Evaluation of Ventricular Filling Pressures and Ventricular Function by Doppler Echocardiography in Patients with Functional Single Ventricle: Correlation with Simultaneous Cardiac Catheterization

Diastolic myocardial mechanics and their relation to ventricular filling pressures and postoperative course in functionally single ventricles

Diastolic dysfunction affects clinical outcomes in patients with a functionally single ventricle (FSV). The objective of this work is to study the association of ventricular mechanics and interventricular dependence on diastolic parameters and early post-Fontan outcomes. Sixty-one patients with FSV underwent echocardiography, cardiac catheterization, and magnetic resonance imaging on the same day before or after the Fontan procedure. Echocardiographic diastolic parameters, ventricular mass, and incoordinate wall motion, defined by the number of dyskinetic segments or by the lateral wall delay, were determined and studied for relationships with invasively measured hemodynamics and early postoperative Fontan course. In subjects with a sizable secondary ventricle, incoordinate motion was additionally analyzed at the left- and right-sided ventricular free walls. Resting ventricular end-diastolic pressure (VEDP) was ≤10 mmHg in most subjects. Individual echocardiographic parameters of the diastolic flow and tissue velocities did not correlate with VEDP, other hemodynamics, or post-Fontan clinical course. Incoordinate wall motion in the dominant and in the sizeable secondary ventricle, defined by the lateral wall delay or by the number of dyskinetic segments, was the only echo parameter that correlated, albeit weakly, with VEDP (r = 0.247, P = 0.040), oxygen saturation (r = -0.417, P = 0.001), pulmonary vascular resistance and flow (Qp) (r = -0.303, P = 0.011), Fontan fenestration flow (r = 0.512, P = 0.009), and duration of endotracheal intubation (r = 0.292, P = 0.022). When the nondominant (secondary) ventricle was accounted for in the analysis of incoordinate wall motion, these associations strengthened. The degree of incoordinate ventricular wall motion in diastole was associated with VEDP and postoperative Fontan course in FSV. Analysis of incoordinate wall motion of the dominant and sizeable secondary ventricle may be warranted and should be included in the assessment of the FSV after the Fontan procedure.NEW & NOTEWORTHY Diastolic dysfunction affects outcomes in patients with functionally single ventricles (FSVs) but is difficult to assess. We found that incoordinate wall motion was the only echo parameter that correlated with FSV end-diastolic pressure, oxygen saturation, pulmonary vascular resistance and flow, and duration of endotracheal intubation. Analysis of incoordinate wall motion in the nondominant (secondary) ventricle strengthened these associations. Analyzing incoordinate wall motion should be included in the assessment of the FSV after the Fontan procedure.

Single ventricular strain measures correlate with peak oxygen consumption in children and adolescents with Fontan circulation

INTRODUCTION

Children with a single ventricle post-Fontan palliation are at increased risk of poor outcomes with peak oxygen consumption acting as a surrogate outcome marker. The purpose of this study is to evaluate the relationship between peak oxygen consumption and echocardiographic measures of ventricular function and deformation, including ventricular global longitudinal strain and dyssynchrony, in children and adolescents following Fontan palliation.

METHODS

Patients (age 8-21 years) with single ventricle post-Fontan palliation were prospectively recruited and participated in an echocardiogram, including views optimised for two-dimensional speckle tracking, and a cardiopulmonary exercise test on a cycle ergometer to maximal volitional fatigue.

RESULTS

Thirty-eight patients (mean age 13.7 ± 2.3 years) post-Fontan palliation had either a single left ventricular (n = 20), single right ventricular (n = 14), or biventricular (n = 4) morphology. Peak oxygen consumption (24.9 ± 5.6 ml/kg/minute) was correlated with global longitudinal strain (r = -0.435, p = 0.007), a strain discoordination time to peak index (r = -0.48, p = 0.003), and the presence of an electro-mechanical dyssynchrony strain pattern (p = 0.008). On multivariate regression modelling, these three variables were associated with peak oxygen consumption independently of age and sex. The single right ventricular group had evidence of possible diastolic dysfunction by E/e' compared to the single left ventricular and biventricular groups (p = 0.001).

CONCLUSIONS

Strain analysis measures are correlated with peak oxygen consumption in this cohort of children, adolescents, and young adults following Fontan palliation, suggesting that ventricular mechanics may influence the efficiency of the Fontan circulation.

Heart Failure with Preserved Ejection Fraction in Children

Diastolic dysfunction (DD) refers to abnormalities in the mechanical function of the left ventricle (LV) during diastole. Severe LVDD can cause symptoms and the signs of heart failure (HF) in the setting of normal or near normal LV systolic function and is referred to as diastolic HF or HF with preserved ejection fraction (HFpEF). Pediatric cardiologists have long speculated HFpEF in children with congenital heart disease and cardiomyopathy. However, understanding the risk factors, clinical course, and validated biomarkers predictive of the outcome of HFpEF in children is challenging due to heterogeneous etiologies and overlapping pathophysiological mechanisms. The natural history of HFpEF varies depending upon the patient's age, sex, race, geographic location, nutritional status, biochemical risk factors, underlying heart disease, and genetic-environmental interaction, among other factors. Pediatric onset HFpEF is often not the same disease as in adults. Advances in the noninvasive evaluation of the LV diastolic function by strain, and strain rate analysis with speckle-tracking echocardiography, tissue Doppler imaging, and cardiac magnetic resonance imaging have increased our understanding of the HFpEF in children. This review addresses HFpEF in children and identifies knowledge gaps in the underlying etiologies, pathogenesis, diagnosis, and management, especially compared to adults with HFpEF.

Impact of Udenafil on Echocardiographic Indices of Single Ventricle Size and Function in FUEL Study Participants

BACKGROUND

The FUEL trial (Fontan Udenafil Exercise Longitudinal) demonstrated statistical improvements in exercise capacity following 6 months of treatment with udenafil (87.5 mg po BID). The effect of udenafil on echocardiographic measures of single ventricle function in this cohort has not been studied.

METHODS

The 400 enrolled participants were randomized 1:1 to udenafil or placebo. Protocol echocardiograms were obtained at baseline and 26 weeks after initiation of udenafil/placebo. Linear regression compared change from baseline indices of single ventricle systolic, diastolic and global function, atrioventricular valve regurgitation, and mean Fontan fenestration gradient in the udenafil cohort versus placebo, controlling for ventricular morphology (left ventricle versus right ventricle/other) and baseline value.

