Prevalence, Predictors, and Prognostic Value of Renal Dysfunction in Adults With Congenital Heart Disease

Pathogenesis and treatment of the cardiorenal syndrome: Implications of L-arginine-nitric oxide pathway impairment

A highly complex interplay exists between the heart and kidney in the setting of both normal and abnormal physiology. In the context of heart failure, a pathophysiological condition termed the cardiorenal syndrome (CRS) exists whereby dysfunction in the heart or kidney can accelerate pathology in the other organ. The mechanisms that underpin CRS are complex, and include neuro-hormonal activation, oxidative stress and endothelial dysfunction. The endothelium plays a central role in the regulation of both cardiac and renal function, and as such impairments in endothelial function can lead to dysfunction of both these organs. In particular, reduced bioavailability of nitric oxide (NO) is a key pathophysiologic component of endothelial dysfunction. The synthesis of NO by the endothelium is critically dependent on the plasmalemmal transport of its substrate, L-arginine, via the cationic amino acid transporter-1 (CAT1). Impaired L-arginine-NO pathway activity has been demonstrated individually in heart and renal failure. Recent findings suggest abnormalities of the L-arginine-NO pathway also play a role in the pathogenesis of CRS and thus this pathway may represent a potential new target for the treatment of heart and renal failure.

Hypoalbuminaemia predicts outcome in adult patients with congenital heart disease

BACKGROUND

In patients with acquired heart failure, hypoalbuminaemia is associated with increased risk of death. The prevalence of hypoproteinaemia and hypoalbuminaemia and their relation to outcome in adult patients with congenital heart disease (ACHD) remains, however, unknown.

METHODS

Data on patients with ACHD who underwent blood testing in our centre within the last 14 years were collected. The relation between laboratory, clinical or demographic parameters at baseline and mortality was assessed using Cox proportional hazards regression analysis.

RESULTS

A total of 2886 patients with ACHD were included. Mean age was 33.3 years (23.6-44.7) and 50.1% patients were men. Median plasma albumin concentration was 41.0 g/L (38.0-44.0), whereas hypoalbuminaemia (<35 g/L) was present in 13.9% of patients. The prevalence of hypoalbuminaemia was significantly higher in patients with great complexity ACHD (18.2%) compared with patients with moderate (11.3%) or simple ACHD lesions (12.1%, p<0.001). During a median follow-up of 5.7 years (3.3-9.6), 327 (11.3%) patients died. On univariable Cox regression analysis, hypoalbuminaemia was a strong predictor of outcome (HR 3.37, 95% CI 2.67 to 4.25, p<0.0001). On multivariable Cox regression, after adjusting for age, sodium and creatinine concentration, liver dysfunction, functional class and disease complexity, hypoalbuminaemia remained a significant predictor of death.

CONCLUSIONS

Hypoalbuminaemia is common in patients with ACHD and is associated with a threefold increased risk of risk of death. Hypoalbuminaemia, therefore, should be included in risk-stratification algorithms as it may assist management decisions and timing of interventions in the growing ACHD population.

Critical care management of the adult patient with congenital heart disease: focus on postoperative management and outcomes

OPINION STATEMENT

Advances in surgical techniques and in the medical management of children with congenital heart disease has increased survival into adulthood, resulting in a population of adults with congenital heart disease now surpassing the pediatric population in numbers. Furthermore, many of the patients will require repeat surgical, catheter-based, procedures and/or obstetrical care in their adult lives, and understanding the specific cardiopulmonary physiology and the involvement of other organ systems is critical to successful intervention. A team approach, with consultants from medical specialties in the setting of an established adult congenital heart center, is the optimal setting for superior outcomes. In this review, we discuss critical care management of the adult congenital heart disease patient in the perioperative period.

Clinical and prognostic implications of plasma NGAL and NT-proBNP in adult patients with congenital heart disease

BACKGROUND

Prognostic value of NT-proBNP is well established in patients with congenital heart disease. Growing evidence suggests that plasma NGAL is elevated in heart failure but data is limited in congenital heart disease. This study investigates the combined prognostic value of plasma NGAL with plasma NT-proBNP in adult patients with congenital heart disease.

METHODS

Plasma levels of NT-proBNP and NGAL were measured in 76 consecutive adult patients (33 men, mean age 31.7 ± 14 yrs) with congenital heart disease and normal values of serum creatinine. Patients were divided in three groups: A: simple cardiac lesions, B: complex cardiac lesions and C: cyanotic lesions. Patients were also monitored for long-term major cardiovascular events: death, hospitalization, NYHA class worsening, new onset of arrhythmias, surgical or percutaneous intervention.

RESULTS

NGAL value was significantly different between groups: In group A median NGAL value was 64.5 ± 36.7 ng/ml, in group B median NGAL value was 88.77 ± 36.17 ng/ml and in group C median NGAL value was 121 ± 40 ng/ml (group A vs. group B: p = 0.048, group B vs. group C: p = 0.037, group A vs. group C: p = 0.003). Plasma NT-proBNP predicted all events (HR = 1.001, CI = 1.001-1.002, p = 0.0006) as well as cardiovascular death alone (HR = 1.001, CI = 1.001-1.002, p = 0.0004); plasma NGAL was the only predictor of cardiovascular death (HR = 1.017, CI = 1.001-1.033, p = 0.037).

CONCLUSION

Plasma NGAL levels were lower in patients with simple congenital disease compared to patients with complex congenital heart disease and cyanotic congenital heart disease. Plasma NGAL levels correlated with NT-proBNP and could predict cardiovascular death in this small cohort of patients.

Prevalence and predictors of decreased glomerular filtration rate in tibetan children with congenital heart disease

OBJECTIVES

To assess the prevalence of decreased glomerular filtration rate (GFR) in Tibetan children with congenital heart disease (CHD) and its associated risk factors.

