Low-Cardiac-Output Syndrome After Cardiac Surgery

Relationship of Fibroblast Growth Factor 23 With Hospitalization for Heart Failure and Cardiovascular Outcomes in Patients Undergoing Cardiac Surgery

Background Fibroblast growth factor 23 (FGF-23) is crucial in regulating phosphate and vitamin D metabolism and is moreover associated with an increased cardiovascular risk. The specific objective of this study was to investigate the influence of FGF-23 on cardiovascular outcomes, including hospitalization for heart failure (HHF), postoperative atrial fibrillation, and cardiovascular death, in an unselected patient population after cardiac surgery. Methods and Results Patients undergoing elective coronary artery bypass graft and/or cardiac valve surgery were prospectively enrolled. FGF-23 blood plasma concentrations were assessed before surgery. A composite of cardiovascular death/HHF was chosen as primary end point. A total of 451 patients (median age 70 years; 28.8% female) were included in the present analysis and followed over a median of 3.9 years. Individuals with higher FGF-23 quartiles showed elevated incidence rates of the composite of cardiovascular death/HHF (quartile 1, 7.1%; quartile 2, 8.6%; quartile 3, 15.1%; and quartile 4, 34.3%). After multivariable adjustment, FGF-23 modeled as a continuous variable (adjusted hazard ratio for a 1-unit increase in standardized log-transformed biomarker, 1.82 [95% CI, 1.34-2.46]) as well as using predefined risk groups and quartiles remained independently associated with the risk of cardiovascular death/HHF and the secondary outcomes, including postoperative atrial fibrillation. Reclassification analysis indicated that the addition of FGF-23 to N-terminal pro-B-type natriuretic peptide provides a significant improvement in risk discrimination (net reclassification improvement at the event rate, 0.58 [95% CI, 0.34-0.81]; P<0.001; integrated discrimination increment, 0.03 [95% CI, 0.01-0.05]; P<0.001). Conclusions FGF-23 is an independent predictor of cardiovascular death/HHF and postoperative atrial fibrillation in individuals undergoing cardiac surgery. Considering an individualized risk assessment, routine preoperative FGF-23 evaluation may improve detection of high-risk patients.

Epidemiology, risk factors and outcomes of norepinephrine use in cardiac surgery with cardiopulmonary bypass: a multicentric prospective study

BACKGROUND

The present study was designed to describe the prevalence of norepinephrine use, the factors associated with its use, and the incidence of postoperative complications according to norepinephrine use, in patients undergoing cardiac surgery with cardiopulmonary bypass.

METHOD

We performed a prospective, multicenter, observational study in 4 University-affiliated medico-surgical cardiovascular units. We analyzed all patients treated with cardiac surgery after excluding pre-ECMO surgery, LVAD implantation, heart transplantation and intra-operative hemorrhage.

RESULTS

Of 9316 patients screened during the study period, 2862 were included and 2510 were analyzed. Among them, 1549 (61%) were treated with norepinephrine with a median maximal dose of 0.11 [0.06-0.2] μg.kg^-1.min^-1 and a median duration of 10 h [2-24]. Norepinephrine was most often started in the operating room before cardiopulmonary bypass. The multiple regression logistic analysis identified several modifiable (haematocrit, maintenance of beta-blocker, cardiopulmonary bypass time, glucose-insulin-potassium, Custodiol cardioplegia, Delnido cardioplegia, and fibrinogen transfusion) and non-modifiable factors (age, ASA score, chronic high blood pressure, coronary disease, dyslipidemia, right ventricular dysfunction, left ventricular dysfunction, active endocarditis, and valvular aortic surgery) associated with norepinephrine use. Mortality, morbidity (neurological and renal complications, death) and length of stay in the ICU were higher in patients treated with norepinephrine.

CONCLUSION

Norepinephrine is often used in cardiac surgical patients but for <24 h with a low dose. Many preoperative and surgical factors are associated with norepinephrine use. Patients supported by norepinephrine have a higher incidence of major postoperative events.

Mitral Valve Surgery in Patients With an Implanted Amplatzer Septal Occluder: A Review of 2 Cases

Surgical approaches for mitral valve exploration vary, with the preferred approach being via the interatrial groove. Data on whether the interatrial groove approach can be used for mitral valve surgery in patients with a previously implanted Amplatzer septal occluder (ASO) (St Jude Medical, an Abbott company) are extremely limited. The authors performed mitral valve surgery using the transatrial septal approach on 2 patients following explantation of an ASO, which significantly impedes the interatrial groove approach. Concomitant surgical procedures with mitral valve replacement, removal of the ASO, and closure of an atrial septal defect with a patch significantly prolonged the cross-clamp and cardiopulmonary bypass durations, which is the reason for intraoperative low cardiac output syndrome. An intra-aortic balloon pump and venoarterial extra-corporeal membrane oxygenation were used in these 2 patients because of low cardiac output syndrome. When planning mitral valve surgery in patients with a previously implanted ASO, the device precludes the interatrial groove approach and can produce an unpredictable clinical scenario.

The relationship between pre-operative right ventricular longitudinal strain and low-cardiac-output syndrome after surgical aortic valve replacement

Objectives

This study was performed to investigate the relationship between right ventricular free wall longitudinal strain (RVFWSL) and low cardiac output syndrome (LCOS) after surgical aortic valve replacement (SAVR) and to further explore its association with readmission within 2 years in patients who developed LCOS after SAVR.

Methods

This single-center retrospective observational study involved consecutive patients who underwent SAVR at our hospital from May 2018 to June 2020. Preoperative echocardiography was obtained within 3 days before SAVR. The longitudinal strain of the right ventricle was analyzed using the right ventricle as the main section, and the RVFWSL and right ventricular four-chamber longitudinal strain (RV4CSL) were obtained. The primary observation was the occurrence of LCOS. The secondary prognostic indicators were mainly the readmission rates within 2 years.

Results

In total, 146 patients were finally included in this study. The RVFWSL was significantly lower in the LCOS group than in the No-LCOS group (16.63 ± 2.10) vs. (23.95 ± 6.33), respectively; P < 0.001). The multivariate regression analysis showed that the RVFWSL was associated with LCOS (odds ratio, 1.676; 95% confidence interval, 1.258-2.232; P < 0.001). The receiver operating characteristic curve showed that the cut-off value for RVFWSL to predict LCOS was less than -18.3, with an area under the curve of 0.879, sensitivity of 100%, and specificity of 80.47%. The multivariate regression analysis showed that LCOS was an independent risk factor for readmission within 2 years in patients undergoing SAVR.

Conclusion

Patients with RVFWSL (<-18.3%) may be an increased risker for LCOS after SAVR. The occurrence of LCOS after SAVR is Yong-jian Zhang a risk factor for readmission within 2 years. Right ventricular function monitoring may have some predictive value for the postoperative prognosis in patients undergoing SAVR.

Study of the accuracy of a radial arterial pressure waveform cardiac output measurement device after cardiac surgery

BACKGROUND

Less invasive monitoring, such as radial arterial pulse contour analysis (ProAQT® sensor), represents an alternative when hemodynamic monitoring is necessary to guide postoperative management and invasive monitoring is not technically feasible. The aim of the study is to evaluate the accuracy of the ProAQT® sensor cardiac output measurements in comparison with Pulmonary Artery Catheter (PAC) during the postoperative course of patients who underwent cardiac surgery with cardiopulmonary bypass.

CASE PRESENTATION

Prospective observational study in a Surgical Intensive Care Unit of a tertiary university hospital. Ten patients with a mean age of 73.5 years were included. The main comorbidities were hypertension, diabetes, dyslipidemia and the preoperative left ejection fraction was 43.8 ± 14.5%. Regarding the type of surgery, six patients underwent valve surgery, two underwent coronary artery bypass grafting and two underwent aortic surgery. The cardiac index measured simultaneously by the ProAQT® sensor was compared with the PAC. The parameters were evaluated at predefined time points during the early postoperative courses (6 h, 12 h, 24 h, 48 h and 72 h). The degree of agreement with the cardiac index between the PAC and the ProAQT® sensor along the time points was measured using the concordance correlation coefficient, Bland-Altman analysis, and four-quadrant plot. Sixty-three pairs of measurements were analyzed. We showed that measurements of cardiac index were slightly higher with PAC (β ̂ = - 0.146, p-value = 0.094). The concordance correlation coefficient for the additive model of cardiac index was 0.64 (95% Confidence Interval: 0.36, 0.82), indicating a high concordance between both sensors. Bland-Altmann analysis showed a mean bias of 0.45 L·min^-1·m^-2, limits of agreement from - 1.65 to 2.3 L·min^-1·m^-2, and percentage of error was 82.5%. Four-quadrant plot of changes in cardiac index showed a good concordance rate (75%), which increases after applying the exclusion zone (87%).