RESULTS

The udenafil participants (n=191) had significantly improved between baseline and 26 weeks visits compared to placebo participants (n=195) in myocardial performance index (P=0.03, adjusted mean difference [SE] of changes between groups -0.03[0.01]), atrioventricular valve inflow peak E (P=0.009, 3.95 [1.50]), and A velocities (P=0.034, 3.46 [1.62]), and annular Doppler tissue imaging-derived peak e' velocity (P=0.008, 0.60[0.23]). There were no significant differences in change in single ventricle size, systolic function, atrioventricular valve regurgitation severity, or mean fenestration gradient. Participants with a dominant left ventricle had significantly more favorable baseline values of indices of single ventricle size and function (lower volumes and areas, E/e' ratio, systolic:diastolic time and atrioventricular valve regurgitation, and higher annular s' and e' velocity).

CONCLUSIONS

FUEL participants who received udenafil demonstrated a statistically significant improvement in some global and diastolic echo indices. Although small, the changes in diastolic function suggest improvement in pulmonary venous return and/or augmented ventricular compliance, which may help explain improved exercise performance in that cohort.

REGISTRATION

URL: https://clinicaltrials.gov; Unique Identifier: NCT02741115.

Understanding Complex Interactions in Pediatric Diastolic Function Assessment

BACKGROUND

Diagnosing left ventricular diastolic dysfunction (DD) non-invasively in children is difficult as no validated pediatric diagnostic algorithm is available. The aim of this study is to explore the use of machine learning (ML) to develop a model that uses echocardiographic measurements that explains patterns in invasively measured markers of DD in children.

METHODS

We enrolled children at-risk for developing DD including patients with Kawasaki disease, heart transplant, aortic stenosis, and coarctation of the aorta when undergoing clinical left heart catheterization. We obtained simultaneous invasive pressure measurements with high-fidelity catheter (time constant of isovolumic relaxation [Tau], LV end diastolic pressure [LVEDP], -dP/dt max) and echocardiographic DD measurements. Spearman correlations were performed for each echo feature with invasive markers to understand pairwise relationships. Separate random forest (RF) models were implemented to assess all echocardiographic features, key demographic data, and clinical diagnosis in predicting invasive markers. A backward stepwise regression model was simultaneously implemented as a comparative conventional reference model. The relative importance of all parameters was ranked in terms of accuracy reduction. Model approximation was then performed using a regression tree with the top ranked features of each RF model to improve model interpretability. Regression coefficients of the linear models were presented.

RESULTS

Fifty-nine children were included. Spearman correlations were generally low. The RF models' performance measures were non-inferior to the linear model. However, the linear model's regression coefficients were unintuitive. The highest-ranked important features for the RF models were propagation velocity (Vp) for Tau; E/Vp ratio for LVEDP; and systolic global longitudinal strain rate for -dP/dt max.

CONCLUSIONS

Estimating individual components of DD can potentially improve the noninvasive assessment of pediatric DD. Although pairwise correlations measured were weak and linear regression coefficients unintuitive, approximated ML models aided in understanding how echocardiographic and invasive parameters of DD are related. This ML approach could help in further development of pediatric-specific diagnostic algorithms.

Management of circulatory failure after Fontan surgery

With improvement in survival after Fontan surgery resulting in an increasing number of older survivors, there are more patients with a Fontan circulation experiencing circulatory failure each year. Fontan circulatory failure may have a number of underlying etiologies. Once Fontan failure manifests, prognosis is poor, with patient freedom from death or transplant at 10 years of only about 40%. Medical treatments used include traditional heart failure medications such as renin-angiotensin-aldosterone system blockers and beta-blockers, diuretics for symptomatic management, antiarrhythmics for rhythm control, and phosphodiesterase-5 inhibitors to decrease PVR and improve preload. These oral medical therapies are typically not very effective and have little data demonstrating benefit; if there are no surgical or catheter-based interventions to improve the Fontan circulation, patients with severe symptoms often require inotropic medications or mechanical circulatory support. Mechanical circulatory support benefits patients with ventricular dysfunction but may not be as useful in patients with other forms of Fontan failure. Transplant remains the definitive treatment for circulatory failure after Fontan, but patients with a Fontan circulation face many challenges both before and after transplant. There remains significant room and urgent need for improvement in the management and outcomes of patients with circulatory failure after Fontan surgery.

Myocardial Perfusion in Hypoplastic Left Heart Syndrome

BACKGROUND

The status of the systemic right ventricular coronary microcirculation in hypoplastic left heart syndrome (HLHS) is largely unknown. It is presumed that the systemic right ventricle's coronary microcirculation exhibits unique pathophysiological characteristics of HLHS in Fontan circulation. The present study sought to quantify myocardial blood flow by cardiac magnetic resonance imaging and evaluate the determinants of microvascular coronary dysfunction and myocardial ischemia in HLHS.

METHODS

One hundred nineteen HLHS patients (median age, 4.80 years) and 34 healthy volunteers (median age, 5.50 years) underwent follow-up cardiac magnetic resonance imaging ≈1.8 years after total cavopulmonary connection. Right ventricle volumes and function, myocardial perfusion, diffuse fibrosis, and late gadolinium enhancement were assessed in 4 anatomic HLHS subtypes. Myocardial blood flow (MBF) was quantified at rest and during adenosine-induced hyperemia. Coronary conductance was estimated from MBF at rest and catheter-based measurements of mean aortic pressure (n=99).

RESULTS

Hyperemic MBF in the systemic ventricle was lower in HLHS compared with controls (1.89±0.57 versus 2.70±0.84 mL/g per min; P<0.001), while MBF at rest normalized by the rate-pressure product, was similar (1.25±0.36 versus 1.19±0.33; P=0.446). Independent risk factors for a reduced hyperemic MBF were an HLHS subtype with mitral stenosis and aortic atresia (P=0.017), late gadolinium enhancement (P=0.042), right ventricular diastolic dysfunction (P=0.005), and increasing age at total cavopulmonary connection (P=0.022). The coronary conductance correlated negatively with systemic blood oxygen saturation (r, -0.29; P=0.02). The frequency of late gadolinium enhancement increased with age at total cavopulmonary connection (P=0.014).

CONCLUSIONS

The coronary microcirculation of the systemic ventricle in young HLHS patients shows significant differences compared with controls. These hypothesis-generating findings on HLHS-specific risk factors for microvascular dysfunction suggest a potential benefit from early relief of frank cyanosis by total cavopulmonary connection.

Identification of patient variables that are associated with ventricular end-diastolic pressure before the bidirectional Glenn operation

INTRODUCTION

Systemic ventricular end-diastolic pressure is important in patients with single ventricle heart disease. Predictors of an elevated systemic ventricular end-diastolic pressure prior to bidirectional Glenn operation have been incompletely identified.

METHODS

All patients who underwent bidirectional Glenn operation operation at our centre between January 2007 and March 2017 were retrospectively identified and patient variables were extracted. For patients who had undergone Fontan operation at the time of this study, post-Fontan patient variables were also extracted.

