Fifth "Jatene Lecture on Surgical Innovation": Innovation in Congenital Heart Surgery: Contributions From South America.

We present the fifth "Jatene Lecture on Surgical Innovation" on Innovation in Congenital Heart Surgery, given at the Eighth Scientific Meeting of the World Society for Pediatric and Congenital Heart Surgery and Eighth World Congress of Pediatric Cardiology and Cardiac Surgery in Washington DC in 2023. We highlight what surgical innovation is and how innovation was accomplished in cardiac surgery and particularly in congenital heart surgery. A brief history of the development of congenital heart surgery across the world is summarized and we finally illustrate the South American contributions to congenital heart surgery, acknowledging the great innovations of Adib Jatene and Guillermo Kreutzer to our field.

Ischemic preconditioning does not prevent placental dysfunction induced by fetal cardiac bypass.

BACKGROUND: Remote ischemic preconditioning (rIPC) has been applied to attenuate tissue injury. We tested the hypothesis that rIPC applied to fetal lambs undergoing cardiac bypass (CB) reduces fetal systemic inflammation and placental dysfunction. METHODS: Eighteen fetal lambs were divided into three groups: sham, CB control, and CB rIPC. CB rIPC fetuses had a hindlimb tourniquet applied to occlude blood flow for four cycles of a 5-min period, followed by a 2-min reperfusion period. Both study groups underwent 30 min of normothermic CB. Fetal inflammatory markers, gas exchange, and placental and fetal lung morphological changes were assessed. RESULTS: The CB rIPC group achieved higher bypass flow rates (p < .001). After CB start, both study groups developed significant decreases in PaO2 , mixed acidosis, and increased lactate levels (p < .0004). No significant differences in tissular edema were observed on fetal lungs and placenta (p > .391). Expression of Toll-like receptor 4 and intercellular adhesion molecule-1 in the placenta and fetal lungs did not differ among the three groups, as well as with vascular cell adhesion molecule-1 (VCAM-1) of fetal lungs (p > .225). Placental VCAM-1 expression was lower in the rIPC group (p < .05). Fetal interleukin-1 (IL-1) and thromboxane A2 (TXA2) levels were lower at 60 min post-CB in the CB rIPC group (p < .05). There were no significant differences in tumor necrosis factor-α, prostaglandin E2, IL-6, and IL-10 plasma levels of the three groups at 60-min post-bypass (p > .133). CONCLUSION: Although rIPC allowed increased blood flow during fetal CB and decreased IL-1 and TXA2 levels and placental VCAM-1, it did not prevent placental dysfunction in fetal lambs undergoing CB.

Neutrophil-Lymphocyte Ratio in Congenital Heart Surgery: What Is Known and What Is New?

Operative mortality after repair of congenital heart disease has improved dramatically over the past few decades. Nevertheless, there is always room for the additional mitigation of complications and mortality. Being able to anticipate adverse outcomes is clearly important, especially when using low-cost and easily accessible resources. The neutrophil-lymphocyte ratio (NLR) is defined as the ratio of the absolute neutrophil to lymphocyte count, which can be easily measured using a regular white blood cell count. Recently, preoperative NLR has been shown to be a predictor of outcomes in patients undergoing congenital heart surgery. Although it presented promising results, there are still many gaps to be filled like the normal value for children, the ideal cutoff value to predict adverse outcomes, the wide variation and its correlation with other biomarkers, and if it is a modifiable risk factor. The aim of this review is to understand the prognostic value of preoperative NLR as a biomarker predictor of outcomes in patients undergoing congenital heart surgery based on previous clinical studies and to propose future directions in order to solve the above-mentioned questions.

COVID-19 pandemic implications in paediatric and congenital heart surgery in Brazil.

