Preoperative Levosimendan in Patients With Severe Left Ventricular Dysfunction Undergoing Isolated Coronary Artery Bypass Grafting: A Meta-Analysis of Randomized Controlled Trials.

OBJECTIVE: To verify the impact of preoperative levosimendan on patients with severe left ventricular dysfunction (ejection fraction <35%) undergoing isolated coronary artery bypass grafting. DESIGN: A meta-analysis. SETTING: Hospitals. PARTICIPANTS: The authors included 1,225 patients from 6 randomized controlled trials. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The authors performed a meta-analysis of trials that compared preoperative levosimendan with placebo or no therapy, reporting efficacy and safety endpoints. Statistical analyses used mean differences and risk ratios (RR), with a random effects model. Six studies were included, comprising 1,225 patients, of whom 615 (50.2%) received preoperative levosimendan, and 610 (49.8%) received placebo/no therapy. Preoperative levosimendan showed a lower risk of all-cause mortality (RR 0.31; 95% CI 0.16-0.60; p < 0.01; I2 = 0%), postoperative acute kidney injury (RR 0.44; 95% CI 0.25-0.77; p < 0.01; I2 = 0%), low-cardiac-output syndrome (RR 0.45; 95% CI 0.30-0.66; p < 0.001; I2 = 0%), and postoperative atrial fibrillation (RR 0.49; 95% CI 0.25-0.98; p = 0.04; I2 = 85%) compared to control. Moreover, levosimendan significantly reduced the need for postoperative inotropes and increased the cardiac index at 24 hours postoperatively. There were no differences between groups for perioperative myocardial infarction, hypotension, or any adverse events. CONCLUSION: Preoperative levosimendan in patients with severe left ventricular dysfunction undergoing isolated coronary artery bypass grafting was associated with reduced all-cause mortality, low-cardiac-output syndrome, acute kidney injury, postoperative atrial fibrillation, and the need for circulatory support without compromising safety.

A novel interpretative tool for early prediction of low cardiac output syndrome after valve surgery: online machine learning models.

OBJECTIVE: Low cardiac output syndrome (LCOS) is a severe complication after valve surgery, with no uniform standard for early identification. We developed interpretative machine learning (ML) models for predicting LCOS risk preoperatively and 0.5 h postoperatively for intervention in advance. METHODS: A total of 2218 patients undergoing valve surgery from June 2019 to Dec 2021 were finally enrolled to construct preoperative and postoperative models. Logistic regression, support vector machine (SVM), random forest classifier, extreme gradient boosting, and deep neural network were executed for model construction, and the performance of models was evaluated by area under the curve (AUC) of the receiver operating characteristic and calibration curves. Our models were interpreted through SHapley Additive exPlanations, and presented as an online tool to improve clinical operability. RESULTS: The SVM algorithm was chosen for modeling due to better AUC and calibration capability. The AUCs of the preoperative and postoperative models were 0.786 (95% CI 0.729-0.843) and 0.863 (95% CI 0.824-0.902), and the Brier scores were 0.123 and 0.107. Our models have higher timeliness and interpretability, and wider coverage than the vasoactive-inotropic score, and the AUC of the postoperative model was significantly higher. Our preoperative and postoperative models are available online at http://njfh-yxb.com.cn:2022/lcos. CONCLUSIONS: The first interpretable ML tool with two prediction periods for online early prediction of LCOS risk after valve surgery was successfully built in this study, in which the SVM model has the best performance, reserving enough time for early precise intervention in critical care.

Frequency of Low Cardiac Output Syndrome Following on Pump Coronary Artery Bypass Grafting Surgery and it's Association with Degree of Pre-operative Left Ventricular Dysfunction.

Background Low cardiac output syndrome (LCOS) is a serious complication after coronary artery bypass grafting (CABG) surgery. It is associated with 10 times to 17 times increase in mortality and markedly increase morbidity. Objective To find out the frequency of Low cardiac output syndrome following on pump coronary artery bypass grafting surgery, to determine the association of Low cardiac output syndrome with degree of pre-operative left ventricular dysfunction and to compare in hospital outcomes of coronary bypass surgery with and without low cardiac output syndrome. Method This prospective, descriptive study enrolled 200 patients who underwent on pump coronary artery bypass grafting surgery using antegrade St Thomas blood cardioplegia. Pre-operatively grouped into two groups consisting Group A of 100 patients with pre-operative left ventricular ejection fraction (LVEF) ≥ 40% and group B of 100 patients with pre-operative left ventricular ejection fraction (LVEF) < 40%. Post-operatively frequency of low cardiac output syndrome was compared between the groups and in-hospital outcomes were studied. Result The mean age of the patients in the study was 53.50±7.57 years. Male to female ratio was 1.8:1. Results showed overall frequency of low cardiac output syndrome was 21.5%. The frequency of LCOS was 15 vs 28% (p - 0.038) in patients with preoperative LV EF ≥ 40% and < 40% respectively. The outcomes of coronary artery bypass grafting surgery were stroke (3.82 vs. 30.23%, p - 0.001), acute kidney injury (5.09 vs. 23.25%, p - 0.001), respiratory failure (6.36 vs. 34.88%, p - 0.001), ICU stay days (4.75 ± 1.28 vs. 7.44 ± 4.66, p - 0.018), hospital stay days (9.56 ± 2.40 vs. 15.22 ± 3.89, p - 0.001) and mortality (4.45 vs. 32.55%, p - 0.001) in patients without and with low cardiac output syndrome respectively. Conclusion The frequency of low cardiac output syndrome following coronary artery bypass surgery is 21.5%. Left ventricular dysfunction pre-operatively is associated with high frequency of low cardiac output syndrome following surgery. There is significantly poor outcome of coronary artery bypass surgery with low cardiac output syndrome in terms of stroke, respiratory failure, acute kidney injury, mortality and significant ICU stay, hospital stay in compare to patients without low cardiac output syndrome.