CONCLUSIONS

In patients undergoing cardiac surgery, the ProAQT® sensor may be useful to monitor cardiac index during the postoperative period, especially when more invasive monitoring is not possible.

Single-Dose St. Thomas Versus Custodiol® Cardioplegia for Right Mini-thoracotomy Mitral Valve Surgery

OBJECTIVE

Custodiol® and St. Thomas cardioplegia are widely employed in mini-thoracotomy mitral valve (MV) operations. One-dose of the former provides 3 h of myocardial protection. Conversely, St. Thomas solution is usually reinfused every 30 min and safety of single delivery is unknown. We aimed to compare single-shot St. Thomas versus Custodiol® cardioplegia.

METHODS

Primary endpoint of the prospective observational study was cardiac troponin T level at different post-operative time-points. Propensity-weighted treatment served to adjust for confounding factors.

RESULTS

Thirty-nine patients receiving St. Thomas were compared with 25 patients receiving Custodiol® cardioplegia; cross-clamping always exceeded 45 min. No differences were found in postoperative markers of myocardial injury. Ventricular fibrillation at the resumption of electric activity was more frequent following Custodiol® cardioplegia (P = .01).

CONCLUSION

Effective myocardial protection exceeding 1 h of ischemic arrest can be achieved with a single-dose St. Thomas cardioplegia in selected patients undergoing right mini-thoracotomy MV surgery.

Average and Interindividual Effects to a Comprehensive Cardiovascular Rehabilitation Program

Background: To describe the average effects and the interindividual variability after a comprehensive outpatient cardiovascular rehabilitation (CCR) program using concurrent exercise training prescribed according to cardiovascular risk stratification on cardiorespiratory fitness (CRF), anthropometric/body composition, quality of life and emotional health in patients of four cardiovascular disease profiles. Methods: CRF, anthropometric/body composition, quality of life, and emotional health were measured before and after a CCR and analyzed in heart valve surgery (HVS), heart failure with reduced ejection fraction (HFrEF), post-acute myocardial infarction (post-AMI), and in coronary artery disease (CAD) patients. Twenty, twenty-four, and thirty-two exercise sessions were prescribed according to mild, moderate, and severe baseline cardiovascular risk, respectively. In addition to concurrent exercise training, nutritional counseling, psychological support, and lifestyle education programs were performed. Results: The main outcomes by delta changes comparisons (Δ) revealed no significant differences at anthropometric/body composition as ΔBody fat decreases (HVS Δ−1.1, HFrEF Δ−1.0, post-AMI Δ−1.4, CAD Δ−1.2 kg) and ΔSkeletal muscle mass increases (HVS Δ+1.4, HFrEF Δ+0.8, post-AMI Δ+0.9, CAD Δ+0.9 kg), and CRF performance as ΔVO2peak increases (HVS Δ+4.3, HFrEF Δ+4.8, post-AMI Δ+4.1, CAD Δ+5.1 mL/kg/min) outcomes among HVS, HFrEF, post-AMI, and CAD (p > 0.05). Secondary outcomes showed significant pre-post delta changes in METs (HVS Δ+1.8, HFrEF Δ+0.7, post-AMI Δ+1.4, CAD Δ+1.4), and maximal O2pulse (HVS Δ+3.1, post-AMI Δ+2.1, CAD Δ+1.9). In addition, quality of life had a significant improvement in physical functioning (HVS Δ+17.0, HFrEF Δ+12.1, post-AMI Δ+9.8, CAD Δ+11.2), physical role (HVS Δ+28.4, HFrEF Δ+26.8, post-AMI Δ+25.6, CAD Δ+25.3), vitality (HVS Δ+18.4, HFrEF Δ+14.3, post-AMI Δ+14.2, CAD Δ+10.6) and social functioning (HVS Δ+20.4, HFrEF Δ+25.3, post-AMI Δ+20.4, CAD Δ+14.8) in all cardiovascular disease. For anxiety (HVS Δ−3.6, HFrEF Δ−2.3, post-AMI Δ−3.0, CAD Δ−3.1) and depression (HVS Δ−2.8, HFrEF Δ−3.4, post-AMI Δ−3.2, CAD Δ−2.3) significant changes were also observed. Conclusions: A CCR program that prescribes the number of exercise sessions using a cardiovascular risk stratification improves CRF, QoL, and emotional health, and the average results show a wide interindividual variability (~25% of non-responders) in this sample of four CVD profile of patients.

Perioperative Management of the Patient at High-Risk for Cardiac Surgery-Associated Acute Kidney Injury

Acute kidney injury (AKI) is one of the most common major complications of cardiac surgery, and is associated with increased morbidity and mortality. Cardiac surgery-associated AKI has a complex, multifactorial etiology, including numerous factors such as primary cardiac dysfunction, hemodynamic derangements of cardiac surgery and cardiopulmonary bypass, and the possibility of a large volume of blood transfusion. There are no truly effective pharmacologic therapies for the management of AKI, and, therefore, anesthesiologists, intensivists, and cardiac surgeons must remain vigilant and attempt to minimize the risk of developing renal dysfunction. This narrative review describes the current state of the scientific literature concerning the specific aspects of cardiac surgery-associated AKI, and presents it in a chronological fashion to aid the perioperative clinician in their approach to this high-risk patient group. The evidence was considered for risk prediction models, preoperative optimization, and the intraoperative and postoperative management of cardiac surgery patients to improve renal outcomes.

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.

Acute Cardiac Care for Neonatal Heart Disease

This manuscript is one component of a larger series of articles produced by the Neonatal Cardiac Care Collaborative that are published in this supplement of Pediatrics. In this review article, we summarize the contemporary physiologic principles, evaluation, and management of acute care issues for neonates with complex congenital heart disease. A multidisciplinary team of authors was created by the Collaborative's Executive Committee. The authors developed a detailed outline of the manuscript, and small teams of authors were assigned to draft specific sections. The authors reviewed the literature, with a focus on original manuscripts published in the last decade, and drafted preliminary content and recommendations. All authors subsequently reviewed and edited the entire manuscript until a consensus was achieved. Topics addressed include cardiopulmonary interactions, the pathophysiology of and strategies to minimize the development of ventilator-induced low cardiac output syndrome, common postoperative physiologies, perioperative bleeding and coagulation, and common postoperative complications.

Prediction of Postoperative Deterioration in Cardiac Surgery Patients Using Electronic Health Record and Physiologic Waveform Data

BACKGROUND

Postoperative hemodynamic deterioration among cardiac surgical patients can indicate or lead to adverse outcomes. Whereas prediction models for such events using electronic health records or physiologic waveform data are previously described, their combined value remains incompletely defined. The authors hypothesized that models incorporating electronic health record and processed waveform signal data (electrocardiogram lead II, pulse plethysmography, arterial catheter tracing) would yield improved performance versus either modality alone.

METHODS

Intensive care unit data were reviewed after elective adult cardiac surgical procedures at an academic center between 2013 and 2020. Model features included electronic health record features and physiologic waveforms. Tensor decomposition was used for waveform feature reduction. Machine learning-based prediction models included a 2013 to 2017 training set and a 2017 to 2020 temporal holdout test set. The primary outcome was a postoperative deterioration event, defined as a composite of low cardiac index of less than 2.0 ml min-1 m-2, mean arterial pressure of less than 55 mmHg sustained for 120 min or longer, new or escalated inotrope/vasopressor infusion, epinephrine bolus of 1 mg or more, or intensive care unit mortality. Prediction models analyzed data 8 h before events.

RESULTS

Among 1,555 cases, 185 (12%) experienced 276 deterioration events, most commonly including low cardiac index (7.0% of patients), new inotrope (1.9%), and sustained hypotension (1.4%). The best performing model on the 2013 to 2017 training set yielded a C-statistic of 0.803 (95% CI, 0.799 to 0.807), although performance was substantially lower in the 2017 to 2020 test set (0.709, 0.705 to 0.712). Test set performance of the combined model was greater than corresponding models limited to solely electronic health record features (0.641; 95% CI, 0.637 to 0.646) or waveform features (0.697; 95% CI, 0.693 to 0.701).

CONCLUSIONS

Clinical deterioration prediction models combining electronic health record data and waveform data were superior to either modality alone, and performance of combined models was primarily driven by waveform data. Decreased performance of prediction models during temporal validation may be explained by data set shift, a core challenge of healthcare prediction modeling.

