Three-Dimensional Printing: is it useful for Cardiac Surgery?

Introduction

The medical use of three-dimensional (3-D) images has been a topic in the literature since 1988, but 95% of papers on 3-D printing were published in the last six years. The increase in publications is the result of advances in 3-D printing methods, as well as of the increasing availability of these machines in different hospitals. This paper sought to review the literature on 3-D printing and to discuss thoughtful ideas regarding benefits and challenges to its incorporation into cardiothoracic surgeons’ routines.

Methods

A comprehensive and systematic search of the literature was performed in PubMed and included material published as of March 2020.

Results

Using this search strategy, 9,253 publications on 3-D printing and 497 on “heart” 3-D printing were retrieved.

Conclusion

3-D printed models are already helping surgeons to plan their surgeries, helping patients and their families to understand complex anatomy, helping fellows and residents to practice surgery, even for rare cases, and helping nurses and other health care staff to better understand some conditions, such as heart diseases.

In vivo evaluation of Vivere bovine pericardium valvular bioprosthesis with a new anti-calcifying treatment

The objective of this study was to evaluate the effect of chemical treatment with glutamic acid to avoid calcification of biological cardiac valves. The bovine pericardium (BP) tissues were fixed with 0.5% glutaraldehyde (BP/GA), followed by treatment with glutamic acid (BP/GA + Glu) for neutralization of the free aldehyde groups. Microscopic analysis showed that the wavy structure of collagen fibrils was preserved, but changes in elastin's integrity occurred. However, the treatment did not promote undesirable changes in the thermal and mechanical properties of the modified BPs. These samples were systematically studied in rat subcutaneous tissue: control (BP/GA) and anticalcificant (BP/GA + Glu). After 60 days, both groups induced similar inflammatory reactions. In terms of calcification, BP/GA + Glu remained more stable with a lower index (3.1 ± 0.2 μg Ca²⁺ /mg dry tissue), whereas for BP/GA it was 5.7 ± 1.3 μg Ca²⁺ /mg dry tissue. Bioprostheses made from BP/GA + Glu were implanted in the pulmonary position in sheep, and in vivo echocardiographic analyses revealed maintenance of valvar function after 180 days, with low gradients and minimal valve insufficiency. The explanted tissues of the BP/GA + Glu group had a lower average calcium content 3.8 ± 3.0 μg Ca²⁺ /mg dry tissue. The results indicated high anticalcification efficiency of BP/GA + Glu in both subcutaneous implant in rats and in the experimental sheep model, which is an advantage that should encourage the industrial application of these materials for the manufacture of bioprostheses.

Main Considerations of Cardiogenic Shock and Its Predictors: Systematic Review

The mortality rate of post-infarction cardiogenic shock (CS) was 80.0-90.0%. Recent studies show a significant reduction of hospital mortality to approximately 50.0%. CS is defined as systemic tissue hypoperfusion resulting from systolic and/or diastolic heart dysfunction, the main cause of which is acute myocardial infarction (AMI). The main predictors are biological markers such as troponin, CKMB and lactate. A systematic literature review and meta-analysis is performed in order to present and correlate the main literary findings on CS and its evolution with possible changes in biomarkers such as troponin, lactate and CKMB. After criteria of literary search with the use of the mesh terms: cardiogenic shock; acute myocardial infarction; biomarkers; troponin; CKMB; lactate; clinical trials and use of the bouleanos "and" between the mesh terms and "or" among the historical findings. In the main databases such as Pubmed, Medline, Bireme, EBSCO, Scielo, etc., a total of 96 papers that were submitted to the eligibility analysis were collated and, after that, 41 studies were selected, following the rules of systematic review - PRISMA (Transparent reporting of systematic reviews and meta-analyzes-http://www.prisma-statement.org/). Some risk factors for its development in AMI are advanced age, female gender, anterior wall infarction, diabetes mellitus, systemic arterial hypertension, previous history of infarction and angina. The CS associated with AMI depends on its extent and its complications, being the main ones: mitral regurgitation, rupture of the interventricular septum and rupture of the free wall of the left ventricule. The diagnosis is based on the clinical manifestations, such as mental confusion, oliguria, hypotension, tachycardia, fine pulse, sweating, and cold extremities; in hemodynamic aspects: systolic blood pressure was < 90.0 mm Hg or 30 mm Hg below baseline, pulmonary capillary pressure was > 18.0 mm Hg and cardiac index was < 2.2 L/min/m². Laboratory and imaging exams should be requested to evaluate the possible etiology of CS, its systemic repercussions and comorbidities. The treatment aims at the rapid reestablishment of the blood flow in the affected artery, to improve the patient's prognosis. The biomarkers dosage in the daily clinical practice of the different cardiological centers can facilitate the diagnosis and the conduction of the dubious cases and the best evaluation of the degree of myocardial suffering after CS.

