Decline of Systolic and Diastolic 2D Strain Rate During Follow-Up of HLHS Patients After Fontan Palliation

Accurate assessment of ventricular function is particularly important in children with hypoplastic left heart syndrome (HLHS) after completion of the total cavopulmonary connection (TCPC). For this purpose, two-dimensional speckle tracking (2DST) is a promising technique as it does not depend on the angle of insonation or the geometry of the ventricle. The objective of this study was to assess changes in systolic and diastolic right ventricular (RV) function within a 5-year follow-up period of HLHS patients after TCPC using conventional and 2DST echocardiography. RV fractional area change (RVFAC), tricuspid annular plane systolic excursion (TAPSE), E/A, E/e′ and 2DST parameters [global longitudinal peak systolic strain (GS) and strain rate (GSRs), global strain rate in early (GSRe) and late (GSRa) diastole] of 40 HLHS patients were compared at 1.6 and at 5.1 years after TCPC. RVFAC, E/A, E/e′ and GS did not change, whereas TAPSE (13.7 ± 3.2 vs. 10.5 ± 2.4 mm/m², p < 0.001), GSRs (?1.56 ± 0.28 vs. ?1.35 ± 0.31 1/s, p < 0.001), GSRe (2.22 ± 0.49 vs. 1.96 ± 0.44 1/s, p = 0.004) and GSRa (1.19 ± 0.39 vs. 0.92 ± 0.39 1/s, p < 0.001) decreased significantly. Systolic and diastolic RV function parameters of HLHS patients decreased from 1.6 to 5.1 years after TCPC in our patients. Changes in global strain rate parameters may be signaling early RV dysfunction that is not detectable by traditional echocardiography. Further study is needed to verify this and to determine whether these changes are clinically relevant.     

Right Ventricle and Tricuspid Valve Function at Midterm After the Fontan Operation for Hypoplastic Left Heart Syndrome: Impact of Shunt Type

This study aimed to evaluate clinical outcomes including hemodynamics, right ventricle (RV) function, and tricuspid valve (TV) function in patients with hypoplastic left heart syndrome (HLHS) at midterm after completion of staged palliation based on the source of pulmonary blood flow provided at stage 1. The records of all patients with HLHS who completed Fontan palliation between 2001 and 2007 were retrospectively reviewed. The outcome variables were RV dysfunction, TV, and neo-atrioventricular (neo-AV) regurgitation (from latest echocardiogram), cardiac index (CI), pulmonary vascular resistance (PVR), pulmonary artery pressure (PAp), and right ventricular end-diastolic pressure (RVEDp) (from latest catheterization). Clinical status was obtained from medical records and by contact with the referring cardiologist if necessary. Of 118 patients undergoing a Fontan for HLHS, 116 had a fenestrated lateral tunnel and 2 had an extracardiac conduit. At the time of stage 1 palliation, 36 patients had a right ventricle-to-pulmonary artery (RV-PA) conduit, and 82 patients had a modified Blalock-Taussig shunt (mBTS). All the patients except one who died of sepsis on extracorporeal membrane oxygenation (ECMO) survived the Fontan operation and were discharged home. At a mean follow-up post-Fontan period of 28.4 months (range, 0.16-95.3 months), three patients had died (2 on the transplantation list and 1 from pulmonary vein stenosis), and one patient had the Fontan circulation taken down. No patient had a heart transplantation. A follow-up echocardiogram was performed for 115 patients (after a mean of 15.6 months for RV-PA and 32.1 months for BTS), and 66 patients underwent a post-Fontan catheterization (after a mean of 15.8 months for RV-PA and 29.3 months for BTS). The hemodynamic results for RV-PA conduit versus BTS were a CI of 3.4 ± 0.8 versus 3.4 ± 1.2, a PVR of 1.8 ± 0.7 versus 1.7 ± 0.8, a PAp of 14.3 ± 3.1 versus 14.2 ± 4.5, and an RVEDp of 7.1 ± 3.3 versus 8.9 ± 5.3. No statistically significant differences were found between shunt types regarding survival or degree of RV dysfunction or in terms of neo-AV regurgitation, CI, PVR, PAp, RVEDp, or rhythm problems. Patients in the BTS group required more tricuspid valvuloplasties and had more tricuspid regurgitation at follow-up evaluation. The patients in the RV-PA group had more PA interventions. In conclusion, the contemporary results after Fontan palliation for HLHS were excellent. At the midterm follow-up evaluation, outcomes and hemodynamic data were similar between shunt types. However, the patients in the BTS group exhibited more tricuspid regurgitation, and the patients in the RV-PA group had increased pulmonary artery interventions.     