EDITOR’S PERSPECTIVE

Predictors and clinical outcomes of post-coronary artery bypass grafting cerebrovascular strokes

BACKGROUND

Despite the improved medical and surgical managements, still there is a significant risk of developing acute cerebrovascular strokes after coronary artery bypass grafting (CABG). Our objectives were to study the immediate and long-term outcomes after CABG and to identify the possible predictors of post-CABG strokes.

RESULTS

Between January 2016 and August 2020, 410 adult patients, mostly males (82.2%), were retrospectively enrolled after CABG. Acute postoperative strokes occurred in 31 (7.5%) patients; of them, 30 (96.8%) patients had ischemic stroke, while 1 (3.2%) had hemorrhagic stroke. Mechanical thrombectomy was done in two cases. The patients who developed acute cerebral stroke had significantly higher admission (p = 0.02) and follow-up (p < 0.001) SOFA scores, higher arterial blood lactate level (p < 0.001), longer hospitalization (p < 0.001) and more hospital mortality (p < 0.001) compared with the patients who did not develop stroke. Kaplan-Meier curves for 5-year mortality showed increased risk in those patients with postoperative stroke (HR: 23.03; 95% CI: 6.10-86.92, p < 0.001). After multivariate regression, the predictors of early postoperative stroke were carotid artery stenosis (CAS), postoperative atrial fibrillation, cardiopulmonary bypass time, prior cerebral stroke, admission SOFA score and chronic kidney disease (CKD). The predictors of late cerebrovascular stroke were CAS, combined CABG and valve surgery, CKD, atrial fibrillation, prior stroke and HbA1c.

CONCLUSIONS

The development of post-CABG acute cerebrovascular stroke is associated with longer hospitalization, multiple morbidities and increased mortality. Careful assessment and management of risk factors especially atrial fibrillation and carotid artery stenosis should be implemented to decrease this substantial complication after CABG.

Definitions of low cardiac output syndrome after cardiac surgery and their effect on the incidence of intraoperative LCOS: A literature review and cohort study

Objectives

Low cardiac output syndrome (LCOS) is a serious complication after cardiac surgery. Despite scientific interest in LCOS, there is no uniform definition used in current research and clinicians cannot properly compare different study findings. We aimed to collect the LCOS definitions used in literature and subsequently applied the definitions obtained to existing data to estimate their effect on the intraoperative LCOS incidences in adults, children and infants.

Design

This is a literature review, followed by a retrospective cohort study.

Setting

This is a single-institutional study from a university hospital in the Netherlands.

Participants

Patients from all ages undergoing cardiac surgery with cardiopulmonary bypass between June 2011 and August 2018.

Interventions

We obtained different definitions of LCOS used in the literature and applied these to data obtained from an anesthesia information management system to estimate intraoperative incidences of LCOS. We compared intraoperative incidences of LCOS in different populations based on age (infants, children and adults).

Measurements and main results

The literature search identified 262 LCOS definitions, that were applied to intraoperative data from 7,366 patients. Using the 10 most frequently published LCOS definitions, the obtained incidence estimates ranged from 0.4 to 82% in infants, from 0.6 to 56% in children and from 1.5 to 91% in adults.

Conclusion

There is an important variety in definitions used to describe LCOS. When applied to data obtained from clinical care, these different definitions resulted in large distribution of intraoperative LCOS incidence rates. We therefore advocate for standardization of the LCOS definition to improve clinical understanding and enable adequate comparison of outcomes and treatment effects both in daily care and in research.

Impact of lactate dehydrogenase on prognosis of patients undergoing cardiac surgery

Background

Lactate dehydrogenase (LDH) has been reported in multiple heart diseases. Herein, we explored the prognostic effects of preoperative LDH on adverse outcomes in cardiac surgery patients.

Methods

Retrospective data analysis was conducted from two large medical databases: Medical Information Mart for Intensive Care (MIMIC) III and MIMIC IV databases. The primary outcome was in-hospital mortality, whereas the secondary outcomes were 1-year mortality, continuous renal replacement therapy, prolonged ventilation, and prolonged length of intensive care unit and hospital stay.

Results

Patients with a primary endpoint had significantly higher levels of LDH (p < 0.001). Multivariate regression analysis presented that elevated LDH was independently correlated with increased risk of primary and secondary endpoints (all p < 0.001). Subgroup analyses showed that high LDH was consistently associated with primary endpoint. Moreover, LDH exhibited the highest area under the curve (0.768) for the prediction of primary endpoint compared to the other indicators, including neutrophil–lymphocyte ratio (NLR), lymphocyte-monocyte ratio (LMR), platelet–lymphocyte ratio (PLR), lactate, and simplified acute physiology score (SAPS) II. The above results were further confirmed in the MIMIC IV dataset.

Conclusions

Elevated preoperative LDH may be a robust predictor of poor prognosis in cardiac surgery patients, and its predictive ability is superior to NLR, LMR, PLR, lactate, and SAPS II.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-022-02848-7.

Prediction of low cardiac output syndrome in patients following cardiac surgery using machine learning

Background

This study aimed to develop machine learning models to predict Low Cardiac Output Syndrome (LCOS) in patients following cardiac surgery using machine learning algorithms.

Methods

The clinical data of cardiac surgery patients in Nanjing First Hospital between June 2019 and November 2020 were retrospectively extracted from the electronic medical records. Six conventional machine learning algorithms, including logistic regression, support vector machine, decision tree, random forest, extreme gradient boosting and light gradient boosting machine, were employed to construct the LCOS predictive models with all predictive features (full models) and selected predictive features (reduced models). The discrimination of these models was evaluated by the area under the receiver operating characteristic curve (AUC) and the calibration of the models was assessed by the calibration curve. Shapley Additive explanation (SHAP) and Local Interpretable Model-Agnostic Explanations (LIME) were used to interpret the predictive models.

Results

Data from 1,585 patients [982 (62.0%) were male, aged 18 to 88, 212 (13.4%) with LCOS] were employed to train and validate the LCOS models. Among the full models, the RF model (AUC: 0.909, 95% CI: 0.875–0.943; Sensitivity: 0.849, 95% CI: 0.724–0.933; Specificity: 0.835, 95% CI: 0.796–0.869) and the XGB model (AUC: 0.897, 95% CI: 0.859–0.935; Sensitivity: 0.830, 95% CI: 0.702–0.919; Specificity: 0.809, 95% CI: 0.768–0.845) exhibited well predictive power for LCOS. Eleven predictive features including left ventricular ejection fraction (LVEF), first post-operative blood lactate (Lac), left ventricular diastolic diameter (LVDd), cumulative time of mean artery blood pressure (MABP) lower than 65 mmHg (MABP &lt; 65 time), hypertension history, platelets level (PLT), age, blood creatinine (Cr), total area under curve above threshold central venous pressure (CVP) 12 mmHg and 16 mmHg, and blood loss during operation were used to build the reduced models. Among the reduced models, RF model (AUC: 0.895, 95% CI: 0.857–0.933; Sensitivity: 0.830, 95% CI: 0.702–0.919; Specificity: 0.806, 95% CI: 0.765–0.843) revealed the best performance. SHAP and LIME plot showed that LVEF, Lac, LVDd and MABP &lt; 65 time significantly contributed to the prediction model.

Conclusion

In this study, we successfully developed several machine learning models to predict LCOS after surgery, which may avail to risk stratification, early detection and management of LCOS after cardiac surgery.

Machine learning approach identified clusters for patients with low cardiac output syndrome and outcomes after cardiac surgery

BACKGROUND

Low cardiac output syndrome (LCOS) is the most serious physiological abnormality with high mortality for patients after cardiac surgery. This study aimed to explore the multidimensional data of clinical features and outcomes to provide individualized care for patients with LCOS.

METHODS

The electronic medical information of the intensive care units (ICUs) was extracted from a tertiary hospital in South China. We included patients who were diagnosed with LCOS in the ICU database. We used the consensus clustering approach based on patient characteristics, laboratory data, and vital signs to identify LCOS subgroups. The consensus clustering method involves subsampling from a set of items, such as microarrays, and determines to cluster of specified cluster counts (k). The primary clinical outcome was in-hospital mortality and was compared between the clusters.

RESULTS

A total of 1,205 patients were included and divided into three clusters. Cluster 1 (n = 443) was defined as the low-risk group [in-hospital mortality =10.1%, odds ratio (OR) = 1]. Cluster 2 (n = 396) was defined as the medium-risk group [in-hospital mortality =25.0%, OR = 2.96 (95% CI = 1.97-4.46)]. Cluster 3 (n = 366) was defined as the high-risk group [in-hospital mortality =39.2%, OR = 5.75 (95% CI = 3.9-8.5)].