Surgical Ablation of Atrial Fibrillation Using Energy Sources

Surgical ablation, concomitant with other operations, is an option for treatment in patients with chronic atrial fibrillation. The aim of this study is to present a literature review on surgical ablation of atrial fibrillation in patients undergoing cardiac surgery, considering energy sources and return to sinus rhythm. A comprehensive survey was performed in the literature on surgical ablation of atrial fibrillation considering energy sources, sample size, study type, outcome (early and late), and return to sinus rhythm. Analyzing studies with immediate results (n=5), the percentage of return to sinus rhythm ranged from 73% to 96%, while those with long-term results (n=20) (from 12 months on) ranged from 62% to 97.7%. In both of them, there was subsequent clinical improvement of patients who underwent ablation, regardless of the energy source used. Surgical ablation of atrial fibrillation is essential for the treatment of this arrhythmia. With current technology, it may be minimally invasive, making it mandatory to perform a procedure in an attempt to revert to sinus rhythm in patients requiring heart surgery.

In-Vitro Evaluation of a New Inferior Vena Cava Filter—The Stent-Filter

Inferior vena cava filters are indicated for the prevention of pulmonary embolism when anticoagulation using heparin has failed or is contraindicated. The aim of this study was to assess in an in-vitro setting the efficiency of a new inferior vena cava filter to intercept emboli. The new filter, stent-filter, was inserted into a pulsating flow circuit. Then thrombi were produced by introducing sheep's blood into silicon tubes with 3 mm diameter. A combination of 9% saline solution with 40% glycerol was used as the isosmotic fluid in the circuit. A total of 150 thrombi were introduced into the circuit in 3 stages of 50 events each. The flow rate in each of the 3 stages was altered; initially a rate of 1.0 liter per minute was chosen, and after this, it was increased to 1.5 liters and finally 2.0 liters per minute. The percentage of interceptions was used for statistical analysis. In the in-vitro experiment, the filter captured 94%, 90%, and 92% of the thrombi at flow rates of 1.0, 1.5, and 2.0 liters per second, respectively. In conclusion the new filter was effective in the interception of the thrombi when it was evaluated in in-vitro conditions.

Risk factors for mortality of patients undergoing coronary artery bypass graft surgery

Introduction

Coronary artery bypass grafting is a safe procedure performed worldwide with low rates of mortality and morbidity in general population.

Objective

To investigate risk factors for mortality of patients undergoing coronary artery bypass grafting coronary artery bypass grafting surgery.

Methods

A total of 1,628 consecutive patients undergoing on-pump coronary artery bypass grafting were retrospectively studied from December 1999 to February 2012. Data analysis involved paired Student t test, Mann-Whitney test and Fisher’s exact test for the categorical data. Logistic regression, Odds Ratio and 95%CI were used for definition of risk factors for mortality.

Results

Of a total of 1,628 patients undergoing on-pump coronary artery bypass grafting, 141 (8.7%) died. The following risk factors for mortality were identified after logistic regression: dialysis (OR=7.61; 95%CI 3.58-16.20), neurologic dysfunction type I (OR=4.42; 95%CI 2.48-7.81), use of IABP (OR=3.38; 95%CI 1.98-5.79), cardiopulmonary bypass time (OR=3.09; 95%CI 2.04-4.68), serum creatinine on admission and peak values > 0.4mg/dL (OR=2.67; 95%CI 1.79-4.00), age > 65 years (OR=2.31; 95%CI 1.55-3.44), and time between hospital admission and and surgical procedure (OR=1.53; 95%CI 1.03-2.27).

