Right ventricular dilatation score: a new assessment to right ventricular dilatation in adult patients with repaired tetralogy of Fallot

BACKGROUND

Patients with repaired tetralogy of Fallot (rTOF) experience long-term chronic pulmonary valve regurgitation resulting in right ventricular (RV) dilatation. According to current guidelines, the evaluation of patients with rTOF for RV dilatation should be based on cardiac magnetic resonance (CMR). However, for many asymptomatic patients, routine CMR is not practical. Our study aims to identify screening methods for CMR based on echocardiographic data, with the goal of establishing a more practical and cheap method of screening for severity of RV dilatation in patients with asymptomatic rTOF.

METHODS

Thirty two rTOF patients (mean age, 21(10.5) y, 21 males) with moderate to severe pulmonary regurgitation (PR) were prospectively recruited. Each patient received CMR and echocardiogram examination within 1 month prior to operation and collected clinical data, and then received echocardiogram examination at discharge and 3-6 months post-surgery.

RESULTS

RV moderate-severe dilatation was defined as right ventricular end-diastolic volume index (RVEDVI) ≥ 160 ml/m2 or right ventricular end-systolic volume index (RVESVI) ≥ 80 ml/m2 in 15 of 32 patients (RVEDVI, 202.15[171.51, 252.56] ml/m2, RVESVI, 111.99 [96.28, 171.74] ml/m2). The other 17 (RVESDI, 130.19 [117.91, 139.35] ml/m2, RVESVI = 67.91 [63.35, 73.11] ml/m2) were defined as right ventricle mild dilatation, i.e., RVEDVI < 160 ml/m2 and RVESVI < 80 ml/m2, and the two parameters were higher than normal values. Compared with the RV mild dilatation group, patients of RV moderate-severe dilatation have worse cardiac function before surgery (right ventricular ejection fraction, 38.92(9.19) % versus 48.31(5.53) %, p < 0.001; Left ventricular ejection fraction, 59.80(10.26) versus 66.41(4.15), p = 0.021). Patients with RV moderate-severe dilatation faced longer operation time and more blood transfusion during operation (operation time, 271.53(08.33) min versus 170.53(72.36) min, p < 0.01; Intraoperative blood transfusion, 200(175) ml versus 100(50) ml, p = 0.001). Postoperative RV moderate-severe dilatation patients have poor short-term prognosis, which was reflected in a longer postoperative hospital stay (6.59 [2.12] days versus 9.80 [5.10] days, p = 0.024) and a higher incidence of hypohepatia (0[0] % versus 4[26.7] %, p = 0.023). Patients with RV dilatation score > 2.35 were diagnosed with RV moderate-severe dilatation (AUC = 0,882; Sensitivity = 94.1%; Specificity = 77.3%).

CONCLUSIONS

RV moderate-severe dilatation is associated with worse preoperative cardiac function and short-term prognosis after PVR in rTOF patients with moderate to severe PR. The RV dilatation score is an effective screening method. When RV dilatation score > 2.35, the patient is indicated for further CMR examination and treatment.

Biomarkers, Socioeconomic Factors, and Right Ventricular Function After Surgical Repair for Tetralogy of Fallot

Right ventricular (RV) dysfunction early after tetralogy of Fallot (TOF) increases post-operative morbidity. We investigated associations of circulating biomarkers and socioeconomic factors with early post-operative RV systolic function. Single-center prospective cohort study of infants undergoing TOF repair. Six serologic biomarkers of myocardial fibrosis and wall stress collected at the time of surgery were measured with immunoassay. Geocoding was performed for socioeconomic factors. Multivariate adaptive regression splines (MARS) models identified factors associated with RV function parameters: fractional area change (FAC), global longitudinal strain and strain rate, and free wall strain and strain rate. Seventy-one patients aged 3.5 months (IQR 2.4, 5.2) were included. Galectin-3 was the highest ranked predictor for FAC, global longitudinal strain, and free wall strain, and procollagen type-I carboxy-terminal propeptide (PICP) was the highest ranked predictor for global longitudinal strain rate and free wall strain rate. Several neighborhood characteristics were also highly ranked. Models adjusted R² ranged from 0.71 to 0.85 (FAC, global longitudinal strain/strain rate), and 0.55-0.57 (RV free wall strain/strain rate). A combination of serologic biomarkers, socioeconomic, and clinical variables explain a significant proportion of the variability in RV function after TOF repair. These factors may inform pre-operative risk-stratification for these patients.

Comparison of serum biomarkers of myocardial fibrosis with cardiac magnetic resonance in patients operated for tetralogy of Fallot

BACKGROUND

Serum biomarkers of myocardial fibrosis are considered markers of adverse outcome in adults with heart disease. Associations between biomarkers and clinical parameters in tetralogy of Fallot (TOF) has been understudied. We compared serum biomarker profiles with clinical and cardiac magnetic resonance (CMR) parameters of ventricular remodeling in patients with repaired TOF.