CONCLUSION

Patients with LCOS after cardiac surgery could be divided into three clusters and had different outcomes.

Predictors of low cardiac output after isolated pericardiectomy: an observational study

Background

Low cardiac output is the main cause of perioperative death after pericardiectomy for constrictive pericarditis. We investigated the associated risk factors and consequences.

Methods

We selected constrictive pericarditis patients undergoing isolated pericardiectomy from January 2013 to January 2021. Postoperative low cardiac output was defined as requiring mechanical circulatory support or more than one inotrope to maintain a cardiac index > 2.2 L •min⁻¹ •m⁻² without hypoperfusion, despite adequate filling status. Uni- and multivariable analysis were used to identify factors associated with low cardiac output. Cox regression was used to identify factors associated with length of hospital stay.

Results

Among 212 patients with complete data, 55 (25.9%) developed low cardiac output within postoperative day 1 (quartiles 1 and 2), which caused seven of the nine perioperative deaths. The rates of atrial arrhythmia, renal dysfunction, hypoalbuminemia, modest-to-severe hyponatremia, and hyperbilirubinemia caused by constrictive pericarditis were 9.4%, 12.3%, 49.1%, 10.4%, and 81.6%. The mean preoperative central venous pressure and cardiac index were 18 ± 5 cmH₂O and 1.87 ± 0.45 L•min⁻¹•m⁻². Univariable analysis showed that low cardiac output patients had higher rates of atrial arrhythmia (OR 3.32 [1.35, 8.17], P = 0.007), renal dysfunction (OR 4.24 [1.94, 9.25], P < 0.001), hypoalbuminemia (OR 1.99 [1.06, 3.73], P = 0.031) and hyponatremia (OR 6.36 [2.50, 16.20], P < 0.001), greater E peak velocity variation (difference 2.8 [0.7, 5.0], P = 0.011), higher central venous pressure (difference 3 [2,5] cmH₂O, P < 0.001) and lower cardiac index (difference − 0.27 [− 0.41, − 0.14] L•min⁻¹•m⁻², P < 0.001) than patients without low cardiac output. Multivariable regression showed that atrial arrhythmia (OR 4.04 [1.36, 12.02], P = 0.012), renal dysfunction (OR 2.64 [1.07, 6.50], P = 0.035), hyponatremia (OR 3.49 [1.19, 10.24], P = 0.023), high central venous pressure (OR 1.17 [1.08, 1.27], P < 0.001), and low cardiac index (OR 0.36 [0.14, 0.92], P = 0.032) were associated with low cardiac output (AUC 0.79 [0.72–0.86], P < 0.001). Cox regression analysis showed that hyperbilirubinemia (HR 0.66 [0.46, 0.94], P = 0.022), renal dysfunction (HR 0.51 [0.33, 0.77], P = 0.002), and low cardiac output (HR 0.42 [0.29, 0.59], P < 0.001) were associated with length of hospital stay.

Conclusions

Early recognition and management of hyponatremia, renal dysfunction, fluid retention, and hyperbilirubinemia may benefit constrictive pericarditis patients after pericardiectomy.

Sutureless and Rapid Deployment Versus Sutured Aortic Valve Replacement: a Propensity Matched Comparison from the Sutureless and Rapid Deployment International Registry

OBJECTIVE

To compare procedural and in-hospital outcomes of patients undergoing sutureless (Perceval, Livanova PLC, London, UK) and rapid deployment (Intuity Elite, Edwards Lifesciences, Irvine, USA) aortic valve replacement (group 1) versus sutured aortic valve replacement (group 2).

METHODS

Patients receiving isolated aortic valve replacement between 2014 and 2020 were analysed using data from the Sutureless and Rapid Deployment International Registry. Patients in group 1 and group 2 were propensity-score matched in a 1:1 ratio.

RESULTS

A total of 7708 patients were included in the study. After matching, 2 groups of 2643 each were created. Patients in group 1 were more likely to undergo minimally invasive approaches and were associated with shorter operative times when compared with group 2. Overall in-hospital mortality was similar between groups. While an increased risk of stroke was observed in group 1 in the first study period (2014-2016) (relative risk 3.76, p < 0.001), no difference was found in more recent year period (relative risk 1.66, p = 0.08)(p for heterogeneity 0.003). Group 1 was associated with reduced rates of postoperative low cardiac output syndrome, atrial fibrillation and mild aortic regurgitation. New pacemaker implant was three-fold higher in group 1.

CONCLUSIONS

Our findings showed significant differences in procedural and clinical outcomes between the study groups. These results suggest that sutureless and rapid deployment aortic valve replacement should be considered as part of a comprehensive valve program. The knowledge of the respective post-aortic valve replacement benefits for different valve technologies may result in patient-tailored valve selection with improved clinical outcomes.

Associated factors and clinical outcomes in mechanical circulatory support use in patients undergoing high risk on-pump cardiac surgery: Insights from the LEVO-CTS trial

BACKGROUND

We describe variables and outcomes associated with peri-operative mechanical circulatory support (MCS) utilization among patients enrolled in the Levosimendan in patients with Left Ventricular Systolic Dysfunction Undergoing Cardiac Surgery Requiring Cardiopulmonary Bypass (LEVO-CTS) trial.

METHODS

In the LEVO-CTS trial, MCS utilization (defined as intra-aortic balloon pump, extracorporeal membrane oxygenation, or surgical ventricular assist device) within 5 days of surgery was examined. The association between MCS use and outcomes including 90-day mortality, 30-day renal-replacement therapy, and hospital and critical stay length of stay were determined.

RESULTS

Among the 849 patients from 70 centers randomized to levosimendan or placebo, 85 (10.0%) patients were treated with MCS (71 intra-aortic balloon pump, 7 extracorporeal membrane oxygenation, 7 ventricular assist device); with 89.4% started on post-operative day 0. Inter-institutional use ranged from 0% to 100%. Variables independently associated with MCS utilization included combined coronary artery bypass grafting and valve surgery (adjusted odds ratio [OR] 2.73, 95% confidence interval [CI] 1.70-4.37, P < .001), history of lung disease (OR 1.70, 95% CI 1.06-2.70, P = .029), and history of heart failure (OR 2.44, 95% CI 1.10-5.45, P = .027). Adjusted 90-day mortality (22.4% vs 4.1%, hazard ratio 6.11, 95% CI 3.95-9.44, P < .001) was higher, and median critical care length of stay (8.0 vs 4.0 days, P < .001) was longer in patients managed with MCS.

CONCLUSIONS

In a randomized controlled trial of high-risk cardiac surgical patients in North America, we observed patient, and surgical variables associated with MCS utilization. MCS use was associated with a higher risk of post-operative mortality.

The evaluation of levosimendan in patients with acute myocardial infarction related ventricular septal rupture undergoing cardiac surgery: a prospective observational cohort study with propensity score analysis

STUDY OBJECTIVE

The purpose of the present study was to evaluate the efficacy of levosimendan in patients with acute myocardial infarction related ventricular septal rupture (AMI-VSR) underwent cardiac surgery.

DESIGN

Prospective observational cohort study with propensity score analysis.

PATIENTS

There were 261 patients with AMI-VSR in our study. After 1:1 propensity matching, 106 patients (53 levosimendan and 53 control) were selected in the matched cohort.

INTERVENTIONS

None.

MEASUREMENTS

Patients who received levosimendan were assigned to the levosimendan group (n = 164). The patients who were not received were levosimendan assigned to the control group (n = 97). The levosimendan was initiated immediately after cardiopulmonary bypass. Then, it has been maintained during the postoperative 3 days. The poor outcomes were identified as follows: death and postoperative complications (postoperative stroke, low cardiac output syndromeneeded mechanical circulatory support after surgery, acute kidney injury (≥ stage III), postoperative infection or septic shock, new developed atrial fibrillation or ventricular arrhythmias).

MAIN RESULTS

Before matching, the control group had more length of ICU stay (6.69 ± 3.90 d vs. 5.20 ± 2.24 d, p < 0.001) and longer mechanical ventilation time (23 h, IQR: 16-53 h vs. 16 h, IQR: 11-23 h, p < 0.001). Other postoperative outcomes have not shown significant differences between two groups. After matching, no significant difference was found between both groups for all postoperative outcomes. The Kaplan-Meier survivul estimate and log-rank test showed that the 90-day survival had no significant differences between two groups before and after matching.