Conclusion

Dialysis, type I neurologic dysfunction, use of IABP, cardiopulmonary bypass time (> 115 minutes), serum creatinine on admission and peak values>0.4mg/dL, age > 65 years and time between hospital admission and surgical procedure were considered as risk factors for mortality in patients undergoing on-pump coronary artery bypass grafting surgery.

Endnote Web tutorial for BJCVS/RBCCV

At present, many useful tools for reference management are available for use. They can be either off-line softwares or accessible Websites to all users in the internet. Their target is to facilitate the production of scientific text. But, to accomplish that, the featured bibliographic style should be effectively inserted, and the program has to be free. Here in this tutorial, we present Endnote Web^®, a bibliographic reference management program comprising these two requirements: it contains the Brazilian Journal of Cardiovascular Surgery reference format and its use is free for charge after sign-in in IP registered terminal in Web of Science^®.

Modes of induced cardiac arrest: hyperkalemia and hypocalcemia--literature review

The entry of sodium and calcium play a key effect on myocyte subjected to cardiac arrest by hyperkalemia. They cause cell swelling, acidosis, consumption of adenosine triphosphate and trigger programmed cell death. Cardiac arrest caused by hypocalcemia maintains intracellular adenosine triphosphate levels, improves diastolic performance and reduces oxygen consumption, which can be translated into better protection to myocyte injury induced by cardiac arrest.

Implantation of transcatheter aortic valve prosthesis through the ascending aorta concomitant with coronary artery bypass grafting without cardiopulmonary bypass

Introdution

The transcatheter aortic valve implantation in the treatment of high-risk symptomatic aortic stenosis has increased the number of implants every year. The learning curve for transcatheter aortic valve implantation has improved since the last 12 years, allowing access alternatives.

Objective

The aim of this study is to approach the implantation of transcatheter aortic valve through transaortic via associated with off-pump cardiopulmonary bypass surgery in a 67-year-old man, with chronic obstructive pulmonary disease, arterial hypertension and kidney transplant.

Methods

Off-pump coronary artery bypass surgery was performed and the valve in the aortic position was released successfully.

Results

There were no complications in the intraoperative and postoperative period. Gradient reduction, effective orifice increasing of the prosthesis and absence of valvular regurgitation after implantation were observed by transesophageal echocardiography.

Conclusion

Procedural success demonstrates that implantation of transcatheter aortic valve through the ascending aorta associated with coronary artery bypass surgery without CPB is a new option for these patients.

Comparison of the solution of histidine-tryptophan-alfacetoglutarate with histidine-tryptophan-glutamate as cardioplegic agents in isolated rat hearts: an immunohistochemical study

Introduction

Cardiac arrest during heart surgery is a common procedure and allows the surgeon to perform surgical procedures in an environment free of blood and movement. Using a model of isolated rat heart, the authors compare a new cardioplegic solution containing histidine-tryptophan-glutamate (group 2) with the histidine-tryptophan-alphacetoglutarate (group 1) routinely used by some cardiac surgeons.

Objective

To assess caspase, IL-8 and KI-67 in isolated rat hearts using immunohistochemistry.

Methods

20 Wistar male rats were anesthetized and heparinized. The chest was opened, cardioctomy was performed and 40 ml/kg of the appropriate cardioplegic solution was infused. The hearts were kept for 2 hours at 4ºC in the same solution, and thereafter, placed in the Langendorff apparatus for 30 minutes with Ringer-Locke solution. Immunohistochemistry analysis of caspase, IL-8, and KI-67 were performed.

Results

The concentration of caspase was lower in group 2 and Ki-67 was higher in group 2, both P<0.05. There was no statistical difference between the values of IL-8 between the groups.

Conclusion

Histidine-tryptophan-glutamate solution was better than histidine-tryptophan-alphacetoglutarate solution because it reduced caspase (apoptosis), increased KI-67 (cell proliferation), and showed no difference in IL-8 levels compared to group 1. This suggests that the histidine-tryptophan-glutamate solution was more efficient than the histidine-tryptophan-alphacetoglutarate for the preservation of hearts of rat cardiomyocytes.

