Causes of death after congenital heart surgery

L-carnitine decreases myocardial injury in children undergoing open-heart surgery: A randomized controlled trial

Myocardial injury in open-heart surgery is related to several factors including ischemia-reperfusion injury, generation of reactive oxygen species, increased production of inflammatory mediators, and enhancement of apoptosis of cardiomyocytes. The aim of this study was to study the effect of L-carnitine on myocardial injury in children undergoing open-heart surgery. This clinical trial was performed on 60 children with congenital heart disease (CHD) who underwent open-heart surgery. They were randomized into two groups: L-carnitine group who received L-carnitine 50 mg\kg\day once daily for 1 month before cardiac surgery and control group who received placebo for 1 month before cardiac surgery. Left ventricular cardiac function was assessed by conventional echocardiography to measure left ventricular ejection fraction (LVEF) and two-dimensional speckle tracking echocardiography (2D-STE) to determine left ventricular global longitudinal strain (2D-LV GLS). Blood samples were obtained pre-operatively at baseline before the administration of L-carnitine or placebo and 12 h post-operatively to measure the level of malondialdehyde (MDA), superoxide dismutase (SOD), fas, caspase-3, creatinine kinase-MB (CK-MB), and troponin I. L-carnitine group had significantly lower post-operative level of oxidative stress marker (MDA), apoptosis markers (fas and caspase-3), and myocardial injury markers (CK-MB and troponin I), but they had significantly higher SOD post-operative level compared to the control group. In addition, post-operative LVEF and 2D-LVGLS were significantly lower in the control group compared to L-carnitine group.   Conclusion: L-carnitine can reduce myocardial injury, improve post-operative left ventricular cardiac function, and may provide myocardium protection in children with CHD who underwent open-heart surgery.   Trial registration: The clinical trial was registered at www.pactr.org with registration number PACTR202010570607420 at 29/10/2020 before recruiting the patients. What is Known: • Myocardial injury in open-heart surgery is related to several factors including ischemia-reperfusion injury, generation of reactive oxygen species, increased production of inflammatory mediators, and enhancement of apoptosis of cardiomyocytes. • L-carnitine was reported to have myocardial protective effects in rheumatic valvular surgery and coronary artery bypass graft (CABG) in adults; however, there is no evidence on its effectiveness in children undergoing open-heart surgery. What is New: • L-carnitine significantly lowered the post-operative level of oxidative stress marker (MDA), apoptosis markers (fas and caspase-3), and myocardial injury markers (CK-MB and troponin I) in the treatment group. • L-carnitine can reduce myocardial injury, improve post-operative left ventricular cardiac function, and may provide myocardium protection in children with CHD who underwent open-heart surgery.

Congenital heart diseases (CHDs) and forensic investigations: Searching for the cause of death

Congenital Heart Diseases (CHDs) are a group of structural abnormalities or defects of the heart that are present at birth. CHDs could be connected to sudden death (SD), defined by the WHO (World Health Organization) as "death occurring within 24 h after the onset of the symptoms" in an apparently "healthy" subject. These conditions can range from relatively mild defects to severe, life-threatening anomalies. The prevalence of CHDs varies across populations, but they affect millions of individuals worldwide. This article aims to discuss the post-mortem investigation of death related to CHDs, exploring the forensic approach, current methodologies, challenges, and potential advancements in this challenging field. A further goal of this article is to provide a guide for understanding these complex diseases, highlighting the pivotal role of autopsy, histopathology, and genetic investigations in defining the cause of death, and providing evidence about the translational use of autopsy reports. Forensic investigations play a crucial role in understanding the complexities of CHDs and determining the cause of death accurately. Through collaboration between medical professionals and forensic experts, meticulous examinations, and analysis of evidence, valuable insights can be gained. These insights not only provide closure to the families affected but also contribute to the prevention of future tragedies.

Bilateral remote ischemic conditioning in children: A two-center, double-blind, randomized controlled trial in young children undergoing cardiac surgery

Objective

The study objective was to determine whether adequately delivered bilateral remote ischemic preconditioning is cardioprotective in young children undergoing surgery for 2 common congenital heart defects with or without cyanosis.

Methods

We performed a prospective, double-blind, randomized controlled trial at 2 centers in the United Kingdom. Children aged 3 to 36 months undergoing tetralogy of Fallot repair or ventricular septal defect closure were randomized 1:1 to receive bilateral preconditioning or sham intervention. Participants were followed up until hospital discharge or 30 days. The primary outcome was area under the curve for high-sensitivity troponin-T in the first 24 hours after surgery, analyzed by intention-to-treat. Right atrial biopsies were obtained in selected participants.

Results

Between October 2016 and December 2020, 120 eligible children were randomized to receive bilateral preconditioning (n = 60) or sham intervention (n = 60). The primary outcome, area under the curve for high-sensitivity troponin-T, was higher in the preconditioning group (mean: 70.0 ± 50.9 μg/L/h, n = 56) than in controls (mean: 55.6 ± 30.1 μg/L/h, n = 58) (mean difference, 13.2 μg/L/h; 95% CI, 0.5-25.8; P = .04). Subgroup analyses did not show a differential treatment effect by oxygen saturations (pinteraction = .25), but there was evidence of a differential effect by underlying defect (pinteraction = .04). Secondary outcomes and myocardial metabolism, quantified in atrial biopsies, were not different between randomized groups.

Conclusions

Bilateral remote ischemic preconditioning does not attenuate myocardial injury in children undergoing surgical repair for congenital heart defects, and there was evidence of potential harm in unstented tetralogy of Fallot. The routine use of remote ischemic preconditioning cannot be recommended for myocardial protection during pediatric cardiac surgery.

Prophylactic use of levosimendan in preoperative setting for surgical repair of congenital heart disease in children

Introduction

Low cardiac output syndrome (LCOS) is a significant cause of morbidity and the leading cause of mortality after pediatric cardiac surgery. Levosimendan has been shown safe and effective in pediatrics to treat LCOS. We aimed to review our local strategy with preoperative prophylactic Levosimendan infusion to minimize LCOS after heart surgery in identified high-risk patients.

Methods

Retrospective monocentric study. As there is no reliable cardiac output measurement in children, we recorded hemodynamic parameters as surrogates of cardiac output after extracorporeal circulation through an electronic patient survey system at different time points.

Results

Seventy-two children received Levosimendan before surgery between 2010 and 2019. As expected, most patients were newborns and infants with prolonged open-heart surgeries. Median cardiopulmonary bypass time was 182 [137-234] min, and aortic clamping time was 95 [64-126] min. The postoperative hemodynamic parameters, vasoactive-inotropic score, and urine output remained stable throughout the first 48 h. Only a tiny portion of the patients had combined surrogate markers of LCOS with a maximal median arterial lactate of 2.6 [1.9-3.5] mmol/L during the first six postoperative hours, which then progressively normalized. The median arterio-venous difference in oxygen saturation was 31 [23-38] % between 12 and 18 h post-surgery and gradually decreased. The median venous-to-arterial CO2 difference was the highest at 10 [7-12] mmHg between 12 and 18 h post-surgery. Nine patients (13%) required extracorporeal membrane oxygenation. No patient required dialysis or hemofiltration. Mortality was 0%.

Conclusion

Before congenital heart surgery, preoperative prophylactic administration of Levosimendan seems effective and safe for decreasing occurrence and duration of LCOS in high-risk children.