CONCLUSION

Our study found that a low-dose infusion of levosimendan in AMI-VSR patients underwent surgical repair did not associated with positively affect to postoperative outcomes.

Pre-operative, Intraoperative, and Post-operative Determinants Associated with 30-day Mortality Post-Coronary Artery Bypass Graft: A Retrospective Cohort Study

Abstract Background: Various determinants of 30-day mortality risk in CABG patients have been formulated into certain scoring models such as the EuroSCORE and ACEF model. However, these models only consider preoperative parameters while excluding intraoperative, postoperative, and perioperative parameters. Currently, the prior research has increasingly emphasized the role of these excluded parameters as determinants of post-CABG mortality. Furthermore, there are differences in mortality rate of CABG procedures in Indonesia when compared with other countries. Hence, this study aimed to identify preoperative, intraoperative, and postoperative determinants of 30-day mortality after CABG surgery in Indonesian population. Methods: In this retrospective cohort study, secondary data were obtained from the medical records of 263 patients aged ≥ 18 years who underwent CABG at a single center in Indonesia during the year 2012–2015. Selected preoperative, intraoperative, postoperative, and perioperative determinants were analyzed in both bivariate and multivariate Cox regression models to identify determinants associated with 30-day mortality. Results: The 30-day mortality rate after CABG was 11.8%. Multivariate analysis identified neurological dysfunction (HR 6.16; 95% CI 2.42-15.66), renal impairment (HR 3.9; 95% CI 1.46-10.38), left ventricle dysfunction (HR 3.53;95% CI 1.55-8.03), aortic clamp duration (HR 3.7;95% CI 1.53-8.96), surgery duration (HR 3.85;95% CI 1.39-10.70), postoperative thrombocytopenia (HR 3.99;95% CI 1.72-9.23), and postoperative intra-aortic balloon pump (HR 10.98; 95% CI 4.77-25.28) as significant determinants associated with 30-day mortality after CABG Conclusions: Neurological dysfunction, renal impairment, left ventricle dysfunction, aortic clamp duration, surgery duration, postoperative thrombocytopenia, and postoperative intra-aortic balloon pump were independent determinants for 30-day mortality after CABG.

Association Between Hypernatremia and Delirium After Cardiac Surgery: A Nested Case-Control Study

Background

The association between hypernatremia and delirium after cardiac surgery has rarely been investigated. This study aimed to determine whether hypernatremia increases the risk of delirium after exposure.

Materials and Methods

From April 2016 to June 2021, 7,831 consecutive patients receiving cardiac surgery were screened for potential enrollment. The primary outcome was postoperative delirium (POD). For the respective case of delirium, 10 controls were matched according to the index date within the nested case-control design. Hypernatremia exposure was defined as serum sodium > 145 mmol/L within 7 days before the index date. A generalized estimation equation was performed to assess excess risks for POD associated with hypernatremia, adjusted for demographics and clinical variables.

Results

About 7,277 patients were included in the final analyses. About 669 (9.2%) patients with POD were assigned to the case group, and 6,690 controls were identified from the whole population. About 66.5% of the cases and 36.3% of the controls had hypernatremia exposure. After being adjusted to certain well-recognized confounding factors, hypernatremia showed a significant correlation with increased risk of delirium after cardiac surgery (adjusted OR, 1.73; 95% CI, 1.41~2.12). An e-value analysis suggested the robustness to unmeasured confounding.

Conclusions

Hypernatremia was associated with an increased risk of delirium after cardiac surgery. This finding could have implications for risk stratification, early detection, and management of delirium in patients receiving cardiac surgery.

Myocardial Protection With Different Cardioplegia in Adult Cardiac Surgery: A Network Meta-Analysis

AIM

Cardioplegia is one of the most studied fields of myocardial protection during cardiac surgery. However, the most effective cardioplegia for protection in adult cardiac surgery remains unknown.

METHOD

PubMed and other databases were searched and a network meta-analysis with a Bayesian framework was performed. The primary outcomes were the serum concentrations of creatine kinase-myocardial band (CK-MB), cardiac troponin I, and cardiac troponin T (cTnT) at four time points. Several clinical outcomes were evaluated, including low output syndrome, myocardial infarction, and risk of early mortality. All studies that involved crystalloid cardioplegia without reference to St Thomas cardioplegia or histidine-tryptophan-ketoglutarate solution, and if the cardioplegia was used at a temperature between 4°C and 16°C were classified as cold crystalloid (cCCP) or cold blood cBCP cardioplegia. Warm blood cardioplegia (wBCP) was defined as the blood cardioplegia used at a temperature between 32°C and 37°C.

RESULTS

Forty-seven (47) studies with a total of 4,175 patients were included. Seven (7) cardioplegia solutions were used, including cold CCP or BCP, del Nido solution, histidine-tryptophan-ketoglutarate solution, St Thomas cardioplegia, wBCP and warm terminal blood cardioplegia (wtBCP). The serum concentrations of CK-MB at 2 hours (mean difference [MD], 213.56; 95% confidence interval [CI], -25.79 to -1.59) and cTnT at 24 hours of wBCP (MD, -1.50; 95% CI, -2.69 to -0.31) were significantly lower than that of cCCP. There were no significant differences in other outcomes of these six cardioplegia solutions, when compared to cCCP.

CONCLUSIONS

The seven cardioplegia solutions analysed had similar myocardial protective effects after adult cardiac surgery, although wBCP had a lower CK-MB at 2 hours and lower cTnT at 24 hours.

Preoperative Combined Adiposity–Nutritional Index Predicts Major aDverse Cardiac and Cerebral Events following Off-pump coRonary Artery Revascularization (PANDORA): A Retrospective Single-Center Study

Background The metabolic–nutritional profile of coronary artery disease (CAD) patients can be an important outcome determinant. A high visceral adiposity index (VAI) and a low prognostic nutritional index (PNI) have been described to predict major adverse cardiac and cerebral events (MACCE) in nonoperative settings and poor cardiac-surgical outcomes, respectively. The present study evaluated the MACCE-predictive value of the two indices, in isolation and as a combined adiposity–nutritional index (CANI = VAI/PNI) in patients undergoing off-pump coronary artery bypass grafting (OPCABG).

Methods The retrospective study was conducted in 1207 OPCABG patients at a tertiary cardiac care center. Thirty-day postoperative data was evaluated for the development of MACCE, defined by any of the following: cardiac arrest, ST-segment elevation myocardial ischemia (STEMI), repeat coronary revascularization, or stroke. The perioperative characteristics of the MACCE and no-MACCE groups were analyzed for the predictors of postoperative MACCE.

Results One-hundred thirty-two patients (10.93%) developed MACCE postoperatively. On univariate analysis, age, EuroSCORE II, ejection fraction, diabetes mellitus, asymptomatic carotid artery disease, left main (LM) disease, PNI, and VAI predicted MACCE. Subsequent to multivariate analysis, age, EuroSCORE II, and CANI were the independent predictors. The MACCE predictive cutoffs of VAI, PNI, and CANI were 3.2, 38.46, and 0.075 (area under the curve [AUC]; sensitivity; specificity: 0.64; 77%; 81.3%, 0.77; 92.6%, 65%, 0.78; 64.5%; 80.2%, respectively). CANI correlated positively with duration of mechanical ventilation, length of intensive care unit (ICU) stay, and mean postoperative vasoactive inotropic scores (VIS). CANI ≥ 0.075 was also associated with a higher incidence of postoperative atrial fibrillation, low cardiac output syndrome, and acute kidney injury.

Conclusions CANI emerged as an independent predictor of MACCE following OPCABG.

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.

Heart Failure after Cardiac Surgery: The Role of Halogenated Agents, Myocardial Conditioning and Oxidative Stress

Heart disease requires a surgical approach sometimes. Cardiac-surgery patients develop heart failure associated with ischemia induced during extracorporeal circulation. This complication could be decreased with anesthetic drugs. The cardioprotective effects of halogenated agents are based on pre- and postconditioning (sevoflurane, desflurane, or isoflurane) compared to intravenous hypnotics (propofol). We tried to put light on the shadows walking through the line of the halogenated anesthetic drugs’ effects in several enzymatic routes and oxidative stress, waiting for the final results of the ACDHUVV-16 clinical trial regarding the genetic modulation of this kind of drugs.

Effect of Volatile Anesthetics on Myocardial Infarction After Coronary Artery Surgery: A Post Hoc Analysis of a Randomized Trial

OBJECTIVE

To investigate the effect of volatile anesthetics on the rates of postoperative myocardial infarction (MI) and cardiac death after coronary artery bypass graft (CABG).