Comparison of fractal dimension and Shannon entropy in myocytes from rats treated with histidine-tryptophan-glutamate and histidine-tryptophan cetoglutarate

INTRODUCTION

Solutions that cause elective cardiac arrest are constantly evolving, but the ideal compound has not yet been found. The authors compare a new cardioplegic solution with histidine-tryptophan-glutamate (Group 2) and other one with histidine-tryptophan-cetoglutarate (Group 1) in a model of isolated rat heart.

OBJECTIVE

To quantify the fractal dimension and Shannon entropy in rat myocytes subjected to cardioplegia solution using histidine-tryptophan with glutamate in an experimental model, considering the caspase markers, IL-8 and KI-67.

METHODS

Twenty male Wistar rats were anesthetized and heparinized. The chest was opened, the heart was withdrawn and 40 ml/kg of cardioplegia (with histidine-tryptophan-cetoglutarate or histidine-tryptophan-glutamate solution) was infused. The hearts were kept for 2 hours at 4ºC in the same solution, and thereafter placed in the Langendorff apparatus for 30 min with Ringer-Locke solution. Analyzes were performed for immunohistochemical caspase, IL-8 and KI-67.

RESULTS

The fractal dimension and Shannon entropy were not different between groups histidine-tryptophan-glutamate and histidine-tryptophan-acetoglutarate.

CONCLUSION

The amount of information measured by Shannon entropy and the distribution thereof (given by fractal dimension) of the slices treated with histidine-tryptophan-cetoglutarate and histidine-tryptophan-glutamate were not different, showing that the histidine-tryptophan-glutamate solution is as good as histidine-tryptophan-acetoglutarate to preserve myocytes in isolated rat heart.

Evolution of weight and height of children with congenital heart disease undergoing surgical treatment

OBJECTIVE

To evaluate the height and weight development of children with congenital heart disease undergoing surgery with the goal of determining when they reach the threshold of normal development and whether there are differences between patients with developmental pattern below the level of normality preoperatively (z-score<-2 for the analyzed parameter) in comparison to the total group of cardiac patients.

METHODS

We prospectively followed up 27 children undergoing operation into five time periods: preoperatively and at four subsequent outpatient appointments: 1st month, 3rd month, 6th month and 12th month after hospital discharge. The anthropometric parameters used were median z-score (MZ), weight (WAZ), height (HAZ), subscapular skinfold (SSFAZ), upper arm circumference (UAC) and triceps skinfold (TSFAZ). The evolution assessment of the parameters was performed by analysis of variance and comparison with the general normal population from unpaired t test, both in the total group of cardiac patients, and in subgroups with preoperative parameters below the normal level (Zm<-2).

RESULTS

In the total group there was no significant evolution of MZ of all parameters. WAZ was statistically lower than the normal population until the 1st month of follow-up (P=0.028); HAZ only preoperatively (P=0.044), SSFAZ in the first month (P=0.015) and at 12th month (P=0.038), UAC and TSFAZ were always statistically equal to the general population. In patients whose development was below the level of normality, there were important variation of WAZ (P=0.002), HAZ (P=0.001) and UAC (P=0.031) after the operation, and the WAZ was lower than the normal population until the 3rd month (P=0.015); HAZ and UAC, until the first month (P=0.024 and P=0.039 respectively), SSFAZ, up to the 12th month (P=0.005), the TSFAZ only preoperatively (P=0.011).

CONCLUSION

The operation promoted the return to normalcy for those with heart disease in general within up to three months, but for the group of patients below normal developmental pattern of the return occurred within 12 months.

The calcium paradox - what should we have to fear?

The calcium paradox was first mentioned in 1966 by Zimmerman et al. Thereafter gained great interest from the scientific community due to the fact of the absence of calcium ions in heart muscle cells produce damage similar to ischemia-reperfusion. Although not all known mechanisms involved in cellular injury in the calcium paradox intercellular connection maintained only by nexus seems to have a key role in cellular fragmentation. The addition of small concentrations of calcium, calcium channel blockers, and hyponatraemia hypothermia are important to prevent any cellular damage during reperfusion solutions with physiological concentration of calcium.