The cardioprotective and anti-inflammatory effect of inhaled nitric oxide during Fontan surgery in patients with single ventricle congenital heart defects: a prospective randomized study

Background

Fontan surgery with cardiopulmonary bypass (CPB) causes tremendous systemic stress and inflammatory responses, affecting postoperative organ function, morbidity, and mortality. Although this reaction triggers partially protective anti-inflammatory responses, it is harmful in patients with single ventricle congenital heart defects. Despite decades of research, an effective anti-inflammatory and stress defense strategy is lacking. This study investigated the influence of inhaled nitric oxide (NO) during CPB on early clinical results, including the duration of postoperative respiratory support as a primary outcome and a panel of laboratory analytes.

Methods

In this study, 115 patients were randomized to the Fontan-NO group (n = 48) and the Fontan group (n = 49). Eighteen patients were excluded from the study. The Fontan-NO group received NO inhaled directly into the oxygenator during CPB. Clinical data were collected, and blood samples were drawn for analysis at repeated intervals. Multiplex assays were used to analyze a proteome profile of molecules involved in stress response, inflammation, metabolic reactions, as well as heart and lung protection.

Results

Fontan-NO patients had significantly shorter respiratory support time with a median of 9.3 h (7.0; 13,2) vs 13.9 h (3.7; 18.5) by the absolute difference of 4.6 h [95% confidence interval, − 30.9 to 12.3; (p = 0.03)]. In addition, they have a shorter time in intensive care (p = 0.04) and lower pulmonary artery pressure after CPB discontinuation (p = 0.04), 4 h (p = 0.03) and 8 h (p = 0.03) after surgery. Fontan-NO patients also had a lower concentration of lactates (p = 0.04) and glucose after separation from CPB (p = 0.02) and lower catecholamine index (p = 0.042). Plasma factors analysis has shown a significantly higher concentration of interleukin-10, and a lower concentration of interleukin-6, interleukin-8, interleukin-1β, pentraxin, matrix metalloproteinase-8, troponin-I, creatine kinase myocardial band (CK-MB), and insulin in Fontan-NO group.

Conclusions

NO inhaled into the oxygenator during CPB can improve short-term clinical outcomes. It shortens intubation time and intensive care time. It reduces inflammatory response, improves myocardial and lung protection, and diminishes metabolic stress in patients with a single ventricle undergoing Fontan surgery.

Trial registration number: The trial was preregistered, supervised, and supported by The Polish National Science Center (NCN/01/B/NZ5/04246).

Supplementary Information

The online version contains supplementary material available at 10.1186/s40560-022-00639-y.

Wearable Seismocardiography‐Based Assessment of Stroke Volume in Congenital Heart Disease

Background

Patients with congenital heart disease (CHD) are at risk for the development of low cardiac output and other physiologic derangements, which could be detected early through continuous stroke volume (SV) measurement. Unfortunately, existing SV measurement methods are limited in the clinic because of their invasiveness (eg, thermodilution), location (eg, cardiac magnetic resonance imaging), or unreliability (eg, bioimpedance). Multimodal wearable sensing, leveraging the seismocardiogram, a sternal vibration signal associated with cardiomechanical activity, offers a means to monitoring SV conveniently, affordably, and continuously. However, it has not been evaluated in a population with significant anatomical and physiological differences (ie, children with CHD) or compared against a true gold standard (ie, cardiac magnetic resonance). Here, we present the feasibility of wearable estimation of SV in a diverse CHD population (N=45 patients).

Methods and Results

We used our chest‐worn wearable biosensor to measure baseline ECG and seismocardiogram signals from patients with CHD before and after their routine cardiovascular magnetic resonance imaging, and derived features from the measured signals, predominantly systolic time intervals, to estimate SV using ridge regression. Wearable signal features achieved acceptable SV estimation (28% error with respect to cardiovascular magnetic resonance imaging) in a held‐out test set, per cardiac output measurement guidelines, with a root‐mean‐square error of 11.48 mL and R 2 of 0.76. Additionally, we observed that using a combination of electrical and cardiomechanical features surpassed the performance of either modality alone.

Conclusions

A convenient wearable biosensor that estimates SV enables remote monitoring of cardiac function and may potentially help identify decompensation in patients with CHD.

Non-invasive cardiac output monitoring with electrical velocimetry after cardiac surgery in infants

INTRODUCTION

Low cardiac output following cardiac surgery is a major determinant of outcome that may be improved by early detection, yet there are no widely accepted methods for its measurement in young children. We evaluated the feasibility of the routine use of electrical velocimetry, a non-invasive technique providing continuous measurement of cardiac output, in infants in the early postoperative period.

METHODS

With ethical approval and parental consent, infants undergoing cardiac surgery were recruited. The ICON electrical velocimetry monitor was attached on admission to the intensive care unit (ICU) and remained for up to 24h.

RESULTS

A total of 15 infants were recruited, median age 3 months (interquartile range (IQR) 0.5-7.5) and weight 4.8kg (IQR 3.9-7.1), undergoing various operations. Cardiac index had a weak correlation with arterial lactate (r=-0.24, p=0.02) and no correlation with blood pressure, central venous pressure or arteriovenous oxygen difference. Data were recorded for a median of 19h (range 5-24), with lead detachment or movement artefact the most common causes of data loss. There was marked minute-to-minute variability, with 25% of consecutive measurements having >5% variability.

CONCLUSION

Cardiac index measured by electrical velocimetry in infants in the early postoperative period is impaired by frequent data loss and marked intrapatient variability. Our feasibility study suggests that it is unsuitable for use as a routine monitoring tool in the setting of postsurgical ICU care.

The number of postoperative surgical or diagnostic procedures following congenital heart surgery correlates with both mortality and hospital length of stay

BACKGROUND

Outcomes for congenital heart disease have dramatically improved over the past several decades. However, there are patients who encounter intraoperative or postoperative complications and ultimately do not survive. It was our hypothesis that the number of postoperative procedures (including surgical and unplanned diagnostic procedures) would correlate with hospital length of stay and operative mortality.

METHODS

This was a retrospective review of 938 consecutive patients undergoing congenital heart surgery at a single institution over a 2-year timeframe. The number of postoperative surgical and unplanned diagnostic procedures were counted and the impact on hospital length of stay and mortality was assessed.

RESULTS

581 of the 938 (62%) patients had zero postoperative diagnostic or surgical procedures. These patients had a median length of stay of 6 days with a single operative mortality (0.2%). 357 of the 938 (38%) patients had one or more postoperative diagnostic or surgical procedures. These patients had a total of 1586 postoperative procedures. There was a significant correlation between the number of postoperative procedures and both hospital length of stay and mortality (p < .001). Patients who required 10 or more postoperative procedures had a median hospital length of stay of 89 days and had a 50% mortality. There were no survivors in patients who had 15 or more postoperative procedures.

CONCLUSIONS

The data demonstrate that the number of postoperative procedures was highly correlated with both hospital length of stay and mortality.

Long-Term Outcomes of Patients Requiring Unplanned Repeated Interventions After Surgery for Congenital Heart Disease

BACKGROUND

Unplanned catheter-based or surgical reinterventions after congenital heart operations are independently associated with operative mortality and increased postoperative length of stay.

OBJECTIVES

This study assessed the long-term outcomes of transplant-free survivors of hospital discharge requiring predischarge reinterventions after congenital cardiac surgery.

METHODS

Data from patients who required predischarge reinterventions in the anatomic area of repair after congenital cardiac surgery and survived to hospital discharge at a quaternary referral center from January 2011 to December 2019 were retrospectively reviewed. Previously published echocardiographic criteria were used to assess the severity of persistent residual lesions at discharge (Grade 1, no residua; Grade 2, minor residua; and Grade 3, major residua). Outcomes included postdischarge (late) mortality or transplant and unplanned reintervention. Associations between predischarge residual lesion severity and outcomes were assessed by using Cox or competing risk models, adjusting for baseline patient characteristics, case complexity, and preoperative risk factors.