INTRODUCTION: The Coronavirus Disease 2019 (COVID-19) pandemic negatively impacted global healthcare. Consequences in Pediatric and Congenital Heart Surgery programmes and mortality of congenital heart patients infected with severe acute respiratory syndrome coronavirus-2 (SARS-Cov-2) is still to be determined. OBJECTIVE: To study the COVID-19 pandemic implications in Brazilian Pediatric and Congenital Heart Surgery programmes. METHODS: We conducted a national online survey covering all states that perform Pediatric and Congenital Heart Surgery from 10 November to 22 November, 2020, using a Google forms questionnaire. We formulated questions related to impact on surgical volume, case-mix, and mortality. Then we asked about short-term post-operative COVID-19 infection and outcomes. RESULTS: We received responses from 46 centres representing all states where there were a Pediatric and Congenital Heart Surgery programme and all high-volume centres across the country. All but one centre experienced a significant decrease in surgical volume, and 23.9% of the responders revealed less than one-quarter of volume decrement. On the other hand, in over 70% of the centres, there was a significant surgical volume reduction. In addition to this, there was a shift in case-mix in 41 centres (89.1%) towards more complex cases. More than one-third of the responders revealed increased mortality in 2020 compared to previous years, and 43.5% of the programmes (20 centres) had at least one patient contaminated by SARS-Cov-2, accounting for 48 patients. Mortality in post-operative infected patients was 45.8% (22 patients). CONCLUSIONS: In general, Brazilian Pediatric and Congenital Heart Surgery programmes were severely affected by decreased surgical volume, unbalanced case-mix towards more complex cases, and increased mortality. Almost half of the programmes related post-operative COVID-19 contamination with high mortality.

Risk factors for death or mechanical ventilation time after bidirectional cavopulmonary anastomosis in a developing country.

BACKGROUND: Glenn procedure is performed for patients with cyanotic CHD and univentricular physiology and has a survival rate above 90%. AIM: To evaluate the risk factors associated with a poor outcome after Glenn procedure. METHODS: The data for this retrospective analysis were collected from a regional Brazilian registry of congenital heart surgeries (ASSIST initiative) from 2014 to 2019. Data from 97 patients who underwent the Glenn procedure were considered. The primary outcomes were prolonged mechanical ventilation (>24 hours post-operatively) or in-hospital death, alone and combined. RESULTS: The overall in-hospital mortality was 13.4% (n = 13). Prolonged mechanical ventilation occurred in 52% (n = 51) of the patients. Our analysis found that risk factors for death or prolonged post-operative mechanical ventilation were cardiopulmonary bypass duration and post-operative lactate, whereas weight-for-age z-score and age at surgery were risk factors for prolonged mechanical ventilation. Cardiopulmonary bypass duration increased (adjusted odds ratio: 1.02; 95 % CI: 1.01, 1.03) and age at surgery decreased (adjusted odds ratio: 0.96; 95 % CI: 0.93, 0.99) the odds of the combined outcome. CONCLUSIONS: Age at surgery, post-operative lactate, and low-weight-for-age z-score are associated with prolonged mechanical ventilation and death following the Glenn procedure.

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.

Anomalous aortic origin of the left main coronary artery associated with arterial compression-Case report.

BACKGROUND: Anomalous aortic origin of coronary artery is a rare finding, with varied presentation and symptomatology. Increasingly recognized by cardiac imaging, when found it raises questions about the appropriate approach and management. CASE PRESENTATION: We present a case of an 11-year-old female who presented with episodes of shortness of breath, angina, and syncope during exercise. Further investigation demonstrated episodes of nonsustained ventricular tachycardia on Holter and coronary angiotomography revealed that the left coronary artery had an anomalous origin from the right cusp with initial short intramural segment and significant external compression in its initial course between the aorta and the pulmonary artery. The patient was submitted to surgical correction with dissection of left coronary artery posterior to the pulmonary artery, coronary arteriotomy, roof ampliation with the autologous pericardium, and creation of neo-ostium in aorta. The patient had a satisfactory postoperative recovery, was discharged on the fifth-day post-op, and remains asymptomatic after 14 months of follow-up. Herein we present surgical video and postoperative echo and computed tomography scan.

