Association Between Body Mass Index, Obesity, and Clinical Outcomes Following Coronary Artery Bypass Grafting in Brazil: An Analysis of One Year of Follow-up of BYPASS Registry Patients

OBJECTIVE

To investigate the association between body mass index (BMI), obesity, clinical outcomes, and mortality following coronary artery bypass grafting (CABG) in Brazil using a large sample with one year of follow-up from the Brazilian Registry of Cardiovascular Surgeries in Adults (or BYPASS) Registry database.

METHODS

A multicenter cohort-study enrolled 2,589 patients submitted to isolated CABG and divided them into normal weight (BMI 20.0-24.9 kg/m2), overweight (BMI 25.0-29.9 kg/m2), and obesity (BMI > 30.0 kg/m2) groups. Inpatient postoperative outcomes included the most frequently described complications and events. Collected post-discharge outcomes included rehospitalization and mortality rates within 30 days, six months, and one year of follow-up.

RESULTS

Sternal wound infections (SWI) rate was higher in obese compared to normal-weight patients (relative risk [RR]=5.89, 95% confidence interval [CI]=2.37-17.82; P=0.001). Rehospitalization rates in six months after discharge were higher in obesity and overweight groups than in normal weight group (χ=6.03, P=0.049); obese patients presented a 2.2-fold increase in the risk for rehospitalization within six months compared to normal-weight patients (RR=2.16, 95% CI=1.17-4.09; P=0.045). Postoperative complications and mortality rates did not differ among groups during time periods.

CONCLUSION

Obesity increased the risk for SWI, leading to higher rehospitalization rates and need for surgical interventions within six months following CABG. Age, female sex, and diabetes were associated with a higher risk of mortality. The obesity paradox remains controversial since BMI may not be sufficient to assess postoperative risk in light of more complex and dynamic evaluations of body composition and physical fitness.

Performance Evaluation of Geometrically Different Pediatric Arterial Cannulae in a Pediatric Cardiopulmonary Bypass Model

OBJECTIVE

To define a reference chart comparing pressure drop vs. flow generated by a set of arterial cannulae currently utilized in cardiopulmonary bypass conditions in pediatric surgery.

METHODS

Cannulae from two manufacturers were selected considering their design and outer and inner diameters. Cannula performance was evaluated in terms of pressure drop vs. flow during simulated cardiopulmonary bypass conditions. The experimental circuits consisted of a Jostra HL-20 roller pump, a Quadrox-i pediatric oxygenator (Maquet Cardiopulmonary AG, Rastatt, Germany), and a custom pediatric tubing set. The circuit was primed with lactated Ringer's solution only (first condition) and with human packed red blood cells added (second condition) to achieve a hematocrit of 30%. Cannula sizes 8 to 16 Fr were inserted into the cardiopulmonary bypass circuit with a "Y" connector. The flow was adjusted in 100 ml/min increments within typical flow ranges for each cannula. Pre-cannula and post-cannula pressures were measured to calculate the pressure drop.

RESULTS

Utilizing a pressure drop limit of 100 mmHg, our results suggest a recommended flow limit of 500, 900, 1400, 2600, and 3100 mL/min for Braile arterial cannulae sizes 8, 10, 12, 14, and 16 Fr, respectively. For Medtronic DLP arterial cannulae sizes 8, 10, 12, 14, and 16 Fr, the recommended flow limit is 600, 1100, 1700, 2700, and 3300 mL/min, respectively.

CONCLUSION

This study reinforces discrepancies in pressure drop between cannulae of the same diameter supplied by different manufacturers and the importance of independent translational research to evaluate components' performance.

Extubation in the Operating Room After Coronary Artery Bypass Graft Surgery Reduces Hospital Stay

OBJECTIVES

The aim of this analysis was to compare the effect of extubating in the operating room (OR) versus and the intensive care unit (ICU) among patients undergoing coronary artery bypass grafting (CABG).

DESIGN

A retrospective cohort analysis.

SETTING

Ten cardiac referral hospitals in Latin America; participants of the São Paulo Registry of Cardiovascular Surgery II (REPLICCAR II).

PARTICIPANTS

The database included a total of 4,015 patients who underwent primary and isolated CABG surgery and were ≥18 years old, of whom 205 patients were extubated in the OR.

INTERVENTIONS

The analysis was made after a propensity score matching (PSM) adjustment in the population sample of patients extubated in the OR and ICU by the following variables: sex, age, body mass index, smoking, type of surgery, chronic obstructive pulmonary disease, preoperative atrial fibrillation, cardiopulmonary bypass time, preoperative creatinine, and preoperative left ventricular ejection fraction.

MEASUREMENTS AND MAIN RESULTS

This study focused on the analysis of the ICU and hospital length of stay, need for reintubation, morbidity, and mortality. After PSM, 402 patients were analyzed. Both groups had similar baseline characteristics, such as age (p = 0.132), sex (p = 1.00), and estimated risk of prolonged ventilation (>24 hours, p = 0.168); however, the median ventilation time was significantly shorter in the group extubated in the OR compared to the ICU group (5.67 hours v 17.55 hours, p < 0.001). The group of patients extubated in the ICU had a longer postoperative stay (7.54 ± 3.40 days v 6.41 ± 2.91 days, p < 0.001) and longer total hospitalization time (11.49 ± 5.70 days v 10.36 ± 5.72, p = 0.013) compared to those extubated in the OR. The authors did not observe a significant difference in the need for reintubation, morbidity, or mortality rates among the evaluated groups.

CONCLUSIONS

In the REPLICCAR II database, extubation performed in the OR was associated with a reduced length of postoperative and total hospital stays compared to extubation in the ICU.

Financial Impact of Deep Sternal Wound Infections After Coronary Surgery: A Microcosting Analysis

INTRODUCTION

Deep sternal wound infections (DSWI) are so serious and costly that hospital services continue to strive to control and prevent these outcomes. Microcosting is the more accurate approach in economic healthcare evaluation, but there are no studies in this field applying this method to compare DSWI after isolated coronary artery bypass grafting (CABG). This study aims to evaluate the incremental risk-adjusted costs of DSWI on isolated CABG.

METHODS

This is a retrospective, single-center observational cohort study with a propensity score matching for infected and non-infected patients to compare incremental risk-adjusted costs between groups. Data to homogeneity sample was obtained from a multicentric database, REPLICCAR II, and additional sources of information about costs were achieved with the electronic hospital system (Si3). Inflation variation and dollar quotation in the study period were corrected using the General Market Price Index. Groups were compared using analysis of variance, and multiple linear regression was performed to evaluate the cost drivers related to the event.

RESULTS

As expected, infections were costly; deep infection increased the costs by 152% and mediastinitis by 188%. Groups differed among hospital stay, exams, medications, and multidisciplinary labor, and hospital stay costs were the most critical cost driver.

CONCLUSION

In summary, our results demonstrate the incremental costs of a detailed microcosting evaluation of infections on CABG patients in São Paulo, Brazil. Hospital stay was an important cost driver identified, demonstrating the importance of evaluating patients' characteristics and managing risks for a faster, safer, and more effective discharge.

Severe and Moderate Primary Graft Dysfunction in Adult Heart Recipients

INTRODUCTION

The aims of this study were to determine the incidence of severe and moderate primary graft dysfunction (PGD) in our center, to identify, retrospectively, donors' and recipients' risk factors for PGD development, and to evaluate the impact of PGD within 30 days after heart transplantation.

METHODS

Donors' and recipients' medical records of 64 consecutive adult cardiac transplantations performed between January 2016 and June 2017 were reviewed. The International Society for Heart and Lung Transplantation (ISHLT) criteria were used to diagnose moderate and severe PGD. Associations of risk factors for combined moderate/severe PGD were assessed with appropriate statistical analyses.

