Andres Beiras-Fernandez

Three-dimensional printing of models for preoperative planning and simulation of transcatheter valve replacement.

In this study, we show the use of three-dimensional printing models for preoperative planning of transcatheter valve replacement in a patient with an extreme porcelain aorta. A 70-year-old man with severe aortic stenosis and a porcelain aorta was referred to our center for transcatheter aortic valve replacement. Unfortunately, the patient died after the procedure because of a potential ischemic event. Therefore, we decided to fabricate three-dimensional models to evaluate the potential effects of these constructs for previous surgical planning and simulation of the transcatheter valve replacement.

Relationship of a common polymorphism of the glucocorticoid receptor gene to traumatic memories and posttraumatic stress disorder in patients after intensive care therapy.

Objective:Glucocorticoids play a major role in the consolidation and retrieval of traumatic information. They act through the glucocorticoid receptor, for which, in humans, several polymorphisms have been described. In particular, the BclI single-nucleotide polymorphism is associated with hypersensitivity to glucocorticoids and with susceptibility to development of major depression. Furthermore, in patients with posttraumatic stress disorder carrying the BclI GG genotype, cortisol levels were lower and showed an inverse relationship to posttraumatic stress disorder symptom intensity. Here, we studied the association of the BclI polymorphism with plasma cortisol levels, traumatic memories, posttraumatic stress disorder symptoms, and health-related quality of life outcomes in 126 patients undergoing cardiac surgery and intensive care unit therapy. Design:Prospective observational study. Setting:Cardiovascular intensive care unit in a university hospital. Patients:A total of 126 patients undergoing cardiac surgery and intensive care unit treatment. Interventions:No interventions were performed. Measurements and Main Results:Validated questionnaires were used to quantify end points. Measurements were taken 1 day before and 1 wk and 6 months after cardiac surgery. Homozygous carriers of the BclI G allele (n = 21) had significantly lower preoperative plasma cortisol levels and more long-term traumatic memories from intensive care unit therapy at 6 months after cardiac surgery than heterozygous carriers or noncarriers (1.9 ± 1.4 vs. 1.0 ± 1.2, p = .01). Anxiety was significantly more common as a long-term traumatic memory in homozygous BclI G allele carriers than in heterozygous carriers or noncarriers (57% vs. 35%, p = .03). Posttraumatic stress disorder symptom scores were significantly higher at discharge from the intensive care unit in homozygous BclI G allele carriers than in heterozygous carriers or noncarriers. Only heterozygous carriers or BclI G allele noncarriers had a significant gain in health-related quality of life physical function at 6 months after cardiac surgery (p < .01). Baseline values were not statistically different between carriers of the different BclI alleles. Conclusion:Homozygous BclI G allele carriers are at risk for traumatic memories, posttraumatic stress disorder symptoms, and lower health-related quality of life after cardiac surgery and intensive care unit therapy. The BclI single-nucleotide polymorphism may help to identify individuals at need for tailored medical care.

Clinical experience with daptomycin in Europe: the first 2.5 years

Objectives To describe the patient populations and infections being treated with daptomycin, as well as the efficacy and safety outcomes. Patients and methods Data from the European Cubicin Outcomes Registry and Experience (EU-CORESM), retrospectively collected at 118 institutions between January 2006 and August 2008, were analysed. Results Daptomycin treatment was documented in 1127 patients with diverse infections, including complicated skin and soft tissue infections (33%), bacteraemia (22%), endocarditis (12%) and osteomyelitis (6%). It was used empirically, before microbiological results became available, in 53% of patients. Staphylococcus aureus was the most common pathogen (34%), with 52% of isolates resistant to methicillin; coagulase-negative staphylococci and enterococci were also frequent, with 22% of Enterococcus faecium isolates resistant to vancomycin. Daptomycin was used as first-line therapy in 302 (27%) patients. When used second line, the most common reasons for discontinuation of previous antibiotic were treatment failure and toxicity or intolerance. The use of concomitant antibiotics was reported in 65% of patients. Most frequent doses were 6 mg/kg (47%) and 4 mg/kg (32%). The median duration of daptomycin therapy was 10 days (range 1–246 days) in the inpatient setting and 13 days (range 2–189 days) in the outpatient setting. The overall clinical success rate was 79%, with a clinical failure rate of <10% for all infection types. Low failure rates were observed in first- and second-line therapy (6% and 8%, respectively). Daptomycin demonstrated a favourable safety and tolerability profile regardless of treatment duration. Conclusions Daptomycin has a relevant role in the treatment of Gram-positive infections.

In vivo visualization of the effect of polyclonal antithymocyte globulins on the microcirculation after ischemia/reperfusion in a primate model.