RESULTS

One-hundred patients were included with a median age at pre-bidirectional Glenn operation catheterisation of 4.5 months. In total, 71 (71%) patients had a systemic right ventricle. At the pre-bidirectional Glenn operation catheterisation, the mean systemic ventricular end-diastolic pressure was higher amongst those with systemic right ventricle compared to left ventricle (9.1 mmHg ± 2.1 versus 7.7 ± 2.7 mmHg, p < 0.01). On univariate analysis, pre-bidirectional Glenn operation systemic ventricular end-diastolic pressure was positively associated with the presence of a systemic right ventricle (p < 0.01), history of recoarctation (p = 0.03), history of Norwood operation (p = 0.04), and ventricular systolic pressure (p < 0.01). On multivariate analysis, systemic ventricular end-diastolic pressure was positively associated with the presence of a systemic right ventricle (p < 0.01) and ventricular systolic pressure (p < 0.01). Amongst those who had undergone Fontan operation at the time of study (n = 49), those with a higher pre-bidirectional Glenn operation systemic ventricular end-diastolic pressure were more likely to have experienced death, transplantation, or listed for transplantation (p = 0.02) and more likely to have had heart failure symptoms (p = 0.04) at a mean time from Fontan of 5.2 years ± 1.3.

CONCLUSIONS

In patients undergoing bidirectional Glenn operation operation, the volume-loaded, pre-bidirectional Glenn operation state may expose diastolic dysfunction that has prognostic value.

Heart failure with reduced and preserved ejection fraction in adult congenital heart disease

Heart failure with reduced ejection fraction (HFrEF) is common in patients with adult congenital heart disease. Many of the most common congenital defects have a high prevalence of HFrEF, including left-sided obstructive lesions (aortic stenosis, coarctation of the aorta, Shone complex), tetralogy of Fallot, Ebstein anomaly, lesions in which there is a systemic right ventricle, and lesions palliated with a Fontan circulation. However, heart failure with preserved ejection fraction (HFpEF) is also prevalent in all these lesions. Comprehensive evaluation includes physical exam, biomarkers, echocardiography and advanced imaging, exercise stress testing, and, in some cases, invasive hemodynamics. Guideline-directed medical therapy for HFrEF can be applied to left-sided lesions and may be considered on an individual basis for systemic right ventricle and single-ventricle patients. Medical therapy is limited for HFpEF. However, in both HFrEF and HFpEF, ventricular dyssynchrony and arrhythmias play an important role, and medications for rhythm control, ablation, and cardiac resynchronization therapy should be considered. Finally, aggressive management of cardiovascular risk factors and comorbidities, including, but not limited to, hypertension, obesity, diabetes, dyslipidemia, and obstructive sleep apnea, cannot be overemphasized.

Single ventricle systolic function and cardiopulmonary exercise performance in adult patients with Fontan circulation

OBJECTIVE

We employed echocardiographic tissue characterization for the assessment of single ventricle systolic function and examined its relationship with cardiopulmonary exercise testing (CPET) performance in the Fontan circulation.

METHODS

40 consecutive adult Fontan patients (16 female, 24 male; mean age 26.3 ± 5.9) were enrolled in our prospective cross-sectional study. All patients underwent echocardiographic assessment including tissue characterization and CPET within 3 days from each other.

RESULTS

LAPSE (lateral annular plane systolic excursion) was higher in patients with a dominant left ventricle compared to a dominant right ventricle (12.3 + -2.6 vs 9.8 + -1.1 mm, p = .008) and in patients with AP (right atrium-pulmonary artery) connection than with lateral tunnel or extracardiac conduits (13.9 ± 1.7 vs 11.3 ± 2.6 and 10.9 ± 2.2 mm, p = .014 and p = .014, respectively). Maximal oxygen pulse (O₂ pulse max) was significantly higher in patients with a dominant left or common ventricle compared to patients with a dominant right ventricle (10.3 and 12.0 vs 6.6 ml/beat, p = .002 and p = .032, respectively). There was a positive correlation between O₂ pulse max and LAPSE (r = 0.442, p = .009), atrioventricular valve annulus systolic velocity (S') (r = 0.606, p < .0001), lateral wall basal segment systolic velocity (bas vel s) (r = 0.469, p = .009) and lateral wall mid segment systolic velocity (mid vel s) (r = 0.452, p = .012). In the multivariable regression model, S' (r = 0.606, p < .0001) remained predictive of O₂ pulse max.

CONCLUSIONS

LAPSE and S' are suitable parameters for the assessment of systolic function in Fontan patients. Subclinical systolic dysfunction of longitudinal fibers is associated with worse CPET performance. O₂ pulse max seems to be the best parameter reflecting Fontan patients' physical performance.

Comparison of echocardiographic measurements to invasive measurements of diastolic function in infants with single ventricle physiology: a report from the Pediatric Heart Network Infant Single Ventricle Trial

BACKGROUND

While echocardiographic parameters are used to quantify ventricular function in infants with single ventricle physiology, there are few data comparing these to invasive measurements. This study correlates echocardiographic measures of diastolic function with ventricular end-diastolic pressure in infants with single ventricle physiology prior to superior cavopulmonary anastomosis.

METHODS

Data from 173 patients enrolled in the Pediatric Heart Network Infant Single Ventricle enalapril trial were analysed. Those with mixed ventricular types (n = 17) and one outlier (end-diastolic pressure = 32 mmHg) were excluded from the analysis, leaving a total sample size of 155 patients. Echocardiographic measurements were correlated to end-diastolic pressure using Spearman's test.

RESULTS

Median age at echocardiogram was 4.6 (range 2.5-7.4) months. Median ventricular end-diastolic pressure was 7 (range 3-19) mmHg. Median time difference between the echocardiogram and catheterisation was 0 days (range -35 to 59 days). Examining the entire cohort of 155 patients, no echocardiographic diastolic function variable correlated with ventricular end-diastolic pressure. When the analysis was limited to the 86 patients who had similar sedation for both studies, the systolic:diastolic duration ratio had a significant but weak negative correlation with end-diastolic pressure (r = -0.3, p = 0.004). The remaining echocardiographic variables did not correlate with ventricular end-diastolic pressure.

CONCLUSION

In this cohort of infants with single ventricle physiology prior to superior cavopulmonary anastomosis, most conventional echocardiographic measures of diastolic function did not correlate with ventricular end-diastolic pressure at cardiac catheterisation. These limitations should be factored into the interpretation of quantitative echo data in this patient population.

Velocity vector imaging for the assessment of segmental ventricular function in children with a single right ventricle after cavopulmonary anastomosis

OBJECTIVE

Ventricular function assessment is very important for the treatment and prognostic classification of children with a single right ventricle (SRV) after cavopulmonary anastomosis (CPA). However, unusual ventricular shapes can result in inaccurate measurements. The aim of this study was to evaluate velocity vector imaging (VVI) for assessing segmental ventricular function in children with SRV after CPA.