RESULTS

Sixty-four patients underwent heart transplantation in this period. Twelve recipients (18.7%) developed severe or moderate PGD. Development of PGD was associated with previous donor cardiopulmonary resuscitation and a history of prior heart surgery in the recipient (P=0.01 and P=0.02, respectively). The 30-day in hospital mortality was similar in both PGD and non-PGD patients.

CONCLUSION

The use of the ISHLT criteria for PGD is important to identify potential risk factor. The development of PGD did not affect short-term survival in our study. More studies should be done to better understand the pathophysiology of PGD.

Circulating miRNA-770-5p and miRNA-30d-5p as potential biomarkers in vasoplegic syndrome after on-pump coronary artery bypass surgery – PREVENT trial

Introduction

Vasoplegic syndrome (VS) is one of the most common unexpected complications following cardiothoracic surgery, approaching a 25% mortality rate. No standardized methods for diagnosing VS are available. A biomarker is a valuable tool in all fields of medicine, especially in cardiovascular disease when the patient has to undergo invasive surgery as on-pump CABG. MicroRNAs (miRNAs) have been studied and employed as biomarkers for numerous diseases, however, there are no studies regarding their expression in VS.

Purpose

To discover a new predictor of VS by comparing the miRNA profiles from patients who evolved to VS versus those who did not evolve after following Coronary artery bypass graft surgery (CABG).

Methods

A nested case-control study had an exploratory nature and involved an initial cohort of 87 patients who underwent on-pump CABG in elective or urgency procedures,considering the low surgical risk (STS score &lt;2%). For this analysis, we compared 30 patients, divided into two groups: patients who evolved VS (VASO group, n=15) and who did not evolve VS (NONVASO group, n=15) after surgery. To perform the miRNA profiling, the target prediction, and identify the putative targets of the dysregulated miRNAs, the whole blood samples were collected after anesthetic induction and before incision in the chest (Figure 1A).

Results

We identified among the 754 screened miRNAs, eight differentially circulating miRNAs in the whole blood of VASO versus NONVASO groups (Figure 1B). Six miRNAs were increased (hsa-miR-548c-3p, hsa-miR-30d-5p, hsa-miR8 199b-5p, hsa-miR-183-3p, hsa-miR-571, hsa-miR-383-5p) and two were decreased (hsa-miR-1236-3p, hsa-miR-770-5p) and hsa-miR-1236-3p was not statistically significant (Figure 1C). The ROC curves for each single miRNAs yielded the top 2 highest AUC values of 0.8333 and 0.8178 for hsa-miR-770-5p and hsa-miR-30d-5p, respectively. The combination of these two miRNAs yielded an AUC value of 0.9615 with 84.6% sensitivity and 91.67% specificity in distinguishing patients from VASO from NONVASO groups showed a superior diagnostic power to that of a single miRNA (Figure 2). Computational analyses identified as the top enriched pathway the “Apelin Liver Signaling Pathway” with 14 out of 26 molecules within the pathway (53,8%) containing the higher number of targets of the dysregulated miRNAs. There was no statistical difference in preoperative, postoperative, EuroSCORE II, and variables comparing both groups.

Conclusion(s)

We showed that miRNA-770-5p and miRNA-30d-5p could be employed as potential biomarkers of VS, a new strategy to VS diagnosis since miRNAs expression could distinguish patients who could and could not evolve the disease. The capability of predicting VS with high accuracy would drastically change the clinical management and patient's referral to cardiac surgery by helping in decision-making once the clinical score risks proved to be unable to predict VS in low-risk patients.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Fundação de Amparo a Pesquisa de São Paulo - FAPESP

Nonatherosclerotic Giant Right Coronary Artery Aneurysm

We present an unusual case of a 67-year-old woman with an incidental finding of a cardiac mass on a chest computed tomography. Coronary angiotomography confirmed the diagnosis of right coronary artery aneurysm, with 5.7×5.7 cm. The patient underwent aneurysm resection and coronary bypass surgery, with subsequent histologic study suggestive of arteritis sequelae. Giant coronary artery aneurysms have a high risk of complications and aneurysm exclusion must be beneficial. This is a rare condition that can also be part of a systemic inflammatory disease.

A benchmark in the isolated tricuspid valve surgery is necessary

Advances in surgical techniques, enabling correction of regurgitation, and preserving the tricuspid valve, are also factors that encourage early surgical indication and improve long-term outcomes.

Multivessel Woven Coronary Artery Disease

Woven coronary disease is a rare pathology with unknown etiology. Although initially considered benign, recent publications report myocardial ischemia caused by the affected vessel. Since most patients are asymptomatic, long-term follow-up to understand its behavior is mandatory. We report a multivessel woven disease case with documented ischemia that was submitted to coronary artery bypass grafting and remained asymptomatic for two years of follow-up.

Preoperative Neutrophil-Lymphocyte Ratio Can Predict Outcomes for Patients Undergoing Tetralogy of Fallot Repair

INTRODUCTION

Elevated neutrophil-lymphocyte ratio (NLR) has been associated with poorer outcomes in cyanotic patients undergoing single ventricle palliation. Little is known about this biomarker on patients with tetralogy of Fallot (TOF), the most common cyanotic congenital heart disease. Our objective is to study the impact of preoperative NLR on outcomes of TOF patients undergoing total repair.

METHODS

This retrospective study included 116 consecutive patients between January 2014 and December 2018. Preoperative NLR was measured from the last complete blood count test before the surgery. Using the cutoff value of 0.80, according to the receiver-operating characteristic (ROC) curve, the sample was divided into two groups (NLR < 0.80 and ≥ 0.80). The primary endpoint was hospital length of stay (LOS).

RESULTS

ROC curves showed that higher preoperative NLR was associated with longer hospital LOS, with an area under the curve of 0.801±0.040 (95% confidence interval 0.722 - 0.879; P<0.001). High preoperative NLR was also associated with long intensive care unit (ICU) LOS (P=0.035). Preoperative NLR predicted longer hospital LOS with a sensitivity of 63% and a specificity of 81.4%.

CONCLUSION

Higher preoperative NLR was associated with long ICU and hospital LOS in patients undergoing TOF repair.

Translation and Validation of the Boston Technical Performance Score in a Developing Country

Introduction

The Technical Performance Score (TPS) was developed and subsequently refined at the Boston Children's Hospital. Our objective was to translate and validate its application in a developing country.

Methods

The score was translated into the Portuguese language and approved by the TPS authors. Subsequently, we studied 1,030 surgeries from June 2018 to October 2020. TPS could not be assigned in 58 surgeries, and these were excluded. Surgical risk score was evaluated using Risk Adjustment in Congenital Heart Surgery (or RACHS-1). The impact of TPS on outcomes was studied using multivariable linear and logistic regression adjusting for important perioperative covariates.

Results

Median age and weight were 2.2 (interquartile range [IQR] = 0.5-13) years and 10.8 (IQR = 5.6-40) kilograms, respectively. In-hospital mortality was 6.58% (n=64), and postoperative complications occurred in 19.7% (n=192) of the cases. TPS was categorized as 1 in 359 cases (37%), 2 in 464 (47.7%), and 3 in 149 (15.3%). Multivariable analysis identified TPS class 3 as a predictor of longer hospital stay (coefficient: 6.6; standard error: 2.2; P=0.003), higher number of complications (odds ratio [OR]: 1.84; 95% confidence interval [CI]: 1.1-3; P=0.01), and higher mortality (OR: 3.2; 95% CI: 1.4-7; P=0.004).