Background. Ischemia-reperfusion injury (IRI) leads to increased leukocyte adherence enhancing acute cellular rejection and microvascular dysfunction. Polyclonal antithymocyte globulins (ATGs) induce T-cell depletion and functional impairment of nondepleted lymphocytes in peripheral blood. ATGs represent an important option in the treatment of acute cellular rejection but little is known about their effects on the microcirculation in IRI. Methods. In a perfusion system, 19 cynomolgus monkeys were used to evaluate the influence of three different ATGs on the leukocyte-endothelium interaction after cold ischemia. ATGs were administered to human blood 30 min prior to reperfusion of primate extremities. Using intravital fluorescence microscopy the postreperfusion microcirculation of skeletal muscle was visualized. Results. Significant differences were found between ATG-treated and ATG-free groups concerning blood flow velocity, leukocyte count, and leukocyte-endothelium interaction. ATGs reduced microvascular leukocyte adhesion, count, and blood flow impairment. Conclusion. ATGs have a favorable impact on early mechanisms of IRI. Due to reduced leukocyte adherence to the antigen-presenting endothelial cells, recognition events cannot take place in the posttransplant period of reperfusion. In addition to inhibiting acute transplant rejection, increase of posttransplant blood flow supports the use of ATGs as pretransplant induction therapy.

Stress doses of hydrocortisone in high-risk patients undergoing cardiac surgery: effects on interleukin-6 to interleukin-10 ratio and early outcome.

Background:Severe systemic inflammation (systemic inflammatory response syndrome) associated with cardiac surgery often leads to a worse short-term and long-term outcome. Stress doses of hydrocortisone have been successfully used to improve outcome of CS. The interleukin (IL)-6 to IL-10 ratio is associated with outcome after trauma and major surgery. Objective:To evaluate immunologic effects (especially IL-6 to IL-10 ratio) of stress doses of hydrocortisone in a high-risk group of patients after cardiac surgery with cardiopulmonary bypass. Design:Prospective, randomized, double-blinded, placebo-controlled trial. Setting:Cardiovascular intensive care unit of a university hospital. Patients:High-risk patients (n = 36) undergoing CS. Intervention:Stress doses of hydrocortisone or placebo. Main Outcome Measures:IL-6 to IL-10 ratio and other markers of systemic inflammation at predefined time points; short-term clinical outcome. Results:The two study groups did not differ with regard to demographic data. The patients from the hydrocortisone group (n = 19) had significantly lower levels of IL-6 and higher levels of IL-10, resulting in an attenuated change in IL-6/IL-10 ratio (28.7 [6.4/128.7] vs. 292.8 [6.5/534.6] 4 hours after cardiopulmonary bypass; p < 0.001). Patients in the hydrocortisone group had a shorter duration of catecholamine support (1 [1/2] vs. 4 [2/4.5] days; p = 0.02), a shorter length of stay in the intensive care unit (2 [2/3] vs. 6 [4/8] days; p = 0.001), and a lower incidence of postoperative atrial fibrillation (26% vs. 59%; p = 0.04). Conclusions:Stress doses of hydrocortisone attenuate the evolution of IL-6/IL-10 ratio in patients with systemic inflammatory response syndrome after CS, which seems to be associated with an improved outcome. The immunologic effects of hydrocortisone may thus be both, inhibitory (IL-6) and permissive (IL-10), regarding the immune response.

Substantially altered expression pattern of cannabinoid receptor 2 and activated endocannabinoid system in patients with severe heart failure.

Animal studies suggest that the endocannabinoid system (ECS) plays a role in the regulation of myocardial contractility and in the pathogenesis of heart failure. The current study aimed to proof the existence of endocannabinoid receptors on human ventricular myocardium and to determine whether human chronic heart failure (CHF) is associated with changes in endocannabinoid receptor expression and distribution. Expression of cannabinoid receptor 1 (CB1) and cannabinoid receptor (CB2) on human heart was assessed by means of real-time PCR and immunohistochemistry. On healthy human left ventricular myocardium, mRNA transcripts of CB1 and CB2 receptors were expressed in an almost equal proportion. In patients with CHF, mRNA expression of CB1 receptors was shown to be downregulated 0.7-fold (0.7.+/-0.15, n=12, p<0.01), whereas expression of CB2 receptors was upregulated more than 11-fold (11.6+/-4.5; n=12; p<0.005). Corresponding results were obtained by immunohistochemistry. Blood levels of endocannabinoids were significantly elevated (anandamide 3.5-fold (p<0.001); 2-AG 7-fold (p=0.02)) in patients with CHF, as compared to healthy volunteers. Both CB1 and CB2 receptors are present on healthy human left ventricular myocardium in a balanced distribution. Patients suffering from CHF exhibit a shift of the CB1-CB2 receptor ratio towards expression of CB2 receptors combined with significantly elevated peripheral blood levels of endocannabinoids indicating an activation of the ECS. These results might open up new perspectives regarding the role of endocannabinoid signalling in CHF and its potential as a target for pharmacological modulation.