METHODS

Serum biomarkers [metalloproteinases MMP1 and MMP9, galectin-3, micro-RNA21 (miR21)), ST2, procollagen type I carboxy-terminal propeptide (PICP), and NTproBNP] were measured in TOF patients undergoing CMR. Associations between biomarkers and clinical and CMR variables were assessed using correlation coefficients, and linear and logistic regression.

RESULTS

Sixty patients were investigated, of which 47% were male. Age at CMR and TOF repair was 15 years [interquartile range (IQR) 9, 22] and 3.2 months (IQR 0.8, 6.2), respectively. Twelve (20%) had prior pulmonary valve replacement (PVR). MMP1 values were higher among those with prior PVR (16.7 (IQR 7.9, 25.5) vs 14.4 (IQR 9.9, 24.9), p = 0.02). When stratifying MMP1 into low and high groups, higher MMP1 was associated with higher indexed right (RV) and left ventricular (LV) mass and RV mass:volume ratios after adjusting for PVR. No other associations between biomarkers and CMR parameters were identified.

CONCLUSIONS

Only MMP1 was associated with markers of RV remodeling after TOF repair. As an enzyme involved in extracellular matrix degradation, MMP1 could be associated with fibrotic processes underlying RV remodeling, including dilation and hypertrophy. The additional biomarkers may not be specific towards cardiac remodeling. These findings merit further correlations with myocardial fibrosis measurements by CMR.

The Interplay between Myocardial Fibrosis, Strain Imaging and Collagen Biomarkers in Adults with Repaired Tetralogy of Fallot

Background: We sought to assess the interplay between right ventricle (RV) fibrosis, biventricular dysfunction based on global longitudinal strain (GLS) analysis, and biomarkers such as Galectin-3 (Gal-3), procollagen type III (PCIII), and NTproBNP. Methods: We studied 35 adult patients with rToF. All patients underwent a cardiac magnetic resonance (CMR) scan including feature tracking for deformation imaging. Blood biomarkers were measured. Results: LGE RV was detected in all patients, mainly at surgical sites. Patients with the highest RV LGE scoring had greater RV dilatation and dysfunction whereas left ventricular (LV) function was preserved. LV GLS correlated with RV total fibrosis score (p = 0.007). A LV GLS value of −15.9% predicted LGE RV score > 8 (AUC 0.754 (p = 0.02)). Neither RV GLS nor biomarker levels were correlated with the extent of RV fibrosis. A cut-off value for NTproBNP of 145.25 pg/mL predicted LGE RV score > 8 points (AUC 0.729, (p = 0.03)). A cut-off value for Gal-3 of 7.42 ng/mL predicted PR Fraction > 20% [AUC 0.704, (p = 0.05)]. Conclusions: A significant extent of RV fibrosis was mainly detected at surgical sites of RV, affecting RV performance. CMR-FT reveals subtle LV dysfunction in rToF patients, due to decreased performance of the fibrotic RV. Impaired LV function and elevated NTproBNP in rToF reflect a dysfunctional fibrotic RV.

Prognostic markers in patients undergoing transcatheter implantation of Venus P-valve: Experience in Taiwan

BACKGROUND/PURPOSE

Prognostic factors remain unclear in patients undergoing transcatheter implantation of Venus P-valve for their severe pulmonary regurgitation associated with native right ventricular (RV) outflow tract.

METHOD

Between January 2017 and October 2018, we prospectively collected data of patient characteristics, cardiac magnetic resonance imaging, cardiopulmonary exercise testing, and levels of N-terminal pro-B-type natriuretic peptide (NT-proBNP) before and 6-12 months after valve graft implantation.

RESULTS

Fifteen patients (male: 8, median age: 24.8 years) were enrolled. The procedure success rate was 100%. The median follow-up was 16.3 months without any dysfunction of the valve graft. The cohort demonstrated a significant improvement in cardiac index (from 3.3 to 3.9 L/min/m²) and increase of percentage of New York Heart Association functional class I (P < 10^-3), reduction in RV end-diastolic volume index (P = 0.008), and reductions in NT-proBNP levels (from 78.9 to 45.8 pg/mL, P = 0.040). However, the peak oxygen consumption (VO₂) dropped from 50.2% to 48.5% of the predicted value. Interestingly, we determined that patients with NT-proBNP levels below 70 pg/mL and left ventricular end-diastolic pressure (LVEDP) below 11 mmHg had a significantly higher chance of exhibiting improvement in peak VO₂ compared with those without (3/4 vs 1/10, P = 0.041).

CONCLUSION

In the small cohort with severe pulmonary regurgitation, implantation of a Venus P-valve led to promising reductions in RV volume. However, no definite improvement in cardiopulmonary exercise capacity or RV ejection fraction was achieved. Levels of NT-proBNP and LVEDP may be helpful for refining the indications of the Venus P-valve implantation.

