Vivan J.M. Baggen

Prognostic Value of N-Terminal Pro-B-Type Natriuretic Peptide, Troponin-T, and Growth-Differentiation Factor 15 in Adult Congenital Heart Disease

Background: The number of patients with adult congenital heart disease (ACHD) is rapidly increasing. To optimize patient management, there is a great need to accurately identify high-risk patients. Still, no biomarker has been firmly established as a clinically useful prognostic tool in this group. We studied the association of N-terminal pro-B-type natriuretic peptide (NT-proBNP), high-sensitive troponin-T, and growth-differentiation factor 15 with cardiovascular events in ACHD. Methods: Clinically stable patients with ACHD who routinely visited the outpatient clinic between April 2011 and April 2013 underwent clinical assessment, electrocardiography, echocardiography, and biomarker measurement (NT-proBNP, high-sensitive troponin-T, and growth-differentiation factor 15) at the time of study inclusion. Patients were prospectively followed for the occurrence of cardiovascular events (death, heart failure, hospitalization, arrhythmia, thromboembolic events, and reintervention). Survival curves were derived by the Kaplan-Meier method, and Cox regression was performed to investigate the relation between biomarkers and events with adjustment for multiple clinical and echocardiographic variables. Results: In total, 595 patients were included (median age, 33 years; interquartile range, 25–41 years; 58% male; 90% New York Heart Association class I). Patients were followed during a median of 42 (interquartile range, 37–46) months. Of the 3 evaluated biomarkers, NT-proBNP in the upper quartile (>33.3 pmol/L) was most strongly associated with cardiovascular events (n=165, adjusted hazard ratio, 9.05 [3.24–25.3], P<0.001) and with death or heart failure (n=50, adjusted hazard ratio, 16.0 [2.04–126], P<0.001). When NT-proBNP was analyzed as a continuous variable, similar findings were retrieved. The cumulative proportion of patients with death and heart failure was only 1% in the lowest 2 NT-proBNP quartiles. Elevated NT-proBNP (>14 pmol/L), elevated high-sensitive troponin-T (>14 ng/L), and elevated growth-differentiation factor 15 (>1109 ng/L) identified those patients at highest risk of cardiovascular events (log-rank P<0.0001). Conclusions: NT-proBNP provides prognostic information beyond a conventional risk marker model in patients with ACHD and can reliably exclude the risk of death and heart failure. Elevated levels of NT-proBNP, high-sensitive troponin-T, and growth-differentiation factor 15 identify patients at highest risk of cardiovascular events. These biomarkers therefore may play an important role in the monitoring and management of patients with ACHD.

Release of growth-differentiation factor 15 and associations with cardiac function in adult patients with congenital heart disease ☆

BACKGROUND Growth-differentiation factor-15 (GDF-15), a cytokine with broad cardiac and non-cardiac activity, has diagnostic and prognostic value in various diseases, including heart failure. We aimed to investigate the release of GDF-15 in adults with congenital heart disease (ConHD), and assess the association with cardiac function and functional capacity. METHODS A total of 587 consecutive adults with ConHD (median age 33 [IQR 25-41] years, 59% men, and 90% NYHA I) underwent electrocardiography, echocardiography, venepuncture and were seen by a cardiologist. A subset of 143 patients underwent bicycle ergometry on the same day. RESULTS Median plasma GDF-15 was 618 [IQR 487-867] ng/L. In 87 patients (15%), GDF-15 was above the reference value of normal (1109 ng/L). GDF-15 levels were higher in older patients (r=0.367, p<0.001). GDF-15 was higher in patients with elevated pulmonary pressure (median 1114 [IQR 796-2320 ng/L) than in patients with normal pulmonary pressure (median 606 [IQR 481-826] ng/L, p<0.001). GDF-15 correlated positively with NT-proBNP (r=0.445, p<0.001). In multivariate analysis adjusting for age, sex, and NT-proBNP, hs-TnT and hs-CRP, GDF-15 above the reference value was associated with NYHA class (odds ratio for NYHA≥II: 3.5 [95% CI 1.8-6.8], p<0.001), and decreased exercise capacity (odds ratio for workload >85%:0.2 [95% CI 0.06-0.8], p=0.018), but not with systolic ventricular function or ECG rhythm. CONCLUSIONS GDF-15 is elevated in a substantial number of patients and higher in those with elevated pulmonary pressures, regardless of underlying congenital diagnosis. GDF-15 is associated with NYHA class, NT-proBNP and exercise capacity, suggesting the marker has diagnostic and potential prognostic value in adults with ConHD.