METHODS

A total of 207 Tibetan children attending authors' center for treatment of CHD from May 2012 through November 2012, were included in the study. GFR was estimated with the Schwartz formula (eGFR).

RESULTS

The mean eGFR was 104.3±16.6 mL/min/1.73 m2, and decreased in 21 children (10.1%). In the cyanotic category, eGFR was decreased only in severely cyanotic individuals. In the acyanotic category with left ventricular overload, children with decreased eGFR were younger, more commonly lived in areas above 4,700 m, and had higher left ventricular internal dimensions indexed by body surface areas (LVID/BSA) (53.8±6.9 vs. 40.1±6.8 mm/m2, P<0.001) compared with those with normal eGFR. Multivariate analysis identified LVID/BSA as the only independent predictor for decreased eGFR (OR: 1.329, 95% CI: 1.177~1.501, P<0.001). Receiver operating characteristic analysis showed the area under curve for LVID/BSA was 0.921 (95% CI: 0.863 ~ 0.980, P<0.001), with the optimal cutoff value of 49.8 mm/m2 (sensitivity: 75.0%, specificity: 93.9%). In the remaining category, decreased eGFR was only observed in those living above 4,700 m.

CONCLUSIONS

One tenth of Tibetan children with CHD had decreased eGFR. The risk factors included severe cyanosis, younger age, living above 4,700 m and higher LVID/BSA.

The exceptional and far-flung manifestations of heart failure in Eisenmenger syndrome

Dramatic advances in the diagnosis and treatment of congenital heart disease (CHD), the most common inborn defect, has resulted in a growing population of adults with CHD. Eisenmenger syndrome (ES) represents the extreme form of pulmonary arterial hypertension associated with CHD, characterized by markedly increased pulmonary vascular resistance with consequently reversed or bidirectional shunting. While ES is a direct consequence of a heart defect, it is a fundamentally multisystem syndrome with wide-ranging clinical manifestations. The introduction of targeted pulmonary hypertension therapies aimed has subtly shifted clinical focus from preventing iatrogenic and other adverse events toward cautious therapeutic activism.

Myocardial fibrosis in Eisenmenger syndrome: a descriptive cohort study exploring associations of late gadolinium enhancement with clinical status and survival

BACKGROUND

A relationship between myocardial fibrosis and ventricular dysfunction has been demonstrated using late gadolinium enhancement (LGE) in the pressure-loaded right ventricle from congenital heart defects. In patients with Eisenmenger syndrome (ES), the presence of LGE has not been investigated. The aims of this study were to detect any myocardial fibrosis in ES and describe major clinical variables associated with the finding.

METHODS

From 45 subjects screened, 30 subjects (age 43 ± 13 years, 20 female) underwent prospective cardiovascular magnetic resonance with LGE to quantify biventricular volume and function as well as maximal and submaximal exercise during a single visit. Standard cine acquisitions were obtained for ventricular volume and function. Further imaging was performed after administration of 0.1 mmol/kg gadolinium contrast. Regions of LGE were evaluated qualitatively and quantitatively by manual contouring of identified areas, with total area expressed as a percentage of mass. Patients were followed prospectively (mean follow up 7.4 ± 0.4 years) and any deaths recorded. Patients with LGE findings were compared to those without.

RESULTS

LGE was present in 22/30 (73%) patients, specifically in RV myocardium (70%), RV trabeculae (60%), LV myocardium (33%) or LV papillary muscles (30%), though in small amounts (mean 1.4% of total ventricular mass, range 0.16 - 6.0%). Those with any LGE were not different in age, history of arrhythmia, desaturation, nor hemoglobin, nor ventricular size, mass, or function. Exercise capacity was low, but also not different between those with and without LGE. Similarly no significant associations were found with amount of fibrosis. There were five deaths among patients with LGE, versus two in patients without, but no difference in survival (log rank =0.03, P = 0.85).

CONCLUSIONS

Myocardial fibrosis by LGE is common in ES, though not extensive. The presence and quantity of LGE did not correlate with ventricular size, function, degree of cyanosis, exercise capacity, or survival in this pilot study. More data are clearly required before recommendations for routine use of LGE in these patients can be made.

Low fasting plasma glucose level predicts morbidity and mortality in symptomatic adults with congenital heart disease

BACKGROUND

Adults with complex congenital heart disease (ACHD) have a high prevalence of abnormal glucose regulation (AGR: impaired glucose tolerance and diabetes mellitus). However, the impact of AGR on the prognosis remains unclear.

PURPOSE

Our purpose was to clarify the prognostic value of AGR in ACHD.

METHODS AND RESULTS

We performed a 75 g oral glucose tolerance test in 438 consecutive patients with ACHD (age 26 ± 8 years), including 38 unrepaired, 148 Fontan, 252 biventricular, and 27 healthy subjects and investigated associations between AGR and clinical events that required hospitalization or caused deaths from all-causes. When compared with the healthy group, fasting blood glucose level (FPG, mg/dl) was lower in the unrepaired and Fontan subjects (p<0.05-0.01) and the prevalence of low FPG (≤ 80 mg/dl) was also higher in the unrepaired (58%), Fontan (47%), and biventricular group (33%) than in the healthy control (11%) (p<0.0001). Postprandial hyperglycemia (area under the curve of glucose: PG-AUC) was higher in all ACHD groups (p<0.0001 for all). New York Heart Association class and lower FPG independently predicted the hospitalization (FPG ≤ 84 mg/dl) and mortality (FPG ≤ 80 mg/dl) (p<0.05-0.0001), while the PG-AUC was not an independent predictor. When compared with the asymptomatic ACHD, symptomatic ACHD with lower FPG had high hazard ratios of 2.2 (95% confidence interval [CI]: 1.3-3.8, p<0.002) and 3.3 (95% CI: 1.2-11.9, p<0.03) for the hospitalizations and all-cause mortality, respectively.