Conclusion

TPS translated into the Portuguese language was validated and showed to be able to predict higher mortality, complication rate, and prolonged postoperative hospital stay in a high-volume Latin-American congenital heart surgery program. TPS is generalizable and can be used as an outcome assessment tool in resource diverse settings.

Total surgical correction of Lutembacher syndrome associated with partial anomalous connection of the pulmonary veins and tricuspid regurgitation

Lutembacher syndrome is characterized by the association of mitral stenosis and atrial septal defect (ASD), usually of the ostium secundum type. The association between superior vena cava-type ASD and partial anomalous pulmonary venous connection is unusual and there are few descriptions in the literature. We report this condition in a 24-year-old woman who was admitted to the hospital with a 1-year history of progressive dyspnea and describe the successful surgical repair following mitral commissurotomy and tunneling of the anomalous pulmonary veins to the left atrium, which determines the closure of the ASD and tricuspid repair.

Applicability of the Disruptions in Surgery Index in the Cardiovascular Management Scenarios - A Marker for Developing Functionally Efficient Teams

Introduction

To support the development of practices and guidelines that might help to reduce adverse events related to human factors, we aimed to study the response and perception by members of a cardiovascular surgery team of various error-driven or adverse features that might arise in the operating room (OR).

Methods

A previously validated Disruptions in Surgery Index (DiSI) questionnaire was completed by individuals working together in a cardiovascular surgical unit. Results were submitted to reliability analysis by calculating the Cronbach’s alpha coefficient. Non-parametric Kruskal-Wallis test and Dunn’s post-test were performed to estimate differences in perceptions of adverse events or outcomes between the groups (surgeons, nurses, anesthesiologists, and technicians). P<0.05 was considered statistically significant.

Results

Cronbach’s alpha reliability coefficients showed consistency within the recommended range for all disruption types assessed in DiSI: an individual’s skill (0.85), OR environment (0.88), communication (0.81), situational awareness (0.92), patient-related disruption (0.89), team cohesion (0.83), and organizational disruption (0.83). Nurses (27.4%) demonstrated significantly higher perception of disruptions than surgeons (25.4%), anesthetists (23.3%), and technicians (23.0%) (P=0.005). Study participants were more observant of their colleagues’ disruptive behaviors than their own (P=0.0001).

Conclusion

Our results revealed that there is a tendency among participants to hold a positive self-perception position. DiSI appears to be a reliable and useful tool to assess surgical disruptions in cardiovascular OR teams, identifying negative features that might imperil teamwork and safety in the OR. And human factors training interventions are available to develop team skills and improve safety and efficiency in the cardiovascular OR.

Initial experience with del Nido cardioplegia solution at a Pediatric and Congenital Cardiac Surgery Program in Brazil

OBJECTIVE

The aim of this study was to evaluate outcome measures between our standard multidose cardioplegia protocol and a del Nido cardioplegia protocol in congenital heart surgery patients.

METHODS

Retrospective single-center study including 250 consecutive patients that received del Nido cardioplegia (DN group) with a mandatory reperfusion period of 30% of cross clamp time and 250 patients that received a modified St. Thomas' solution (ST group). Groups were matched by age, weight, gender, and Risk Adjustment for Congenital Heart Surgery (RACHS-1) scores. Preoperative hematocrit and oxygen saturation were also recorded. Outcomes analyzed were the vasoactive inotropic score (VIS), lactate, ventilation time, ventricular dysfunction with low cardiac output syndrome (LCOS), intensive care unit (ICU) length of stay (LOS), hospital LOS, bypass and aortic cross-clamp times, and in-hospital mortality.

RESULTS

Both groups were comparable demographically. Statistically significant differences (p ⩽ 0.05) were noted for cardiac dysfunction with LCOS, hematocrit at end of surgery (p = 0.0038), VIS on ICU admission and at end of surgery (p = 0.0111), and ICU LOS (p = 0.00118) with patients in the DN group having more desirable values for those parameters. Other outcome measures did not reach statistical significance.

CONCLUSION

In our congenital cardiac surgery population, del Nido cardioplegia strategy was associated with less ventricular dysfunction with LCOS, a lower VIS and decreased ICU LOS compared with patients that received our standard myocardial protection using a modified St. Thomas' solution. Despite the limitation of this study, including its retrospective nature and cohort size, these data supported our transition to incorporate del Nido cardioplegia solution with a mandatory reperfusion period as the preferred myocardial protection method in our program.

Impact of COVID-19 Pandemic in a Pediatric and Congenital Cardiovascular Surgery Program in Brazil

Introduction:

The coronavirus disease 2019 (COVID-19) has negatively impacted healthcare services worldwide. We hypothesized that the pandemic would affect our case mix and mortality. Our objective was to study this impact.

Methods:

We retrospectively studied all patients who underwent congenital heart surgeries from March 21^st to August 21^st in 2019 and 2020 using the institutional electronic database. We compared demographic data, preoperative and postoperative length of stay (LOS), risk stratification using Risk Adjustment for Congenital Heart Surgery (RACHS) classification and outcomes in both periods.

Results:

We observed a 66.7% decrease in our surgical volume (285 × 95 patients). Patients operated in the pre-pandemic period were older (911.3 [174.8 - 5953.8] days-old) compared to the pandemic period (275 days-old; P<0.05). When the case mix was compared between periods, the percentage of neonatal surgery was increased in the pandemic era (8% × 21.1%; P<0.05), and the number of RACHS 1-2 surgeries decreased significantly (60.7 × 27.4%; P<0.05). Preoperative LOS was increased in the pandemic period (1.2 × 7 days; P=0.001). There was no significant increment in mortality (P=0.1). Two patients tested positive for COVID-19 in the postoperative period and both died.

Conclusion:

Our program observed a sudden decrease in surgical volume and a consequent increase in surgical complexity. There was a non-significant increment in mortality.

Increased number of ventricular septal rupture cases after acute myocardial infarction in 2020

INTRODUCTION

Ventricular septal rupture (VSR) is a serious mechanical complication after acute coronary syndrome and is related to high mortality. Even with advances in the management of acute myocardial infarction (AMI) such as reperfusion therapies, complication rates are still high. During quarantine, patients presenting mechanical complications after AMI have increased in our institution.

METHODS

From a retrospective database analysis in our institution between the years 2004 and 2020, we identified 37 cases of VSR after AMI. Four chronic cases were excluded from our analysis. The primary endpoint was to identify baseline characteristics that increased 30-day mortality.

RESULTS

Among 33 acute cases of VSR, 24 cases were submitted to surgery. The 30-day mortality of the operated patients was 45.8%. From 2004 to 2019 our average number of operations of VSR was 1.9 cases/year with an increase to 4 cases/year in 2020. Diabetes mellitus, age, cardiogenic shock, and use of intra-aortic balloon pump were associated with significantly increased mortality using logistic regression.

CONCLUSION

We reported an increased number of mechanical complication cases from April to September 2020, compared to our historical records. Despite therapeutic advances, mortality rates remain high. Although the number of cases is small to conclude that the pandemic was responsible for this augmentation, we believe that it is related to the decreased number of patients seeking medical assistance.

Evaluation method of training simulation on biological models for cardiovascular surgery residents

OBJECTIVES

The goal of this study was to describe and evaluate our simulation training program on biological models for the cardiovascular surgery residency program at our institution.

MATERIAL AND METHODS

Since 2016, with the purpose to develop better practical performance and evaluate the improvement of resident's surgical skills, a simulation training program was implemented, composed of some elemental procedures in cardiovascular surgery. It was established with one wet lab session weekly lasting 2 h, coached by two expert cardiovascular surgeons. Bovine and porcine hearts were used as biological models. At the end of the hands-on program, an objective assessment consisting of two practical modules was applied and performance was rated by way of a 5-point scale. In addition, to provide a subjective assessment, each resident filled out a questionnaire consisting of three items reviewing the overall quality of the workshops on a 10-point scale.