RESULTS

Among the 408 patients who met entry criteria, there were 58 (14.2%) postdischarge deaths or transplants and 208 (51.0%) late reinterventions at a median follow-up of 3.0 years (IQR: 1.1-6.8 years). Greater predischarge residual lesion severity was associated with worse transplant-free survival and freedom from reintervention (both, P < 0.05). On multivariable analyses, Grade 3 patients had an increased risk of postdischarge mortality or transplant (HR: 4.8; 95% CI: 2.0-11; P < 0.001) and late reintervention (subdistribution HR: 2.1; 95% CI: 1.4-3.1; P < 0.001) vs Grade 1 patients.

CONCLUSIONS

Among transplant-free survivors requiring predischarge reinterventions after congenital cardiac surgery, those with persistent major residua have significantly worse long-term outcomes. These high-risk patients warrant closer surveillance.

In vivo evaluation of bioprinted cardiac patches composed of cardiac-specific extracellular matrix and progenitor cells in a model of pediatric heart failure

Pediatric patients with congenital heart defects (CHD) often present with heart failure from increased load on the right ventricle (RV) due to both surgical methods to treat CHD and the disease itself. Patients with RV failure often require transplantation, which is limited due to lack of donor availability and rejection. Previous studies investigating the development and in vitro assessment of a bioprinted cardiac patch composed of cardiac extracellular matrix (cECM) and human c-kit + progenitor cells (hCPCs) showed that the construct has promise in treating cardiac dysfunction. The current study investigates in vivo cardiac outcomes of patch implantation in a rat model of RV failure. Patch parameters including cECM-inclusion and hCPC-inclusion are investigated. Assessments include hCPC retention, RV function, and tissue remodeling (vascularization, hypertrophy, and fibrosis). Animal model evaluation shows that both cell-free and neonatal hCPC-laden cECM-gelatin methacrylate (GelMA) patches improve RV function and tissue remodeling compared to other patch groups and controls. Inclusion of cECM is the most influential parameter driving therapeutic improvements, with or without cell inclusion. This study paves the way for clinical translation in treating pediatric heart failure using bioprinted GelMA-cECM and hCPC-GelMA-cECM patches.

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.

Toward Eliminating Perinatal Comfort Care for Prenatally Diagnosed Severe Congenital Heart Defects: A Vision

Over the past 40 years, the medical and surgical management of congenital heart disease has advanced considerably. However, substantial room for improvement remains for certain lesions that have high rates of morbidity and mortality. Although most congenital cardiac conditions are well tolerated during fetal development, certain abnormalities progress in severity over the course of gestation and impair the development of other organs, such as the lungs or airways. It follows that intervention during gestation could potentially slow or reverse elements of disease progression and improve prognosis for certain congenital heart defects. In this review, we detail specific congenital cardiac lesions that may benefit from fetal intervention, some of which already have documented improved outcomes with fetal interventions, and the state-of-the-science in each of these areas. This review includes the most relevant studies from a PubMed database search from 1970 to the present using key words such as fetal cardiac, fetal intervention, fetal surgery, and EXIT procedure. Fetal intervention in congenital cardiac surgery is an exciting frontier that promises further improvement in congenital heart disease outcomes. When fetuses who can benefit from fetal intervention are identified and appropriately referred to centers of excellence in this area, patient care will improve.

Prevalence of Complications Following Unifocalization and Pulmonary Artery Reconstruction Procedures

Background:

Unifocalization and pulmonary artery reconstructions have been developed to treat complex disorders of pulmonary artery development. These procedures require extremely long periods of cardiopulmonary bypass (CPB) to facilitate surgical repair. The objective of this study was to document the prevalence of complications in patients undergoing unifocalization or pulmonary artery reconstructions associated with prolonged periods of CPB.

Methods:

This was a retrospective review of 100 consecutive patients who underwent unifocalization (n = 66) or pulmonary artery reconstructions (n = 34) with CPB times in excess of five hours. Thirty-eight of these operations were primary procedures, whereas 62 were reoperations.

Results:

The median age at surgery was 15 months, median duration of CPB was 473 minutes, median number of postoperative complications was 5, and the median length of hospital stay was 24 days. The most frequently encountered complications were low cardiac output (43%), open sternum (40%), reintubation (24%), arrhythmia (17%), and bronchoscopy (17%). There was a correlation between the total number of complications and overall length of hospital stay ( R 2 = 0.64). Major adverse cardiac events (MACE) occurred in 11 patients with one hospital mortality. Patients who experienced MACE had a median length of stay that was 35 days longer (56 vs 21 days) than patients who did not experience MACE.

Conclusions:

The data demonstrate that complications were relatively frequent in this cohort of patients and had a linear association with hospital length of stay. Major adverse cardiac events were encountered at a modest prevalence but had a profound impact on measures of outcome.

Bilateral Remote Ischaemic Conditioning in Children (BRICC) trial: protocol for a two-centre, double-blind, randomised controlled trial in young children undergoing cardiac surgery

INTRODUCTION

Myocardial protection against ischaemic-reperfusion injury is a key determinant of heart function and outcome following cardiac surgery in children. However, with current strategies, myocardial injury occurs routinely following aortic cross-clamping, as demonstrated by the ubiquitous rise in circulating troponin. Remote ischaemic preconditioning, the application of brief, non-lethal cycles of ischaemia and reperfusion to a distant organ or tissue, is a simple, low-risk and readily available technique which may improve myocardial protection. The Bilateral Remote Ischaemic Conditioning in Children (BRICC) trial will assess whether remote ischaemic preconditioning, applied to both lower limbs immediately prior to surgery, reduces myocardial injury in cyanotic and acyanotic young children.

METHODS AND ANALYSIS

The BRICC trial is a two-centre, double-blind, randomised controlled trial recruiting up to 120 young children (age 3 months to 3 years) undergoing primary repair of tetralogy of Fallot or surgical closure of an isolated ventricular septal defect. Participants will be randomised in a 1:1 ratio to either bilateral remote ischaemic preconditioning (3×5 min cycles) or sham immediately prior to surgery, with follow-up until discharge from hospital or 30 days, whichever is sooner. The primary outcome is reduction in area under the time-concentration curve for high-sensitivity (hs) troponin-T release in the first 24 hours after aortic cross-clamp release. Secondary outcome measures include peak hs-troponin-T, vasoactive inotrope score, arterial lactate and central venous oxygen saturations in the first 12 hours, and lengths of stay in the paediatric intensive care unit and the hospital.

ETHICS AND DISSEMINATION

The trial was approved by the West Midlands-Solihull National Health Service Research Ethics Committee (16/WM/0309) on 5 August 2016. Findings will be disseminated to the academic community through peer-reviewed publications and presentation at national and international meetings. Parents will be informed of the results through a newsletter in conjunction with a local charity.

TRIAL REGISTRATION NUMBER

ISRCTN12923441.

Pathologic Characteristics of 119 Archived Specimens Showing the Phenotypic Features of Hypoplastic Left Heart Syndrome

To assess the phenotypic variations found among hearts diagnosed at autopsy with hypoplastic left heart syndrome, with attention to implications related to this syndrome as an acquired disease of fetal life, rather than being the consequence of abnormal embryogenesis. We assessed 119 specimens, from 2 archives, diagnosed initially as representing hypoplastic left heart syndrome. Among the 119 specimens, the majority of which had been entered into the archives prior to the availability of surgical treatment for the syndrome, 36 (30%) had the combination of mitral and aortic atresia, 26 (22%) had mitral and aortic stenosis, and 57 (48%) had mitral stenosis combined with aortic atresia. Of the hearts with combined atresia, 92% (33 specimens) had slit-like left ventricles, compared to 12% (3 specimens) of hearts with stenosis of both aortic and mitral valves, and 2 hearts (4%) with mitral stenosis and aortic atresia (P < 0.001). Hypoplasia of the left atrial appendage was present in half (18 specimens, 51%) of those with combined atresia, as opposed to just 18% (10 specimens) of mitral stenosis combined with aortic atresia (P = 0.001). Small left ventricles with valves deemed proportional in size were found in 11 (42%) of those with combined mitral and aortic stenosis. Fibroelastosis was significantly more common in the hearts with mitral stenosis compared to those with mitral atresia (76% vs 11%, P < 0.001). The ascending aorta was significantly smaller in the hearts with aortic atresia. The variability in the morphologic findings support the notion that the lesions seen represent acquired disease occurring subsequent to closure of the embryonic interventricular communication, rather than representing abnormal embryogenesis.