CONCLUSIONS

Low FPG is not uncommon in ACHD and the low FPG predicts the morbidity and all-cause mortality in symptomatic ACHD.

Perioperative Morbidity and Mortality after Noncardiac Surgery in Young Adults with Congenital or Early Acquired Heart Disease: A Retrospective Cohort Analysis of the National Surgical Quality Improvement Program Database

An increasing number of patients with congenital heart disease survive to adulthood. Expert opinion suggests that noncardiac surgery is a high-risk event, but few data describe perioperative outcomes in this population. Using the National Surgical Quality Improvement Program database, we identified a cohort of patients aged 18 to 39 years with prior heart surgery who underwent noncardiac surgery between 2005 and 2010. A comparison cohort with no prior cardiovascular surgery was matched on age, sex, race/ethnicity, operation year, American Society of Anesthesiologists physical status, and Current Procedural Terminology code. A study cohort consisting of 1191 patients was compared with a cohort of 5127 patients. Baseline dyspnea, inpatient status at the time of surgery, and a prior operation within 30 days were more common in the study cohort. Postoperative outcomes were less favorable in the study cohort. Observed rates of death, peri-operative cardiac arrest, myocardial infarction, stroke, respiratory complications, renal failure, sepsis, venous thromboembolism, perioperative transfusion, and reoperation were significantly higher in the study cohort ( P < 0.01 for all). Mean postoperative length of stay was greater in the study cohort (5.8 vs 3.6 days, P < 0.01). Compared with a matched control cohort, young adult patients with a history of prior cardiac surgery experienced significantly greater perioperative morbidity and mortality after noncardiac surgery. A history of prior cardiac surgery represents a marker of substantial perioperative risk in this young population that is not accounted for by the matched variables. These results suggest that adult patients with congenital heart disease are at risk for adverse outcomes and support the need for further registry-based investigations.

Incidence, risk factors and clinical outcomes for acute kidney injury after aortic arch repair in paediatric patients

OBJECTIVES

Acute kidney injury (AKI) is common after paediatric cardiac surgery and associated with increased morbidity and mortality. Aortic arch surgery may be an independent risk factor for AKI because of circulatory arrest below the descending thoracic artery during anastomosis. We investigated the surgical outcomes associated with AKI after aortic arch repair in paediatric patients.

METHODS

We retrospectively analysed 120 paediatric patients who underwent aortic arch repair between 2003 and 2012. AKI was defined according to the paediatric-modified risk, injury, failure, loss and end-stage kidney disease criteria. The incidence, clinical outcomes and risk factors for AKI were analysed.

RESULTS

Aortic arch repair was performed for coarctation of aorta in 97 patients and interrupted aortic arch in 23 patients. The median age and body weight at the time of surgery were 16.5 days and 3.3 kg, respectively. The mean duration of the follow-up was 3.9 years. AKI developed in 42 patients (36.8%) and peritoneal dialysis (PD) was applied in 20 patients (16.7%). The recovery of renal function began a mean of 3.8 days after conservative management, and full recovery occurred a mean of 6.7 days after conservative management. A lower body weight (<3.0 kg) (odds ratio [OR]: 7.569, P = 0.009) and the absence of prerenal impairment (OR: 9.876, P = 0.041) were shown to be independent risk factors. Patients who required PD had prolonged intensive care unit and hospital stays (P = 0.002 and P = 0.003).

CONCLUSIONS

AKI is common in low-birth-weight patients after aortic arch repair surgery. However, patients recover from AKI after conservative management. Requiring PD increases the morbidity associated with AKI.

Comparison of prognostic variables in children and adults with Fontan circulation

BACKGROUND

Non-cardiac complications, such as hepato-renal and metabolic problems, are emerging late after the Fontan operation due to its unique hemodynamics. Consequently, associations between clinical variables and postoperative outcome may change during the prolonged postoperative course.

METHODS AND RESULTS

To determine if child and adult Fontan patients differ in the impact of cardiac and non-cardiac variables on clinical outcome, we prospectively evaluated associations between hemodynamics, neurohumoral factors, exercise variables, hepato-renal function and metabolic variables and unscheduled hospitalization, including death in 167 consecutive child and 116 adult Fontan patients. When compared with child patients, the adult patients showed higher rates of medications, lower cardiac index, higher values of natriuretic peptides, greater renal dysfunction, more cholestatic livers, and more impaired responses to exercise (p<0.05-0.0001). During the follow-up of 3.7 ± 2.1 years, 64 clinical events (37 in adults), including 13 deaths, occurred. A high CVP and low arterial oxygen satutration strongly predicted the child events (p<0.001), whereas these prognostic parameters were marginal in the adults. Instead, renal dysfunction and metabolic abnormality predicted adult events (p<0.05). Neurohumoral activation, low albumin, hyponatremia, and impaired exercise variables equally predicted clinical events in child and adult Fontan patients.

CONCLUSIONS

Distinctive differences in predictive value of clinical variables exist between child and adult Fontan patients. In addition to cardiac issues, we should consider non-cardiac determinents of clinical outcome to maximize our efforts to improve prognosis for adult Fontan survivors.