Development and Validation of a Prediction Score for Low-Cardiac-Output Syndrome After Adult Cardiac Surgery.

OBJECTIVES: The authors aimed to develop a simple prediction score to help identify patients at high risk of low-cardiac-output syndrome after adult cardiac surgery. DESIGN: A single-center, retrospective, observational study. SETTING: At a tertiary hospital. PARTICIPANTS: Adult patients who underwent on-pump cardiac surgery between April 2016 and March 2021. INTERVENTION: None. MEASUREMENTS AND MAIN RESULTS: Among the 2,806 patients retained for final analyses, 355 (12.7%) developed low-cardiac-output syndrome. Using a stepwise backward variable selection procedure applied to a multivariate logistic regression, a prediction model, including 8 risk factors, could be identified-preoperative left ventricular ejection fraction, glomerular filtration rate <60 mL/min according to the Cockcroft formula or preoperative dialysis, combined surgery, nonelective surgery, mitral valve surgery for mitral valve regurgitation, history of extracardiac arteriopathy, preoperative hemoglobin <13 g/dL, and New York Heart Association functional class III or IV. A clinical prediction score was derived from the regression coefficients. The model had a good discriminative ability, with an area under the receiver operating characteristics curve of 0.8 (95% CI: 077-0.84). Using a threshold value of 5, the score had a 68% sensitivity, 79% specificity, a positive-predictive value of 33%, and a negative-predictive value of 94%. These results were validated on a validation sample using the bootstrap resampling technique. CONCLUSIONS: The authors developed a clinical score to facilitate the prediction of low- cardiac-output syndrome after adult cardiac surgery. This could help tailor patient management by contributing to the early identification of those at high risk of postoperative low cardiac output.

Efficacy of perioperative prophylactic administration of corticosteroids in pediatric cardiac surgeries using cardiopulmonary bypass: a systematic review with meta-analysis.

An updated systematic review with meta-analysis comparing perioperative prophylactic administration of corticosteroids with placebo in pediatric cardiac surgeries using cardiopulmonary bypass was conducted. The Cochrane Central Register of Controlled Trials and MEDLINE (via PubMed) were searched for relevant randomized controlled trials published between January 1, 2000, and February 14, 2023. The primary outcome was postoperative in-hospital mortality. Secondary outcomes were duration of mechanical ventilation, length of intensive care unit and hospital stay, postoperative low cardiac output syndrome, and adverse events. A total of 11 studies were included in the meta-analysis. Corticosteroid administration did not decrease postoperative in-hospital mortality compared with placebo (relative risk, 0.69; 95% confidence interval, 0.40-1.17). Subgroup analyses according to the type of corticosteroids and neonates revealed that corticosteroids did not decrease postoperative in-hospital mortality. In the trial sequential analysis, the last point in the z-curve was within the futility borders. Although the duration of mechanical ventilation (mean difference, -5.54 h; 95% confidence interval (CI), -9.75 - -1.34) and incidence of low cardiac output syndrome (relative risk, 0.75; 95% CI, 0.59 - 0.96) decreased with corticosteroid administration, it did not affect the length of intensive care unit (mean difference, -0.28 days; 95% CI, -0.74 - 0.17) and hospital stay (mean difference, -0.59 days; 95% CI, -1.31 - 0.14). In conclusion, perioperative prophylactic corticosteroid administration in pediatric cardiac surgeries using cardiopulmonary bypass did not decrease postoperative in-hospital mortality compared with placebo. According to the trial sequential analysis results, additional randomized controlled trials assessing mortality are not required. PROSPERO REGISTRY NUMBER: CRD 42023391789.

Impact of prophylactic intra-aortic balloon pump on early outcomes in patients with severe left ventricular dysfunction undergoing elective coronary artery bypass grafting with cardiopulmonary bypass.