Acute coronary artery obstruction following surgical repair of congenital heart disease

OBJECTIVES

Acute coronary artery obstruction is a rare complication of congenital heart disease surgery but imposes a high burden of morbidity and mortality. Previous case series have described episodes in specific congenital heart lesions or surgical repairs but have not examined the complication in all-comers to congenital heart surgery. We hypothesize that shorter time from a clinically recognized postoperative sentinel event suggestive of coronary ischemia to diagnosis of coronary obstruction is associated with improved clinical outcomes.

METHODS

This was a single-center, retrospective review of patients diagnosed with acute coronary artery obstruction by angiography following surgical repair of congenital heart disease between January 2000 and June 2016.

RESULTS

In total, 34 patients were identified. The most common procedures associated with coronary artery obstruction were the Norwood procedure, arterial switch operation, and aortic valve repair/replacement. In total, 79% required mechanical circulatory support, 41% died, and 27% were listed for heart transplant. Patients who died or were listed for heart transplant had longer median sentinel-event-to-cardiac-catheterization time (28 [6-168] hours vs 10 [3-56] hours, P = .001), and longer median sentinel-event-to-intervention time (32 [11-350] hours vs 13 [5-59] hours, P = .003). Patients with hypoplastic left heart syndrome were at greater risk of death or transplant listing (odds ratio, 9.23, P = .03).

CONCLUSIONS

Time from clinically relevant postoperative sentinel event to diagnosis of coronary artery obstruction by angiography was associated with transplant-listing-free survival. Clinicians should maintain a high index of suspicion for coronary obstruction and consider early catheterization and coronary angiography for patients in whom post-operative coronary compromise is suspected.

The Inadequate Oxygen Delivery Index and Low Cardiac Output Syndrome Score As Predictors of Adverse Events Associated With Low Cardiac Output Syndrome Early After Cardiac Bypass

OBJECTIVES

To evaluate the effectiveness of two scoring systems, the inadequate oxygen delivery index, a risk analytics algorithm (Etiometry, Boston, MA) and the Low Cardiac Output Syndrome Score, in predicting adverse events recognized as indicative of low cardiac output syndrome within 72 hours of surgery.

DESIGN

A retrospective observational pair-matched study.

SETTING

Tertiary pediatric cardiac ICU.

PATIENTS

Children undergoing cardiac bypass for congenital heart defects. Cases experienced an adverse event linked to low cardiac output syndrome in the 72 hours following surgery (extracorporeal membrane oxygenation, renal replacement therapy, cardiopulmonary resuscitation, and necrotizing enterocolitis) and were matched with a control patient on criteria of procedure, diagnosis, and age who experienced no such event.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of a total 536 bypass operations in the study period, 38 patients experienced one of the defined events. Twenty-eight cases were included in the study after removing patients who suffered an event after 72 hours or who had insufficient data. Clinical and laboratory data were collected to derive scores for the first 12 hours after surgery. The inadequate oxygen delivery index was calculated by Etiometry using vital signs and laboratory data. A modified Low Cardiac Output Syndrome Score was calculated from clinical and therapeutic markers. The mean inadequate oxygen delivery and modified Low Cardiac Output Syndrome Score were compared within each matched pair using the Wilcoxon signed-rank test. Inadequate oxygen delivery correctly differentiated adverse events in 13 of 28 matched pairs, with no evidence of inadequate oxygen delivery being higher in cases (p = 0.71). Modified Low Cardiac Output Syndrome Score correctly differentiated adverse events in 23 of 28 matched pairs, with strong evidence of a raised score in low cardiac output syndrome cases (p < 0.01).

CONCLUSIONS

Although inadequate oxygen delivery is an Food and Drug Administration approved indicator of risk for low mixed venous oxygen saturation, early postoperative average values were not linked with medium-term adverse events. The indicators included in the modified Low Cardiac Output Syndrome Score had a much stronger association with the specified adverse events.

The outcome of structural heart defects diagnosed in the first trimester of pregnancy

PURPOSE

We present the results of a detailed protocol of fetal heart examination in the first trimester, in a fetal medicine unit in Romania.

METHODS

Since October 2009, in Filantropia Hospital in Bucharest, we have systematically assessed pregnancies at 11-14 weeks to screen for aneuploidies and for major fetal structural defects. The fetal anatomy examination protocol included the detailed assessment of the fetal heart. This was performed using the same principles as for the second trimester examination, in the entire cohort.

RESULTS

Our population consisted of 7693 patients and 7816 embryos. The protocol for the ultrasound evaluation of the fetal heart was completed for 7597 embryos (97.2%). The outcome is known for 6912 cases (90.9%). We diagnosed 39 heart defects - 30 in the first trimester, seven in the second trimester, two postnatally. Twenty of the 39 heart defects were isolated cardiac malformations. Twelve of the isolated heart defects were diagnosed in the first trimester. The sensitivity of the first trimester ultrasound in identifying major heart defects was 76.92%. The overall survival in cases of isolated congenital heart disease diagnosed in the first trimester was significantly lower than the survival in the cases diagnosed in the second trimester.

CONCLUSIONS

Many (76.92%) of the significant heart defects can be diagnosed by ultrasound examination, in the first trimester. Our study is an argument for developing the multidisciplinary approach needed for the management of early detected structural heart disease.

Validation of acute kidney injury according to the modified KDIGO criteria in infants after cardiac surgery for congenital heart disease

AIM

We aimed to validate the incidence of, risk factors for, and postoperative outcomes of acute kidney injury (AKI) according to the modified Kidney Disease Improving Global Outcomes (m-KDIGO) criteria and compare this criteria with both the paediatric Risk, Injury, Failure, Loss, End-stage disease (pRIFLE) and Acute Kidney Injury Network (AKIN) criteria in infants after cardiac surgery.

METHODS

We retrospectively enrolled 145 consecutive infants who underwent open-heart surgery at Kagoshima University Hospital.

RESULTS

Acute kidney injury was present in 55 (37.9%), 111 (75.9%), and 95 (65.5%) patients according to the m-KDIGO, pRIFLE, and AKIN criteria, respectively. Among these, 71.9% of patients pRIFLE Risk patients and 60.5% of AKIN 1 patients were categorized in the 'no-AKI' group according to the m-KDIGO criteria. Low body weight (m-KDIGO odds ratio [OR], 0.73; P = 0.015; pRIFLE OR, 0.66; P = 0.001; AKIN OR 0.69, P = 0.002) and prolonged cross-clamp time (m-KDIGO OR, 1.02; <P = 0.001; pRIFLE OR, 1.02; P = 0.003; AKIN OR, 1.02; P = 0.001) were independent risk factors for the development of AKI. Further, m-KDIGO-based AKI grade was more strongly associated with higher incidence of requiring renal replacement therapy and mortality than both the pRIFLE- and AKIN- based AKI grade.