Pulmonary hypertension related to congenital heart disease: a call for action

Pulmonary arterial hypertension related to congenital heart disease (PAH-CHD) is a common type of pulmonary arterial hypertension (PAH). Despite this, little emphasis has been given to this group of patients until recently, when compared with idiopathic PAH. This is largely because of the complexity and the wide range of underlying cardiac anatomy and physiology, with a multitude of adaptive mechanisms not fully understood. Pulmonary arterial hypertension related to congenital heart disease is, therefore, best diagnosed and managed in centres specializing in both CHD and PAH, to avoid common pitfalls and old practices and to provide state-of-the-art care. We discuss the optimal management of PAH-CHD patients in a series of actions to be taken in order to optimize short- and long-term outcome, based on current knowledge of the condition and the advent of targeted advanced therapies.

Perioperative Outcomes of Major Noncardiac Surgery in Adults with Congenital Heart Disease

Background:

An increasing number of patients with congenital heart disease are surviving to adulthood. Consensus guidelines and expert opinion suggest that noncardiac surgery is a high-risk event, but few data describe perioperative outcomes in this population.

Methods:

By using the Nationwide Inpatient Sample database (years 2002 through 2009), the authors compared patients with adult congenital heart disease (ACHD) who underwent noncardiac surgery with a non-ACHD comparison cohort matched on age, sex, race, year, elective or urgent or emergency procedure, van Walraven comborbidity score, and primary procedure code. Mortality and morbidity were compared between the two cohorts.

Results:

A study cohort consisting of 10,004 ACHD patients was compared with a matched comparison cohort of 37,581 patients. Inpatient mortality was greater in the ACHD cohort (407 of 10,004 [4.1%] vs. 1,355 of 37,581 [3.6%]; unadjusted odds ratio, 1.13; P = 0.031; adjusted odds ratio, 1.29; P &lt; 0.001). The composite endpoint of perioperative morbidity was also more commonly observed in the ACHD cohort (2,145 of 10.004 [21.4%] vs. 6,003 of 37,581 [16.0%]; odds ratio, 1.44; P &lt; 0.001). ACHD patients comprised an increasing proportion of all noncardiac surgical admissions over the study period (P value for trend is &lt;0.001), and noncardiac surgery represented an increasing proportion of all ACHD admissions (P value for trend is &lt;0.001).

Conclusions:

Compared with a matched control cohort, ACHD patients undergoing noncardiac surgery experienced increased perioperative morbidity and mortality. Within the limitations of a retrospective analysis of a large administrative dataset, this finding demonstrates that this is a vulnerable population and suggests that better efforts are needed to understand and improve the perioperative care they receive.

[Intensive care management of critically ill adults with congenital heart disease]

Due to improvements in cardiac surgery and perioperative care the number of adults with congenital heart disease is continuously growing. The perioperative and intensive care management of these patients is a challenge due to the variety of pathologies and surgical options as well as the complex pathophysiology. Many patients develop organ dysfunction with time and many require multiple cardiac operations as well as non-cardiac interventions during adulthood. While these patients are best treated in dedicated tertiary centers that provide a multidisciplinary expertise, basic knowledge of this population is important for everyone involved in acute medical care. This review will discuss some general aspects of adults with congenital heart disease such as pulmonary hypertension, Eisenmenger syndrome, cyanosis, pregnancy and perioperative care, with a special focus on the management of critically ill patients.

Translational paradigms in scientific and clinical imaging of cardiac development

Congenital heart defects (CHD) are the most prevalent congenital disease, with 45% of deaths resulting from a congenital defect due to a cardiac malformation. Clinically significant CHD permit survival upon birth, but may become immediately life threatening. Advances in surgical intervention have significantly reduced perinatal mortality, but the outcome for many malformations is bleak. Furthermore, patients living while tolerating a CHD often acquire additional complications due to the long-term systemic blood flow changes caused by even subtle anatomical abnormalities. Accurate diagnosis of defects during fetal development is critical for interventional planning and improving patient outcomes. Advances in quantitative, multidimensional imaging are necessary to uncover the basic scientific and clinically relevant morphogenetic changes and associated hemodynamic consequences influencing normal and abnormal heart development. Ultrasound is the most widely used clinical imaging technology for assessing fetal cardiac development. Ultrasound-based fetal assessment modalities include motion mode (M-mode), two dimensional (2D), and 3D/4D imaging. These datasets can be combined with computational fluid dynamics analysis to yield quantitative, volumetric, and physiological data. Additional imaging modalities, however, are available to study basic mechanisms of cardiogenesis, including optical coherence tomography, microcomputed tomography, and magnetic resonance imaging. Each imaging technology has its advantages and disadvantages regarding resolution, depth of penetration, soft tissue contrast considerations, and cost. In this review, we analyze the current clinical and scientific imaging technologies, research studies utilizing them, and appropriate animal models reflecting clinically relevant cardiogenesis and cardiac malformations. We conclude with discussing the translational impact and future opportunities for cardiovascular development imaging research.

Clinical features of adult patients with Eisenmenger's syndrome in Japan and Korea

BACKGROUND

There are few articles on mortality and morbidity of adult patients with Eisenmenger's syndrome (ES) in the current era when disease targeting therapy (DTT) has been available.

METHODS AND RESULTS

198 patients (a median age 35 years, 64% female) with ES who visited the 16 participating institutes in Japan and Korea from 1998 to 2009 were enrolled. Clinical data during adulthood were collected from each institutional chart and analyzed centrally. During a median follow-up of 8 years, 30 patients died including 14 sudden deaths. 89 patients took oral medication of DTT and clinical improvement was observed in 54 of them. However, survival rate in patients taking DTT was not different from those without (87% vs 84%, p=0.55). When the clinical data in between first and last clinic visits were compared in 85 patients, the patients with NYHA >/=III increased from 24% to 48% (p<0.001), SpO2 decreased from 89% to 85% (p=0.008) and hematocrit increased from 51.4% to 52.9% (p=0.04). Non-survivors had poorer NYHA function class, lower body weight (BW), lower body mass index (BMI), and higher serum level of Cr at the first visits than survivors.