RESULTS

The objective evaluation applied at the end of the training program consisted of valve replacement and coronary artery bypass grafting (CABG) modules. The mean performance rating scores for the valve replacement module ranged from 4.2 to 4.79, and CABG, from 4.33 to 4.87. Regarding subjective assessment, all items evaluated, such as expert's didactics, simulation performance, and biological simulator fidelity, received high grades (above 9 on a 10-point scale).

CONCLUSIONS

Simulator training on biological models for cardiac surgery medical residents is a simple and effective learning method of surgical skills.

Anemia in Cardiac Surgery - Can Something Bad Get Worse?

INTRODUCTION

Anemia and blood transfusion are risk factors for morbidity/mortality in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). The objective of this study is to analyze the association of blood transfusion with morbidity/ mortality in patients undergoing coronary artery bypass grafting (CABG) under CPB in the state of São Paulo, Brazil.

METHODS

This is a retrospective analysis using the State of São Paulo Registry of Cardiovascular Surgery from November 2013 to August 2014. Blood transfusion was only considered during surgery or within six hours after surgery. Anemia was defined as hematocrit ≤ 37.5%. Patients < 18 years old were excluded. The sample was divided in four groups - Group I (851, no anemia), Group II (200, anemia without blood transfusion), Group III (181, no anemia and transfusion), and Group IV (258, anemia and transfusion).

RESULTS

A total of 1,490 patients were included; 639 (42.9%) were anemic and 439 (29.5%) underwent blood transfusion. Group II showed lower composite morbidity (odds ratio [OR] -0.05; confidence interval [CI] -0.27-0.17; P=0.81) than Group III (OR 0.41; CI 0.23-0.59; P=0.018) or Group IV (OR 0.54; CI 0.31- 0.77; P=0.016). Group III was at greater risk of mortality (OR 0.73; CI 0.43-1.03; P=0.02) than Group II, which was exposed only to anemia (OR -0.13; CI -0.55-0.29; P=0.75), or Group IV (OR 0.29; CI -0.13-0.71; P=0.539).

CONCLUSION

Anemia in patients undergoing CABG with CPB is bad, but blood transfusion can be worse, increasing at least 50% the risk for mortality and/or morbidity.

Impact of COVID-19 Pandemic in a Brazilian High-Volume Aortic Center

Introduction

The coronavirus disease 2019 (COVID-19) pandemic brought an unprecedented lack of control of what was to come. The intent of this document is to provide a balance of how much was ceased to be done for patients with aortic disease, to assess the mortality of these patients, and to show what happened to those who became COVID-19 positive during their hospitalization.

Methods

From April 1st to July 31st 2020, the worst period of the pandemic in São Paulo, Brazil, the Institute’s aortic surgical patients operated on were evaluated and those were compared with patients operated during the same period in 2019.

Results

In 2019, 88 surgeries were performed; most of them were elective (66 [75%]), 10 were urgent, and 12 were emergency surgeries. In 2020, during the COVID-19 pandemic, we operated on only 31 patients, being 74.2% non-elective surgeries (P<0,001). There was a higher mortality for patients operated on during the pandemic surge of COVID-19 (P<0,001), but it was not specifically related to infected patients.

Conclusion

The COVID-19 pandemic had an impact on surgical volume and outcome of patients with aortic disease, although it did not directly increase mortality.

The use of internal mammary vein in coronary artery surgery

Arterial revascularization, and in particular, left internal mammary artery (LIMA), has shown to improve survival of patients with coronary artery disease. Complete revascularization often requires the use of other grafts and saphenous vein graft is still the most common conduit used. Several other types of grafts have been utilized during revascularization, including the radial artery and gastroepiploic artery. It is recognized that its venous structure can change when submitted to long-term blood pressure regimen. We, herein, report left internal mammary vein (LIMV) utilized as a novel conduit for coronary artery revascularization, that was patent after 6 years. LIMV is an easy graft to harvest if the LIMA is dissected as a pedicle. The long-term patency of LIMV is unknown, but its usage could be suggested for elderly patients with peripheral vascular disease, when long graft patency is not required.

Pericardial-Peritoneal Window as an Alternative Treatment for Large and Recurrent Pericardial Effusion Post-Pericardiotomy

INTRODUCTION

The presence of mild to moderate pericardial effusion after cardiac surgery is common and oral medical therapy is usually able to treat it. Larger effusions are less frequent and surgical intervention is usually necessary. However, there are some rare cases of large effusions that are recurrent even after intervention and become challenging to treat.

METHODS

We describe the case of a patient submitted to coronary artery bypass grafting (CABG) without any intraoperative complications, who was regularly discharged from the hospital. She was referred to our emergency department twice after surgery with large pericardial effusion that was drained. Even after those two interventions and with adequate oral medication, the large effusion recurred.

RESULTS

During follow-up, the patient had her symptoms resolved, with no need for further hospital admission. Her echocardiograms after the last intervention showed no pericardial effusion. The present surgical technique demonstrated to be easy to perform, thus it should be considered as a treatment option for these rare cases of large and repetitive effusions, which do not respond to the traditional methods.

CONCLUSIONS

In challenging cases of recurrent and large pericardial effusions, the pericardial-peritoneal window is an alternative surgical technique that brings clinical improvement and diminishes the risk of cardiac tamponade.

Platelet Reactivity in Patients With Acute Coronary Syndromes Awaiting Surgical Revascularization

BACKGROUND

Dual antiplatelet therapy is recommended for patients with acute coronary syndromes (ACS). Approximately 10% to 15% of these patients will undergo coronary artery bypass graft (CABG) surgery for index events, and current guidelines recommend stopping clopidogrel at least 5 days before CABG. This waiting time has clinical and economic implications.

OBJECTIVES

This study aimed to evaluate if a platelet reactivity-based strategy is noninferior to standard of care for 24-h post-CABG bleeding.

METHODS

In this randomized, open label noninferiority trial, 190 patients admitted with ACS with indications for CABG and on aspirin and P2Y₁₂ receptor inhibitors, were assigned to either control group, P2Y₁₂ receptor inhibitor withdrawn 5 to 7 days before CABG, or intervention group, daily measurements of platelet reactivity by Multiplate analyzer (Roche Diagnostics GmbH, Vienna, Austria) with CABG planned the next working day after platelet reactivity normalization (pre-defined as ≥46 aggregation units).

RESULTS

Within the first 24 h of CABG, the median chest tube drainage was 350 ml (interquartile range [IQR]: 250 to 475 ml) and 350 ml (IQR: 255 to 500 ml) in the intervention and control groups, respectively (p for noninferiority <0.001). The median waiting period between the decision to undergo CABG and the procedure was 112 h (IQR: 66 to 142 h) and 136 h (IQR: 112 to 161 h) (p < 0.001), respectively. In the intention-to-treat analysis, a 6.4% decrease in the median in-hospital expenses was observed in the intervention group (p = 0.014), with 11.2% decrease in the analysis per protocol (p = 0.003).

CONCLUSIONS

A strategy based on platelet reactivity-guided is noninferior to the standard of care in patients with ACS awaiting CABG regarding peri-operative bleeding, significantly shortens the waiting time to CABG, and decreases hospital expenses. (Evaluation of Platelet Aggregability in the Release of CABG in Patients With ACS With DAPT; NCT02516267).