CONCLUSION

Application of the three criteria resulted in different AKI incidences, but each criterion could be useful for detecting risk factors for AKI. Notably, using m-KDIGO criteria provides more important subsequent postoperative outcomes. The m-KDIGO AKI criteria describe clinically relevant AKI in infants after cardiac surgery.

Palliative care and paediatric cardiology: current evidence and future directions

Although outcomes for children with heart disease have improved substantially over the past several decades, heart disease remains one of the leading causes of paediatric mortality. For children who progress to advanced heart disease, disease morbidity is high, with many children requiring multiple surgical interventions and long-term intensive care hospitalisations. Care for children with advanced heart disease requires a multidisciplinary approach, and opportunities for earlier integration of palliative care are being explored. This Viewpoint summarises the relevant literature over the past decade. We also identify gaps in parent and provider understanding of prognosis and communication, propose indications for palliative care consultation in paediatric advanced heart disease, and summarise attitudes and perceived barriers to palliative care consultation. Areas for additional research that we identify include paediatric cardiologist education, parental distress, socioeconomic disparities, and patient-reported outcomes. Interdisciplinary clinical and research efforts are required to further advance the field and improve integration of palliative care in the care of children with heart disease.

Catheterization Performed in the Early Postoperative Period After Congenital Heart Surgery in Children

The aim of this study was to describe pediatric patients who underwent early postoperative cardiac catheterization after congenital heart surgery, their clinical indications, findings, interventions, and complications in a cardiovascular center. A descriptive retrospective study was performed. All catheterizations performed within 6 weeks after congenital heart surgery between January 2004 and December 2014 were reviewed. We analyzed 101 early postoperative catheterizations. They were performed on median postoperative day five (IQR: 0-39); the median age was 64 days (IQR: 22-240). The most common diagnoses were single ventricle (53%), left heart obstruction (12%), and tetralogy of fallot or pulmonary atresia with ventricular septal defect (11%). Most common indications were persistent cyanosis (53%), low cardiac output (24%), and residual defect on echocardiogram (20%). Most frequent findings during the catheterization were pulmonary artery stenosis (29%), surgical conduit obstruction (12%), and coarctation or hypoplasia of the aorta (11%). Forty-six (45%) procedures involved intervention. Most frequent interventions were pulmonary artery, aorta, and Blalock-Taussig fistula angioplasty with or without stent implantation. There were adverse effects in 11 cases (11%), and 30-day mortality was 28% (28 patients) with the majority unrelated to the catheterization directly. Although early postoperative catheterizations are high-risk procedures, they are currently a very good option to solve acute problems in critically ill patients. This study provides relevant information for a better understanding and approach to this complex group of patients.

Surgical Treatment for Congenital Heart Defects in Down Syndrome Patients

OBJECTIVE

To analyze data related to surgical treatment in patients with congenital heart defects (CHD) and Down syndrome (DS) based on information from International Quality Improvement Collaborative Database for Congenital Heart Disease (IQIC).

METHODS

Between July 1, 2010 and December 31, 2017, 139 patients with CHD and DS underwent surgery at Hospital de Base and Hospital da Criança e Maternidade de São José do Rio Preto (FUNFARME)/Faculdade de Medicina de São José do Rio Preto - SP (FAMERP). A quantitative, observational and cross-sectional study was performed in which the pre, intra and postoperative data were analyzed in an IQIC database. The data included gender, age, prematurity, weight, preoperative procedures, diagnosis, associated cardiac and non-cardiac anomalies, Risk Adjustment for Congenital Heart Surgery (RACHS-1), type of surgery, cardiopulmonary bypass (CPB), perfusion time, aortic clamping time and CPB temperature, bacterial sepsis, surgical site infection and other infections, length of stay in intensive care unit (ICU), length of hospital stay and in-hospital mortality.

RESULTS

The most prevalent procedures were complete atrioventricular septal defect repair (58 - 39.45%), followed by closure of ventricular septal defect (36 - 24.49%). The RACHS-1 categories 1, 2, 3 and 4 were distributed as 22 (15%); 49 (33.3%); 72 (49%) and 4 (2.7%), respectively. There were no procedures classified as categories 5 or 6. Bacterial sepsis occurred in 10.2% of cases, surgical site infection in 6.1%, other infections in 14.3%. The median length of ICU stay was 5 days and the median length of hospital stay was 11 days. In-hospital mortality was 6.8%.

CONCLUSION

Surgical treatment in patients with CHD and DS usually does not require highly complex surgical procedures, but are affected by infectious complications, resulting in a longer ICU and hospital length of stay with considerable mortality.

Cardiopulmonary Resuscitation in Infants and Children With Cardiac Disease: A Scientific Statement From the American Heart Association

Cardiac arrest occurs at a higher rate in children with heart disease than in healthy children. Pediatric basic life support and advanced life support guidelines focus on delivering high-quality resuscitation in children with normal hearts. The complexity and variability in pediatric heart disease pose unique challenges during resuscitation. A writing group appointed by the American Heart Association reviewed the literature addressing resuscitation in children with heart disease. MEDLINE and Google Scholar databases were searched from 1966 to 2015, cross-referencing pediatric heart disease with pertinent resuscitation search terms. The American College of Cardiology/American Heart Association classification of recommendations and levels of evidence for practice guidelines were used. The recommendations in this statement concur with the critical components of the 2015 American Heart Association pediatric basic life support and pediatric advanced life support guidelines and are meant to serve as a resuscitation supplement. This statement is meant for caregivers of children with heart disease in the prehospital and in-hospital settings. Understanding the anatomy and physiology of the high-risk pediatric cardiac population will promote early recognition and treatment of decompensation to prevent cardiac arrest, increase survival from cardiac arrest by providing high-quality resuscitations, and improve outcomes with postresuscitation care.

Associations Between Unplanned Cardiac Reinterventions and Outcomes After Pediatric Cardiac Operations

BACKGROUND

After pediatric heart operations, we sought to determine the incidence of unplanned cardiac reinterventions during the same hospitalization, assess risk factors for these reinterventions, and explore associations between reinterventions and outcomes. We hypothesized that younger patients undergoing more complex operations would be at greater risk for unplanned cardiac reinterventions and that operative mortality and postoperative length of stay (PLOS) would be greater in patients who undergo reintervention than in those who do not.

METHODS

Patients aged 18 years or younger in The Society of Thoracic Surgeons Congenital Heart Surgery Database (January 2010 to June 2015) were included. We used multivariable regression to evaluate risk factors for unplanned cardiac reintervention (operation or therapeutic catheterization) and associations of reintervention with operative mortality and PLOS.

RESULTS

Of 84,404 patients (117 centers), 21% were neonates and 36% infants. An unplanned cardiac reintervention was performed in 5.4% of patients, including 11.8% of neonates, 5.2% of infants, and 2.8% of children. Independent risk factors for unplanned reintervention included presence of noncardiac anomalies/genetic syndromes, nonwhite race, younger age, lower weight among neonates and infants, prior cardiothoracic operations, preoperative mechanical ventilation, other Society of Thoracic Surgeons preoperative risk factors, and higher Society of Thoracic Surgeons-European Association for Cardiothoracic Surgery Mortality Category (adjusted p < 0.001 for all). Unplanned reintervention was a risk factor for operative mortality (adjusted odds ratio, 5.3; 95% confidence interval, 4.8 to 5.8; p < 0.001) and longer PLOS (adjusted relative risk, 2.3; 95% confidence interval, 2.2 to 2.4; p < 0.001).

CONCLUSIONS

Unplanned cardiac reinterventions are not rare, particularly in neonates, and are independently associated with operative mortality and increased PLOS. Patients at greater risk may be identified preoperatively, presenting opportunities for quality improvement.