METHODS

Twenty-one children with SRV after CPA and 21 age- and sex-matched children with normal biventricular anatomy and function were included. The longitudinal velocity, displacement, strain and strain rate were measured in the two groups in six segments by VVI. The velocity, displacement, strain and strain rate of the SRVs were compared with max(dp/dt) measured during simultaneous cardiac catheterization in the SRV subjects.

RESULTS

The control group consisted of 13 males and 8 females (69% males) with a mean age of 6.7 ± 3.5 years and mean weight of 20.5 ± 6.5 kg, and the study group consisted of 13 males and 8 females with a mean age 6.7 ± 3.7 years and mean weight of 20.6 ± 6.8 kg. Age, weight and sex distribution were similar between the groups (all, p > .05). Strain and strain rate values in all six segments were significantly lower in the study group than in the control group (all, p < .05). The max(dp/dt) of the SRV was 522.84 ± 158.32 mmHg/s, and the strain rate of the basal segment at the rudimentary chamber correlated best with max(dp/dt) (r = 0.74, p < .01).

CONCLUSIONS

Segmental ventricular dysfunction was present in children with SRV after CPA, and it could be assessed using VVI.

Systolic/diastolic ratio correlates with end diastolic pressures in pediatric patients with single right ventricles

BACKGROUND

Increased ventricular end-diastolic pressure (VEDP) is a known risk factor for morbidity and mortality in patients with single right ventricle (RV) physiology. Previous studies have shown mixed results correlating echocardiographic measurements with catheter-derived VEDP in this population. Goal of this study was to evaluate if echocardiographic systolic/diastolic ratio (S/D) correlated with VEDP.

METHODS

Patients with single RV physiology who underwent simultaneous echocardiography and catheterization were evaluated. Systolic and diastolic durations were measured using tricuspid inflow durations from Doppler analysis to calculate the S/D ratio. VEDP was obtained from the catheterization report.

RESULTS

Twenty-seven studies were performed on patients with single RV physiology. Median age at time of catheterization was 11.4 months (range, 0-132 months). Mean VEDP was 9.9 ± 4.5 mm Hg. S/D ratio was 1.8 ± 0.5. S/D ratio significantly correlated with VEDP (r = 0.63, P < .01). Optimum value of S/D ratio for discriminating between patients with high (>10 mm Hg) vs low EDP was found to be 1.9. High S/D ratio had an area under the curve of 0.82 (0.65, 1.0), with 75% sensitivity and 89% specificity for predicting elevated VEDP.

CONCLUSION

In patients with single RV physiology, S/D significantly correlated with VEDP. S/D ratio is a simple technique that may be useful in both estimating and discriminating between high and low VEDP in this complex patient population.

R-Wave Modified Tissue Doppler Imaging Myocardial Performance Index for the Assessment of Cardiac Function in Children with Congestive Heart Failure: A Feasibility Study

Background

The aim of this study was to evaluate the feasibility of an R-wave modified tissue Doppler imaging (TDI) myocardial performance index (MPI), or MPI TDI-R, for the assessment of cardiac function in children with congestive heart failure (CHF).

Material/Methods

Forty children with CHF and 40 normal children were evaluated using the modified pediatric Ross heart failure grading system. TDI recorded the spectrum of diastolic function at the mitral valve annulus to measure the MPI. Twelve-lead electrocardiogram (ECG) measured the R-wave in the QRS complex, resulting in the modified MPI TDI-R. Correlation between the MPI TDI-R, other echocardiographic indices, and the Ross heart failure grades were analyzed, with reproducibility analysis.

Results

Compared with normal children, the MPI TDI and MPI TDI-R were significantly increased in the pediatric CHF group (P<0.01). The MPI TDI-R was significantly correlated with other indices of cardiac function and Ross grading for CHF in children (r=0.769). The MPI TDI-R showed good correlation with the findings of the MPI TDI, calculated by traditional methods. Receiver-operating characteristic (ROC) curve analysis showed that the MPI TDI-R had a sensitivity of 67.5%, and a specificity of 97.5%. The reproducibility of the MPI TDI-R was confirmed to be superior when compared with the non-modified MPI TDI.

Conclusions

This feasibility study showed that the modified MPI TDI-R, formed by combining the MPI TDI with synchronous surface ECG measurements, was simple to perform, reproducible, and provided a specific index for the assessment of cardiac function in children with CHF.

Consensus recommendations for echocardiography in adults with congenital heart defects from the International Society of Adult Congenital Heart Disease (ISACHD)

The population of adults with congenital heart disease (ACHD) is increasing constantly due to medical, surgical and interventional successes and the input from advanced cardiovascular imaging. ACHD patients are at continuing risk of residua and sequelae related to their CHD contributing to significant morbidity and mortality. Consequently, lifelong expert surveillance is recommended for most patients. Healthcare providers are still working out how best to achieve this objective, how to train enough experts to provide high quality care, and how to organize the delivery of care. Echocardiography is crucial to clinical surveillance providing a comprehensive assessment of cardiac morphology, physiology, pathophysiology, and function. Thus it contributes significantly to the overall clinical management of ACHD patients. The International Society for Adult Congenital Heart Disease (ISACHD; www.isachd.org) is the leading organization of professionals worldwide dedicated to the pursuit of excellence in the care of ACHD patients. Recognizing the critical role of imaging in the diagnosis and management of ACHD, ISACHD established a task force to provide guidance on echocardiographic studies and reporting. The rationale is that standardization of echocardiographic imaging and reporting carries the potential to improve the overall quality of these exams around the world and facilitate collaborative multicenter research. The standardized ACHD protocols provided by the ISACHD task force (found in the appendices) include specific recommendations for data acquisition and reporting for each of the major adult congenital heart lesions. These protocols give a comprehensive and structured approach in the evaluation of ACHD patients and help to ensure excellent patient care.