Transthoracic 3D echocardiographic left heart chamber quantification in patients with bicuspid aortic valve disease

Integration of volumetric heart chamber quantification by 3D echocardiography into clinical practice has been hampered by several factors which a new fully automated algorithm (Left Heart Model, (LHM)) may help overcome. This study therefore aims to evaluate the feasibility and accuracy of the LHM software in quantifying left atrial and left ventricular volumes and left ventricular ejection fraction in a cohort of patients with a bicuspid aortic valve. Patients with a bicuspid aortic valve were prospectively included. All patients underwent 2D and 3D transthoracic echocardiography and computed tomography. Left atrial and ventricular volumes were obtained using the automated program, which did not require manual contour detection. For comparison manual and semi-automated measurements were performed using conventional 2D and 3D datasets. 53 patients were included, in four of those patients no 3D dataset could be acquired. Additionally, 12 patients were excluded based on poor imaging quality. Left ventricular end-diastolic and end-systolic volumes and ejection fraction calculated by the LHM correlated well with manual 2D and 3D measurements (Pearson’s r between 0.43 and 0.97, p < 0.05). Left atrial volume (LAV) also correlated significantly although LHM did estimate larger LAV compared to both 2DE and 3DE (Pearson’s r between 0.61 and 0.81, p < 0.01). The fully automated software works well in a real-world setting and helps to overcome some of the major hurdles in integrating 3D analysis into daily practice, as it is user-independent and highly reproducible in a group of patients with a clearly defined and well-studied valvular abnormality.

Main pulmonary artery area limits exercise capacity in patients long-term after arterial switch operation

OBJECTIVES Despite excellent survival in patients after the arterial switch operation, reintervention is frequently required and exercise capacity is decreased in a substantial number of patients. This study relates right-sided imaging features in patients long-term after the arterial switch operation to exercise capacity and ventilatory efficiency to investigate which lesions are functionally important. METHODS Patients operated in the UMC Utrecht, the Netherlands (1976-2001) and healthy controls underwent cardiac magnetic resonance imaging and cardiopulmonary exercise testing within 1 week. We measured main, left, and right pulmonary artery cross-sectional areas, pulmonary blood flow distribution, peak oxygen uptake, and minute ventilation relative to carbon dioxide elimination. RESULTS A total of 71 patients (median age, 20 [12-35] years, 73% were male) and 21 healthy controls (median age, 26 [21-35] years, 48% were male) were included. Main, left, and right pulmonary artery areas were decreased compared with controls (190 vs 269 mm(2)/m(2), 59 vs 157 mm(2)/m(2), 98 vs 139 mm(2)/m(2), respectively, all P < .001); however, pulmonary blood flow distribution was comparable (P = .722). Peak oxygen uptake and minute ventilation relative to carbon dioxide elimination were 88% ± 20% and 23.7 ± 3.8, respectively, with 42% and 1% of patients demonstrating abnormal results (≤ 84% and ≥ 34, respectively). The main pulmonary artery area significantly correlated with peak oxygen uptake (r = 0.401, P = .001) and pulmonary blood flow distribution with minute ventilation relative to carbon dioxide elimination (r = -0.329, P = .008). Subanalysis (<18, 18-25, >25 years) showed that the main pulmonary artery area was smaller in older age groups. In multivariable analysis, the main pulmonary artery area was independently associated with peak oxygen uptake (P = .032). CONCLUSIONS In adult patients after the arterial switch operation, narrowing of the main pulmonary artery is a common finding and is the main determinant of limitation in functional capacity, rather than pulmonary branch stenosis.