Role of terminal warm blood cardioplegia in complex congenital heart surgery

Introduction Myocardial protection is vital to ensure successful open heart surgery. Cardioplegic solution is one method to achieve good myocardial protection. Inevitably, ischemia-reperfusion injury occurs with aortic crossclamping. Histidine-tryptophan-ketoglutarate solution is a frequently used cardioplegia for complex congenital heart surgery. We postulated that addition of terminal warm blood cardioplegia before removal of the aortic crossclamp might improve myocardial protection. Method A randomized controlled trial was conducted on 109 cyanotic patients aged, 1 to 5 years who underwent complex biventricular repair. They were divided into a control group of 55 patients who had histidine-tryptophan-ketoglutarate only and a treatment group of 54 who had histidine-tryptophan-ketoglutarate with terminal warm blood cardioplegia. Endpoints were clinical parameters, troponin I levels, and caspase-3 as an apoptosis marker. Results The incidence of low cardiac output syndrome was 34%, with no significant difference between groups (35.2% vs. 33.3%, p = 0.84). The incidence of arrhythmias in our treatment group was lower compared to the control group (36% vs. 12%, p = 0.005). Troponin I and caspase-3 results did not show any significant differences between groups. For cases with Aristotle score ≥ 10, weak expression of caspase-3 in the treatment group post-cardiopulmonary bypass was lower compared to the control group. Conclusion For complex congenital cardiac surgery, the addition of terminal warm blood cardioplegia does not significantly improve postoperative clinical or metabolic markers.

Prophylactic levosimendan for the prevention of low cardiac output syndrome and mortality in paediatric patients undergoing surgery for congenital heart disease

BACKGROUND

Low cardiac output syndrome remains a serious complication, and accounts for substantial morbidity and mortality in the postoperative course of paediatric patients undergoing surgery for congenital heart disease. Standard prophylactic and therapeutic strategies for low cardiac output syndrome are based mainly on catecholamines, which are effective drugs, but have considerable side effects. Levosimendan, a calcium sensitiser, enhances the myocardial function by generating more energy-efficient myocardial contractility than achieved via adrenergic stimulation with catecholamines. Thus potentially, levosimendan is a beneficial alternative to standard medication for the prevention of low cardiac output syndrome in paediatric patients after open heart surgery.

OBJECTIVES

To review the efficacy and safety of the postoperative prophylactic use of levosimendan for the prevention of low cardiac output syndrome and mortality in paediatric patients undergoing surgery for congenital heart disease.

SEARCH METHODS

We identified trials via systematic searches of CENTRAL, MEDLINE, Embase, and Web of Science, as well as clinical trial registries, in June 2016. Reference lists from primary studies and review articles were checked for additional references.

SELECTION CRITERIA

We only included randomised controlled trials (RCT) in our analysis that compared prophylactic levosimendan with standard medication or placebo, in infants and children up to 18 years of age, who were undergoing surgery for congenital heart disease.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed risk of bias according to a pre-defined protocol. We obtained additional information from all but one of the study authors of the included studies. We used the five GRADE considerations (study limitations, consistency of effect, imprecision, indirectness, and publication bias) to assess the quality of evidence from the studies that contributed data to the meta-analyses for the prespecified outcomes. We created a 'Summary of findings' table to summarise the results and the quality of evidence for each outcome.

MAIN RESULTS

We included five randomised controlled trials with a total of 212 participants in the analyses. All included participants were under five years of age. Using GRADE, we assessed there was low-quality evidence for all analysed outcomes. We assessed high risk of performance and detection bias for two studies due to their unblinded setting. Levosimendan showed no clear effect on risk of mortality (risk ratio (RR) 0.47, 95% confidence interval (CI) 0.12 to 1.82; participants = 123; studies = 3) and no clear effect on low cardiac output syndrome (RR 0.64, 95% CI 0.39 to 1.04; participants = 83; studies = 2) compared to standard treatments. Data on time-to-death were not available from any of the included studies.There was no conclusive evidence on the effect of levosimendan on the secondary outcomes. The length of intensive care unit stays (mean difference (MD) 0.33 days, 95% CI -1.16 to 1.82; participants = 188; studies = 4), length of hospital stays (MD 0.26 days, 95% CI -3.50 to 4.03; participants = 75; studies = 2), duration of mechanical ventilation (MD -0.04 days, 95% CI -0.08 to 0.00; participants = 208; studies = 5), and the risk of mechanical circulatory support or cardiac transplantation (RR 1.49, 95% CI 0.19 to 11.37; participants = 60; studies = 2) did not clearly differ between the groups. Published data about adverse effects of levosimendan were limited. A meta-analysis of hypotension, one of the most feared side effects of levosimendan, was not feasible because of the heterogeneous expression of blood pressure values.

AUTHORS' CONCLUSIONS

The current level of evidence is insufficient to judge whether prophylactic levosimendan prevents low cardiac output syndrome and mortality in paediatric patients undergoing surgery for congenital heart disease. So far, no significant differences have been detected between levosimendan and standard inotrope treatments in this setting.The authors evaluated the quality of evidence as low, using the GRADE approach. Reasons for downgrading were serious risk of bias (performance and detection bias due to unblinded setting of two RCTs), serious risk of inconsistency, and serious to very serious risk of imprecision (small number of included patients, low event rates).

Prophylactic levosimendan for the prevention of low cardiac output syndrome and mortality in paediatric patients undergoing surgery for congenital heart disease

BACKGROUND

Low cardiac output syndrome remains a serious complication, and accounts for substantial morbidity and mortality in the postoperative course of paediatric patients undergoing surgery for congenital heart disease. Standard prophylactic and therapeutic strategies for low cardiac output syndrome are based mainly on catecholamines, which are effective drugs, but have considerable side effects. Levosimendan, a calcium sensitiser, enhances the myocardial function by generating more energy-efficient myocardial contractility than achieved via adrenergic stimulation with catecholamines. Thus potentially, levosimendan is a beneficial alternative to standard medication for the prevention of low cardiac output syndrome in paediatric patients after open heart surgery.

OBJECTIVES

To review the efficacy and safety of the postoperative prophylactic use of levosimendan for the prevention of low cardiac output syndrome and mortality in paediatric patients undergoing surgery for congenital heart disease.

SEARCH METHODS

We identified trials via systematic searches of CENTRAL, MEDLINE, Embase, and Web of Science, as well as clinical trial registries, in June 2016. Reference lists from primary studies and review articles were checked for additional references.

SELECTION CRITERIA

We only included randomised controlled trials (RCT) in our analysis that compared prophylactic levosimendan with standard medication or placebo, in infants and children up to 18 years of age, who were undergoing surgery for congenital heart disease.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed risk of bias according to a pre-defined protocol. We obtained additional information from all but one of the study authors of the included studies. We used the five GRADE considerations (study limitations, consistency of effect, imprecision, indirectness, and publication bias) to assess the quality of evidence from the studies that contributed data to the meta-analyses for the prespecified outcomes. We created a 'Summary of findings' table to summarise the results and the quality of evidence for each outcome.

MAIN RESULTS

We included five randomised controlled trials with a total of 212 participants in the analyses. All included participants were under five years of age. Using GRADE, we assessed there was low-quality evidence for all analysed outcomes. We assessed high risk of performance and detection bias for two studies due to their unblinded setting. Levosimendan showed no clear effect on risk of mortality (risk ratio (RR) 0.47, 95% confidence interval (CI) 0.12 to 1.82; participants = 123; studies = 3) and no clear effect on low cardiac output syndrome (RR 0.64, 95% CI 0.39 to 1.04; participants = 83; studies = 2) compared to standard treatments. Data on time-to-death were not available from any of the included studies.There was no conclusive evidence on the effect of levosimendan on the secondary outcomes. The levosimendan groups had shorter length of intensive care unit stays (mean difference (MD) 0.33 days, 95% CI -1.16 to 1.82; participants = 188; studies = 4; I² = 35%), length of hospital stays (0.26 days, 95% CI -3.50 to 4.03; participants = 75; studies = 2), and duration of mechanical ventilation (MD -0.04 days, 95% CI -0.08 to 0.00; participants = 208; studies = 5; I² = 0%). The risk of mechanical circulatory support or cardiac transplantation favoured the levosimendan groups (RR 1.49, 95% CI 0.19 to 11.37; participants = 60; studies = 2). Published data about adverse effects of levosimendan were limited. A meta-analysis of hypotension, one of the most feared side effects of levosimendan, was not feasible because of the heterogeneous expression of blood pressure values.