OBJECTIVE: Our aim was to analyse whether prophylactic preoperative intraaortic balloon pump (IABP) improves outcomes in hemodynamically stable patients with low left ventricular ejection fraction (LVEF ≤30%) undergoing elective myocardial revascularization (CABG) using cardiopulmonary bypass (CPB). Secondary aim was to identify the predictors for low cardiac output syndrome (LCOS). METHODS: Prospectively collected data of 207 consecutive patients with LVEF ≤30% undergoing elective isolated CABG with CPB from 01/2009 to 12/2019, 136 with and 71 patients without IABP, were retrieved retrospectively. Patients with prophylactic IABP were matched 1:1 with patients without IABP by a propensity score matching. Stepwise logistic regression was conducted to identify predictors of postoperative LCOS in the propensity-matched cohort. P value ≤0.05 was considered significant. RESULTS: Reduced postoperative LCOS (9.9% vs. 26.8%, P = 0.017) was observed in patients receiving prophylactic IABP. Stepwise logistic regression identified preoperative IABP as preventive factor for postoperative LCOS [Odds Ratio (OR) 0.19,95% Confidence Interval (CI), 0.06-0.55, P = 0.004]. The need of vasoactive and inotropic support was lower in patients with prophylactic IABP at 24, 48 and 72 h after surgery (12.3 [8.2-18.6] vs. 22.2 [14.4-28.8], P < 0.001, 7.7 [3.3-12.3] vs.16.3 [8.9-27.8], P < 0.001 and 2.4 [0-7] vs. 11.5 [3.1-26], P < 0.001, respectively). The patients in both groups did not differ in terms of in-hospital mortality (7.0% vs. 9.9%, P = 0.763). There were no major IABP-related complications. CONCLUSIONS: Elective patients with left ventricular ejection fraction ≤30% undergoing CABG with CPB and prophylactic IABP insertion had less low cardiac output syndrome and similar in-hospital mortality.

Aortic cross-clamp time correlates with mortality in the mini-mitral international registry.

OBJECTIVES: Minimally invasive access has become the preferred choice in mitral and/or tricuspid valve surgery. Reported outcomes are at least similar to classic sternotomy although aortic cross-clamp times are usually longer. METHODS: We analysed the largest registry of mitral and/or tricuspid valve surgery patients (mini-mitral international registry (MMIR)) for the relationship between aortic cross-clamp times, mortality and other outcomes. From 2015 to 2021, 7513 consecutive patients underwent mini-mitral and/or tricuspid valve surgery in 17 international Heart-Valve-Centres. Data were collected according to Mitral Valve Academic Research Consortium (MVARC) definitions and 6878 patients with 1 cross-clamp period were analysed. Uni- and multivariable regression analyses were used to assess outcomes in relation to aortic cross-clamp times. RESULTS: Median age was 65 years (57% male). Median EuroSCORE II was 1.3% (Inpatient Quality Reporting (IQR): 0.80-2.63). Minimally invasive access was either by direct vision (28%), video-assisted (41%) or totally endoscopic/robotic (31%). Femoral cannulation was used in 93%. Three quarters were repairs with 17% additional tricuspid valve surgery and 19% Atrial Fibrillation (AF)-ablation. Cardiopulmonary bypass and cross-clamp times were 135 min (IQR: 107-173) and 85 min (IQR: 64-111), respectively. Postoperative events were death (1.6%), stroke (1.2%), bleeding requiring revision (6%), low cardiac output syndrome (3.5%) and acute kidney injury (6.2%, mainly stage I). Statistical analyses identified significant associations between cross-clamp time and mortality, low cardiac output syndrome and acute kidney injury (all P < 0.001). Age, low ejection fraction and emergent surgery were risk factors, but variables of 'increased complexity' (redo, endocarditis, concomitant procedures) were not. CONCLUSIONS: Aortic cross-clamp time is associated with mortality as well as postoperatively impaired cardiac and renal function. Thus, implementing measures to reduce cross-clamp time may improve outcomes.

Evaluation of perfusion index and left ventricular output changes in low cardiac output syndrome after arterial switch operation.

INTRODUCTION: Transposition of great arteries is one of newborns' most common cyanotic CHDs, and its treatment is arterial switch operation in the first days of life. Low cardiac output syndrome may develop in the early postoperative period. In this study, we evaluated perfusion index and left ventricular output blood flow changes in patients who underwent arterial switch operation and developed low cardiac output syndrome. METHODS: This study was conducted prospectively in newborns with transposition of great arteries who underwent arterial switch operation between 1st August 2020 and 1st August 2022. Low cardiac output syndrome score and left ventricular output were investigated. Initially, 6th, 12th, 18th, and 24th hour perfusion index and left ventricular output values of patients with and without low cardiac output syndrome were recorded. The results were evaluated statistically. RESULTS: A total of 60 patients were included in the study. Sex distribution was equal. The median age at the time of surgery was 5 days (interquartile range 3-7 days), and the median weight was 3.1 kg (interquartile range 2.9-3. 4). Low cardiac output syndrome was detected in 30% (n = 18) of cases. The median perfusion index of patients who developed low cardiac output syndrome was significantly lower at the 12th, 18th, and 24th hours (p < 0.05) (0.99 versus 1.25, 0.86 versus 1.21, and 0.96 versus 1.33, respectively). Similarly, the median left ventricular output of patients who developed low cardiac output syndrome was significantly lower at 12th, 18th, and 24th hours (p < 0.05) (95 versus 110 ml/kg/min, 89 versus 109 ml/kg/min, and 92 versus 112 ml/kg/min, respectively). There was a significant correlation between perfusion index values and left ventricular output at all measurements (r > 0.500, p < 0.05). CONCLUSION: Perfusion index and left ventricular output measurements decreased in newborns who developed low cardiac output syndrome after arterial switch operation, especially at 12th and 18th hours. Serial perfusion index and left ventricular output measurements can be instructive in predicting low cardiac output syndrome development.