CONCLUSIONS

Long term survival and clinical status of adult patients with ES remains unsatisfactory even in the current era of DTT. Poor NYHA functional class, low BW, low BMI and high serum level of Cr were related to mortality. DTT therapy improved clinical status in many patients with Eisenmenger's syndrome, but no significant impact on survival could be shown.

Cyanotic nephropathy--a morphometric analysis

OBJECTIVE

Nephropathy is a known complication in cyanotic congenital heart disease (CCHD). This study was undertaken for an objective analysis of histopathological changes of cyanotic nephropathy at autopsy.

DESIGN

Retrospective case records studied.

SETTING

Tertiary care teaching hospital affiliated to medical college in Mumbai, India.

PATIENTS AND METHODS

The renal histopathological findings of 50 consecutive autopsies in patients with CCHD were compared with 25 age-matched controls. The Bowman's capsular, glomerular tuft, and hilar arteriolar diameters were measured morphometrically. Statistical analysis was performed using unpaired t-test. A P value equal to or less than .05 was considered significant.

RESULTS

Among the 50 autopsied cases of CCHD, there were 35 males and 15 females, with a mean age of 4.64 years. The renal changes observed were glomerulomegaly, glomerulosclerosis, periglomerular fibrosis, hyperplastic arteriolosclerosis, and interstitial fibrosis. The objectively measured parameters were higher in cases as compared with controls in all age groups, and further these were also found to be higher in patients having decreased pulmonary arterial blood flow than those having normal to increased pulmonary arterial blood flow. The difference in Bowman's capsular and glomerular tuft diameters was statistically significant in the neonates and children in the age groups, 1-5 years and above 10 years. The difference in hilar arteriolar diameter was statistically significant for all age groups except neonates.

CONCLUSION

Patients with CCHD show significant changes in the kidneys as assessed morphometrically, leading to renal dysfunction, and the age of the patients plays a role in their development.

Urine β 2-Microglobolin in the Patients with Congenital Heart Disease

BACKGROUND

This study aimed to evaluate the renal tubular function in the patients with congenital heart disease using β2-microglobulin.

METHODS

In this case-control study, based on oxymetry, the patients with congenital heart disease were divided into two groups of cyanotic (n=20) and acyanotic (n=20). Congenital heart disease was diagnosed by echocardiography. Healthy individuals within the same age and sex groups were used as controls. Na(+), β2-micro globulin, creatinine (Cr), and β2-microglobulin/Cr ratio were measured in random urine samples and the results were compared to the same parameters in the control group using Tukey, One-Way ANOVA, and X(2) tests.

RESULTS

Based on the study results, urine sodium in the patients with cyanotic heart disease was significantly different from that of the controls (P=0.023). The results also revealed a significant difference between the two groups with congenital heart disease regarding urine β2-microglobulin (P=0.045). In addition, the patients with cyanotic heart disease were significantly different from those with acyanotic heart disease and the controls regarding urine β2-micro globulin/Cr ratio (P=0.012 and P=0.026, respectively).

CONCLUSIONS

The results of this study demonstrated that renal tubular dysfunction began in the patients with congenital heart disease, especially in those with cyanotic congenital heart disease. Besides, early diagnosis before cardiac surgery leads to better control of renal tubular disease.

Extracardiac complications in adults with congenital heart disease

With the increasing number of adults living with repaired, or unrepaired, congenital heart disease, there is a growing incidence of extracardiac comorbidities. These comorbidities can affect various organ systems in complex ways, and may have a significant impact on a patient's quality of life and survival. Many of these potential complications may go undiagnosed until there is already a significant bearing on the patient's life. Therefore, it is important for physicians who care for the adult congenital patient to be mindful of these potential extracardiac complications, and actively assess for these complications in their adult congenital practice. Continued research to identify modifiable risk factors is needed so that both preventative and therapeutic management options for these extracardiac complications may be developed.

Abnormal Lung Function in Adults With Congenital Heart Disease: Prevalence, Relation to Cardiac Anatomy, and Association With Survival

Background—

Restrictive lung defects are associated with higher mortality in patients with acquired chronic heart failure. We investigated the prevalence of abnormal lung function, its relation to severity of underlying cardiac defect, its surgical history, and its impact on outcome across the spectrum of adult congenital heart disease.

Methods and Results—

A total of 1188 patients with adult congenital heart disease (age, 33.1±13.1 years) undergoing lung function testing between 2000 and 2009 were included. Patients were classified according to the severity of lung dysfunction based on predicted values of forced vital capacity. Lung function was normal in 53% of patients with adult congenital heart disease, mildly impaired in 17%, and moderately to severely impaired in the remainder (30%). Moderate to severe impairment of lung function related to complexity of underlying cardiac defect, enlarged cardiothoracic ratio, previous thoracotomy/ies, body mass index, scoliosis, and diaphragm palsy. Over a median follow-up period of 6.7 years, 106 patients died. Moderate to severe impairment of lung function was an independent predictor of survival in this cohort. Patients with reduced force vital capacity of at least moderate severity had a 1.6-fold increased risk of death compared with patients with normal lung function ( P =0.04).

Conclusions—

A reduced forced vital capacity is prevalent in patients with adult congenital heart disease; its severity relates to the complexity of the underlying heart defect, surgical history, and scoliosis. Moderate to severe impairment of lung function is an independent predictor of mortality in contemporary patients with adult congenital heart disease.

Heart transplantation in congenital heart disease: in whom to consider and when?