Skeletonized versus pedicled internal thoracic artery and risk of sternal wound infection after coronary bypass surgery: meta-analysis and meta-regression of 4817 patients

It is suggested that the internal thoracic artery (ITA) harvesting technique influences the incidence of sternal wound infection (SWI) after coronary artery bypass graft (CABG). To determine if there is any real difference between skeletonized vs pedicled ITA, we performed a meta-analysis to determine if there is any real difference between these two established techniques in terms of SWI. We performed a systematic review using MEDLINE, EMBASE, CENTRAL/CCTR, SciELO, LILACS, Google Scholar and reference lists of relevant articles to search for studies that compared the incidence of SWI after CABG between skeletonized vs pedicled ITA until June 2012. The principal summary measures were odds ratio (OR) with 95% confidence interval (CI) and P values (statistically significant when <0.05). The ORs were combined across studies using the weighted DerSimonian-Laird random effects model and weighted Mantel-Haenszel fixed effects. Meta-analysis, sensitivity analysis and meta-regression were completed using the software Comprehensive Meta-Analysis version 2 (Biostat, Inc., Englewood, NJ, USA). Twenty-two studies involving 4817 patients (2424 skeletonized; 2393 pedicled) met the eligibility criteria. There was no evidence for important heterogeneity of effects among the studies. The overall OR (95% CI) of SWI showed a statistically significant difference in favour of skeletonized ITA (fixed effect model: OR 0.443, 95% CI 0.323-0.608, P < 0.001; random effect model: OR 0.443, 95% CI 0.323-0.608, P < 0.001). In the sensitivity analysis, the difference in favour of skeletonized ITA was also observed in subgroups such as diabetic, bilateral ITA and diabetic with bilateral ITA; we also observed that there was a difference in the type of study, since non-randomized studies together demonstrated the benefit of skeletonized ITA in comparison with pedicled ITA, but the randomized studies together did not show this difference (although close to statistical significance and with the tendency to favour the skeletonized group). In meta-regression, we observed a statistically significant coefficient for SWI and proportion of diabetic patients (coefficient -0.02, 95% CI -0.03 to -0.01, P = 0.016). In conclusion, skeletonized ITA appears to reduce the incidence of postoperative SWI in comparison with pedicled ITA after CABG, with this effect being modulated by the presence of diabetes.

Hybrid treatment for correction of pseudoaneurysm after surgical treatment of aortic coarctation

The need for a new surgical procedure for correction of postoperative pseudoaneurysm of aortic coarctation makes the procedure especially challenging for the surgeon.ta abstract.

Associated factors with survivals in patients undergoing orthotopic heart transplant using retrograde blood microcardioplegia

BACKGROUND

Several techniques and cardioplegic solutions have been used for heart preservation during transplant procedures. Unfortunately, there is a lack of ideal method for myocardial preservation in the clinical practice. The use of retrograde cardioplegia provides continuous infusion of cardioplegic solution during the graft implantation. This strategy may provide better initial recovery of the graft. The objective of this study is to describe the experience of a single center where all patients received the same solution for organ preservation and were subjected to continuous retrograde blood microcardioplegia during implantation of the graft and to evaluate factors associated to early and late mortality with this technique.

METHODS

This is a retrospective, observational and descriptive study of a single center.

RESULTS

During the study period were performed 35 heart transplants. Fifteen (42.9%) patients were in cardiogenic shock. The probability of survival was 74.8±7.8%, 60.4±11.3% and 15.1±13.4% at 1 year, 5 years and 10 years of follow-up, respectively. The median survival time was 96.6 months.

CONCLUSION

The use of myocardial protection with retrograde cardioplegic solution may reduce the risks associated morbidity due to cold ischemia time during the heart transplant, and we suggest that this benefit may be even greater in cases of cold ischemia time longer ensuring protection to the myocardium.