Risk Factors for an Elevated Ventricular End-Diastolic Pressure Prior to the Fontan Operation

Systemic ventricular end-diastolic pressure (SVEDP) is an important determinant of pulmonary artery pressure in those with a Fontan circulation. Predictors of an elevated SVEDP have been incompletely identified in this population. All who underwent the Fontan operation at our center between 1/2009 and 12/2013 were retrospectively identified. SVEDP at the pre-Fontan catheterization and other patient variables were extracted. We identified 61 patients. Pre-Fontan SVEDP was positively associated with systemic ventricular systolic pressure (β = 0.4, p = 0.004), aortic systolic pressure (β = 0.3, p = 0.007), aortic mean pressure (β = 0.3, p = 0.02), and decreased ventricular systolic function (p = 0.03). Compared to those with pre-Fontan SVEDP ≤ 7 mmHg, patients with SVEDP > 7 mmHg had higher average ventricular systolic pressure (85.0 ± 7.5 vs. 78.7 ± 8.3 mmHg, p = 0.003), higher average descending aorta mean pressure (62.4 ± 4.9 vs. 58.6 ± 8.1 mmHg, p = 0.03), and a higher incidence of decreased ventricular systolic function (36 vs. 15%, p = 0.07). For those with a systemic right ventricle, the SVEDP decreased significantly from the pre-Stage 2 to pre-Fontan measurements (8.7 ± 2.6 vs. 7.3 ± 2.0 mmHg, p = 0.02), but not for those with a systemic left ventricle (7.8 ± 2.0 vs. 7.2 ± 1.8 mmHg, p = 0.3). At pre-Fontan catheterization, decreased ventricular systolic function and markers of systemic afterload were positively associated with the SVEDP. SVEDP decreased significantly after Stage 2 for those with a systemic right ventricle, but not for those with a systemic left ventricle; the systemic right ventricle may be particularly vulnerable to pre-Stage 2 volume loading.

Echocardiographic right ventricular function correlations with cardiac catheterisation data in biventricular congenital heart patients

BACKGROUND

Newer echocardiographic techniques may allow for more accurate assessment of right ventricular function. Adult studies have correlated these echocardiographic measurements with invasive data, but minimal data exist in the paediatric congenital heart population. The purpose of this study was to evaluate echocardiographic measurements that correlate best with right ventricular systolic and diastolic catheterisation parameters.

METHODS

Patients with two-ventricle physiology who underwent simultaneous echocardiogram and cardiac catheterisation were included in this study. Right ventricular systolic echocardiographic data included fractional area change, displacement, tissue Doppler imaging s' wave, global longitudinal strain, and strain rate s' wave. Diastolic echocardiographic data included tricuspid E and A waves, tissue Doppler imaging e' and a' waves, and strain rate e' and a' waves. E/tissue Doppler imaging e', tissue Doppler imaging e'/tissue Doppler imaging a', E/strain rate e', and strain rate e'/strain rate a' ratios were also calculated. Catheterisation dP/dt was used as a marker for systolic function and right ventricular end-diastolic pressure for diastolic function.

RESULTS

A total of 32 patients were included in this study. The median age at catheterisation was 3.1 years (0.3-17.6 years). The DP/dt was 493±327 mmHg/second, and the right ventricular end-diastolic pressure was 7.7±2.4 mmHg. There were no significant correlations between catheterisation dP/dt and systolic echocardiographic parameters. Right ventricular end-diastolic pressure correlated significantly with strain rate e' (r=-0.4, p=0.02), strain rate a' (r=-0.5, p=0.03), and E/tissue Doppler imaging e' (r=0.4, p=0.04).

CONCLUSION

Catheterisation dP/dt did not correlate with echocardiographic measurements of right ventricular systolic function. Strain rate and tissue Doppler imaging analysis significantly correlated with right ventricular end-diastolic pressure. These values should be further studied to determine whether they may be used as an alternative method to estimate right ventricular end-diastolic pressure in this patient population.

Pulmonary Vein Doppler Patterns in Infants with Single Right Ventricle Anomalies After Initial Staged Palliations

The aim of this study was to describe serial changes in echocardiographic Doppler pulmonary vein flow (PVF) patterns in infants with single right ventricle (RV) anomalies enrolled in the Single Ventricle Reconstruction trial. Measurement of PVF peak systolic (S) and diastolic (D) velocities, velocity time integrals (VTI), S/D peak velocity and VTI ratios, and frequency of atrial reversal (Ar) waves were made at three postoperative time points in 261 infants: early post-Norwood, pre-stage II surgery, and 14 months. Indices were compared over time, between initial shunt type [modified Blalock-Taussig shunt (MBTS) and right ventricle-to-pulmonary artery shunt (RVPAS)] and in relation to clinical outcomes. S velocities and VTI increased over time while D wave was stable, resulting in increasing S/D peak velocity and VTI ratios, with a median post-Norwood S/D VTI ratio of 1.14 versus 1.38 at pre-stage II and 1.89 at 14 months (P < 0.0001 between intervals). MBTS subjects had significantly higher S/D peak velocity and VTI ratios compared to RVPAS at the post-Norwood and pre-stage II time points (P < 0.0001) but not by 14 months. PVF patterns did not correlate with survival or hospitalization course at 1 year. PVF patterns after Norwood palliation differ from normal infants by having a dominant systolic pattern throughout infancy. PVF differences based upon shunt type resolve by 14 months and did not correlate with clinical outcomes. This study describes normative values and variations in PVF for infants with a single RV from shunt-dependent pulmonary blood flow to cavopulmonary blood flow.

A preliminary comparison of two-dimensional speckle tracking echocardiography and pressure-volume loop analysis in patients with Fontan physiology: The role of ventricular morphology

OBJECTIVE

Speckle tracking echocardiography (STE) may be a useful modality for assessing ventricular performance in patients with single ventricle physiology. However, STE's ability to accurately assess ventricular performance in this population is unknown. The objective of this study was to perform a preliminary comparison of STE measures of myocardial deformation to reference standard measures of function derived from pressure-volume loop (PVL) analysis.

DESIGN

This was a secondary analysis of a prospective study investigating PVLs in patients with Fontan physiology. PVLs were recorded using microconductance catheters. PVL indices included end-systolic elastance (Ees), arterial elastance (Ea), ventriculo-arterial coupling (Ea/Ees), and the isovolumic relaxation time constant (tau). Patients were included if they had an echocardiogram within 1 month of their catheterization. STE was performed retrospectively using vendor independent software.

RESULTS

Seventeen patients had echocardiograms available for analysis, 12 were right ventricular (RV) dominant. The median age was 8 years (IQR 5-17 years). Circumferential strain (r=-.72, P≤.01) and strain rate (r=-.61, P=.04) correlated with Ea/Ees in those with RV-dominant morphology. Longitudinal strain rate correlated with Ees in those with LV-dominant morphology (r=-.98, P≤.01). Longitudinal EDSR correlated with tau in those with LV-dominant morphology (r=-.90, P=.04).

CONCLUSIONS

In this limited sample, circumferential measures of deformation correlated with PVL measures better in patients with RV morphology, while longitudinal measures correlated better with PVL measures in patients with LV morphology. Further validation and investigation into the clinical usefulness of these measures are warranted.

Managing adult Fontan patients: where do we stand?