Treatment and Chest Reconstruction for Mediastinitis Following Sternotomy for Cardiac Surgery at the Heart Institute of the University of São Paulo Medical School

This study presents the method used for chest reconstruction and treatment of mediastinitis following cardiac surgery at the Heart Institute of the University of São Paulo Medical School. After infection control with antibiotic therapy associated with aggressive surgical debridement and negative pressure wound therapy, chest reconstruction is performed using flaps. The advantages and disadvantages of negative pressure wound therapy are discussed, as well as options for flap-based chest reconstruction according to the characteristics of the patient and sternum. Further studies are needed to provide evidence to support the decisions when facing this great challenge.

Brazilian Single-Center Experience with Aortic Root Replacement in 448 Patients: What Is the Best Technique?

Introduction

The objective of this study was to evaluate whether a surgery with the use of valved conduit is capable of leading to better immediate and late results than those obtained by the valve-sparing aortic root reconstruction technique.

Methods

Between January 2002 and June 2016, 448 patients underwent aortic root reconstruction. These were divided into three groups according to the technique used: 319 (71.2%) patients received mechanical valved conduits, 49 (10.9%) received biological valved conduits, and 80 (17.9%) underwent the valve-sparing aortic root reconstruction technique. The results were examined by univariate and multivariate analyses of Cox proportional hazards models with multiple logistic regression.

Results

The hospital mortality rate was 7.5%. The mortality rates were 8.2%, 12%, and 2.5% in the mechanical valved conduit, biological valved conduit, and aortic valve-sparing groups, respectively, with no significant difference between groups (P=0.1). Thromboembolic complications and reoperation-free survival were also similar (P=0.169 and P=0.688). However, valve-sparing aortic root replacement was superior in terms of long-term survival (P<0.001), hemorrhagic-free survival (P<0.001), and endocarditis-free survival (P=0.048). Multivariate analysis showed that the following aspects had an impact on mortality: age > 70 years (P<0.001; hazard ratio [HR] 1.05), preoperative acute kidney injury (P<0.0042; HR 2.9), diagnosis of dissection (P<0.01; HR 2.0), previous cardiac surgery (P<0.027; HR 2.3), associated coronary artery bypass grafting (P<0.038; HR 1.8), reoperation for postoperative tamponade (P<0.004; HR 2.2) and postoperative acute kidney injury (P<0.02; HR 3.35).

Conclusion

Valve-sparing technique seems to be the operation of choice, whenever possible, for aortic root reconstruction.

Heterotopic Heart Transplantation as a Left Ventricular Biological Assistance: a New Two-Stage Method Proposal

Since Barnard’s first heterotopic heart transplant in 1974, Copeland’s method has been the greatest contribution to heterotopic transplants but has the drawback of donor’s right ventricular atrophy. This new method proposes a modification in the anastomosis of the superior vena cava aiming to pre-serve donor’s right ventricular function by decompressing the pulmonary territory and reducing the pulmonary arterial pressure, as a biological ventricular assist device. Finally, a second intervention is proposed, where a “twist” is performed to place the donor’s heart in an orthotopic position after re-moval of the native heart. A pioneering research on this method received approval from the ethics committee of the Heart Institute of São Paulo. We believe that this method has the potential to im-prove quality of life in a selected group of patients.

Coronary Artery Bypass Graft During the COVID-19 Pandemic

Since the beginning of the coronavirus disease (COVID-19) pandemic, in March 2020, the number of people infected with COVID-19 worldwide increases continuously. Brazil is being followed with great concern in the international media, as it can, very soon, be the epicenter of the pandemic. Initial surgical data suggest that patients who acquire COVID-19 in the perioperative period are prone to a higher morbidity and mortality, however, evidence in cardiac surgery is still scarce.

This article aims to aggregate to the growing evidence suggesting that perioperative infection with severe acute respiratory syndrome coronavirus 2 contributes to a more morbid evolution of the case.

Geometric reconstruction of a left ventricular aneurysm with coronary artery bypass graft

Left ventricular aneurysm is a late mechanical complication of untreated acute myocardial infarction. It has become relatively rare since the development of percutaneous cardiac intervention.  Most aneurysms are located at the anterior ventricular wall, and are caused by total occlusion of the left anterior descending artery. Usually, the anterior and apical walls initially become akinetic; this can sometimes evolve into dyskinesia. Thrombus formation is a common finding, since the apical contractility is impaired. This tutorial illustrates the challenging technical aspects of a large thrombus removal, along with the geometric reconstruction of the left ventricular aneurysm and coronary bypass surgery.

Impact of Vacuum-Assisted Venous Drainage on Forward Flow in Simulated Pediatric Cardiopulmonary Bypass Circuits Utilizing a Centrifugal Arterial Pump Head

Objective

To analyze the impact of vacuum-assisted venous drainage (VAVD) on arterial pump flow in a simulated pediatric cardiopulmonary bypass circuit utilizing a centrifugal pump (CP) with an external arterial filter.

Methods

The simulation circuit consisted of a Quadrox-I Pediatric oxygenator, a Rotaflow CP (Maquet Cardiopulmonary AG, Rastatt, Germany), and a custom pediatric tubing set primed with Lactated Ringer's solution and packed red blood cells. Venous line pressure, reservoir pressure, and arterial flow were measured with VAVD turned off to record baseline values. Four other conditions were tested with progressively higher vacuum pressures (-20, -40, -60, and -80 mmHg) applied to the baseline cardiotomy pressure. An arterial filter was placed into the circuit and arterial flow was measured with the purge line in both open and closed positions. These trials were repeated at set arterial flow rates of 1500, 2000, and 2500 mL/min.

Results

The use of progressively higher vacuum caused a reduction in effective arterial flow from 1490±0.00 to 590±0.00, from 2020±0.01 to 1220±0.00, and from 2490±0.0 to 1830±0.01 mL/min. Effective forward flow decreased with increased levels of VAVD.

Conclusion

The use of VAVD reduces arterial flow when a CP is used as the main arterial pump. The reduction in the forward arterial flow increases as the vacuum level increases. The loss of forward flow is further reduced when the arterial filter purge line is kept in the recommended open position.

An independent flow probe is essential to monitor pump flow during cardiopulmonary bypass.

Late clinical outcomes of myocardial hybrid revascularization versus coronary artery bypass grafting for complex triple-vessel disease: Long-term follow-up of the randomized MERGING clinical trial

OBJECTIVES

This article aimed to compare the outcomes after hybrid revascularization with conventional coronary artery bypass grafting (CABG) surgery.

BACKGROUND

The concept of hybrid coronary revascularization combines the advantages of CABG and percutaneous coronary intervention to improve the treatment of patients with complex multivessel disease.

METHODS

The Myocardial hybrid revascularization versus coronary artERy bypass GraftING for complex triple-vessel disease-MERGING study is a pilot randomized trial that allocated 60 patients with complex triple-vessel disease to treatment with hybrid revascularization or conventional CABG (2:1 ratio). The primary outcome was the composite of all-cause death, myocardial infarction, stroke, or unplanned repeat revascularization at 2 years.

RESULTS

Clinical and anatomical characteristics were similar between groups. After a mean follow-up of 802 ± 500 days, the primary endpoint rate was 19.3% in the hybrid arm and 5.9% in the CABG arm (p = NS). The incidence of unplanned revascularization increased over time in both groups, reaching 14.5 versus 5.9% in the hybrid and in the CABG groups, respectively (p = .4). Of note, in the hybrid group, there were no reinterventions driven by the occurrence of stent restenosis.

CONCLUSIONS

Hybrid myocardial was feasible but associated with increasing rates of major adverse cardiovascular events during 2 years of clinical follow-up, while the control group treated with conventional surgery presented with low rates of complications during the same period. In conclusion, before more definitive data arise, hybrid revascularization should be applied with careful attention in practice, following a selective case-by-case indication.

