under treatment) in 33 patients (group A) and in 56 (group B) were in remission. Both groups were matched with 165 patients with no tumor, according to age, gender, type of surgery, and comorbidity (group C). We retrospectively evaluated incremental risk factors for surgical morbimortality, survival, and tumor recurrence. Results Median interval between cancer diagnosis and surgery was 60 months and mortality and morbidity were 4.5% and 36%, respectively, versus 5.4% and 32.7% in group C. During follow-up, 12 patients died (8 due to cancer), 16 suffered cancer recurrence, and 2 new tumors were diagnosed. Statistical analysis did not permit us to identify any incremental risk factor for mortality. Postoperative morbidity was increased in case of preoperative renal failure. During follow-up, survival was significantly decreased in group A, in case of preoperative left ventricular dysfunction or obstructive pulmonary disease, and when interval between cancer diagnosis and cardiac surgery was under 2 years. Conclusions We have not observed an increase in cardiac surgery morbimortality in cancer patients. Anyway, survival is decreased in case of active or recently diagnosed cancer.

We designed a pilot study to assess as primary end point the safety and efficacy of a new phosphorylcholine-coated, closed cardiopulmonary bypass (CPB) system (extracorporeal circulation, optimized [ECC.O], Dideco, Mirandola, Italy). The secondary end point was to compare results with two retrospectively matched cohorts of patients who underwent isolated coronary artery by-pass graft (CAGB) with nonphosphorylcholine-bonded circuits and cardiotomy suction (Group II, n = 32) and off-pump coronary artery by-pass (OPCAB) (Group III, n = 26). In January 2005, 30 patients (Group I) undergoing first-time CABG were assigned to the ECC.O group. Five minutes after CPB, initial hematocrit levels were significantly and consistently highest in Group I relative to Group II (Group I, 29.7 +/- 4.4 vs. Group II, 22.7 +/- 4.1; P < 0.001). Red blood cell transfusion rate was reduced drastically in Group I versus Group II (P < 0.001). High differences were also observed in C-reactive protein levels at 24 h after surgery (Group I vs. Group II-P < 0.001 and vs. Group III-P < 0.001) and at 72-h peak value (Group I vs. Group II-P < 0.001 and vs. Group III-P < 0.001). The routine clinical use of the ECC.O system has been demonstrated to be both clinically safe and efficacious. An intensive training program for surgeons, perfusionists, and anesthesiologists is required.

All types of cardiac surgery involve considerable injury to the myocardium. However, it is difficult to differentiate, in the immediate post-operative state, between ischemic alterations associated with the cardiac surgery itself and the pathological alterations of a peri-operative myocardial infarction. The diagnosis of damaged myocardium, classically performed with the enzymatic markers creatine kinase (CK) and its muscle fraction (CK-MB), has become more precise with the option of measuring cardiac troponins T and I. We measured these markers in 58 patients undergoing elective cardiac surgery with extra-corporeal circulation (ECC). The patients included 37 cases undergoing valve surgery, 14 for coronary revascularization, 6 for mixed procedures, and 1 for closure of an inter-atrial communication. The markers were measured in plasma at baseline (at anesthesia initiation), 5 min post-ECC commencement, following aorta de-clamping, during the surgical closure, and 6, 18 and 42 hrs after surgery. All the markers were increased significantly relative to the baseline values. Troponin I, CK and CK-MB values peaked between 6 and 18 hrs after surgery, troponin T between 18 and 42 hrs, and myoglobin at the surgical closure. The values of all markers were higher in patients undergoing coronary surgery compared to those in patients undergoing valve surgery. In the evaluation of myocardial damage after surgery, the measurement of classical markers such as CK and myoglobin remain valid, but other markers such as troponins provide significant additional diagnostic benefit and, thus, need to be included in the routine biochemical measurements for monitoring myocardial damage associated with the surgical procedure.