A new machine learning algorithm to predict veno-arterial ECMO implantation after post-cardiotomy low cardiac output syndrome.

BACKGROUND: Post-cardiotomy low cardiac output syndrome (PC-LCOS) is a life-threatening complication after cardiac surgery involving a cardiopulmonary bypass (CPB). Mechanical circulatory support with veno-arterial membrane oxygenation (VA-ECMO) may be necessary in the case of refractory shock. The objective of the study was to develop a machine-learning algorithm to predict the need for VA-ECMO implantation in patients with PC-LCOS. PATIENTS AND METHODS: Patients were included in the study with moderate to severe PC-LCOS (defined by a vasoactive inotropic score (VIS) > 10 with clinical or biological markers of impaired organ perfusion or need for mechanical circulatory support after cardiac surgery) from two university hospitals in Paris, France. The Deep Super Learner, an ensemble machine learning algorithm, was trained to predict VA-ECMO implantation using features readily available at the end of a CPB. Feature importance was estimated using Shapley values. RESULTS: Between January 2016 and December 2019, 285 patients were included in the development dataset and 190 patients in the external validation dataset. The primary outcome, the need for VA-ECMO implantation, occurred respectively, in 16% (n = 46) and 10% (n = 19) in the development and the external validation datasets. The Deep Super Learner algorithm achieved a 0.863 (0.793-0.928) ROC AUC to predict the primary outcome in the external validation dataset. The most important features were the first postoperative arterial lactate value, intraoperative VIS, the absence of angiotensin-converting enzyme treatment, body mass index, and EuroSCORE II. CONCLUSIONS: We developed an explainable ensemble machine learning algorithm that could help clinicians predict the risk of deterioration and the need for VA-ECMO implantation in moderate to severe PC-LCOS patients.

Predictors and associated clinical outcomes of low cardiac output syndrome following cardiac surgery: insights from the LEVO-CTS trial.

AIMS: High-risk cardiac surgery is commonly complicated by low cardiac output syndrome (LCOS), which is associated with high mortality. There are limited data derived from multi-centre studies with adjudicated endpoints describing factors associated with LCOS and its downstream clinical outcomes. METHODS AND RESULTS: The Levosimendan in Patients with Left Ventricular Systolic Dysfunction Undergoing Cardiac Surgery Requiring Cardiopulmonary Bypass (LEVO-CTS) trial evaluated prophylactic levosimendan vs. placebo in patients with a reduced ejection fraction undergoing coronary artery bypass grafting (CABG) and/or valve surgery. We conducted a pre-specified analysis on LCOS, which was characterized by a four-part definition. We constructed a multivariable logistical regression model to evaluate risk factors associated with LCOS and performed Cox proportional hazards modelling to determine the association of LCOS with 90-day mortality. A total of 186 (22%) of 849 patients in the LEVO-CTS trial developed LCOS. The factors most associated with a higher adjusted risk of LCOS were pre-operative ejection fraction [odds ratio (OR) 1.26; 95% confidence interval (CI): 1.08-1.46 per 5% decrease] and age (OR 1.13; 95% CI: 1.04-1.24 per 5-year increase), whereas isolated CABG surgery (OR 0.44, 95% CI: 0.31-0.64) and levosimendan use (OR 0.65; 95% CI: 0.46-0.92) were associated with a lower risk of LCOS. Patients with LCOS had worse outcomes, including renal replacement therapy at 30-day (10 vs. 1%) and 90-day mortality (16 vs. 3%, adjusted hazard ratio of 5.04, 95% CI: 2.66-9.55). CONCLUSION: Low cardiac output syndrome is associated with a high risk of post-operative mortality in high-risk cardiac surgery.

Levosimendan in paediatric cardiac anaesthesiology: A systematic review and meta-analysis.