Ratio of Early Diastolic Tricuspid Inflow to Tricuspid Lateral Annulus Velocity Reflects Pulmonary Regurgitation Severity but Not Right Ventricular Diastolic Function in Children With Repaired Tetralogy of Fallot

The current study assessed relationships between the ratio of early diastolic tricuspid inflow to tricuspid lateral annular velocity (tricuspid E/e′) and right ventricular (RV) function in children after tetralogy of Fallot (TOF) repair. The RV function of 25 asymptomatic children with surgically repaired TOF (age 3.3 ± 2.0 years) was assessed by echocardiography and cardiac catheterization. Right ventricular end-diastolic pressure and volume (RVEDP and RVEDV), systolic pressure, and ejection fraction, as well as mean pulmonary arterial pressure, mean right atrial pressure (RAP), and the severity of both pulmonary regurgitation (PR) and tricuspid regurgitation (TR) were assessed in terms of the contribution to tricuspid E/e′. Univariate analysis discovered a relationship between tricuspid E/e′ and RVEDV (R ² = 0172), pressure half-time of PR (PR-PHT) (R ² = 0.173), and TR grade (R ² = 0.145) (p < 0.01 for each). After multivariate adjustment, PR-PHT was significantly associated with tricuspid E/e′ (β = 0.210; p < 0.001). Tricuspid E/e′ was not significantly associated with RVEDP or RAP. In conclusion, tricuspid E/e′ does not indicate RV diastolic function but reflects the severity of PR in asymptomatic children after TOF repair.     

Evaluation of Cardiac Functions and Atrial Electromechanical Delay in Children With Adenotonsillar Hypertrophy

Deterioration of the right ventricular (RV) functions and the increase in the pulmonary arterial pressure (PAP) of children with moderate to severe adenotonsillar hypertrophy (ATH) have been well described. In addition to these complications, this study aimed to investigate the influence of ATH on the conduction system. The study investigated 46 patients with a diagnosis of ATH and 46 healthy control subjects. Conventional echocardiography, P-wave dispersion (Pd), tissue Doppler imaging (TDI) findings, and atrial electromechanical delay (AED) were compared between the patients and the control subjects before and after adenotonsillectomy. The maximum P-wave duration and Pd were significantly higher in the patients than in the control subjects (p < 0.001). The patient group showed significantly greater RV end-diastolic dimension (p = 0.01), right atrial area (p < 0.001), and mean PAP (p = 0.03) but lower E/A ratios for the mitral (p = 0.04) and tricuspid (p = 0.01) valves and a shorter pulmonary flow trace acceleration time (p = 0.03). The tricuspid annular-plane systolic excursion was similar between these groups (p = 0.21). In the patient group, TDI studies showed significantly lower E′/A′ ratios for the tricuspid lateral (p = 0.006) and mitral septal (p = 0.003) segments than in the control group. The myocardial performance index was lower for the mitral lateral, mitral septal, and tricuspid lateral segments in patient group (p < 0.001). Similarly, AED was prolonged in the patient group at all three segments (p < 0.001). Also, the patient group showed a significantly longer interatrial (p = 0.03) and intraatrial (p = 0.04) electromechanical delay. However, all the electro- and echocardiographic parameters were similar between the patients and the control subjects after adenotonsillectomy (p > 0.05). The prolongations in P-wave duration, Pd, and inter- and intraatrial electromechanical delays were first shown in this population. The cardiac changes induced by ATH-associated hypoxia may facilitate arrhythmias during the long term.     