DESIGN

A post hoc analysis of a randomized trial.

SETTING

Cardiac surgical operating rooms.

PARTICIPANTS

Patients undergoing elective, isolated CABG.

INTERVENTIONS

Patients were randomized to receive a volatile anesthetic (desflurane, isoflurane, or sevoflurane) or total intravenous anesthesia (TIVA). The primary outcome was hemodynamically relevant MI (MI requiring high-dose inotropic support or prolonged intensive care unit stay) occurring within 48 hours from surgery. The secondary outcome was 1-year death due to cardiac causes.

MEASUREMENTS AND MAIN RESULTS

A total of 5,400 patients were enrolled between April 2014 and September 2017 (2,709 patients randomized to the volatile anesthetics group and 2,691 to TIVA). The mean age was 62 ± 8.4 years, and the median baseline ejection fraction was 57% (50-67), without differences between the 2 groups. Patients in the volatile group had a lower incidence of MI with hemodynamic complications both in the per-protocol (14 of 2,530 [0.6%] v 27 of 2,501 [1.1%] in the TIVA group; p = 0.038) and as-treated analyses (16 of 2,708 [0.6%] v 29 of 2,617 [1.1%] in the TIVA group; p = 0.039), but not in the intention-to-treat analysis (17 of 2,663 [0.6%] v 28 of 2,667 [1.0%] in the TIVA group; p = 0.10). Overall, deaths due to cardiac causes were lower in the volatile group (23 of 2,685 [0.9%] v 40 of 2,668 [1.5%] than in the TIVA group; p = 0.03).

CONCLUSIONS

An anesthetic regimen, including volatile agents, may be associated with a lower rate of postoperative MI with hemodynamic complication in patients undergoing CABG. Furthermore, it may reduce long-term cardiac mortality.

Predictors of Low Cardiac Output Syndrome in Infants After Open-Heart Surgery

OBJECTIVE

To evaluate the predictors of low cardiac output syndrome (LCOS) in infants with congenital heart disease (CHD) after cardiopulmonary bypass (CPB).

STUDY DESIGN

A total of 217 infants were enrolled and classified according to whether they developed LCOS after cardiac surgery. Each infant's preoperative and intraoperative clinical variables were collected.

RESULTS

The incidence of LCOS was 28.11% in our study. The univariate analysis showed that the LCOS group was younger than the non-LCOS group (25.69 ± 25.01 days vs. 44.45 ± 26.97 days, P < 0.001), with a higher proportion of neonates (60.7 vs. 27.6%, P < 0.001) and a higher proportion of patients with a RACHS-1 score ≥4 (50.8 vs. 17.9%, P < 0.001). A lower weight (3.70 ± 0.74 vs. 4.23 ± 1.10 kg, P = 0.001), longer ACC time (61.96 ± 21.44 min vs. 41.06 ± 18.37 min, P < 0.001) and longer CPB time (131.54 ± 67.21 min vs. 95.78 ± 62.67 min, P < 0.001) were found in the LCOS group. The levels of free triiodothyronine (FT3) (4.55 ± 1.29 pmol/L vs. 5.18 ± 1.42 pmol/L, P = 0.003) and total triiodothyronine (TT3) (1.80 ± 0.56 nmol/L vs. 1.98 ± 0.54 nmol/L, P = 0.026) were also lower in the LCOS group. The multivariate binary logistic regression analysis and receiver operating characteristic (ROC) indicated that the ACC time, FT3 level and body weight were independent predictors of LCOS.

CONCLUSIONS

In our patient population, we first propose that preoperative FT3 can predict the occurrence of postoperative LCOS. ACC time, FT3 level and body weight are independent predictors of LCOS and maybe helpful in reducing the incidence of postoperative LCOS in the future.

Reliability of Bioreactance and Pulse-Power Analysis in Measuring Cardiac Index in Patients Undergoing Cardiac Surgery With Cardiopulmonary Bypass

OBJECTIVES

Less-invasive and continuous cardiac output monitors recently have been developed to monitor patient hemodynamics. The aim of this study was to compare the accuracy, precision, and trending ability of noninvasive bioreactance-based Starling SV and miniinvasive pulse-power device LiDCOrapid to bolus thermodilution technique with a pulmonary artery catheter (TDCO) when measuring cardiac index in the setting of cardiac surgery with cardiopulmonary bypass (CPB).

DESIGN

A prospective method-comparison study.

SETTING

Oulu University Hospital, Finland.

PARTICIPANTS

Twenty patients undergoing cardiac surgery with CPB.

INTERVENTIONS

Cardiac index measurements were obtained simultaneously with TDCO intraoperatively and postoperatively, resulting in 498 measurements with Starling SV and 444 with LiDCOrapid.

MEASUREMENTS AND MAIN RESULTS

The authors used the Bland-Altman method to investigate the agreement between the devices and four-quadrant plots with error grids to assess the trending ability. The agreement between TDCO and Starling SV was qualified with a bias of 0.43 L/min/m² (95% confidence interval [CI], 0.37-0.50), wide limits of agreement (LOA, -1.07 to 1.94 L/min/m²), and a percentage error (PE) of 66.3%. The agreement between TDCO and LiDCOrapid was qualified, with a bias of 0.22 L/min/m² (95% CI 0.16-0.27), wide LOA (-0.93 to 1.43), and a PE of 53.2%. With both devices, trending ability was insufficient.

CONCLUSION

The reliability of bioreactance-based Starling SV and pulse-power analyzer LiDCOrapid was not interchangeable with TDCO, thus limiting their usefulness in cardiac surgery with CPB.

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.

Managing patients of shock and acute kidney injury in tertiary care cardiac ICU: Experience with continuous renal replacement therapy

Background

Clinical experience on details of CRRT initiation and outcomes in cardiac intensive care unit (CICU) patients is not available from developing countries like India. This study shares the 5-year clinical experience of managing CICU patients requiring CRRT in a tertiary care cardiac center of North India.

Materials and methods

Medical records of all CICU patients with acute kidney injury (AKI) managed by CRRT from October 2011 to September 2016 at tertiary referral center in North India were retrospectively reviewed. Multiple logistic regression analysis was used to identify predictors of post-CRRT mortality.

Results

A total of 630 patients received CRRT during the study period. Most commonly AKI developed in patients with acute coronary syndrome (30.2 %) with cardiogenic shock. 55.9 % of the CRRT patients were >60 years of age, and/or on multiple supports in ICU including, mechanical ventilation, high doses of inotropes & vasopressors and other cardiovascular support. Of those on CRRT, 130 (20.6 %) patients had died, 215 (34.1 %) were discharged and 285 (45.2 %) could not complete the desired course. Multivariate regression analysis showed independent association of mortality with high vasoactive-inotropic score, single CRRT cycle and low mean arterial pressure in CRRT patients.

Conclusion

About 34.1 % of patients receiving CRRT were alive at discharge, emphasizing the feasibility and utility of CRRT as a promising modality in this population for improving outcomes.

Endo-Aortic vs. Trans-Thoracic Clamping in Right Mini-Thoracotomy Mitral Valve Surgery: Outcome on Myocardial Protection

Background: Perfusion strategies and aortic clamping techniques for right mini-thoracotomy mitral valve (MV) surgery have evolved over time and remarkable short- and long-term results have been reported. However, some concerns have raised about the adequacy of myocardial protection during the minimally invasive approach, particularly with the endo-aortic clamp (EAC). Aim of this study was to compare the efficacy, in terms of myocardial preservation, of the EAC with the trans-thoracic aortic clamp (TTC) in patients undergoing right mini-thoracotomy MV surgery. Methods: A single center, prospective observational study was performed on patients undergoing right mini-thoracotomy MV surgery with retrograde arterial perfusion and EAC or TTC. A propensity matched analysis was performed to compare the two groups. Primary outcome was the comparison between cardiac troponin T levels measured at different time-points after surgery. Results: Eighty EAC patients were compared with 37 TTC patients. No cases of myocardial infarction or low cardiac-output syndrome were overall reported. No differences were recorded in terms of stroke, peri-operative mortality, and in the release of myocardial markers, lactates levels and need for inotropic support at different time-points after surgery. CK-MB peak levels were significantly lower in the EAC group. Conclusion: Despite concerns arising about the EAC, this prospective study shows equivalence in terms of myocardial preservation of the EAC compared with the TTC in patients undergoing right mini-thoracotomy MV surgery.