Due to impressive improvements in surgical repair options, even patients with complex congenital heart disease (CHD) may survive into adulthood and have a high risk of end-stage heart failure. Thus, the number of patients with CHD needing heart transplantation (HTx) has been increasing in the last decades. This paper summarizes the changing etiology of causes of death in heart failure in CHD. The main reasons, contraindications, and risks of heart transplantation in CHD are discussed and underlined with three case vignettes. Compared to HTx in acquired heart disease, HTx in CHD has an increased risk of perioperative death and rejection. However, outcome of HTx for complex CHD has improved over the past 20 years. Additionally, mechanical support options might decrease the waiting list mortality in the future. The number of patients needing heart-lung transplantation (especially for Eisenmenger's syndrome) has decreased in the last years. Lung transplantation with intracardiac repair of a cardiac defect is another possibility especially for patients with interatrial shunts. Overall, HTx will remain an important treatment option for CHD in the near future.

Renal function and injury in infants and young children with congenital heart disease

BACKGROUND

The aim of this study was to investigate renal function and injury in infants and young children with congenital heart disease (CHD).

METHODS

We prospectively enrolled 58 CHD children aged ≤3 years and 20 age-matched controls and divided these into four groups: Group I, acyanotic CHD (n = 24); Group II, cyanotic CHD with arterial oxygen saturation of >75 % (n = 20); Group III, cyanotic CHD with arterial oxygen saturation of ≤75 % (n = 14); Group IV, normal controls (n = 20). Urinary levels of microalbumin (MA), N-acetyl-ß-D-glucosaminidase (NAG), and α1-microglobulin (α1-MG) corrected by creatinine (UCr) were compared.

RESULTS

Children with CHD had elevated urinary α1-MG/UCr levels, with Group III children having the highest level. Groups I and III children had higher urinary NAG/UCr levels than those of Groups II and IV. Urinary MA/UCr levels in the three patient groups were comparable and significantly higher than that in the control group. A α1-MG × 100/ (α1-MG + MA) of <15 %, indicative of glomerular damage, was present in two patients in Group I and one in Group III, but none in Group II.

CONCLUSIONS

Tubular injury can occur in CHD patients during infancy and early childhood. Among our patient cohort, it was most prominent in children with severe cyanosis. Glomerular injury was detected in some individuals with advanced heart failure or severe cyanosis.

Renal dysfunction is common among adults after palliation for previous tetralogy of Fallot

Long-term survival after tetralogy of Fallot (TOF) repair is excellent. However, little is published regarding late noncardiac complications. This study aimed to determine the prevalence and risk factors for renal dysfunction among adults after TOF repair. For this study, 56 adult patients with complete repair of TOF were identified, and their charts were retrospectively reviewed. An estimated glomerular filtration rate (eGFR) for each patient was calculated using the Modification of Diet in Renal Disease formula (MDRD). Using each patient's eGFR, he or she was classified into stages based on the National Kidney Foundation chronic kidney disease (CKD) staging. Clinical parameters were compared among patients with and those without renal dysfunction to identify risk factors for renal impairment. The median estimated eGFR rate for the cohort was 78 ml/min/1.73 m(2). Based on the National Kidney Foundation CKD staging system, 54 % of the patients had at least stage 2 chronic renal disease. The risk factors identified were hypertension (p < 0.01), type 2 diabetes mellitus (p < 0.05), longer follow-up evaluation (p < 0.005), older age at complete repair (p < 0.05), and use of daily diuretics (p < 0.05). After repair of TOF, renal dysfunction is common at late follow-up evaluation. The study findings show the importance of routine assessment of renal function and the need to limit or avoid future episodes of acute kidney injury in this at-risk population.

Congenital heart disease and pulmonary hypertension

Many patients with congenital heart disease and systemic-to-pulmonary shunts develop pulmonary arterial hypertension (PAH), particularly if the cardiac defect is left unrepaired. A persistent increase in pulmonary blood flow may lead to obstructive arteriopathy and increased pulmonary vascular resistance, a condition that can lead to reversal of shunt and cyanosis (Eisenmenger syndrome). Cardiac catheterization is crucial to confirm diagnosis and facilitate treatment. Bosentan is the only medication to date to be compared with placebo in a randomized controlled trial specifically targeting congenital heart disease-associated PAH. Lung transplantation with repair of the cardiac defect or combined heart-lung transplantation is reserved for recalcitrant cases.

Echocardiographic Predictors of Outcome in Eisenmenger Syndrome

Background—

Eisenmenger syndrome differs significantly from other types of pulmonary arterial hypertension in its physiology and prognosis. We sought to assess the relationship between the echocardiographic characteristics of patients with Eisenmenger syndrome and mortality.

Methods and Results—

Clinical and echocardiographic variables were assessed in 181 consecutive patients with Eisenmenger syndrome, excluding those with complex congenital heart disease. Patients' mean age was 39.1±12.8 years, 59 (32.6%) were male, 122 (67.4%) were in functional class III or higher, and 74 (40.9%) were on advanced therapies. Mean oxygen saturation at rest was 85.1±7.8%, and median B-type natriuretic peptide was 55.4 ng/L. Over a median follow-up of 16.4 months, 19 patients died; the strongest predictors of mortality were tricuspid annular plane systolic excursion and peak systolic velocity, myocardial performance (expressed as total isovolumic time and ratio of systolic to diastolic duration), and elevated central venous pressure (expressed as right atrial [RA] area, RA pressure, and ratio of RA to left atrial area), even after we accounted for advanced therapies. A composite score based on the strongest echocardiographic predictors of outcome, including 1 point for each of the following: tricuspid annular plane systolic excursion <15 mm, ratio of right ventricular effective systolic to diastolic duration ≥1.5, RA area ≥25 cm 2 , ratio of RA to left atrial area ≥1.5, was highly predictive of clinical outcome (area under the curve 0.90±0.01), with no improvement when B-type natriuretic peptide and resting saturations were added into the model.