Assistance model for patients with asthma in the primary care

To create a program structured for the control and prevention towards asthma worsening, it is necessary to settle down actions of regionalization, planning and management. Currently, the Ministerial orders allow each municipality district to cope their needs with local initiatives, based on the search of the health indicators with University partnerships. Taking into account this context, it is feasible the implantation of an effective model through organized demand of attendance flow and physical structure, besides the withdrawal of medications and professional training. To describe the modus operandi situation currently in the Primary Health Care Units regarding these patients' reception, diagnosis, and follow-up, as well as the current situation according to the professional profile and sector. To introduce an assistance model for reception, of these patients in these primary care units. This is a bibliographical review based on the specialized literature such as scientific papers selected through the search on the SciELO and Bireme databases, from Medline and Lilacs data sources. A Committee was set up by members from the Health and Service , the Medical School, and scientific societies for discussion and planning.

Novo modelo de endoprótese traqueal autoexpansível de fabricação nacional: estudo experimental em coelhos

Objetivamos testar um novo modelo de endoprótese traqueal autoexpansível para que esse possa ser futuramente disponibilizado para o uso clínico. As endopróteses de nitinol revestidas de poliuretano foram alocadas no terço médio da traqueia de 25 coelhos da raça Nova Zelândia sob laringoscopia direta. Após um período de observação médio de 26 dias, avaliou-se a migração da prótese, grau de dilatação, incorporação, aderência, formação de tecido de granulação, presença de infiltrado inflamatório, envolvimento parietal e revestimento epitelial. Os resultados demonstraram completa expansibilidade radial, pouca aderência à mucosa traqueal e baixa incorporação tecidual, assim como alta taxas de formação de granulomas e de migração. Esse novo modelo demonstrou ser biocompatível e teve comportamento semelhante ao de outras próteses disponíveis no mercado.

Coronary artery bypass graft surgery after acute myocardial infarction caused by thrombosis of coronary aneurysm

The morphology of coronary aneurysm sets a predisposing factor to thrombus formation. However, the blood stasis caused by the change in flow may not be enough to cause thromboembolic events.

Perioperative serum troponin I levels are associated with higher risk for atrial fibrillation in patients undergoing coronary artery bypass graft surgery

Atrial fibrillation (AF) remains a frequent complication after coronary artery bypass graft surgery (CABG). We evaluate the association of AF occurrence and serum cardiac troponin I (cTnI) levels in the early postoperative period after CABG. Between April 2009 and January 2010, 95 consecutive patients with sinus rhythm who underwent CABG were evaluated. The patients were divided into two groups according to their postoperative rhythms: sinus rhythm group (SR) and AF group (AF). Demographic, clinical variables, and troponin I were evaluated at the pre- and postoperative times. There were no clinical or demographic differences between the two groups. The postoperative troponin I in the SR group was lower than that in the AF group (0.66 ± 1.62 vs. 2.07 ± 5.01 ng/ml; P = 0.029). Using the receiver operating characteristic curves was found as the best cut-off value to predict AF occurrence at the value of 0.901 ng/ml. Using this value of cTnI, a sensitivity of 60% and a specificity of 87% for AF onset prediction were observed. The cTnI serum levels at the postoperative period after CABG were higher in patients who subsequently developed AF. The cut-off value of 0.901 ng/ml is useful for prediction and preventive therapeutic actions.

In vitro properties and performance of glutaraldehyde-crosslinked bovine pericardial bioprostheses treated with glutamic acid

Calcification is one of the major causes of failure of heart valve bioprostheses (HVBs) derived from glutaraldehyde (GA)-processed bovine pericardium (BP) or porcine aortic valves. New crosslinking reagent procedures are still far from giving satisfactory results, and this is the main reason why GA is still the reagent of choice for the fixation of native tissue intended for HVB manufacture. Nevertheless, two new findings with respect to GA processing may significantly improve HVB performance postimplantation: the finding that increasing concentrations of GA result in a decrease in calcification; the blocking of free aldehyde usually by nucleophyles or the treatment of processed material at low pH. This work investigates the in vitro properties of BP fixed with GA followed by the treatment with glutamic acid under alkaline conditions in order to prepare BP materials with lower calcification potential postimplantation. In comparison to conventional processing, except for the tensile strength that was slightly lower, elongation and toughness were higher than the accepted values. No significant differences were observed in the performance indexes (mean pressure gradient, mean effective area, regurgitant fraction, performance and efficiency indexes) with wear resistance over 150 × 10⁶ cycles. These results indicate that the processing of BP described in this work may be of potential use in the manufacture of HVBs.