Anemia in cardiac surgery - can something bad get worse?

Abstract 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.

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 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.

Reversible pulmonary trunk banding: Myocardial vascular endothelial growth factor expression in young goats submitted to ventricular retraining.

BACKGROUND: Ventricle retraining has been extensively studied by our laboratory. Previous studies have demonstrated that intermittent overload causes a more efficient ventricular hypertrophy. The adaptive mechanisms involved in the ventricle retraining are not completely established. This study assessed vascular endothelial growth factor (VEGF) expression in the ventricles of goats submitted to systolic overload. METHODS: Twenty-one young goats were divided into 3 groups (7 animals each): control, 96-hour continuous systolic overload, and intermittent systolic overload (four 12-hour periods of systolic overload paired with 12-hour resting period). During the 96-hour protocol, systolic overload was adjusted to achieve a right ventricular (RV) / aortic pressure ratio of 0.7. Hemodynamic evaluations were performed daily before and after systolic overload. Echocardiograms were obtained preoperatively and at protocol end to measure cardiac masses thickness. At study end, the animals were killed for morphologic evaluation and immunohistochemical assessment of VEGF expression. RESULTS: RV-trained groups developed hypertrophy of RV and septal masses, confirmed by increased weight and thickness, as expected. In the study groups, there was a small but significantly increased water content of the RV and septum compared with those in the control group (p<0.002). VEGF expression in the RV myocardium was greater in the intermittent group (2.89% ± 0.41%) than in the continuous (1.80% ± 0.19%) and control (1.43% ± 0.18%) groups (p<0.023). CONCLUSIONS: Intermittent systolic overload promotes greater upregulation of VEGF expression in the subpulmonary ventricle, an adaptation that provides a mechanism for increased myocardial perfusion during the rapid myocardial hypertrophy of young goats.

Prognostic value of the preoperative neutrophil-lymphocyte ratio in patients undergoing the bidirectional Glenn procedure.

INTRODUCTION: The neutrophil-lymphocyte ratio (NLR) has been associated with worse outcomes in patients undergoing coronary artery bypass graft surgery. Little is known about this association in the pediatric population who require surgery for congenital heart defects, especially in patients with a single ventricle (SV). OBJECTIVE: To analyze the association of the preoperative NLR with outcomes in patients undergoing the bidirectional Glenn procedure. METHODS: This study involved a retrospective cohort analysis of 141 consecutive patients with SV undergoing the bidirectional Glenn procedure between January 2011 and December 2017 in two centers. The preoperative NLR was included in the last hemogram test before surgery. According to the NLR level, the patients were divided into group I (NLR < 1), group II (NLR between 1 and 2), and group III (NLR > 2). The primary endpoint was total hospital length of stay (LOS), and secondary endpoints were mechanical ventilation (MV) time, intensive care unit (ICU) LOS, ventricular dysfunction, complications, and middle-term mortality. RESULTS: The average follow-up duration was 48 months. There were 61, 47, and 33 patients in groups I, II, and III, respectively. Patients in group III exhibited an increased risk of prolonged total hospital LOS (P = .00). An increase in MV time (P = .03) and ICU LOS (P = .02) was also observed in this group, and these patients experienced greater mortality in 24 months following the surgery (P = .03). There was no association between the NLR and ventricular dysfunction (P = .26) and complications (P = .46). CONCLUSION: A high preoperative NLR was associated with worse outcomes in patients with SV physiology undergoing the bidirectional Glenn procedure.

Impact of vacuum-assisted venous drainage on forward flow in simulated pediatric cardiopulmonary bypass circuits utilizing a centrifugal arterial pump head

Abstract 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.

Early and long-term outcomes of surgical treatment of ebstein's anomaly

Abstract 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 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.