Conclusions—

Echocardiographic parameters of right ventricular function and RA area predict mortality in Eisenmenger patients. A new composite echocardiographic score, described herewith, may be incorporated into the noninvasive, periodic assessment of these patients.

Heart transplantation in adults with end-stage congenital heart disease

Residual abnormalities in cardiac structure and function predispose adults with congenital heart disease to late-onset heart failure and its complications. Evaluation of this population requires collaboration between adult congenital and heart failure specialists. In addition to assessing heart transplant eligibility, clinicians must balance the risks of premature listing against progressive heart failure and increased waiting list mortality. Following heart transplantation, adults with congenital heart disease have higher mortality due to an increased risk of bleeding, infection and donor right heart failure secondary to pulmonary hypertension. Concerns relating to increased early mortality should be balanced against superior long-term survival in adult congenital heart disease patients surviving beyond the first year after heart transplantation.

Urinary interleukin-18 and urinary neutrophil gelatinase-associated lipocalin predict acute kidney injury following pulmonary valve replacement prior to serum creatinine

BACKGROUND

It is becoming increasingly recognized that manifestations of congenital heart disease (CHD) extend beyond the cardiovascular system. The factors contributing to renal dysfunction in patients with CHD are multifactorial, with acute kidney injury (AKI) at time of cardiac surgery playing a major role. AKI is often diagnosed based on changes in serum creatinine and estimated glomerular filtration rate (eGFR). Such measurements are often late and imprecise. Recent data indicate that urinary biomarkers interleukin-18 (IL-18) and neutrophil gelatinase-associated lipocalin (NGAL) are earlier markers of AKI. We sought to determine the efficacy of urinary IL-18 and NGAL for detecting early AKI in patients undergoing surgical pulmonary valve replacement (PVR).

METHODS

Twenty patients presenting for surgical PVR with a history of previous repair of a conotruncal anomaly were enrolled. Preoperative clinical data were measured and urine samples and serum creatinine were collected at 6, 12, 24, and 72 hours post bypass. Urine was evaluated for NGAL and IL-18. AKI was determined using the Risk, Injury, Failure, Loss and End Stage Renal Disease (RIFLE) classification system.

RESULTS

Using the RIFLE classification system, seven patients (35%) were found to have AKI defined as a drop in the eGFR or an increase in serum creatinine. All seven patients with AKI had marked increase from preoperative baseline in urine IL-18 (sixfold) and NGAL (26-fold). Using NGAL and IL-18, AKI was detected at 6 hours postoperatively, resulting in AKI being identified 12-36 hours prior to detection by conventional methods. No preoperative predictors for AKI were identified.

CONCLUSION

Both NGAL and IL-18 are early predictive biomarkers of AKI, and both increase in tandem after surgical PVR. Importantly, both rise before an increase in creatinine or a decrease in eGFR is present. Monitoring both biomarkers may allow for earlier detection and subsequent interventions to prevent AKI at time of surgery for CHD.

New York Heart Association class assessment by cardiologists and outpatients with congenital cardiac disease: a head-to-head comparison of three patient-based versions

BACKGROUND

The objective of this study was to compare three patient-based New York Heart Association assessments with cardiologist assessments in outpatients with congenital cardiac disease.

METHODS

Consecutive adult outpatients completed three questionnaires in a random order: a patient-based translation of the New York Heart Association classes, a self-constructed questionnaire based on the New York Heart Association classes, and the Specific Activity Scale. The treating cardiologist assessed the New York Heart Association class on the same day. Patient-cardiologist agreement was assessed by calculating percent agreement and weighted kappa. We also explored the level of agreement for patients without co-morbidity.

RESULTS

In all, 86 adults--with a median age of 35.8 years--including 46 women participated. An agreement of 75.6% (weighted kappa is 0.43; probability is smaller than 0.01), 70.6% (weighted kappa is 0.44; probability is smaller than 0.01), and 74.4% (weighted kappa is 0.28; probability is smaller than 0.01) was found between the cardiologist assessment and the patient-based translation, self-constructed questionnaire, and the Specific Activity Scale, respectively. The patient-based translation equally over- and underestimated the New York Heart Association class, whereas the self-constructed questionnaire overestimated and the Specific Activity Scale underestimated the New York Heart Association class. Agreement levels for patients without co-morbidity were higher than agreement levels for the total group.

CONCLUSION

The patient-based translation yielded adequate agreement with cardiologist-assessed New York Heart Association class, showed equal over- and underestimation, and was easy to complete. The patient-based translation with the instruction to only consider functional impairments caused by the congenital cardiac defect is recommended in future studies of outpatients with congenital cardiac disease.

Independent risk factors for cardiac operations in adults with congenital heart disease: a retrospective study of 543 operations for 500 patients