Prognostic value of galectin-3 in adults with congenital heart disease

Objective Galectin-3 is an emerging biomarker for risk stratification in patients with heart failure. This study aims to investigate the release of galectin-3 and its association with cardiovascular events in patients with adult congenital heart disease (ACHD). Methods In this prospective cohort study, 602 consecutive patients with ACHD who routinely visited the outpatient clinic were enrolled between 2011 and 2013. Galectin-3 was measured in thaw serum by batch analysis. The association between galectin-3 and a primary endpoint of all-cause mortality, heart failure, hospitalisation, arrhythmia, thromboembolic events and cardiac interventions was investigated using multivariable Cox models. Reference values and reproducibility were established by duplicate galectin-3 measurements in 143 healthy controls. Results Galectin-3 was measured in 591 (98%) patients (median age 33 (25–41) years, 58% male, 90% New York Heart Association (NYHA) class I). Median galectin-3 was 12.7 (range 4.2–45.7) ng/mL and was elevated in 7% of patients. Galectin-3 positively correlated with age, cardiac medication use, NYHA class, loss of sinus rhythm, cardiac dysfunction and N-terminal pro-B-type natriuretic peptide (NT-proBNP). During a median follow-up of 4.4 (IQR 3.9–4.8) years, the primary endpoint occurred in 195 patients (33%). Galectin-3 was significantly associated with the primary endpoint in the univariable analysis (HR per twofold higher value 2.05; 95% CI 1.44 to 2.93, p<0.001). This association was negated after adjustment for NT-proBNP (HR 1.04; 95% CI 0.72 to 1.49, p=0.848). Conclusions Galectin-3 is significantly associated with functional capacity, cardiac function and adverse cardiovascular events in patients with ACHD. Nevertheless, the additive value of galectin-3 to a more conventional risk marker such as NT-proBNP seems to be limited.

Prognostic value of left atrial size and function in adults with tetralogy of Fallot

BACKGROUND Left atrial (LA) size predicts cardiovascular outcome in chronic heart failure. Its prognostic value in adults with repaired tetralogy of Fallot (ToF) is unknown. This study therefore investigated the association of LA size and function with cardiovascular events in adults with ToF. METHODS Clinically stable adults with ToF who visited the outpatient clinic between 2011 and 2013 underwent echocardiography and were prospectively followed for the occurrence of death, heart failure, hospitalizations, arrhythmia, thromboembolic events, and re-interventions. LA maximal, minimal and pre-A wave volume, area and length were measured on the apical four-chamber view. Total, passive and active emptying fractions were calculated. RESULTS In total, 134 patients were included (median age 35 [IQR 29-45] years, 65% male, 91% NYHA I). Median follow-up was 40 [IQR 32-47] months. Patients with a dilated LA (≥34mL/m2, 43%) were at higher risk of cardiovascular events (n=33, adjusted HR 2.48 [1.09-5.62], P=0.030). Analysis of LA volumes as continuous variables yielded similar conclusions. In addition, LA length (adjusted HR 2.49 [1.51-4.09], P<0.001), total emptying fraction (adjusted HR 0.96 [0.93-0.99], P=0.008), and active emptying fraction (adjusted HR 0.92 [0.87-0.96], P=0.001) were significantly associated with cardiovascular events. Standardized HRs indicated that LA length was the strongest prognostic marker. In addition, none of the patients with a normally sized LA died or developed heart failure. CONCLUSIONS LA size and function can provide relevant prognostic information in clinically stable adults with repaired ToF. Especially LA length may be a valuable additional tool in the risk stratification of these patients.

Matrix metalloproteinases as candidate biomarkers in adults with congenital heart disease.

Abstract Context Matrix metalloproteinases (MMPs) are associated with diastolic dysfunction and heart failure in acquired heart disease. Objective To investigate the role of MMPs as novel biomarkers in clinically stable adults with congenital heart disease. Methods We measured serum MMP-2, -3, -9 and tissue inhibitor of matrix metalloproteinase-1 in 425 patients and analysed the association with cardiac function and exercise capacity. Results MMP-2 was significantly associated with exercise capacity, ventilatory efficiency and left ventricular deceleration time, independently of age, sex, body surface area and NT-proBNP. Conclusion MMP-2 may provide new information in the clinical evaluation of adults with congenital heart disease.

Red cell distribution width in adults with congenital heart disease: A worldwide available and low-cost predictor of cardiovascular events

BACKGROUND Red cell distribution width (RDW) is a standard component of the automated blood count, and is of prognostic value in heart failure and coronary heart disease. We investigated the association between RDW and cardiovascular events in patients with adult congenital heart disease (ACHD). METHODS AND RESULTS In this prospective cohort study, 602 consecutive patients with ACHD who routinely visited the outpatient clinic were enrolled between 2011 and 2013. RDW was measured in fresh venous blood samples at inclusion in 592 patients (median age 33 [IQR 25-41] years, 58% male, 90% NYHA I) and at four annual follow-up visits. During 4.3 [IQR 3.8-4.7] years of follow-up, the primary endpoint (death, heart failure, hospitalization, arrhythmia, thromboembolic events, cardiac intervention) occurred in 196 patients (33%). Median RDW was 13.4 (12.8-14.1)% versus 12.9 (12.5-13.4)% in patients with and without the primary endpoint (P < 0.001). RDW was significantly associated with the endpoint when adjusted for age, sex, clinical risk factors, CRP, and NT-proBNP (HR 1.20; 95% CI 1.06-1.35; P = 0.003). The C-index of the model including RDW was slightly, but significantly (P = 0.005) higher than the model without (0.74, 95% CI 0.70-0.78 versus 0.73, 95% CI 0.69-0.78). Analysis of repeated RDW measurements (n = 2449) did not show an increase in RDW prior to the occurrence of the endpoint. CONCLUSIONS RDW is associated with cardiovascular events in patients with ACHD, independently of age, sex, clinical risk factors, CRP, and NT-proBNP. This readily available biomarker could therefore be considered as an additive biomarker for risk stratification in these patients.