BACKGROUND: Low cardiac output syndrome (LCOS) after congenital cardiac surgery has an incidence of up to 25%. Preventing and treating LCOS is of pivotal importance as LCOS is associated with excess morbidity and mortality. OBJECTIVES: This systematic review assesses the safety and efficacy of peri-operative levosimendan administration in the setting of paediatric cardiac surgery. DESIGN: Systematic review of randomised controlled trials. Meta-analyses were performed on efficacy and exploratory outcomes. DATA SOURCES: Literature was searched in the following databases (MEDLINE, EMBASE, Web of Science and CENTRAL) from inception to July 2021. ELIGIBILITY CRITERIA: Randomised controlled trials comparing levosimendan with other inotropes or placebo in children younger than 18 years of age undergoing cardiac surgery. RESULTS: Nine studies enrolling a total of 539 children could be included in the systematic review. All trials study the prophylactic administration of levosimendan in comparison with placebo ( n   =  2), milrinone ( n  = 6) or dobutamine ( n   =  1). Levosimendan dosing varied considerably with only three studies using a loading dose. Levosimendan reduced the incidence of LCOS [risk ratio (RR) 0.80] [95% confidence interval (CI), 0.40 to 0.89, P  = 0.01] and increased cardiac index (MD 0.17 l min -1  m -2 ) (95% CI, 0.06 to 0.28, P  = 0.003) without affecting other outcomes (mortality, ICU length of stay, hospital length of stay, duration of mechanical ventilation, serum lactate, central venous oxygen saturation, serum creatine or acute kidney injury). CONCLUSION: The prophylactic use of levosimendan in children undergoing cardiac surgery reduced the incidence of LCOS and increased cardiac index compared with other inotropes or placebo. This effect did not translate into an improvement of other clinical endpoints.

Effect of Nitric Oxide via Cardiopulmonary Bypass on Ventilator-Free Days in Young Children Undergoing Congenital Heart Disease Surgery: The NITRIC Randomized Clinical Trial.

Importance: In children undergoing heart surgery, nitric oxide administered into the gas flow of the cardiopulmonary bypass oxygenator may reduce postoperative low cardiac output syndrome, leading to improved recovery and shorter duration of respiratory support. It remains uncertain whether nitric oxide administered into the cardiopulmonary bypass oxygenator improves ventilator-free days (days alive and free from mechanical ventilation). Objective: To determine the effect of nitric oxide applied into the cardiopulmonary bypass oxygenator vs standard care on ventilator-free days in children undergoing surgery for congenital heart disease. Design, Setting, and Participants: Double-blind, multicenter, randomized clinical trial in 6 pediatric cardiac surgical centers in Australia, New Zealand, and the Netherlands. A total of 1371 children younger than 2 years undergoing congenital heart surgery were randomized between July 2017 and April 2021, with 28-day follow-up of the last participant completed on May 24, 2021. Interventions: Patients were assigned to receive nitric oxide at 20 ppm delivered into the cardiopulmonary bypass oxygenator (n = 679) or standard care cardiopulmonary bypass without nitric oxide (n = 685). Main Outcomes and Measures: The primary end point was the number of ventilator-free days from commencement of bypass until day 28. There were 4 secondary end points including a composite of low cardiac output syndrome, extracorporeal life support, or death; length of stay in the intensive care unit; length of stay in the hospital; and postoperative troponin levels. Results: Among 1371 patients who were randomized (mean [SD] age, 21.2 [23.5] weeks; 587 girls [42.8%]), 1364 (99.5%) completed the trial. The number of ventilator-free days did not differ significantly between the nitric oxide and standard care groups, with a median of 26.6 days (IQR, 24.4 to 27.4) vs 26.4 days (IQR, 24.0 to 27.2), respectively, for an absolute difference of -0.01 days (95% CI, -0.25 to 0.22; P = .92). A total of 22.5% of the nitric oxide group and 20.9% of the standard care group developed low cardiac output syndrome within 48 hours, needed extracorporeal support within 48 hours, or died by day 28, for an adjusted odds ratio of 1.12 (95% CI, 0.85 to 1.47). Other secondary outcomes were not significantly different between the groups. Conclusions and Relevance: In children younger than 2 years undergoing cardiopulmonary bypass surgery for congenital heart disease, the use of nitric oxide via cardiopulmonary bypass did not significantly affect the number of ventilator-free days. These findings do not support the use of nitric oxide delivered into the cardiopulmonary bypass oxygenator during heart surgery. Trial Registration: anzctr.org.au Identifier: ACTRN12617000821392.

[Levosimendan for preventing low output syndrome in pediatric patients with correction of tetralogy of Fallot]. / Levosimendán para prevenir el síndrome de bajo gasto en pacientes pediátricos con corrección de tetralogía de Fallot.