Adults with congenital heart disease (CHD) are an increasing population requiring cardiac operations. To date, the perioperative risk factors for this group have not been identified. This study aimed to identify clinical, morphologic, and hemodynamic risk factors for an adverse outcome. This study retrospectively analyzed a cohort of 500 patients (ages >16 years) who underwent 543 operations between January 2004 and December 2008 at a single center. The composite end point of an adverse outcome was in-hospital death, a prolonged intensive care exceeding 4 days, or both. The composite end point was reached by 253 of the patients (50.6%). Of the 500 patients, 13 (2.6%) died within 30 days after the operation. After logistic regression analysis, the following eight items remained significant: male gender (P = 0.003; odds ratio [OR] 1.8; 95% confidence interval [CI] 1.2-2.6), cyanosis (P > 0.006; OR 3.7; 95% CI 1.5-9.4), functional class exceeding 2 (P = 0.004; OR 2.2; 95% CI 1.3-3.7), chromosomal abnormalities (P = 0.004; OR 3.3; 95% CI 1.4-7.7), impaired renal function (P = 0.019; OR 3.8; 95% CI 1.2-11.5), systemic right ventricle (RV) in a biventricular circulation (P = 0.027; OR 3.3; 95% CI 1.1-9.5), enlargement of the systemic ventricle (P = 0.011; OR 1.7; 95% CI 1.1-2.6), and operation with extracorporeal circulation (P = 0.002; OR 4.3; 95% CI 1.7-11.4). Early mortality in the current adult CHD population is low. Morbidity, however, is significant and influenced by the patients' conditions (male gender, chromosomal abnormalities), history (cyanosis, New York Hospital Association [NYHA] class), and underlying morphology (systemic RV). This information for a large cohort of patients could help progress toward more adequate counseling for adults with a congenital heart defect.

The Adult Patient with Eisenmenger Syndrome: A Medical Update after Dana Point Part III: Specific Management and Surgical Aspects

Eisenmenger syndrome is the most severe form of pulmonary arterial hypertension and arises on the basis of congenital heart disease with a systemic-to-pulmonary shunt. Due to the chronic slow progressive hypoxemia with central cyanosis, adult patients with the Eisenmenger syndrome suffer from a complex and multisystemic disorder including coagulation disorders (bleeding complications and paradoxical embolisms), renal dysfunction, hypertrophic osteoarthropathy, heart failure, reduced quality of life and premature death.

For a long time, therapy has been limited to symptomatic options or lung or combined heart-lung transplantation. As new selective pulmonary vasodilators have become available and proven to be beneficial in various forms of pulmonary arterial hypertension, this targeted medical treatment has been expected to show promising effects with a delay of deterioration also in Eisenmenger patients. Unfortunately, data in Eisenmenger patients suffer from small patient numbers and a lack of randomized controlled studies.

To optimize the quality of life and the outcome, referral of Eisenmenger patients to spezialized centers is required. In such centers, specific interdisciplinary management strategies of physicians specialized on congenital heart diseases and PAH should be warranted.

This medical update emphasizes the current diagnostic and therapeutic options for Eisenmenger patients with particularly focussing on specific management and surgical aspects.

Long-term serial aerobic exercise capacity and hemodynamic properties in clinically and hemodynamically good, "excellent", Fontan survivors

BACKGROUND

The serial hemodynamics and predictors of long-term, good Fontan survivors remain unknown.

METHODS AND RESULTS

Two hundred one patients who had undergone a Fontan operation before September 1998 were reviewed to compare their long-term clinical status with serial hemodynamics. During a mean follow-up of 18.7 years, 47 (30.1%) of the 156 survivors had no clinical events that required an unscheduled hospitalization. Of those, 18 survivors exhibited good serial hemodynamics and the respective mean values of central venous pressure (CVP, mmHg), cardiac index (CI, L·min(-1)·m(2)), and ventricular ejection fraction (EF, %) before and 1, 5, 10, and 15 years after the operation were as follows: 3.8, 9.0, 11.3, 10.6, and 10.1 (CVP); 3.6, 3.1, 2.8, 2.6, and 2.6, and 69 (CI); 57, 56, 58, 54, and 53 (EF). Serial values of CVP, ventricular end-diastolic pressure (EDP) and the grade of atrioventricular valve regurgitation (AVVR) were lower and the peak oxygen uptake was greater in the good patients (P<0.05 for all). A 1-year postoperative lower CVP and no history of AVVR repair during the Fontan operation independently predicted the good patients (P<0.05).

CONCLUSIONS

A lower CVP and EDP, better atrioventricular valvular function, and greater exercise capacity characterize good Fontan survivors and an early postoperative low CVP without an AVVR repair predicts good survivors.

Incidence, risk factors, and outcomes of acute kidney injury after pediatric cardiac surgery: a prospective multicenter study

OBJECTIVE

To determine the incidence, severity, and risk factors of acute kidney injury in children undergoing cardiac surgery for congenital heart defects.

DESIGN

Prospective observational multicenter cohort study.

SETTING

Three pediatric intensive care units at academic centers.

PATIENTS

Three hundred eleven children between the ages of 1 month and 18 yrs undergoing pediatric cardiac surgery.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Acute kidney injury was defined as a ≥50% increase in serum creatinine from the preoperative value. Secondary outcomes were length of mechanical ventilation, length of intensive care unit and hospital stays, acute dialysis, and in-hospital mortality. The cohort had an average age of 3.8 yrs and was 45% women and mostly white (82%). One-third had prior cardiothoracic surgery, 91% of the surgeries were elective, and almost all patients required cardiopulmonary bypass. Acute kidney injury occurred in 42% (130 patients) within 3 days after surgery. Children ≥2 yrs old and <13 yrs old had a 72% lower likelihood of acute kidney injury (adjusted odds ratio: 0.28, 95% confidence interval: 0.16, 0.48), and patients 13 yrs and older had 70% lower likelihood of acute kidney injury (adjusted odds ratio: 0.30, 95% confidence interval: 0.10, 0.88) compared to patients <2 yrs old. Longer cardiopulmonary bypass time was linearly and independently associated with acute kidney injury. The development of acute kidney injury was independently associated with prolonged ventilation and with increased length of hospital stay.

CONCLUSIONS

Acute kidney injury is common after pediatric cardiac surgery and is associated with prolonged mechanical ventilation and increased hospital stay. Cardiopulmonary bypass time and age were independently associated with acute kidney injury risk. Cardiopulmonary bypass time may be a marker for case complexity.