Quadricuspid Aortic Valve: Three Cases Report and Literature Review

Quadricuspid aortic valve (QAV) is a rare cardiac malformation. Many cases are incidentally diagnosed in aortic surgeries or autopsies and it usually appears as an isolated anomaly. The most widely classification used is the one by Hurwitz and Roberts^[1], which divides 7 alphabetical subtypes based on the cusps size. The aim of this report is to describe three different anatomic presentations of this rare aortic valve anomaly.

Early and Long-Term Outcomes of Surgical Treatment of Ebstein's Anomaly

OBJECTIVE

This study aimed to evaluate Ebstein's anomaly surgical correction and its early and long-term outcomes.

METHODS

A retrospective analysis of 62 consecutive patients who underwent surgical repair of Ebstein's anomaly in our institution from January 2000 to July 2016. The following long-term outcomes were evaluated: survival, reoperations, tricuspid regurgitation, and postoperative right ventricular dysfunction.

RESULTS

Valve repair was performed in 46 (74.2%) patients - 12 of them using the Da Silva cone reconstruction; tricuspid valve replacement was performed in 11 (17.7%) patients; univentricular palliation in one (1.6%) patient; and the one and a half ventricle repair in four (6.5%) patients. The patients' mean age at the time of surgery was 20.5±14.9 years, and 46.8% of them were male. The mean follow-up time was 8.8±6 years. The 30-day mortality rate was 8.06% and the one and 10-year survival rates were 91.9% both. Eleven (17.7%) of the 62 patients required late reoperation due to tricuspid regurgitation, in an average time of 7.1±4.9 years after the first procedure.

CONCLUSION

In our experience, the long-term results of the surgical treatment of Ebstein's anomaly demonstrate an acceptable survival rate and a low incidence of reinterventions.

Early outcomes of transcatheter tricuspid valve-in-valve implantation: a case series

OBJECTIVES

In this study, we sought to evaluate early outcomes of transcatheter valve-in-valve implantation in patients with a degenerated bioprosthesis in the tricuspid position.

METHODS

We used a prospective study, which included patients with a degenerated bioprosthesis in the tricuspid position who were considered high-risk by our heart team and who underwent a valve-in-valve implantation. The procedures were performed via transjugular venous access and were done with the patient under general anaesthesia with transoesophageal echocardiographic and fluoroscopic guidance. Perioperative data were analysed, and the patients were followed prospectively.

RESULTS

Seven patients were included. The baseline diagnoses were 3 patients with Ebstein's anomaly, 1 patient with tetralogy of Fallot, 1 patient with neonatal endocarditis, 1 patient with ventricular septal defect with a double tricuspid lesion and 1 patient with rheumatic mitral and tricuspid valve who underwent a combined transapical mitral and transjugular tricuspid valve-in-valve implantation. The mean age was 33 ± 10.8 years and 57.1% of the patients were men. The mean number of previous thoracotomies was 3 ± 2 (range 1-5) procedures. The mean follow-up was 1.24 years. The implant was successful in all cases, and there was no need for conversion to open surgery. There were no deaths during the study period, and all patients are currently in the New York Heart Association functional class I/II. There was a statistically significant difference when the mean transvalvular gradients preimplantation and postimplantation were compared (P < 0.001).

CONCLUSIONS

Percutaneous tricuspid valve implantation should be considered a safe and effective therapy and stands as a viable, reliable alternative for the treatment of a degenerated bioprosthesis in high-surgical-risk/inoperable patients.

Coronary Artery Bypass Surgery in Brazil: Analysis of the National Reality Through the BYPASS Registry

Introduction

Coronary artery bypass grafting (CABG) is the most frequently performed heart surgery in Brazil. Recent international guidelines recommend that national societies establish a database on the practice and results of CABG. In anticipation of the recommendation, the BYPASS Registry was introduced in 2015.

Objective

To analyze the profile, risk factors and outcomes of patients undergoing CABG in Brazil, as well as to examine the predominant surgical strategy, based on the data included in the BYPASS Registry.

Methods

A cross-sectional study of 2292 patients undergoing CABG surgery and cataloged in the BYPASS Registry up to November 2018. Demographic data, clinical presentation, operative variables, and postoperative hospital outcomes were analyzed.

Results

Patients referred to CABG in Brazil are predominantly male (71%), with prior myocardial infarction in 41.1% of cases, diabetes in 42.5%, and ejection fraction lower than 40% in 9.7%. The Heart Team indicated surgery in 32.9% of the cases. Most of the patients underwent cardiopulmonary bypass (87%), and cardioplegia was the strategy of myocardial protection chosen in 95.2% of the cases. The left internal thoracic artery was used as a graft in 91% of the cases; the right internal thoracic artery, in 5.6%; and the radial artery in 1.1%. The saphenous vein graft was used in 84.1% of the patients, being the only graft employed in 7.7% of the patients. The median number of coronary vessels treated was 3. Operative mortality was 2.8%, and the incidence of cerebrovascular accident was 1.2%.

Conclusion

CABG data in Brazil provided by the BYPASS Registry analysis are representative of our national reality and practice. This database constitutes an important reference for indications and comparisons of therapeutic procedures, as well as to propose subsequent models to improve patient safety and the quality of surgical practice in the country.

Perioperative Management of the Diabetic Patient Referred to Cardiac Surgery

Currently there is a progressive increase in the prevalence of diabetes in a referred for cardiovascular surgery. Benefits of glycemic management (< 180 mg/dL) in diabetic patients compared to patients without diabetes in perioperative cardiac surgery. The purpose of this study is to present recommendations based on international evidence and adapted to our clinical practice for the perioperative management of hyperglycemia in adult patients with and without diabetes undergoing cardiovascular surgery. This update is based on the latest current literature derived from articles and guidelines regarding perioperative management of diabetic patients to cardiovascular surgery.

Use of 3D Printing in Preoperative Planning and Training for Aortic Endovascular Repair and Aortic Valve Disease

Introduction

Three-dimensional (3D) printing has become an affordable tool for assisting heart surgeons in the aorta endovascular field, both in surgical planning, education and training of residents and students. This technique permits the construction of physical prototypes from conventional medical images by converting the anatomical information into computer aided design (CAD) files.

Objective

To present the 3D printing feature on developing prototypes leading to improved aortic endovascular surgical planning, as well as transcatheter aortic valve implantation, and mainly enabling training of the surgical procedure to be performed on patient's specific condition.

Methods

Six 3D printed real scale prototypes were built representing different aortic diseases, taken from real patients, to simulate the correction of the disease with endoprosthesis deployment.

Results

In the hybrid room, the 3D prototypes were examined under fluoroscopy, making it possible to obtain images that clearly delimited the walls of the aorta and its details. The endovascular simulation was then able to be performed, by correctly positioning the endoprosthesis, followed by its deployment.

Conclusion

The 3D printing allowed the construction of aortic diseases realistic prototypes, offering a 3D view from the two-dimensional image of computed tomography (CT) angiography, allowing better surgical planning and surgeon training in the specific case beforehand.

Behavior of Ultrasensitive C-Reactive Protein in Myocardial Revascularization with and without Cardiopulmonary Bypass

Objective

To analyze the inflammation resulting from myocardial revascularization techniques with and without cardiopulmonary bypass, based on ultrasensitive C-reactive protein (US-CRP) behavior.