Background: Tetralogy of Fallot is one of the most frequent cyanotic heart diseases in our country, occupying the second place reported by the national health program 2007- 2012 and its prevalence is around 11%. Patients undergoing correction for tetralogy of Fallot are considered patients with a prolonged ischemic time and a high risk of presenting low cardiac output syndrome. Objective: To compare levosimendan with milrinone to prevent low cardiac output syndrome in patients undergoing tetralogy of Fallot correction. Material and methods: Randomized controlled open, prospective, longitudinal and comparative clinical trial. The sample size consisted of 19 patients, with a 95% confidence level. Group 1: levosimendan 0.1 mcg/kg/min from anesthetic induction. Group 2: conventional management with milrinone 0.5 mcg/kg/min. Results: When comparing the final measurements, it can be observed that the mean arterial pressure of the intervention group (levosimendan) was statistically significant (p = 0.04), both in the intraoperative measurement and in the final measurement. When comparing uresis, we found that the intervention group had a greater amount of uresis (p = 0.03). Regarding lactate, both in the intraoperative measurement (p = 0.002) and in the final measurement (p = 0.02), a lower amount was found in the intervention group. Conclusions: The results in favor of the use of levosimendan were reported, demonstrating the prevention of low cardiac output syndrome.

Introducción: la tetralogía de Fallot es una de las cardiopatías cianóticas más frecuentes de nuestro país, pues ocupa el segundo lugar reportado por el Programa Nacional de Salud 2007-2012 y su prevalencia se sitúa aproximadamente en 11%. Los pacientes sometidos a corrección de tetralogía de Fallot se consideran pacientes con un tiempo de isquemia prolongado y con riesgo alto de presentar síndrome de bajo gasto cardiaco. Objetivo: comparar levosimendán con milrinona para prevenir el síndrome de bajo gasto cardiaco en pacientes operados de corrección de tetralogía de Fallot. Material y métodos: ensayo clínico aleatorizado, controlado, abierto, prospectivo, longitudinal y comparativo. El tamaño de la muestra se estimó en 19 pacientes, con un nivel de confianza del 95%. En el grupo 1 se empleó 0.1 mcg/kg/min de levosimendán desde la inducción anestésica; en el grupo 2 se usó el manejo convencional con milrinona de 0.5 mcg/kg/min. Resultados: al comparar las mediciones finales se pudo observar que la presión arterial media del grupo de intervención (levosimendán) fue estadísticamente significativa (p = 0.04), tanto en la medición transoperatoria como en la medición final. Al comparar la uresis encontramos que el grupo con intervención tuvo mayor cantidad de uresis (p = 0.03). En cuanto al lactato, tanto en la medición transoperatoria (p = 0.002) como en la medición final (p = 0.02) se encontró una menor cantidad en el grupo de intervención. Conclusiones: se reportaron los resultados a favor del uso del levosimendán, pues se demostró que previene el síndrome de bajo gasto cardiaco.

Low Cardiac Output Syndrome After Cardiac Surgery: A Life-Threatening Condition from the Perspective of Pediatric Intensivists.

Low cardiac output syndrome is a clinical picture insourcing from insufficient oxygen sup- ply to tissues so as to meet the metabolic demand, myocardial dysfunction, and cardiovas- cular insufficiency. Low cardiac output syndrome is seen in nearly 25% of pediatric patients who underwent corrective or palliative surgery due to congenital heart defects. It is a clinical condition occurring typically 6-18 hours after surgery in pediatric patients undergoing cardiac surgery and causes organ failure, prolonged hospital and intensive care hospitalization time, increased resource utilization, and mortality. The identification and correct management of this serious complication in the early period is very important. However, there is no clear con- sensus or consensus report on the follow-up of this patient group and the definition of low cardiac output syndrome. Clinicians generally produced low cardiac output syndrome defini- tions according to their own approach. In this review, we aim to draw attention to low cardiac output syndrome and hope to summarize the pathophysiology, etiology, clinical definition, and treatment options of low cardiac output syndrome as a life-threatening condition in pediatric intensive care unit.

Procedure-Specific Relationships Between Postoperative Troponin T and a Composite of Mortality and Low Cardiac Output Syndrome: A Retrospective Cohort Analysis.

BACKGROUND: Myocardial injury after coronary artery bypass grafting (CABG) is defined as troponin concentrations >10 times 99th percentile upper reference limit (URL) according to the Fourth Universal Definition. However, troponin concentrations after non-CABG cardiac surgery which indicate greater-than-expected myocardial injury and increased risk for complications remain unclear. Our goal was to assess procedure-specific relationships between troponin T and a composite outcome of low cardiac output syndrome and in-hospital mortality in cardiac surgical patients. METHODS: Patients having cardiac surgery between January 2010 and December 2017 were categorized into 4 groups by procedure: (1) CABG; (2) mitral valve repair; (3) aortic valve repair/replacement (AVR); (4) mitral valve replacement (MVR) or CABG + valve surgeries. Exclusion criteria were elevated preoperative troponin T, preoperative kidney failure, circulatory arrest, or preoperative/planned mechanical circulatory support. Logistic regression was used to assess the association between troponin T and composite outcome, both overall and by procedure, including assessment of the interaction between procedure and troponin T on outcome. RESULTS: Among 10,253 patients, 37 (0.4%) died and 393 (3.8%) developed the primary outcome. Troponin T concentrations differed by procedure (P < .001). Compared to CABG, AVR had 0.53 (99.2% confidence interval [CI], 0.50-0.56; unadjusted P < .001) times lower troponin T concentrations, while MVR/CABG + valve were 1.54 (99.2% CI, 1.45-1.62, unadjusted P < .001) times higher. There were linear relationships between log2 troponin T concentration and log odds mortality/low cardiac output syndrome. The (unadjusted) relationships were parallel for various types of surgery (interaction P = .59), but at different levels of the outcome. CONCLUSIONS: The relative increase in odds for mortality/low cardiac output syndrome per a similar increase in troponin T concentrations did not differ among cardiac surgical procedures, but the absolute troponin T concentrations did. Troponin concentrations should thus be interpreted in context of surgical procedure.