A bovine pericardium rigid prosthesis for left ventricle restoration: 12 years of follow-up

BACKGROUND

Myocardial infarction might result in dilated left ventricle and numerous techniques have been described to restore the original left ventricle shape and identify tools for late survival assessment. The aim of this study is to compare our experience with a modified Dor procedure using a rigid prosthesis to the septal anterior ventricular exclusion procedure (SAVE) for left ventricle restoration. The EuroScore index for prediction of late follow up survival was evaluated.

METHODS

We evaluated 80 patients who underwent left ventricle restoration between 1999 to 2007 and eight patients were excluded with incomplete data. A modified Dor procedure with rigid prosthesis (MD group) was performed on 53 patients and 19 underwent the septal anterior ventricular exclusion procedure (SAVE group). The patients were classified according their left ventricle shape as type I, II or III. Kaplan-Meier and Cox proportional hazard ratio regressions analysis were performed to assess survival after both techniques and expected surgical mortality using EuroScore index ranking after 12 years of follow up.

RESULTS

The operative mortality was comparable in both groups ranked by EuroScore index. The groups were comparable for all clinical data, except the MD group had more patients using intra-aortic balloon pumps before surgery, (5.7% vs. 0; P<0.01). Kaplan Meier analysis by left ventricle shape showed comparable survival for all patients, with slightly higher survival for type I. Kaplan Meier analysis of all death showed equivalent survival curves for both techniques after 12 years of follow up (71.5 ± 12.3 vs. 46.6 ± 20.5 years; P=0.08). Kaplan Meier analysis of EuroScore index for all patients showed a difference between the three ranked categories, i.e., 0 to 10%, 11 to 49% and higher than 50% expected surgical mortality after 12 years of follow up (70.9 ± 16.2 vs. 67.5 ± 12.7 vs. 53.0 ± 15.5; P=0.003).

CONCLUSION

The MD procedure showed consistent ejection fraction improvements after long term follow up. Survival was comparable for all ventricular types and for the MD and SAVE procedures. The EuroScore index is a useful index for late survival assessment of ventricular restoration techniques.

Surgical treatment of chronic type A aortic dissection in patients undergoing coronary artery bypass grafting

Surgical treatment of aortic dissection is a challenge for the cardiac surgeon, especially in patients undergoing cardiac operations. Our objective in this case report is to demonstrate how we treat the chronic type A aortic dissection in patients revascularized using percutaneous arterial and venous cannulae.

Effect of walking on pressure variations that occur at the interface between elastic stockings and the skin

The aim of this work was to dynamically study pressure variations exerted by elastic compression stockings during walking. While study participants walked, the pressure variations at the interface between elastic stockings and the skin were measured dynamically. Three healthy individuals wearing 10/20 and 20/30 elastic compression stockings manufactured by Sigvaris((R)) (Jundiai, São Paulo-Brazil) were requested to walk along a course for ten times at a constant speed. For every event, an apparatus specifically developed for the study and programmed to take readings at half-second intervals was used to measure the pressure exerted by the elastic stockings. The pressure exerted by the 10/20 stockings varied between 5 and 32 mmHg and for the 20/30 stockings it varied from 10 to 52 mmHg. Elastic stockings with larger pressures generate larger pressure variations during muscle activity (P-value < 0.001). In conclusion, muscle movements during walking cause the pressure exerted by elastic stockings on the leg to vary; thus, the pressure is not constant but has peaks and troughs according to the type of muscle movement and the gradient of the stockings.

The article of the future

Technological advances and the Internet have contributed to the increased disclosure and updating of knowledge and science. Scientific papers are considered the best form of disclosure of information and have been undergoing many changes, not on their way of development, but on the structure of publication. The Future paper, a name for this new structure, uses hypermediatic resources, allowing a quick, easy and organized access to these items online. The exchange of information, comments and criticisms can be performed in real time, providing agility in science disclosure. The trend for the future of documents, both from professionals or enterprises, is the "cloud computing", in which all documents will be developed and updated with the use of various equipments: computer, palm, netbook, ipad, without need to have the software installed on your computer, requiring only an Internet connection.