Methods

A prospective non-randomized clinical study with 136 patients was performed. Sixty-nine patients were enrolled for Group 1 (on-pump coronary artery bypass - ONCAB) and 67 patients were assigned to Group 2 (off-pump coronary artery bypass - OPCAB). All study participants had blood samples collected for analysis of glucose, triglycerides, creatinine, total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL) and creatinephosphokinase (CPK) in the preoperative period. The samples of creatinephosphokinase MB (CKMB), troponin I (TnI) and US-CRP were collected in the preoperative period and at 6, 12, 24, 36, 48 and 72 hours after surgery. We also analyzed the preoperative biological variables of each patient (age, smoking, diabetes mellitus, left coronary trunk lesion, body mass index, previous myocardial infarction, myocardial fibrosis). All angiographically documented patients with >70% proximal multiarterial stenosis and ischemia, documented by stress test or classification of stable angina (class II or III), according to the Canadian Cardiovascular Society, were included. Reoperations, combined surgeries, recent acute myocardial infarction, recent inflammatory disease, deep venous thrombosis or recent pulmonary thromboembolism, acute kidney injury or chronic kidney injury were not included.

Results

Correlation values between the US-CRP curve and the ONCAB group, the treatment effect and the analyzed biological variables did not present expressive results. Laboratory variables were evaluated and did not correlate with the applied treatment (P>0.05).

Conclusion

The changes in the US-CRP at each moment evaluated from the postoperative period did not show any significance in relation to the surgical technique applied.

Thrombocytopenia After Transcatheter Valve-in-Valve Implantation: Prognostic Marker or Mere Finding?

Objective

To analyze the behavior of platelets after transcatheter valve-in-valve implantation for the treatment of degenerated bioprosthesis and how they correlate with adverse events upon follow-up.

Methods

Retrospective analysis of 28 patients who received a valve-in-valve implant, 5 in aortic, 18 in mitral and 5 in tricuspid positions. Data were compared with 74 patients submitted to conventional redo valvular replacements during the same period, and both groups' platelet curves were analyzed. Statistical analysis was conducted using the IBM SPSS Statistics(r) 20 for Windows.

Results

All patients in the valve-in-valve group developed thrombocytopenia, 25% presenting mild (<150.000/µL), 54% moderate (<100.000/µL) and 21% severe (<50.000/µL) thrombocytopenia. The platelet nadir was on the 4^th postoperative day for aortic ViV, 2^nd for mitral and 3^rd for tricuspid patients, with the majority of patients recovering regular platelet count. However, the aortic subgroup comparison between valve-in-valve and conventional surgery showed a statistically significant difference from the 7^th day onwards, where valve-in-valve patients had more severe and longer lasting thrombocytopenia. This, however, did not translate into a higher postoperative risk. In our study population, postoperative thrombocytopenia did not correlate with greater occurrence of adverse outcomes and only normal preoperative platelet count could significantly predict a postoperative drop >50%.

Conclusion

Although thrombocytopenia is an extremely common finding after valve-in-valve procedures, the degree of platelet count drop did not correlate with greater incidence of postoperative adverse outcomes in our study population.

Ten-Year Follow-Up of Off-Pump and On-Pump Multivessel Coronary Artery Bypass Grafting: MASS III

It was a randomized trial, and 308 patients undergoing revascularization were randomly assigned: 155 to off-pump coronary artery bypass (OPCAB) and 153 to on-pump coronary artery bypass (ONCAB). End points were freedom from death, myocardial infarction, revascularization, and cerebrovascular accidents. The rates for 10-year, event-free survival for ONCAB versus OPCAB were 69.6% and 64%, (hazard ratio [HR]: 0.88; 95% confidence interval [CI] 0.86-1.02; P = .41), respectively. Adjusted Cox proportional hazard ratio was similar (HR: 0.92; 95% CI 0.61-1.38, P = .68). A difference occurred between the duration of OPCAB and ONCAB, respectively (4.9 ± 1.5 vs 6.6 ± 1.1 h, P < .001). Statistical differences occurred between OPCAB and ONCAB in the length of intensive care unit (ICU) stay (20 ± 2.5 vs 48 ± 10 hours, P < .001), time to extubation (5.5 ± 4.2 vs 10.2 ± 3.5 hours, P < .001), hospital stay (6.7 ± 1.4 vs 9.2 ± 1.3 days, P < .001), higher incidence of atrial fibrillation (AF; 33 vs 5 patients, P < .001), and blood requirements (46 vs 64 patients, P < .001). Grafts per patient was higher in ONCAB (3.15 vs 2.55 grafts, P < .001). No difference existed between the groups in primary composite end points at 10-year follow-up. Although OPCAB surgery was related to a lower number of grafts and higher incidence of AF, it had no effects related to long-term outcomes.

Functional Performance of Different Venous Limb Options in Simulated Neonatal/Pediatric Cardiopulmonary Bypass Circuits

OBJECTIVE

Hemodilution is a concern in cardiopulmonary bypass (CPB). Using a smaller dual tubing rather than a single larger inner diameter (ID) tubing in the venous limb to decrease prime volume has been a standard practice. The purpose of this study is to evaluate these tubing options.

METHODS

Four different CPB circuits primed with blood (hematocrit 30%) were investigated. Two setups were used with two circuits for each one. In Setup I, a neonatal oxygenator was connected to dual 3/16" ID venous limbs (Circuit A) or to a single 1/4" ID venous limb (Circuit B); and in Setup II, a pediatric oxygenator was connected to dual 1/4" ID venous limbs (Circuit C) or a single 3/8" ID venous limb (Circuit D). Trials were conducted at arterial flow rates of 500 ml/min up to 1500 ml/min (Setup I) and up to 3000 ml/min (Setup II), at 36°C and 28°C.

RESULTS

Circuit B exhibited a higher venous flow rate than Circuit A, and Circuit D exhibited a higher venous flow rate than Circuit C, at both temperatures. Flow resistance was significantly higher in Circuits A and C than in Circuits B (P<0.001) and D (P<0.001), respectively.

CONCLUSION

A single 1/4" venous limb is better than dual 3/16" venous limbs at all flow rates, up to 1500 ml/min. Moreover, a single 3/8" venous limb is better than dual 1/4" venous limbs, up to 3000 ml/min. Our findings strongly suggest a revision of perfusion practice to include single venous limb circuits for CPB.

Rational Use of Mechanical Circulatory Support as a Bridge to Pediatric and Congenital Heart Transplantation

Introduction

Donor shortage and organ allocation is the main problem in pediatric heart transplant. Mechanical circulatory support is known to increase waiting list survival, but it is not routinely used in pediatric programs in Latin America.

Methods

All patients listed for heart transplant and supported by a mechanical circulatory support between January 2012 and March 2016 were included in this retrospective single-center study. The endpoints were mechanical circulatory support time, complications, heart transplant survival and discharge from the hospital.

Results

Twenty-nine patients from our waiting list were assessed. Twelve (45%) patients were initially supported by extracorporeal membrane oxygenation (ECMO) and a centrifugal pump was implanted in 17 (55%) patients. Five patients initially supported by ECMO were bridged to another device. One was bridged to a centrifugal pump and four were bridged to Berlin Heart Excor®. Among the 29 supported patients, 18 (62%) managed to have a heart transplant. Thirty-day survival period after heart transplant was 56% (10 patients). Median support duration was 12 days (interquartile range [IQR] 4 - 26 days) per run and the waiting time for heart transplant was 9.5 days (IQR 2.5-25 days). Acute kidney injury was identified as a mortality predictor (OR=22.6 [CI=1.04-494.6]; P=0.04).

Conclusion

Mechanical circulatory support was able to bridge most INTERMACS 1 and 2 pediatric patients to transplant with an acceptable complication rate. Acute renal failure increased mortality after mechanical circulatory support in our experience.