Sirolimus-Associated Infertility: Case Report and Literature Review of Possible Mechanisms

The mammalian‐target‐of‐rapamycin/mTOR‐inhibitor sirolimus as a component of the immunosuppressive strategy after solid organ transplantation is effective at preventing allograft rejection. However, recent reports indicate that sirolimus is associated with altered sex hormone levels and impaired sperm quality parameters.

Impact of polyclonal anti-thymocyte globulins on the expression of adhesion and inflammation molecules after ischemia–reperfusion injury

BACKGROUND Polyclonal anti-thymocyte globulins (ATGs) are immunosuppressive agents used for the treatment and prevention of acute organ rejection after transplantation. ATGs induce apoptosis and complement-mediated cell death in peripheral T-lymphocytes and have shown a reduction of leukocyte adhesion after ischemia-reperfusion (IRI). We analyzed the impact of different ATGs upon the expression of adhesion and inflammation molecules after IRI. MATERIALS AND METHODS The major arteries and veins of the extremities of cynomolgus monkeys were surgically isolated and flushed with Ringers lactate at 4 degrees C. After 60 min of ischemia the limbs were reperfused with matching human blood. ATGs were added to the blood 30 min prior to the reperfusion, forming four groups: Tecelac-ATG group (n=16), Fresenius(S)-ATG group (n=16), Thymoglobulin-ATG group (n=12) and a control group (n=16). Biopsies from muscular tissue were obtained after the experiments. The expression of adhesion (ICAM-1, VCAM, PECAM, CD11b, CD62E) and inflammation (IL-1, IL-6, TNF-alpha) molecules on endothelium, leukocytes, and reperfused tissue was analyzed by means of immunohistochemistry. RESULTS The expression of the studied adhesion molecules (ICAM-1, VCAM, PECAM, CD11b, and CD62E) was significantly increased in the control group when compared with the treated groups. The expression of IL-1, IL-6, and TNF-alpha was reduced in the ATG-groups in comparison to the control group. DISCUSSION Our results showed that ATGs caused a reduction of the expression of adhesion and inflammation molecules both in endothelium and reperfused tissue. The inhibition of the expression of molecules required for firm cellular adhesion, may contribute to decreasing cellular graft infiltration after post-ischemic reperfusion.

Altered myocardial expression of ghrelin and its receptor (GHSR-1a) in patients with severe heart failure

Ghrelin is a peptide hormone mainly produced by the stomach, which strongly stimulates the release of growth hormone (GH) via the GH secretagogue receptor 1a (GHSR-1a) located in the hypothalamus. It has been reported to exert performance-enhancing effects on myocardial function, and as both ghrelin and GHSR-1a are expressed in myocardial tissues, the ghrelin system may have a direct GH-independent impact on cardiac function. We intended to investigate the expression of ghrelin and its receptor GHSR-1a in different myocardial areas of patients with chronic heart failure (CHF) as compared to heart-healthy subjects to better define the role of the ghrelin signaling system in the networks regulating cardiac function and its potential as a target for diagnosis and/or treatment of CHF. Myocardium biopsies of 12 patients undergoing heart transplantation and suffering from CHF were obtained. Expression of both ghrelin and GHSR-1a was assessed by means of immunohistochemistry and real-time PCR. Expression of ghrelin was significantly decreased in CHF hearts both in atrium and ventricles in comparison to the control hearts (p<0.05). The expression of the GHS-1a receptor was significantly increased in the CHF biopsies as compared to controls (p<0.05). No significant differences were found between the anatomical areas studied. Expression of myocardial ghrelin and GHSR-1a is directly associated with myocardial function: CHF hearts exhibit an impaired ghrelin production which might reflect maladaptive processes and an - probably compensatory - increase in GHSR-1a expression. These findings may open up new perspectives regarding the potential of ghrelin signaling as a target for pharmacological modulation.

Association between vasopressor dependence and early outcome in patients after cardiac surgery

Arterial hypotension with vasopressor dependence is a major problem after cardiac surgery. We evaluated the early postoperative course of 1558 consecutive patients scheduled for cardiac surgery, and compared the outcome of patients with and without vasopressor dependence (defined as the need for > 0.1 μg.kg−1.h−1 noradrenaline for > 3 h in the face of normovolaemia). Vasopressor dependence was diagnosed in 424 patients (27%) and was associated with a higher incidence of postoperative renal failure (67 (15.7%) vs 7 (0.6%), respectively; p < 0.0001), a longer duration of ventilation (median IQR [range]) 14 (8–26 [6–39]) h vs 8 (5–11 [4–32]) h; p < 0.0001), a greater need for red cell transfusion (3 (1–5 [0–10]) units vs 1 (0–2 [0–4]) units; p < 0.001) and a longer length of stay in the ICU (4 (2–6 [2–9] days) vs 2 (1–3 [1–6] days; p < 0.001). Vasopressor dependence could be predicted from a combination of factors, including pre‐operative ejection fraction < 37%, cardiopulmonary bypass lasting > 94 min, and postoperative interleukin‐6 > 837 pg.ml−1.