Prognostic Value of Serial N‐Terminal Pro‐B‐Type Natriuretic Peptide Measurements in Adults With Congenital Heart Disease

Background A single NT‐proBNP (N‐terminal pro‐B‐type natriuretic peptide) measurement is a strong prognostic factor in adult congenital heart disease. This study investigates NT‐proBNP profiles within patients with adult congenital heart disease and relates these to cardiovascular events. Methods and Results In this prospective cohort, 602 patients with adult congenital heart disease were enrolled at the outpatient clinic (years 2011–2013). NT‐proBNP was measured at study inclusion in 595 patients (median age 33 [IQR 25–41] years, 58% male, 90% NYHA I) and at subsequent annual visits. The primary end point was defined as death, heart failure, hospitalization, arrhythmia, thromboembolic event, or cardiac intervention; the secondary end point as death or heart failure. Repeated measurements were analyzed using linear mixed models and joint models. During a median follow‐up of 4.4 [IQR 3.8–4.8] years, a total of 2424 repeated measurements were collected. Average NT‐proBNP increase was 2.9 pmol/L the year before the primary end point (n=199, 34%) and 18.2 pmol/L before the secondary end point (n=58, 10%), compared with 0.3 pmol/L in patients who remained end point‐free (P‐value for difference in slope 0.006 and <0.001, respectively). In patients with elevated baseline NT‐proBNP (>14 pmol/L, n=315, 53%), repeated measurements were associated with the primary end point (HR per 2‐fold higher value 2.08; 95% CI 1.31–3.87; P<0.001) and secondary end point (HR 2.47; 95% CI 1.13–5.70; P=0.017), when adjusted for the baseline measurement. Conclusions NT‐proBNP increased before the occurrence of events, especially in patients who died or developed heart failure. Serial NT‐proBNP measurements could be of additional prognostic value in the annual follow‐up of patients with adult congenitive heart disease with an elevated NT‐proBNP.

Development and validation of a risk prediction model in patients with adult congenital heart disease

AIMS To develop and validate a clinically useful risk prediction tool for patients with adult congenital heart disease (ACHD). METHODS AND RESULTS A risk model was developed in a prospective cohort of 602 patients with moderate/complex ACHD who routinely visited the outpatient clinic of a tertiary care centre in the Netherlands (2011-2013). This model was externally validated in a retrospective cohort of 402 ACHD patients (Czech Republic, 2004-2013). The primary endpoint was the 4-year risk of death, heart failure, or arrhythmia, which occurred in 135 of 602 patients (22%). Model development was performed using multivariable logistic regression. Model performance was assessed with C-statistics and calibration plots. Of the 14 variables that were selected by an expert panel, the final prediction model included age (OR 1.02, 95%CI 1.00-1.03, p = 0.031), congenital diagnosis (OR 1.52, 95%CI 1.03-2.23, p = 0.034), NYHA class (OR 1.74, 95%CI 1.07-2.84, p = 0.026), cardiac medication (OR 2.27, 95%CI 1.56-3.31, p < 0.001), re-intervention (OR 1.41, 95%CI 0.99-2.01, p = 0.060), BMI (OR 1.03, 95%CI 0.99-1.07, p = 0.123), and NT-proBNP (OR 1.63, 95%CI 1.45-1.84, p < 0.001). Calibration-in-the-large was suboptimal, reflected by a lower observed event rate in the validation cohort (17%) than predicted (36%), likely explained by heterogeneity and different treatment strategies. The externally validated C-statistic was 0.78 (95%CI 0.72-0.83), indicating good discriminative ability. CONCLUSION The proposed ACHD risk score combines six readily available clinical characteristics and NT-proBNP. This tool is easy to use and can aid in distinguishing high- and low-risk patients, which could further streamline counselling, location of care, and treatment in ACHD.