Predictive performance of six mortality risk scores and the development of a novel model in a prospective cohort of patients undergoing valve surgery secondary to rheumatic fever

BACKGROUND

Mortality prediction after cardiac procedures is an essential tool in clinical decision making. Although rheumatic cardiac disease remains a major cause of heart surgery in the world no previous study validated risk scores in a sample exclusively with this condition.

OBJECTIVES

Develop a novel predictive model focused on mortality prediction among patients undergoing cardiac surgery secondary to rheumatic valve conditions.

METHODS

We conducted prospective consecutive all-comers patients with rheumatic heart disease (RHD) referred for surgical treatment of valve disease between May 2010 and July of 2015. Risk scores for hospital mortality were calculated using the 2000 Bernstein-Parsonnet, EuroSCORE II, InsCor, AmblerSCORE, GuaragnaSCORE, and the New York SCORE. In addition, we developed the rheumatic heart valve surgery score (RheSCORE).

RESULTS

A total of 2,919 RHD patients underwent heart valve surgery. After evaluating 13 different models, the top performing areas under the curve were achieved using Random Forest (0.982) and Neural Network (0.952). Most influential predictors across all models included left atrium size, high creatinine values, a tricuspid procedure, reoperation and pulmonary hypertension. Areas under the curve for previously developed scores were all below the performance for the RheSCORE model: 2000 Bernstein-Parsonnet (0.876), EuroSCORE II (0.857), InsCor (0.835), Ambler (0.831), Guaragna (0.816) and the New York score (0.834). A web application is presented where researchers and providers can calculate predicted mortality based on the RheSCORE.

CONCLUSIONS

The RheSCORE model outperformed pre-existing scores in a sample of patients with rheumatic cardiac disease.

Pre-validation Study of the Brazilian Version of the Disruptions in Surgery Index (DiSI) as a Safety Tool in Cardiothoracic Surgery

Introduction

Most risk stratification scores used in surgery do not include external and non-technical factors as predictors of morbidity and mortality.

Objective

The present study aimed to translate and adapt transculturally the Brazilian version of the Disruptions in Surgery Index (DiSI) questionnaire, which was developed to capture the self-perception of each member of the surgical team regarding the disruptions that may contribute to error and obstruction of safe surgical flow.

Methods

A universalist approach was adopted to evaluate the conceptual equivalence of items and semantics, which included the following stages: (1) translation of the questionnaire into Portuguese; (2) back translation into English; (3) panel of experts to draft the preliminary version; and (4) pre-test for evaluation of verbal comprehension by the target population of 43 professionals working in cardiothoracic surgery.

Results

The questionnaire was translated into Portuguese and its final version with 29 items obtained 89.6% approval from the panel of experts. The target population evaluated all items as easy to understand. The mean overall clarity and verbal comprehension observed in the pre-test reached 4.48 ± 0.16 out of the maximum value of 5 on the psychometric Likert scale.

Conclusion

Based on the methodology used, the experts' analysis and the results of the pre-test, it is concluded that the essential stages of translation and cross-cultural adaptation of DiSI to the Portuguese language were satisfactorily fulfilled in this study.

Do We Need to Personalize Renal Function Assessment in the Stratification of Patients Undergoing Cardiac Surgery?

Background

Renal dysfunction is an independent predictor of morbidity and mortality in cardiac surgery. For a better assessment of renal function, calculation of creatinine clearance (CC) may be necessary.

Objective

To objectively evaluate whether CC is a better risk predictor than serum creatinine (SC) in patients undergoing cardiac surgery.

Methods

Analysis of 3,285 patients registered in a prospective, consecutive and mandatory manner in the Sao Paulo Registry of Cardiovascular Surgery (REPLICCAR) between November 2013 and January 2015. Values of SC, CC (Cockcroft-Gault) and EuroSCORE II were obtained. Association analysis of SC and CC with morbidity and mortality was performed by calibration and discrimination tests. Independent multivariate models with SC and CC were generated by multiple logistic regression to predict morbidity and mortality following cardiac surgery.

Results

Despite the association between SC and mortality, it did not calibrate properly the risk groups. There was an association between CC and mortality with good calibration of risk groups. In mortality risk prediction, SC was uncalibrated with values > 1.35 mg /dL (p < 0.001). The ROC curve showed that CC is better than SC in predicting both morbidity and mortality risk. In the multivariate model without CC, SC was the only predictor of morbidity, whereas in the model without SC, CC was not only a mortality predictor, but also the only morbidity predictor.

Conclusion

Compared with SC, CC is a better parameter of renal function in risk stratification of patients undergoing cardiac surgery.

The Brazilian Registry of Adult Patient Undergoing Cardiovascular Surgery, the BYPASS Project: Results of the First 1,722 Patients

Objective

To report the early results of the BYPASS project - the Brazilian registrY of adult Patient undergoing cArdiovaScular Surgery - a national, observational, prospective, and longitudinal follow-up registry, aiming to chart a profile of patients undergoing cardiovascular surgery in Brazil, assessing the data harvested from the initial 1,722 patients.

Methods

Data collection involved institutions throughout the whole country, comprising 17 centers in 4 regions: Southeast (8), Northeast (5), South (3), and Center-West (1). The study population consists of patients over 18 years of age, and the types of operations recorded were: coronary artery bypass graft (CABG), mitral valve, aortic valve (either conventional or transcatheter), surgical correction of atrial fibrillation, cardiac transplantation, mechanical circulatory support and congenital heart diseases in adults.

Results

83.1% of patients came from the public health system (SUS), 9.6% from the supplemental (private insurance) healthcare systems; and 7.3% from private (out-of -pocket) clinic. Male patients comprised 66%, 30% were diabetics, 46% had dyslipidemia, 28% previously sustained a myocardial infarction, and 9.4% underwent prior cardiovascular surgery. Patients underwent coronary artery bypass surgery were 54.1% and 31.5% to valve surgery, either isolated or combined. The overall postoperative mortality up to the 7^th postoperative day was 4%; for CABG was 2.6%, and for valve operations, 4.4%.

Conclusion

This first report outlines the consecution of the Brazilian surgical cardiac database, intended to serve primarily as a tool for providing information for clinical improvement and patient safety and constitute a basis for production of research protocols.

Cerebral hemodynamics with intra-aortic balloon pump: business as usual?

OBJECTIVE

Intra-aortic balloon pump (IABP) is commonly used as mechanical support after cardiac surgery or cardiac shock. Although its benefits for cardiac function have been well documented, its effects on cerebral circulation are still controversial. We hypothesized that transfer function analysis (TFA) and continuous estimates of dynamic cerebral autoregulation (CA) provide consistent results in the assessment of cerebral autoregulation in patients with IABP.

APPROACH

Continuous recordings of blood pressure (BP, intra-arterial line), end-tidal CO₂, heart rate and cerebral blood flow velocity (CBFV, transcranial Doppler) were obtained (i) 5 min with IABP ratio 1:3, (ii) 5 min, starting 1 min with the IABP-ON, and continuing for another 4 min without pump assistance (IABP-OFF). Autoregulation index (ARI) was estimated from the CBFV response to a step change in BP derived by TFA and as a function of time using an autoregressive moving-average model during removal of the device (ARI _t ). Critical closing pressure and resistance area-product were also obtained.

MAIN RESULTS

ARI with IABP-ON (4.3  ±  1.2) were not different from corresponding values at IABP-OFF (4.7  ±  1.4, p  =  0.42). Removal of the balloon had no effect on ARI _t , CBFV, BP, cerebral critical closing pressure or resistance area-product.

SIGNIFICANCE

IABP does not disturb cerebral hemodynamics. TFA and continuous estimates of dynamic CA can be used to assess cerebral hemodynamics in patients with IABP. These findings have important implications for the design of studies of critically ill patients requiring the use of different invasive support devices.