The Fontan operation is performed as a palliative procedure to improve survival in infants born with a functionally univentricular circulation. The success of the operation is demonstrated by a growing adult Fontan population that exists with this unique physiology. Late follow-up has demonstrated expected and unexpected sequelae, and has shown multisystem effects of this circulation. This review discusses the challenges of managing the late complications in terms of understanding this unique physiology and the innovative therapeutic interventions that are being investigated. The challenge remains to maintain quality of life for adult survivors, as well as extending life expectancy.

Innovative solutions are required to meet the challenges of the Fontan circulation faced in adult lifehttp://ow.ly/XTSm305oH8b

Assessment of Diastolic Function in Single-Ventricle Patients After the Fontan Procedure

BACKGROUND

Patients with functional single ventricles after the Fontan procedure have abnormal cardiac mechanics. The aims of this study were to determine factors that influence diastolic function and to describe associations of diastolic function with current clinical status.

METHODS

Echocardiograms were obtained as part of the Pediatric Heart Network Fontan Cross-Sectional Study. Diastolic function grade (DFG) was assessed as normal (grade 0), impaired relaxation (grade 1), pseudonymization (grade 2), or restrictive (grade 3). Studies were also classified dichotomously (restrictive pattern present or absent). Relationships between DFG and pre-Fontan variables (e.g., ventricular morphology, age at Fontan, history of volume-unloading surgery) and current status (e.g., systolic function, valvar regurgitation, exercise performance) were explored.

RESULTS

DFG was calculable in 326 of 546 subjects (60%) (mean age, 11.7 ± 3.3 years). Overall, 32% of patients had grade 0, 9% grade 1, 37% grade 2, and 22% grade 3 diastolic function. Although there was no association between ventricular morphology and DFG, there was an association between ventricular morphology and E', which was lowest in those with right ventricular morphology (P < .001); this association remained significant when using Z scores adjusted for age (P < .001). DFG was associated with achieving maximal effort on exercise testing (P = .004); the majority (64%) of those not achieving maximal effort had DFG 2 or 3. No additional significant associations of DFG with laboratory or clinical measures were identified.

CONCLUSIONS

Assessment of diastolic function by current algorithms results in a high percentage of patients with abnormal DFG, but few clinically or statistically significant associations were found. This may imply a lack of impact of abnormal diastolic function on clinical outcomes in this cohort, or it may indicate that the methodology may not be applicable to pediatric patients with functional single ventricles.

Evaluation of single right atrial volume and function with magnetic resonance imaging in children with hypoplastic left heart

BACKGROUND

Standardized methods to evaluate atrial properties in single ventricles are lacking.

OBJECTIVE

To determine the feasibility of quantifying right atrial volumes and function in hypoplastic left heart using MRI.

MATERIALS AND METHODS

We studied 15 infants with hypoplastic left heart prior to Glenn surgery (mean age 4.2 months [standard deviation 0.3]) who underwent cardiac MRI with evaluation of atrial volumes and emptying fraction using monoplane two-chamber, monoplane four-chamber, and biplane methods, all of which were compared to the atrial short-axial oblique stack method. We compared atrial end-diastolic volume, end-systolic volume and emptying fraction among these methods. We analyzed reproducibility of the methods using Bland‒Altman plots.

RESULTS

Both four-chamber and biplane methods showed high correlations for atrial end-diastolic volume (r = 0.7 and r = 0.8, respectively; P < 0.01) and end-systolic volume (r = 0.8 and r = 0.9, respectively; P < 0.01) with small mean differences (-0.2 ± 2.9 standard deviation [SD] ml and -0.8 ± 1.6 ml, respectively, for atrial end-diastolic volume and -0.8 ± 1.5 ml and -0.9 ± 0.9 ml, respectively, for atrial end-systolic volume). The short-axial oblique method was the most reproducible, followed by the four-chamber method.

CONCLUSION

MRI assessment of atrial volume and function is feasible in hypoplastic left heart and might provide further insight into single-ventricle mechanics.

Correlations Between Echocardiographic Systolic and Diastolic Function with Cardiac Catheterization in Biventricular Congenital Heart Patients

Newer echocardiographic techniques may allow for more accurate assessment of left ventricular (LV) function. Adult studies have correlated these echocardiographic measurements with invasive data, but minimal data exist in the pediatric congenital heart population. Purpose of this study was to evaluate which echocardiographic measurements correlated best with LV systolic and diastolic catheterization parameters. Patients with two-ventricle physiology who underwent simultaneous echocardiogram and cardiac catheterization were included. Images were obtained in the four-chamber view. LV systolic echocardiographic data included ejection fraction, displacement, tissue Doppler imaging (TDI) s' wave, global longitudinal strain, and strain rate (SR) s' wave. Diastolic echocardiographic data included mitral E and A waves, TDI e' and a' waves, and SRe' and SRa' waves. E/TDI e', TDI e'/TDI a', E/SRe', and SRe'/SRa' ratios were also calculated. Catheterization dP/dt was used as a marker for systolic function, and LV end-diastolic pressure (EDP) was used as a marker for diastolic function. Correlations of the echocardiographic and catheterization values were performed using Pearson correlation. Twenty-nine patients were included (14 females, 15 males). Median age at catheterization was 3.4 years (0.04-17.4 years). dP/dt was 1258 ± 353 mmHg/s, and LVEDP was 10.8 ± 2.4 mmHg. There were no significant correlations between catheterization dP/dt and systolic echocardiographic parameters. LVEDP correlated significantly with SRe' (r = -0.4, p = 0.03), SRa' (r = -0.4, p = 0.03), and E/SRe' (r = 0.5, p = 0.004). In pediatric congenital heart patients, catheterization dP/dt did not correlate with echocardiographic measurements of LV systolic function. Further studies are needed to determine which echocardiographic parameter best describes LV systolic function in this population. Strain rate analysis significantly correlated with LVEDP. Strain rate analysis should be considered as an alternative method to estimate LVEDP in this patient population.

Echocardiography in the Assessment of Left Atrial Pressure After Pediatric Heart Surgery: A Comparison Study With Measurements Obtained From Left Atrial Catheter

BACKGROUND

Correlation between ventricular end-diastolic pressure and pulsed Doppler and tissue Doppler-derived E/e' ratio has been widely reported in adults but scarcely studied in children with congenital heart diseases. This ratio is defined as the relationship between diastolic transmitral flow velocity (cm/s; E) and myocardial diastolic relaxation velocity (cm/s; e') in the lateral aspect of the mitral annulus. Our main objective was to ascertain whether a correlation existed between direct measurement of left atrial pressure and echocardiographic E/e' ratio in children after heart surgery.

METHODS

Prospective study including 27 consecutive children after pediatric heart surgery. Data were analyzed according to whether they were obtained within the first 72 hours following surgery or later on. Sensitivity, specificity, positive and negative predictive values, and areas under the receiver-operating characteristics curve of E/e' ratio in detection of left atrial pressure values ≥13 mm Hg were evaluated.