AUTHORS' CONCLUSIONS

The current level of evidence is insufficient to judge whether prophylactic levosimendan prevents low cardiac output syndrome and mortality in paediatric patients undergoing surgery for congenital heart disease. So far, no significant differences have been detected between levosimendan and standard inotrope treatments in this setting.The authors evaluated the quality of evidence as low, using the GRADE approach. Reasons for downgrading were serious risk of bias (performance and detection bias due to unblinded setting of two RCTs), serious risk of inconsistency, and serious to very serious risk of imprecision (small number of included patients, low event rates).

Discrepancies Between Clinical Diagnoses and Autopsy Findings in Critically Ill Children: A Prospective Study

OBJECTIVES

To evaluate the discrepancies between clinical and autopsy diagnoses in patients who died in the pediatric intensive care units (PICUs) of a tertiary care university hospital.

METHODS

A prospective study of all consecutive autopsies discussed at monthly mortality conferences over 5 years. Discrepancies between premortem and autopsy diagnoses were classified according to modified Goldman et al criteria.

RESULTS

From January 1, 2011, to December 31, 2015, a total of 2,679 children were admitted to the two PICUs of our hospital; 257 (9.6%) died, 150 (58.4%) underwent autopsy, and 123 were included. Complete concordance between clinical and postmortem diagnoses was observed in 86 (69.9%) patients; 20 (16.3%) had a class I discrepancy, and eight (6.5%) had a class II discrepancy. Comparing 2011 and 2015, the rate of major discrepancies decreased from 31.6% to 15%.

CONCLUSIONS

Our results emphasize the importance of autopsy to clarify the cause of death and its potential contribution to improvement of team performance and quality of care.

Usefulness of the maximum rate of pressure rise in the central and peripheral arteries after weaning from cardiopulmonary bypass in pediatric congenital heart surgery: A retrospective analysis

The maximum rate of pressure rise (dP/dtmax) in radial artery has been proposed as a noninvasive surrogate of aortic dp/dtmax, reflecting left ventricular (LV) contractility in children. The aim of this study was to investigate relationship between aortic and radial dp/dtmax at weaning from cardiopulmonary bypass (CPB) and usefulness of these indices for estimating postoperative outcomes in pediatric congenital heart surgery.Aortic and radial arterial pressure waveforms were analyzed simultaneously during weaning from CPB in 29 congenital heart surgery. The maximum first derivatives of aortic and radial arterial waveforms were calculated and averaged from 3 consecutive respiratory cycles. We obtained the maximum vasoactive inotropic score during the first 36 postoperative hours, LV ejection fraction, and fractional shortening on transthoracic echocardiography performed within postoperative day 7.A significant difference between aortic and radial dP/dtmax was observed (mean difference 356 mm Hg/s, 44% of averages), and radial dP/dtmax was weakly correlated with aortic dP/dtmax (r =0.373, P = 0.047). Aortic dP/dtmax was significantly associated with the maximum vasoactive inotropic score (P < 0.001), postoperative LV ejection fraction (P = 0.018), and fractional shortening (P = 0.015); however, radial dP/dtmax was not. On Receiver operating characteristic analysis, aortic dP/dtmax had a greater area under the curve than radial dP/dtmax in predicting higher vasoactive inotropic score (0.827 vs 0.673).Immediately after CPB in pediatric congenital heart surgery, radial dP/dtmax may not replace aortic dP/dtmax because of a discrepancy between central and peripheral arterial waveforms. In this critical period, aortic dP/dtmax can be useful to estimate postoperative ventricular function rather than peripherally derived dP/dtmax.

Seminal Postoperative Complications and Mode of Death After Pediatric Cardiac Surgical Procedures

BACKGROUND

Understanding the seminal complications leading to death after pediatric cardiac surgical procedures may provide opportunities to reduce mortality. This study analyzed all deaths at two pediatric cardiac surgical programs and developed a method to identify the seminal complications and modes of death.

METHODS

Trained nurses abstracted all cases of in-hospital mortality meeting inclusion criteria from each site over 5 years (2008 to 2012). Complication definitions were consistent with those of a multicenter clinical registry. An adjudication committee assigned a seminal complication in each case (the complication initiating the cascade of events leading to death). Seminal complications were grouped into categories to designate "mode of death." The epidemiology of seminal complications and of mode of death was described.

RESULTS

In 191 subjects, low cardiac output syndrome (71% of all subjects), cardiac arrest (52%), and arrhythmia (48%) were the most common complications. The committee assigned low cardiac output syndrome (30%), failure to separate from bypass (16%), and cardiac arrest (12%) most frequently as seminal complications. Seminal complications occurred a median 2 hours (interquartile range [IQR], 0 to 35 hours) postoperatively. Patients experienced a median of seven (IQR, 3 to 12) additional complications before death at a median of 15 days (IQR, 4 to 46). Systemic circulatory failure was the most common mode of death (51%), followed by inadequate pulmonary blood flow (13%) and cardiac arrest (12%).

CONCLUSIONS

Seminal complications occurred early postoperatively, and systemic circulatory failure was the most common mode of death. Our classification system is likely scalable for subsequent multicenter analysis to understand cause-specific mortality variation across hospitals and to drive quality improvement.

Procalcitonin as a biomarker of bacterial infection in pediatric patients after congenital heart surgery

Background:

Bacterial infection (BI) after congenital heart surgery (CHS) is associated with increased morbidity and is difficult to differentiate from systemic inflammatory response syndrome caused by cardiopulmonary bypass (CPB). Procalcitonin (PCT) has emerged as a reliable biomarker of BI in various populations.

Aim:

To determine the optimal PCT threshold to identify BI among children suspected of having infection following CPB.

Setting and Design:

Single-center retrospective observational study.

Materials and Methods:

Medical records of all the patients admitted between January 2013 and April 2015 were reviewed. Patients in the age range of 0-21 years of age who underwent CHS requiring CPB in whom PCT was drawn between postoperative days 0-8 due to suspicion of infection were included.

Statistical Analysis:

The Wilcoxon rank-sum test was used for nonparametric variables. The diagnostic performance of PCT was evaluated using a receiver operating characteristic (ROC) curve.

Results:

Ninety-eight patients were included. The median age was 2 months (25th and 75th interquartile of 0.1-7.5 months). Eleven patients were included in the BI group. The median PCT for the BI group (3.42 ng/mL, 25th and 75th interquartile of 2.34-5.67) was significantly higher than the median PCT for the noninfected group (0.8 ng/mL, 25th and 75th interquartile 0.38-3.39), P = 0.028. The PCT level that yielded the best compromise between the sensitivity (81.8%) and specificity (66.7%) was 2 ng/mL with an area under the ROC curve of 0.742.

Conclusion:

A PCT less than 2 ng/mL makes BI unlikely in children suspected of infection after CHS.

Modes of Death in a Pediatric Cardiac ICU

OBJECTIVE

To determine epidemiology and proximate causes of death in a pediatric cardiac ICU in Southern Europe.

DESIGN

Retrospective chart review.

SETTING

Single-center institution.