Calcium administration In patients undergoing CardiAc suRgery under cardiopulmonary bypasS (ICARUS trial): Rationale and design of a randomized controlled trial

Introduction

Weaning from cardiopulmonary bypass (CPB) is a critical step of any cardiac surgical procedure and often requires pharmacologic intervention. Calcium ions are pivotal elements for the excitation-contraction coupling process of cardiac myocytes. Thus, calcium administration might be helpful during weaning from CPB.

Methods

We describe a multicenter, placebo-controlled, double blind randomized clinical trial to assess the effect of calcium chloride on the need for inotropic support among adult patients during weaning from CPB. The experimental group (409 patients) will receive 15 mg/kg of calcium chloride. The control group (409 patients) will receive an equivalent volume of 0.9% sodium chloride. Both drugs will be administered intravenously as a bolus at the beginning of weaning from CPB.

Results

The primary outcome will be the need for inotropic support between termination of CPB and completion of surgery. Secondary outcomes will be: duration of inotropic support, vasoactive-inotropic score 30 min after transfer to intensive care unit and on postoperative day 1, plasma alpha-amylase on postoperative day 1, plasma Ca²⁺ concentration immediately before and 10–15 min after calcium chloride administration, non-fatal myocardial infarction, blood loss on postoperative day 1, need for transfusion of red blood cells, signs of myocardial ischemia on electrocardiogram after arrival to intensive care unit, all-cause mortality at 30 days or during hospital stay if this is longer than 30 days.

Discussion

This trial is designed to assess whether intravenous calcium chloride administration could reduce the need for inotropic support after cardiopulmonary bypass weaning among adults undergoing cardiac surgery.

Association Between Sarcopenia and Adverse Events Following Transcatheter Aortic Valve Implantation

Background

Sarcopenia, the age-related loss of skeletal muscle mass/function, has been identified as a marker of frailty. We examined the association between sarcopenia and adverse events following transcatheter aortic valve implantation (TAVI).

Methods

A retrospective cohort study was conducted at Toronto General Hospital. All patients who underwent TAVI in the time period 2007-2017 with preoperative computed tomography were included. Skeletal muscle index (SMI) was calculated radiographically using psoas muscle area at the L3 vertebral level, divided by height. Various measures of sarcopenia, including mean SMI, SMI below the sex-specific median, and SMI in the lowest sex-specific quartile were calculated. The primary outcome was postoperative adverse events, defined as a composite of in-hospital mortality and morbidity including cardiovascular, pulmonary, neurologic, access-related, and gastrointestinal complications. Univariate and multivariate logistic regression were performed to determine the association between sarcopenia and adverse events.

Results

A total of 468 patients (mean age: 80.7 years) were included. Baseline comorbidity burden was high, particularly congestive heart failure (93.4%). Postoperative adverse events occurred in 62 patients (13.2%). Univariate logistic regression demonstrated that postoperative adverse events were correlated with mean SMI (odds ratio [OR] 0.81, 95% confidence interal [CI] 0.66-0.97), events were less than the SMI (OR 2.16, 95% CI 1.24-3.84), and SMI in the sex-specific lowest quartile (OR 2.34, 95% CI 1.33-4.07). On multivariate analysis, SMI in the sex-specific lowest quartile was an independent predictor of adverse events (OR 2.53, 95% CI 1.41-4.50).

Conclusions

Sarcopenia defined by radiologic psoas muscle measurements was independently associated with in-hospital mortality and morbidity following TAVI.

Cardiopulmonary Bypass-Induced Inflammation and Myocardial Ischemia and Reperfusion Injury Stimulates Accumulation of Soluble MER

OBJECTIVES

Soluble MER has emerged as a potential biomarker for delayed resolution of inflammation after myocardial injury and a therapeutic target to reduce cardiac-related morbidity and mortality in adults. The significance of soluble MER in pediatric populations, however, is unclear. We sought to investigate if soluble MER concentrations change in response to myocardial ischemia and reperfusion injury in pediatric patients. In parallel, we also sought to investigate for correlations between the change in soluble MER concentration and specific patient, bypass, and postoperative data.

DESIGN

We quantified the change in plasma soluble MER concentration post- compared with precardiopulmonary bypass for each patient in a cohort of pediatric patients. Linear regression, correlation coefficients, and t tests were used to compare innate patient characteristics (i.e., sex, age, cyanotic vs acyanotic cardiac lesion), cardiac bypass data (i.e., total cardiac bypass time, total aortic cross-clamp time, perioperative steroid administration), and postcardiac bypass data (total postoperative ventilator days, total postoperative vasoactive medication days, and total postoperative ICU days) with change in soluble MER concentrations.

SETTING

Whole blood samples were obtained intraoperatively at a single tertiary care children's hospital from April to October 2019.

SUBJECTS

Our patient cohort included 24 pediatric patients ages ranging from birth to 19 years old with both cyanotic and acyanotic cardiac lesions.

INTERVENTIONS

Retrospective analyses of pediatric blood specimens, as well as patient, bypass, and postoperative data, were performed.

MEASUREMENTS AND MAIN RESULTS

We observed a statistically significant increase in soluble MER concentration post cardiac bypass in 17 of 24 patients (71%).

CONCLUSIONS

Soluble MER concentrations increase with cardiopulmonary bypass-induced inflammation and myocardial ischemia and reperfusion injury in pediatric patients. The utility of soluble MER as a clinical biomarker to identify pediatric patients at risk for exacerbated postoperative outcomes after bypass-induced myocardial ischemia and reperfusion injury requires further investigation.

Efficacy of Whole-Blood Del Nido Cardioplegia Compared with Diluted Del Nido Cardioplegia in Coronary Artery Bypass Grafting: A Retrospective Monocentric Analysis of Pakistan

Background and Objectives: Cardioplegia is one of the most significant components used to protect the myocardium during cardiac surgery. There is a paucity of evidence regarding the utilization of whole-blood Del Nido cardioplegia (WB-DNC) on clinical outcomes in coronary artery bypass grafting (CABG). The purpose of this retrospective cross-sectional study is to compare the effectiveness of diluted (blood to crystalloid; 1:4) Del Nido cardioplegia (DNC) with WB-DNC in patients who underwent elective CABG in a tertiary care hospital in Lahore-Pakistan. Materials and Methods: This was a retrospective descriptive study conducted at the Department of Cardiovascular Surgery, King Edward Medical University, Lahore. The medical database of all consecutive patients admitted from January 2018 to March 2020 and who fulfilled the inclusion criteria were reviewed. Results: Out of 471 patients admitted during the study period, 450 underwent various elective cardiac surgeries. Out of 450, 321 patients (71.33%) were operated on for CABG. Only 234/321 (72.89%) CABG patients fulfilled our inclusion criteria; 120 (51.28%) patients received WB-DNC, while 114 (48.71%) patients were administered with DNC. The former group presented with better clinical outcomes compared with the latter in terms of lesser requirements of inotropic support, low degree of hemodilution, shorter in-hospital stay, improved renal function, and cost-effectiveness. Peak values of serum Troponin-T (Trop-T), creatine kinase-myocardial band (CK-MB) release, and activated clotting time (ACT) were also lower in the WB-DNC group compared with the DNC group. Conclusions: The WB-DNC conferred better myocardial protection, improved early clinical outcomes, and also proved to be economical for patients undergoing elective CABG compared with classical crystalloid cardioplegia solution.

Assessment and Prognosis in CSA-AKI Using Novel Kidney Injury Biomarkers: A Prospective Observational Study

BACKGROUND

There is a need for early diagnostic solutions for cardiac surgery associated acute kidney injury (CSA-AKI) as serum creatinine changes do not occur dynamically enough. Moreover, new approaches are needed for kidney protective strategy in patients undergoing cardiac surgery procedures; Methods: Samples of serum and urine were taken from the selected group of patients undergoing elective cardiac surgery procedures. The aim of this study was to assess the utility of specific inflammation and kidney injury biomarkers in the early diagnostic of CSA-AKI and in the prognosis of long-term postoperative kidney function; Results: At 6 h after weaning from cardiopulmonary bypass, there were significant differences in IL-6, IL-8, TNF-α, MMP-9 and NGAL concentrations in patients with CSA-AKI, compared to the control group. Serum IL-8 and urine NGAL 6 h after weaning from CPB proved to be independent acute kidney injury predictors. The TNF-α, MMP-9, IL-18, TIMP-1 and MMP-9/TIMP-1 ratio in the early postoperative period correlated with long-term kidney function impairment; Conclusions: Novel kidney injury biomarkers are an eligible tool for early diagnosis of CSA-AKI. They are also reliable indicators of long-term postoperative kidney function impairment risk after cardiac surgery procedures.