Risk factors, resource use, and cost of postoperative low cardiac output syndrome.

OBJECTIVE: Low cardiac output syndrome complicates recovery after cardiac surgery. We examined the incidence and risk factors for low cardiac output syndrome and its association with postoperative mortality, morbidity, resource use, and cost. METHODS: This cross-sectional retrospective observational study examined patients having cardiac surgery captured in the Premier Healthcare Database. Low cardiac output syndrome was defined as the requirement for postoperative mechanical circulatory support and/or hemodynamic instability requiring prolonged inotropic support. Incidence, risk factors, and association of low cardiac output syndrome with postoperative outcomes, including mortality, hospital and intensive care unit length of stay, hospital readmission, and cost at 30 days, 90 days, and 6 months, were examined. RESULTS: Among 59,810 patients from 164 hospitals having cardiac surgery between July 1, 2012, and June 30, 2014, low cardiac output syndrome developed in 6067 (10.1%) patients. Patients presenting in cardiogenic shock or systolic (± diastolic) heart failure were at greatest risk. Risk-adjusted in-hospital mortality was 12-fold greater with low cardiac output syndrome (odds ratio, 12.0; 95% confidence interval, 10.6-13.5). Risk-adjusted hospital costs (2019$; median [Q1, Q3]) were $64,041 [21,439] in patients who developed low cardiac output syndrome versus $48,086 [16,098] without; P < .001. Increased costs were driven by longer risk-adjusted hospital stay (10.1 [4.5] vs 8.5 [3.8] days); P < .001, intensive care unit (5.5 [2.5] vs 3.3 [1.5] days; P < .001) stay, and all-cause 30-day adjusted hospital readmission rates (mean [SD] 16.6 [8.2]% vs 13.9 [7.2]%; P < .001). CONCLUSIONS: Cardiac surgical patients who develop postoperative low cardiac output syndrome suffer greater mortality and have greater resource use, health care costs, and all-cause readmission, which informs perioperative decision making, and impacts hospital performance metrics and federal priority to reduce health care costs.

The impact of exogenous nitric oxide during cardiopulmonary bypass for cardiac surgery.

OBJECTIVES: Cardiac surgery using cardiopulmonary bypass frequently provokes a systemic inflammatory response syndrome. This can lead to the development of low cardiac output syndrome (LCOS). Both of these can affect morbidity and mortality. This study is a systematic review of the impact of gaseous nitric oxide (gNO), delivered via the cardiopulmonary bypass (CPB) circuit during cardiac surgery, on post-operative outcomes. It aims to summarise the evidence available, to assess the effectiveness of gNO via the CPB circuit on outcomes, and highlight areas of further research needed to develop this hypothesis. METHODS: A comprehensive search of Pubmed, Embase, Web of Science and the Cochrane Library was performed in May 2020. Only randomised control trials (RCTs) were considered. RESULTS: Three studies were identified with a total of 274 patients. There was variation in the outcomes measures used across the studies. These studies demonstrate there is evidence that this intervention may contribute towards cardioprotection. Significant reductions in cardiac troponin I (cTnI) levels and lower vasoactive inotrope scores were seen in intervention groups. A high degree of heterogeneity between the studies exists. Meta-analysis of the duration of mechanical ventilation, length of ICU stay and length of hospital stay showed no significant differences. CONCLUSION: This systematic review explored the findings of three pilot RCTs. Overall the hypothesis that NO delivered via the CPB circuit can provide cardioprotection has been supported by this study. There remains a significant gap in the evidence, further high-quality research is required in both the adult and paediatric populations.

Risks and Outcomes of Reoperative Cardiac Surgery in Patients With Patent Bilateral Internal Thoracic Artery Grafts.