Despite optimal hemodynamics at rest, the performance of the aortic valve under stress conditions long after David I procedure is still debated. From 2001-2014, 73 patients underwent reimplantation with David I technique. Aortic valve function of 13 patients (age 61.2 ± 8.72) with a follow-up of at least 5 years (6.3 ± 0.9 years) was assessed at exercise echocardiographic stress test on a stationary cycle. Patients who had undergone concomitant procedure, with recurrent aortic insufficiency or mitral valve incompetence, were excluded. In all, 8 healthy volunteers served as controls. Transvalvular gradients progressively increased during the steps in both groups (P-within < 0.001), being higher in David patients (P-between < 0.001), but never reaching a clinical significance (David Peak gradient 23.8 ± 9.3 mmHg; Mean gradient 13.2 ± 5.1 mmHg). Effective orifice area (EOA) and EOA index did not change during the test in David patients, whereas Controls showed a progressive increase of functional valve area to a peak at 50 W (Controls EOA 4.0 ± 0.5 cm(2); EOA index 2.0 ± 0.3 cm(2)/m(2)). In conclusion, David I procedure ensures good hemodynamics during high-flow conditions at long-term follow-up. The reimplantation of the functional aortic annulus inside a rigid tube determines a paradoxical reduction of functional aortic valve area, secondary to the increased stroke volume, without any clinically relevant increase in transvalvular gradients. These data confirm the reliability of David I in the long term, even under physical stress conditions.

Aims Surgery in patients with infective endocarditis (IE) can be elective (upon completion of antibiotic treatment) or urgent (before antibiotic treatment has ended) when the clinical course is unfavourable. However, urgent surgery for left-sided endocarditis is associated with high mortality. The aims of this study were to describe the profile of patients with left-sided endocarditis who underwent urgent surgery and to analyse the factors that predicted mortality. Methods and results Among 508 consecutive episodes of IE, 391 were left-sided and 89 required urgent surgery. The main reasons for urgent surgery were heart failure that did not respond to medication (72%) and persistent infection despite appropriate antibiotic treatment (31%). Thirty-two patients (36%) died during their hospital stay. Univariate analysis identified renal failure, septic shock, Gram-negative bacteria, persistent infection, and surgery for persistent infection as factors associated with mortality. Multivariate analysis confirmed only persistent infection and renal insufficiency as factors independently associated with a poor prognosis. Conclusion Patients with IE who need urgent surgery have a poor clinical course. Heart failure, the main cause of urgent surgery, was not associated with higher mortality. However, persistent infection and renal failure were factors associated with higher post-surgical mortality.

OBJECTIVES Neuropsychological dysfunction is a recognized complication after cardiac surgery. Attention, concentration, short term memory, and speed of mental processing are commonly involved. We evaluated prospectively the incidence of cognitive impairment in our population using a single test: Paced Auditory Serial Addition Test. METHODS We analysed 132 patients (mean age 67 years) undergoing elective cardiac surgery (63.6% valvular, 25% coronary artery bypass grafting and rest mixed procedures) between January and June 2003. We did not include patients with previous history of cognitive impairment, major psychiatric disorders or stroke. Paced Auditory Serial Addition Test was performed before and after surgery (mean, 7 days) and in outpatient follow-up (mean, 4 months). RESULTS None of the patients suffered a major neurological complication. Mean preoperative Paced Auditory Serial Addition Test score was 27.04+/-11.05, 25.81+/-11.83 in immediate postoperative and 27.93+/-13.11 in follow-up. A significant postoperative neuropsychological dysfunction (test scale decline more than 1 S.D.) was shown in 45.5% of the patients. In 48.8%, decline persisted in follow-up. Valvular surgery and low preoperative Paced Auditory Serial Addition Test score were significant risk factors for immediate postoperative neuropsychological dysfunction. Valvular surgery and female sex were significant in multivariable analysis. Considering follow-up, older age is the only significant risk factor for cognitive impairment. CONCLUSIONS Using a single, quantifiable and easy and quickly applied test such as the Paced Auditory Serial Addition Test, we found an incidence of cognitive decline after cardiac surgery similar to that previously described. Valvular surgery and older age are the main risk factors for neuropsychological dysfunction in our population.