RESULTS

Forty-eight studies were conducted in 27 patients. Thirty-two studies were performed during the first 72 hours after heart surgery and 16 beyond the third day. Median patient age was 0.82 years (5 days-16 years). Median left atrial pressure values and E/e' measurements of the whole cohort (N = 48) were 12.0 and 10.2, respectively. Intraclass correlation index between left atrial pressure values and echocardiographic E/e' ratio was 0.35, 0.25 for studies performed within 72 hours, but 0.78 (P < .01) for those performed later. There was also a high positive predictive value, since in 13 (87%) of 15 studies with an E/e' ratio ≥13, the left atrial pressure was ≥13 mm Hg.

CONCLUSION

While echocardiographic E/e' ratio did not show a good correlation with left atrial pressure in the immediate postoperative period, the positive predictive value may suffice to aid clinicians in predicting elevated pressures.

Effect of anti-heart failure therapy on diastolic function in children with single-ventricle circulations

BACKGROUND

Children with functionally univentricular circulations have chronic volume loading of the systemic ventricle, potentially affecting ventricular function. Medications including angiotensin-converting enzyme inhibitors and β-blockers are used to treat ventricular dysfunction, despite limited evidence of their efficacy in this population.

OBJECTIVE

To determine the effects of angiotensin-converting enzyme inhibitors on elevated filling pressures in children with single ventricle physiology.

METHODS

We performed a single-centre, retrospective review of patients with single ventricle physiology who underwent multiple cardiac catheterisations between 1991 and 2013. Study population comprised of patients who commenced or had optimised dosing of angiotensin-converting enzyme inhibitors between assessments in response to high ventricular filling pressures. Patients undergoing interventions influencing loading conditions between assessments were excluded.

RESULTS

A total of 17 patients were identified, with dominant morphologic right ventricle in eight patients (47.1%). Among them, 11 (64.7%) were pre-Fontan and six (35.3%) were post-Fontan completion. Median inter-assessment interval was 9.4 months (range 7.3-19.1). There was a reduction in end-diastolic pressure from 13 to 10 mmHg (p=0.002), mean pulmonary artery pressure from 16 to 13 mmHg (p=0.049), and mean atrial pressure from 12 to 9 mmHg (p=0.001). There was one cardiac transplant, and there were no patient deaths at median follow-up after 31 months.

CONCLUSIONS

We observed a reduction in ventricular end-diastolic pressure, pulmonary artery pressure, and mean atrial pressure following treatment with angiotensin-converting enzyme inhibitors in patients with single ventricle physiology. Our study provides insights into the potential impact of anti-heart failure therapy in single ventricle circulations and calls for larger, controlled studies to assess for a therapeutic response.

Assessment of longitudinal systolic ventricular dysfunction and asynchrony using velocity vector imaging in children with a single right ventricle

Assessment of ventricular dysfunction and asynchrony is very important in predicting the outcome for children with a single right ventricle. However, the assessment is inaccurate and subjective because of the unusual ventricular shape. This study aimed to evaluate the feasibility and clinical value of velocity vector imaging for assessing longitudinal systolic ventricular dysfunction and intraventricular asynchrony in children with a single right ventricle. The study enrolled 36 children with a single right ventricle and 36 age-matched children with a normal heart. Peak systolic velocity, peak displacement, strain, strain rate, time to peak systolic velocity, and time to peak systolic strain were measured via velocity vector imaging using the Siemens Sequoia C512 echocardiography instrument. The maximum positive rate of ventricular pressure change (Max [dp/dt]) was obtained by cardiac catheterization for all the children with a single right ventricle. In the children with a single right ventricle, the maximal temporal differences and the standard deviations of the times to peak systolic velocity and peak systolic strain were higher (P < 0.01) than in the children with a normal heart. Moreover, the strain and strain rate values were significantly lower in all six segments (P < 0.05). The strain rate of the basal segment adjacent to the rudimentary chamber correlated best with Max (dp/dt) (r = 0.86; P < 0.01). Longitudinal systolic dysfunction and intraventricular asynchrony could be assessed accurately using velocity vector imaging in children with a single right ventricle.

Survey of how pediatric cardiologists noninvasively evaluate patients with hypoplastic left heart syndrome

BACKGROUND

The evaluation of right ventricular (RV) function is important in patients with hypoplastic left heart syndrome (HLHS). Echocardiographic qualitative grading has been the prevalent method used in the past, but newer technologies allowing for quantitative assessment of RV function may have changed this fact. The goal of this study was to determine the current routine noninvasive evaluation of patients with HLHS and what, if any, methods are used to assess systolic and diastolic function in this population.

METHODS

Web-based survey was conducted using various listservs. Timing of echocardiograms between surgical stages was assessed. Methods of assessing systolic and diastolic function were evaluated.

RESULTS

Two hundred seventy-seven physicians who averaged 12.8 ± 9.6 years removed from training responded. Largest percentage of respondents was echocardiographers (44.2%) in a university-based practice (73.3%) from North America (91.7%). There were 54.3% of respondents who performed echocardiograms monthly between stages I and II, 48.8% who performed echocardiograms every 6 months between stages II and III, and 67.0% who performed echocardiograms annually after stage III procedure. The main method for systolic grading was qualitative grading (95.5%) and for diastolic grading were tricuspid blood inflow velocities (56.8%). Qualitative grading was considered the method of choice for systolic grading for 38.8% of respondents and tissue Doppler velocities was the method of choice for diastolic grading for 35.3% of respondents. There were 4.0% of respondents who routinely perform a cardiac magnetic resonance imaging (cMRI) between stages I and II, 8.0% between stages II and III, and 24.2% after stage III procedure.

CONCLUSION

Variability in the noninvasive assessment of the RV in patients with HLHS continues to exist. Qualitative RV systolic assessment was still the predominant method used to assess function despite newer imaging techniques to allow for quantification. Future studies are needed to determine which values are most useful in reviewing function in this complex patient population.