PATIENTS

We concurrently identified 57 consecutive patients who died prior to discharge from the cardiac ICU.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Over the study period, there were 57 deaths for a combined mortality rate of 2.4%. Four patients (7%) were declared brain dead, 25 patients (43.8%) died after a failed resuscitation attempt, and 28 patients (49.1%) died after withholding or withdrawal of life-sustaining treatment. Cardiorespiratory failure was the most frequent proximate cause of death (39, 68.4%) followed by brain injury (14, 24.6%) and septic shock (4, 7%). Older age at admission, presence of mechanical ventilation and/or device-dependent nutrition support, patients on a left-ventricular assist device and longer cardiac ICU stay were more likely to have life support withheld or withdrawn.

CONCLUSIONS

Almost half of the deaths in the cardiac ICU are predictable, and they are anticipated by the decision to limit life-sustaining treatments. Brain injuries play a direct role in the death of 25% of patients who die in the cardiac ICU. Patients with left-ventricular assist device are associated with withdrawal of treatment.

Myocardial Oxidative Stress in Infants Undergoing Cardiac Surgery

Cardiac surgery for congenital heart disease often necessitates a period of myocardial ischemia during cardiopulmonary bypass and cardioplegic arrest, followed by reperfusion after aortic cross-clamp removal. In experimental models, myocardial ischemia-reperfusion is associated with significant oxidative stress and ventricular dysfunction. A prospective observational study was conducted in infants (<1 year) who underwent elective surgical repair of a ventricular septal defect (VSD) or tetralogy of Fallot (TOF). Blood samples were drawn following anesthetic induction (baseline) and directly from the coronary sinus at 1, 3, 5, and 10 min following aortic cross-clamp removal. Samples were analyzed for oxidant stress using assays for thiobarbituric acid-reactive substances, protein carbonyl, 8-isoprostane, and total antioxidant capacity. For each subject, raw assay data were normalized to individual baseline samples and expressed as fold-change from baseline. Results were compared using a one-sample t test with Bonferroni correction for multiple comparisons. Sixteen patients (ten with TOF and six with VSD) were enrolled in the study, and there were no major postoperative complications observed. For the entire cohort, there was an immediate, rapid increase in myocardial oxidative stress that was sustained for 10 min following aortic cross-clamp removal in all biomarker assays (all P < 0.01), except total antioxidant capacity. Infant cardiac surgery is associated with a rapid, robust, and time-dependent increase in myocardial oxidant stress as measured from the coronary sinus in vivo. Future studies with larger enrollment are necessary to assess any association between myocardial oxidative stress and early postoperative outcomes.

Pediatric Pulmonary Hypertension: Guidelines From the American Heart Association and American Thoracic Society

Pulmonary hypertension is associated with diverse cardiac, pulmonary, and systemic diseases in neonates, infants, and older children and contributes to significant morbidity and mortality. However, current approaches to caring for pediatric patients with pulmonary hypertension have been limited by the lack of consensus guidelines from experts in the field. In a joint effort from the American Heart Association and American Thoracic Society, a panel of experienced clinicians and clinician-scientists was assembled to review the current literature and to make recommendations on the diagnosis, evaluation, and treatment of pediatric pulmonary hypertension. This publication presents the results of extensive literature reviews, discussions, and formal scoring of recommendations for the care of children with pulmonary hypertension.

Collaborative quality improvement in the cardiac intensive care unit: development of the Paediatric Cardiac Critical Care Consortium (PC4)

Despite many advances in recent years for patients with critical paediatric and congenital cardiac disease, significant variation in outcomes remains across hospitals. Collaborative quality improvement has enhanced the quality and value of health care across specialties, partly by determining the reasons for variation and targeting strategies to reduce it. Developing an infrastructure for collaborative quality improvement in paediatric cardiac critical care holds promise for developing benchmarks of quality, to reduce preventable mortality and morbidity, optimise the long-term health of patients with critical congenital cardiovascular disease, and reduce unnecessary resource utilisation in the cardiac intensive care unit environment. The Pediatric Cardiac Critical Care Consortium (PC4) has been modelled after successful collaborative quality improvement initiatives, and is positioned to provide the data platform necessary to realise these objectives. We describe the development of PC4 including the philosophical, organisational, and infrastructural components that will facilitate collaborative quality improvement in paediatric cardiac critical care.

Preoperative factors as a predictor for early postoperative outcomes after repair of congenital transposition of the great arteries

Transposition of the great arteries (TGA) requires early surgical repair during the neonatal period. Several preoperative factors have been identified for the postoperative poor outcome after arterial switch operation (ASO). However, the data remain uncertain an association. Therefore, we investigated the preoperative factors which affect the early postoperative outcomes. Between March 2005 and May 2012, a retrospective study was performed which included 126 infants with an ASO for TGA. Preoperative data included the vasoactive inotropic score (VIS) and baseline hemodynamics. Early postoperative outcomes included the duration of mechanical ventilation, the length of stay in the intensive care unit and hospital, and early mortality. Multivariate linear regression and receiver operating characteristics analysis were performed. The duration of mechanical ventilation was significantly correlated with the preoperative mechanical ventilator support and VIS, and CPB time. On multivariate linear regression analysis, a higher preoperative VIS, preoperative B-type natriuretic peptide (BNP) level, and the CPB time were identified as independent risk factors for delayed mechanical ventilation. Preoperative VIS (OR 1.154, 95 % CI 1.024-1.300) and the CPB time (OR 1.034, 95 % CI 1.009-1.060) were independent parameters predicting early mortality. A preoperative VIS of 12.5 had the best combined sensitivity (83.3 %) and specificity (85.3 %) and an AUC of 0.852 (95 % CI 0.642-1.061) predicted early mortality. Our results suggest that preoperative VIS and BNP can predict the need for prolonged postoperative mechanical ventilation. Moreover, preoperative VIS may be used as a simple and feasible indicator for predicting early mortality.

Unplanned reinterventions are associated with postoperative mortality in neonates with critical congenital heart disease

OBJECTIVE

Neonates with critical congenital heart disease remain at risk of adverse outcomes after cardiac surgery. Residual or undiagnosed anatomic lesions might be contributory. The present study aimed to describe the incidence and type of cardiac lesions that lead to early, unplanned cardiac reintervention, identify the risk factors for unplanned reintervention, and explore the associations between unplanned reinterventions and hospital mortality.

METHODS

The present single-center retrospective cohort study included 943 consecutive neonates with critical congenital heart disease who underwent cardiac surgery from 2002 to 2008. An unplanned cardiac reintervention was defined as a cardiac reoperation or interventional cardiac catheterization performed during the same hospitalization as the initial operation. Multivariate logistic regression analyses were used to identify the risk factors for unplanned cardiac reintervention and hospital mortality.

RESULTS

Of the 943 neonates, 104 (11%) underwent an unplanned cardiac reintervention. The independent predictors of unplanned reintervention included prenatal diagnosis, lower birth weight, need for mechanical ventilation before the initial cardiac operation, lower attending surgeon experience, and greater Risk Adjustment in Congenital Heart Surgery, version 1, category. Those who underwent reintervention had increased hospital mortality (n = 33/104, 32%) relative to those who did not (n = 31/839, 4%; adjusted odds ratio, 8.6; 95% confidence interval, 4.7 to 15.6; P < .001). The mortality rates among patients undergoing surgical reintervention (23/66, 35%) or transcatheter reintervention (4/16, 25%), or both (6/22, 27%) were similar (P = .66).

CONCLUSIONS

The need for unplanned cardiac reintervention in neonates with critical congenital heart disease is strongly associated with increased mortality. Early unplanned reinterventions might be an important covariate in outcomes studies and useful as a quality improvement measure.