Normalization of N-Terminal Pro-B-Type Natriuretic Peptide After Cardiac Surgery Among Children With Tetralogy of Fallot

The aim of this study was to temporally measure N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels over a period of 18 months after corrective surgery among children with tetralogy of Fallot (TOF) and to explore how commonly used pharmaceuticals (i.e., spironolactone and digoxin) might affect the normalization pattern. This retrospective study included 136 children with a median age of 7 months who underwent cardiac surgery for TOF. NT-proBNP level was measured at 1, 3, 6, 12, and 18 months after the surgery. Normalization of NT-proBNP was defined as an NT-proBNP level ≤250 pg/ml. The commonly used pharmaceuticals spironolactone and digoxin after discharge were collected. The normalization pattern, normalization time, and potential influence of the pharmaceuticals were determined. The rate of normalization was 24.2% (95% confidence interval [CI] 8.58% to 68.4%) per 100 person-days. Kaplan-Meier survival analysis showed a median normalization time of 517 (95% CI 429.6 to 604.3) days. The children whose NT-proBNP level did not normalize had a significantly higher readmission rate than those whose NT-proBNP level normalized (19.0% vs 2.8%, p = 0.018). Multivariable logistic regression models confirmed that the regular users of spironolactone, alone (odds ratio = 1.45, 95% CI 1.15 to 1.83) or in combination with digoxin (odds ratio = 1.28, 95% CI 1.03 to 1.58), had markedly faster recovery trajectories for measures of NT-proBNP than the irregular users of both. In conclusion, NT-proBNP normalization after cardiac surgery for TOF is a lengthy process, and irregular use of spironolactone could lead to failure in recovery and hospital readmission.

Cardiac biomarkers in children with congenital heart disease

BACKGROUND

Most congenital heart diseases (CHDs) have specific hemodynamics, including volume and pressure overload, as well as cyanosis and pulmonary hypertension, associated with anatomical abnormalities. Such hemodynamic abnormalities can cause activation of neurohormones, inflammatory cytokines, fibroblasts, and vascular endothelial cells, which in turn contribute to the development of pathologic conditions such as cardiac hypertrophy, fibrosis, and cardiac cell damages and death. Measuring biomarker levels facilitates the prediction of these pathological changes, and provides information about the stress placed on the myocardial cells, the severity of the damage, the responses of neurohumoral factors, and the remodeling of the ventricle. Compared to the ample information on cardiac biomarkers in adult heart diseases, data from children with CHD are still limited.

DATA SOURCES

We reviewed cardiac biomarkers-specifically focusing on troponin as a biomarker of myocardial damage, amino-terminal procollagen type III peptide (PIIIP) as a biomarker of myocardial fibrosis and stromal remodeling, and B-type natriuretic peptide (BNP)/N-terminal proBNP as biomarkers of cardiac load and heart failure, by introducing relevant publications, including our own, on pediatric CHD patients as well as adults.

RESULTS

Levels of highly sensitive troponin I are elevated in patients with atrial septal defects (ASDs) and ventricular septal defects (VSDs). PIIIP levels are also elevated in patients with ASD, VSD, pulmonary stenosis, and Tetralogy of Fallot. Measurement of BNP and N-terminal proBNP levels shows good correlation with heart failure score in children.

CONCLUSIONS

In the treatment of children with CHD requiring delicate care, it is vital to know the specific degree of myocardial damage and severity of heart failure. Cardiac biomarkers are useful tools for ascertaining the condition of CHDs with ease and are likely to be useful in determining the appropriate care of pediatric cardiology patients.

BNP in children with congenital cardiac disease: is there now sufficient evidence for its routine use?

Interest in brain natriuretic peptide (BNP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) in the management of children with CHD has increased. There are, however, no current guidelines for their routine use. The aim of this review article is to provide an update on the data regarding the use of BNP/NT-proBNP in the evaluation and surgical treatment of children with CHD. BNP/NT-proBNP levels in children with CHD vary substantially according to age, laboratory assay methods, and the specific haemodynamics associated with the individual congenital heart lesion. The accuracy of BNP/NT-proBNP as supplemental markers in the integrated screening, diagnosis, management, and follow-up of CHD has been established. In particular, the use of BNP/NT-proBNP as a prognostic indicator in paediatric cardiac surgery has been widely demonstrated, as well as its role in the subsequent follow-up of surgical patients. Most of the data, however, are derived from single-centre retrospective studies using multivariable analysis; prospective, randomised clinical trials designed to evaluate the clinical utility and cost-effectiveness of routine BNP/NT-proBNP use in CHD are lacking. The results of well-designed, prospective clinical trials should assist in formulating guidelines and expert consensus recommendations for its use in patients with CHD. Finally, the use of new point-of-care testing methods that use less invasive sampling techniques - capillary blood specimens - may contribute to a more widespread use of the BNP assay, especially in neonates and infants, as well as contribute to the development of screening programmes for CHD using this biomarker.