Comparison of pressure-volume loop and echocardiographic measures of diastolic function in patients with a single-ventricle physiology

Echocardiographic measurements of diastolic function have not been validated against invasive pressure-volume loop (PVL) analysis in the single-ventricle population. The authors hypothesized that echocardiographic measures of diastolic function would correlate with PVL indices of diastolic function in patients with a single-ventricle physiology. The conductance-derived PVL measures of diastolic function included the isovolumic relaxation time constant (τ), the maximum rate of ventricular pressure decline (peak -dP/dt), and a measure of passive diastolic stiffness (μ). The echocardiographic measures included Doppler inflow patterns of the dominant atrioventricular valve (DAVV), tissue Doppler velocities (TDI) at the lateral (ventricular free wall) component of the DAVV annulus, and the TDI-derived isovolumic relaxation time (IVRT'). The correlation between PVL and echocardiographic measures was examined. The study enrolled 13 patients at various stages of surgical palliation. The median age of the patients was 3 years (range 3 months to 19 years). τ correlated well with Doppler E:A (r = 0.832; p = 0.005), lateral E:E' (r = 0.747; p = 0.033), and IVRT' (r = 0.831; p = 0.001). Peak -dP/dt also was correlated with IVRT' (r = 0.609; p = 0.036), and μ also was correlated with IVRT' (r = 0.884; p = 0.001). This study represents the first-ever comparison of diastolic echocardiographic and PVL indices in a single-ventricle population. The findings show that Doppler E:A, lateral E:E', and IVRT' correlate well with PVL measures of diastolic function. This study supports further validation of echocardiographic measures of diastolic function versus PVL measures of diastolic function in the single-ventricle population.

Echocardiographic evaluation of univentricular physiology and cavopulmonary shunts

The term univentricular heart (UH) defines complex congenital heart disease that lacks a pulmonic ventricular chamber either in the original anatomy or the final palliation. The prevalence of patients with this type of physiology continues to increase due to improved surgical palliative procedures. This review will outline the physiology, complications, and echocardiographic approach to image patients with palliated UH.

Comparison of echocardiographic and pressure-volume loop indices of systolic function in patients with single ventricle physiology: a preliminary report

BACKGROUND

Differences in ventricular geometry and physiology of patients with single ventricle anatomy complicate the application of traditional, noninvasive measurements of systolic function. We compared noninvasive measures of ventricular systolic function in single ventricle patients with invasive measures to evaluate their validity in this population.

METHODS

A secondary analysis of patients with single ventricle physiology enrolled in the multi-institutional research project, "multi-scale modeling of single ventricle hearts," was performed. Pressure-volume loops (PVLs) were recorded using microconductance catheters. Transthoracic echocardiogram and cardiac magnetic resonance imaging were performed on the same day. PVL indices of systolic function including end-systolic elastance (Ees), maximal rate of pressure increase (dP/dTmax), and stroke work indexed to end-diastolic volume (SW/EDV) were compared with noninvasive measures, including echocardiographic myocardial performance index (MPI), rate of pressure rise (AV valve dP/dT), isovolumic acceleration, longitudinal shortening fraction (longSF), and fractional area change (FAC).

RESULTS

Fifteen patients had PVLs available for analysis. Eleven had a dominant right ventricle, three were status poststage 1 repair, five had superior cavopulmonary anastomosis, and seven had a total cavopulmonary anastomosis. FAC correlated with Ees (r = 0.69, P < .01), SW/EDV (r = 0.64, P = .01), and dP/dTmax (r = 0.59, P = .03). LongSF correlated with dP/dTmax (r = 0.61, P = .02) MPI, AV valve dP/dT, and isovolumic acceleration did not correlate with pressure-volume loop indices of systolic function.

CONCLUSIONS

Obtaining PVLs via microconductance catheters can reliably be performed in the single ventricle population and serve as a method to validate echocardiographic indices in this high-risk population. Of the echocardiographic variables, FAC showed the best correlation with PVL indices. Future studies controlling for stage of palliation should be performed to further validate echocardiographic measures of systolic function in this patient population.

Atrial and ventricular mechanics in patients after Fontan-type procedures: atriopulmonary connection versus extracardiac conduit

BACKGROUND

Differences in systemic venous flow dynamics and energy losses exist in various Fontan-type procedures, which may affect atrial and ventricular filling. The aim of this study was to test the hypothesis that atrial and ventricular mechanics differ between two types of Fontan procedures, atriopulmonary connection (APC) and extracardiac conduit, which have distinctly different systemic venous hemodynamics.

METHODS

This was a cross-sectional, case-control study of 28 Fontan patients (13 with APC, 15 with extracardiac conduit) aged 19.8 ± 6.5 years and 26 healthy controls. Atrial and systemic ventricular myocardial deformation was determined using speckle-tracking echocardiography, while ventricular volumes and systolic dyssynchrony index were assessed using three-dimensional echocardiography.

RESULTS

Compared with controls, patients had significantly lower values of global ventricular longitudinal, circumferential, and radial systolic strain in all three directions, reduced systolic and early diastolic strain rates (SRs) in more than one dimension, lower ejection fractions, and worse ventricular dyssynchrony. For atrial deformation, patients had lower global and positive strain and conduit and reservoir SRs and delayed electromechanical coupling. Among patients, those with APC had significantly lower ventricular longitudinal strain and early diastolic SRs, worse ventricular dyssynchrony, and reduced atrial positive and negative strain and conduit and active contractile SRs. Atrial global strain (r = 0.60, P = .001) and conduit SR (r = 0.49, P = .008) correlated positively with systemic ventricular early diastolic SR.

CONCLUSIONS

Atrial and ventricular mechanics are impaired in patients after Fontan-type operation, which is worse with APC than extracardiac conduit.

The assessment of atrial function in single ventricle hearts from birth to Fontan: a speckle-tracking study by using strain and strain rate

BACKGROUND

Single ventricle (SV) exercise performance is impaired and limited by reduced ventricular preload reserve. The atrium modulates ventricular filling, and enhancement of atrial compliance can increase cardiac performance. We aimed to study atrial mechanics in SV hearts across staged surgical palliation compared with healthy children by using novel speckle-tracking echocardiography techniques.

METHODS

A cross-sectional study of 81 patients with SV (1 day to 6.5 years) at 4 stages of surgical palliation (presurgery, 22; prebidirectional cavopulmonary anastomosis, 23; pre-Fontan, 22; post-Fontan, 14). The dominant atrium was assessed with speckle-tracking echocardiography for active (εact), conduit (εcon), and reservoir (εres) strain; strain rate (SR); and εact/εres ratio before each stage of surgical palliation. Findings were compared with the left atrium of 51 healthy children (1 day to 5.5 years).

RESULTS

Single ventricle atrial size was increased (P < .01), and atrial εres was decreased (P < .01) compared with healthy controls. SV atrial εcon (P < .01) and SRcon (P < .0001) was decreased, increased εact persisted (P < .05), and εact/εres was increased (P < .001) between surgical stages. Although the expected maturational trend of increasing εcon, decreasing εact, and εact/εres occurred in SV, they lagged behind healthy maturational changes (P < .0001).

CONCLUSION

Single ventricle atrium is dilated, has deceased compliance, decreased early diastolic emptying, and increased reliance on active atrial contraction for ventricular filling. This deviates from normal early childhood maturational changes and appears to parallel those of an atrium facing early ventricular diastolic dysfunction.