A Randomized Porcine Study in Low Cardiac Output of Vasoactive and Inotropic Drug Effects on the Gastrointestinal Tract

BACKGROUND

Splanchnic vasodilation by inodilators is an argument for their use in critical cardiac dysfunction. To isolate peripheral vasoactivity from inotropy, such drugs were investigated, and contrasted to vasopressors, in a fixed low cardiac output (CO) model resembling acute cardiac dysfunction effects on the gastrointestinal tract. We hypothesized that inodilators would vasodilate and preserve the aerobic metabolism in the splanchnic circulation in low CO.

METHODS

In anesthetized pigs, CO was lowered to 60% of baseline by partial inferior caval vein balloon inflation. The animals were randomized to placebo (n = 8), levosimendan (24 μg kg-1 bolus, 0.2 μg kg-1 min-1, n = 7), milrinone (50 μg kg-1 bolus, 0.5 μg kg-1 min-1, n = 7), vasopressin (0.001, 0.002 and 0.006 U kg-1 min-1, 1 h each, n = 7) or norepinephrine (0.04, 0.12, and 0.36 μg kg-1 min-1, 1 h each, n = 7). Hemodynamic variables including mesenteric blood flow were collected. Systemic, mixed-venous, mesenteric-venous, and intraperitoneal metabolites were analyzed.

RESULTS

Cardiac output was stable at 60% in all groups, which resulted in systemic hypotension, low superior mesenteric artery blood flow, lactic acidosis, and increased intraperitoneal concentrations of lactate. Levosimendan and milrinone did not change any circulatory variables, but levosimendan increased blood lactate concentrations. Vasopressin and norepinephrine increased systemic and mesenteric vascular resistances at the highest dose. Vasopressin increased mesenteric resistance more than systemic, and the intraperitoneal lactate concentration and lactate/pyruvate ratio.

CONCLUSION

Splanchnic vasodilation by levosimendan and milrinone may be negligible in low CO, thus rejecting the hypothesis. High-dose vasopressors may have side effects in the splanchnic circulation.

Use of Vasoactive Medications after Cardiac Surgery in the United States

Rationale: Patients undergoing cardiac surgery often require vasopressor or inotropic ("vasoactive") medications, but patterns of postoperative use are not well described.Objectives: This study aimed to describe vasoactive medication administration throughout hospitalization for cardiac surgery, to identify patient- and hospital-level factors associated with postoperative use, and to quantify variation in treatment patterns among hospitals.Methods: Retrospective study using the Premier Healthcare Database. The cohort included adult patients who underwent coronary artery bypass grafting or open valve repair or replacement (or in combination) from January 1, 2016, to June 30, 2018. Primary outcome was receipt of vasoactive medication(s) on the first postoperative day (POD1). We identified patient- and hospital-level factors associated with receipt of vasoactive medications using multilevel mixed-effects logistic regression modeling. We calculated adjusted median odds ratios to determine the extent to which receipt of vasoactive medications on POD1 was determined by each hospital, then calculated quotients of Akaike Information Criteria to compare the relative contributions of patient and hospital characteristics and individual hospitals with observed variation.Results: Among 104,963 adults in 294 hospitals, 95,992 (92.2%) received vasoactive medication(s) during hospitalization; 30,851 (29.7%) received treatment on POD1, most commonly norepinephrine (n = 11,427, 37.0%). A median of 29.0% (range, 0.0-94.4%) of patients in each hospital received vasoactive drug(s) on POD1. After adjustment, hospital of admission was associated with twofold increased odds of receipt of any vasoactive medication on POD1 (adjusted median odds ratio, 2.07; 95% confidence interval, 1.93-2.21). Admitting hospital contributed more to observed variation in POD1 vasoactive medication use than patient or hospital characteristics (quotients of Akaike Information Criteria 0.58, 0.44, and <0.001, respectively).Conclusions: Nearly all cardiac surgical patients receive vasoactive medications during hospitalization; however, only one-third receive treatment on POD1, with significant variability by institution. Further research is needed to understand the causes of variability across hospitals and whether these differences are associated with outcomes.

Diagnostic accuracy of stroke volume variation for predicting fluid responsiveness in children undergoing cardiac surgery: A systematic review and meta-analysis

BACKGROUND

Stroke volume variation appears to be reliable for predicting fluid responsiveness in adults, and its predictive value in pediatric patients has been recently reported. However, its predictive value in children undergoing cardiac surgery is unclear.

METHODS

A review and meta-analysis were performed on the diagnostic utility of stroke volume variation for predicting fluid responsiveness in children undergoing cardiac surgery. All relevant articles for prospective research assessing the value of stroke volume variation were searched in the Embase, MEDLINE (PubMed), and Cochrane databases through March 2020. The primary outcome was the accuracy of stroke volume variation for predicting fluid responsiveness in children. The combined data were analyzed by a meta-analysis. Publication quality was assessed using the QUADAS (quality assessment for studies of diagnostic accuracy, maximum score) standard guidelines.

RESULTS

Six articles were included in the meta-analysis, following the search strategy. A total of 251 children were included from 6 prospective studies. Fluid therapy for all patients used crystalloids or colloids. The results of the analysis revealed a pooled diagnostic odds ratio of 8.23 (95% CI: 3.07-22.11), pooled sensitivity of 0.73 (95% CI: 0.64-0.80), and pooled specificity of 0.66 (95% CI: 0.58-0.74). Additionally, the overall area of the summary receiver operating characteristic curve was 0.78. There was significant moderate heterogeneity in these studies (p < .05, I²  = 42.1%) due to thresholds.

CONCLUSIONS

There was some heterogeneity due to thresholds in the included studies. An evaluation of stroke volume variation may represent a reliable predictor of fluid responsiveness in children undergoing cardiac surgery. After operative cardiac output optimization, the possible impact of goal-directed fluid treatment depending on stroke volume variation on the perioperative outcome in the children population should subsequently be assessed.

[Cardiac arrest under special circumstances]

These guidelines of the European Resuscitation Council (ERC) Cardiac Arrest under Special Circumstances are based on the 2020 International Consensus on Cardiopulmonary Resuscitation Science with Treatment Recommendations. This section provides guidelines on the modifications required for basic and advanced life support for the prevention and treatment of cardiac arrest under special circumstances; in particular, specific causes (hypoxia, trauma, anaphylaxis, sepsis, hypo-/hyperkalaemia and other electrolyte disorders, hypothermia, avalanche, hyperthermia and malignant hyperthermia, pulmonary embolism, coronary thrombosis, cardiac tamponade, tension pneumothorax, toxic agents), specific settings (operating room, cardiac surgery, cardiac catheterization laboratory, dialysis unit, dental clinics, transportation [in-flight, cruise ships], sport, drowning, mass casualty incidents), and specific patient groups (asthma and chronic obstructive pulmonary disease, neurological disease, morbid obesity, pregnancy).

Risk factors for vasoplegia after coronary artery bypass and valve surgery

INTRODUCTION

Vasoplegia denotes a state of low tissue perfusion characterized by hypotension, tachycardia, and low systemic vascular resistance. This state results in increased mortality and morbidity following cardiac surgery. A better understanding of the associated risk factors will guide the surgical team in patient management. The aim of this study is to determine which risk factors are involved in its emergence.

METHODS

This prospective observational study included adult cardiac surgery patients between February - September 2018 at a single cardiothoracic surgery center. Patients were evaluated for cardiac contractility, surgical drainage, inotrope, and vasopressor requirement perioperatively. The groups were compared for demographic, echocardiographic, and operative variables. Variables significant in univariate analysis were carried on to binary logistic regression for risk factor analysis.

RESULTS

A total of 31 patients were vasoplegic among a total of 487 included patients, resulting in a 6.37% incidence. In the vasoplegia group, chronic kidney failure, use of angiotensin-converting enzyme (ACE) inhibitors, use of angiotensin receptor blockers, and use of diuretics were more frequent, cardiopulmonary bypass (CPB) and aortic cross-clamp durations were longer, and mean Euroscore II was higher. Vasoplegia was more frequent in valve surgery and resternotomy patients. CPB duration, use of ACE inhibitors, use of angiotensin receptor blockers, and chronic renal failure were independent risk factors.

CONCLUSION

Patients with long CPB duration, preoperative use of ACE inhibitors or Angiotensin receptor blockers, and a history of renal failure requiring dialysis are under increased risk of vasoplegia. Vasoplegia necessitates large-scale studies for a better understanding of its risk factors.

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.