BACKGROUND: Reoperative cardiac surgery in patients with patent bilateral internal thoracic artery (ITA) grafts is technically challenging. METHODS: From 2008 to 2017, of 7640 patients undergoing reoperative cardiac surgery, 116 (1.5%) had patent bilateral ITA grafts, including 28 with a right ITA crossing the midline. Mean age was 70 ± 9.6 years, and 111 patients (96%) were men. Reoperations included isolated coronary artery bypass grafting (n = 11), isolated valve (n = 55), valve + coronary artery bypass grafting (n = 26), and other procedures (n = 24). Clinical details, intraoperative management, and perioperative outcomes were analyzed. RESULTS: Aortic cannulation was central in 64 patients (56%) and through the femoral or axillary artery in 50 (44%). Four patients (3.4%) had planned transection and reattachment of ITAs crossing the midline, and 4 (3.4%) had ITA injuries, all right ITAs, 3 crossing the midline; 3 were repaired with an interposition vein graft, and 1 was managed by translocating the right ITA as a Y-graft off another graft. Patent ITAs were managed by atraumatic occlusion during aortic clamping in 90 patients (78%) and by systemic cooling without ITA occlusion in 19. There were 6 operative deaths, all due to low cardiac output syndrome (5.2%); 4 strokes (3.4%); and 5 cases of new postoperative dialysis (4.3%). CONCLUSIONS: Risk of injury to bilateral ITA grafts during reoperation is high, and right ITAs crossing the midline present a particular risk of injury and should inform planning for primary coronary artery bypass grafting. Risk of low cardiac output syndrome underscores the challenge of ensuring adequate myocardial protection.

The multivariable prognostic models for severe complications after heart valve surgery.

BACKGROUND: To provide multivariable prognostic models for severe complications prediction after heart valve surgery, including low cardiac output syndrome (LCOS), acute kidney injury requiring hemodialysis (AKI-rH) and multiple organ dysfunction syndrome (MODS). METHODS: We developed multivariate logistic regression models to predict severe complications after heart valve surgery using 930 patients collected retrospectively from the first affiliated hospital of Sun Yat-Sen University from January 2014 to December 2015. The validation was conducted using a retrospective dataset of 713 patients from the same hospital from January 2016 to March 2017. We considered two kinds of prognostic models: the PRF models which were built by using the preoperative risk factors only, and the PIRF models which were built by using both of the preoperative and intraoperative risk factors. The least absolute shrinkage selector operator was used for developing the models. We assessed and compared the discriminative abilities for both of the PRF and PIRF models via the receiver operating characteristic (ROC) curve. RESULTS: Compared with the PRF models, the PIRF modes selected additional intraoperative factors, such as auxiliary cardiopulmonary bypass time and combined tricuspid valve replacement. Area under the ROC curves (AUCs) of PRF models for predicting LCOS, AKI-rH and MODS are 0.565 (0.466, 0.664), 0.688 (0.62, 0.757) and 0.657 (0.563, 0.751), respectively. As a comparison, the AUCs of the PIRF models for predicting LOCS, AKI-rH and MODS are 0.821 (0.747, 0.896), 0.78 (0.717, 0.843) and 0.774 (0.7, 0.847), respectively. CONCLUSIONS: Adding the intraoperative factors can increase the predictive power of the prognostic models for severe complications prediction after heart valve surgery.

Analysis of risk factors of low cardiac output syndrome after congenital heart disease operation: what can we do.

BACKGROUND: It's necessary to analyze the related risk factors and complications of low cardiac output syndrome (LCOS) after operation in children with congenital heart disease (CHD), to elucidate the management strategy of LCOS. METHODS: CHD children admitted to the department of cardiology in our hospital from January 15, 2019 to October 31, 2020 were included. The personal and clinical data of CHD children with LCOS and without LCOS were collected and compared. Logistic regression analyses were conducted to identify the risk factors of postoperative LCOS. Besides, the complication and mortality of LCOS and no LCOS patients were compared. RESULTS: A total of 283 CHD patients were included, the incidence of postoperative LCOS in CHD patients was 12.37%. There were significant differences in the age, preoperative oxygen saturation, two-way ventricular shunt, duration of CPB and postoperative residual shunt between two groups (all p < 0.05). Logistic regression analyses indicated that age ≤ 4y(OR2.426, 95%CI1.044 ~ 4.149), preoperative oxygen saturation ≤ 93%(OR2.175, 95%CI1.182 ~ 5.033), two-way ventricular shunt (OR3.994, 95%CI1.247 ~ 6.797), duration of CPB ≥ 60 min(OR2.172, 95%CI1.002 ~ 4.309), postoperative residual shunt (OR1.487, 95%CI1.093 ~ 2.383) were the independent risk factors of LCOS in patients with CHD (all p < 0.05). There were significant differences in the acute liver injury, acute kidney injury, pulmonary infection, tracheotomy, duration of mechanical ventilation, length of ICU stay and mortality (all p < 0.05), no significant difference in the 24 h drainage was found(p = 0.095). CONCLUSION: LCOS after CHD is common, more attentions should be paid to those patients with age ≤ 4y, preoperative oxygen saturation ≤ 93%, two-way ventricular shunt, duration of CPB ≥ 60 min, postoperative residual shunt to improve the prognosis of CHD patients.