Right-Ventricular Global Longitudinal Strain May Predict Neo-Aortic Arch Obstruction After Norwood/Sano Procedure in Children With Hypoplastic Left Heart Syndrome

Neo-aortic arch obstruction (NAAO) is a common complication following the Norwood/Sano procedure (NP) for hypoplastic left heart syndrome (HLHS) and is associated with increased morbidity and mortality. However, there is currently no objective method for predicting which patients will develop NAAO. This study was designed to test the hypothesis that hemodynamic changes from development of NAAO after NP in patients with HLHS will lead to changes in myocardial dynamics that could be detected before clinical symptoms develop with strain analysis using velocity vector imaging. Patients with HLHS who had at least one cardiac catheterization after NP were identified retrospectively. Strain analysis was performed on all echocardiograms preceding the first catheterization and any subsequent catheterization performed for intervention on NAAO. Twelve patients developed NAAO and 30 patients never developed NAAO. Right ventricular strain was worse in the group that developed NAAO (?6.2 vs. ?8.6 %, p = 0.040) at a median of 59 days prior to diagnosis of NAAO. Those patients that developed NAAO following NP were significantly younger at the time of first catheterization than those that did not develop NAAO (92 ± 50 vs. 140 ± 36 days, p = 0.001). This study demonstrates that right ventricular GLS is abnormal in HLHS patients following NP and worsening right ventricular strain may be predictive of the future development of NAAO.     

Clinical Outcomes and Resource Use for Infants With Hypoplastic Left Heart Syndrome During Bidirectional Glenn: Summary From the Joint Council for Congenital Heart Disease National Pediatric Cardiology Quality Improvement Collaborative Registry

The National Pediatric Cardiology Quality Improvement Collaborative (NPC-QIC) registry captures information on interstage management of infants with hypoplastic left heart syndrome (HLHS). The purpose of this study was to identify interstage risk factors for increased resource use and adverse outcomes during bidirectional Glenn (BDG) hospitalization. All infants in the NPC-QIC registry (31 United States hospitals) undergoing BDG surgery were included (December 2009 to August 2010). Patient demographics, interstage variables, operative procedures, and complications were recorded. Days of hospitalization, ventilation, inotrope use, and complications were surrogates of resource use. Logistic regression analysis determined the associations between predictor variables and resource use. Of 162 infants, 105 (65 %) were males. At BDG, the median age was 155 days (range 78–128), mean weight-for-age z-score was ?1.6 ± 1.1, mean length-for-age z-score was ?1.5 ± 1.7, and mean preoperative oxygen saturation was 78 % ± 7 %. Caloric recommendations were met in 60 % of patients, and 85 % of patients participated in a home-surveillance program. Median days of intubation, inotrope use, and hospitalization were 1, 2, and 7, respectively. There were 4 post-BDG deaths and 55 complications. In multivariate analysis, lower weight-for-age z-score, female sex, and aortic atresia with mitral stenosis were associated with a higher risk of BDG complications. Meeting caloric recommendations before BDG was associated with fewer hospitalization days. Lower weight-for-age z-score was an independent and potentially modifiable risk factor for BDG complications. HLHS infants who met caloric recommendations before BDG had a lower duration of hospitalization at BDG. These data justify targeting nutrition in interstage strategies to improve outcomes and decrease costs for patients with HLHS.     

Echocardiographic Evaluation of Ventricular Function in Children With Pulmonary Hypertension

Although described in adults, it remains unclear whether ventricular dysfunction exists in pediatric patients with pulmonary hypertension (PHN). The goal of this study was to identify differences in echocardiographic indices of ventricular function among pediatric PHN patients. From 2009 to 2011, pediatric PHN patients with normal intracardiac anatomy and age-matched controls (1:3 ratio) were enrolled in this retrospective case–control study. Diagnosis of PHN was based on tricuspid regurgitation velocity or septal position estimating right-ventricular (RV) pressure >50 % systemic. Measures of RV and left ventricular systolic and diastolic function, including tissue Doppler imaging (TDI) of the mitral annulus (MA) and tricuspid annulus (TA), were compared. Enrollees included 25 PHN patients and 75 age-matched controls (mean age 7.5 years [range 1 day to 19 years]). Parameters of RV systolic and diastolic function were worse in PHN patients. Compared with controls, PHN patients had significantly decreased tricuspid valve inflow ratio, decreased TA TDI early diastolic velocities, decreased systolic velocities, increased tricuspid E/E’ ratio (all p < 0.01) and increased myocardial performance index. In an age-stratified analysis, TDI measures in PHN patients <1 year of age were similar to controls, whereas differences in TA TDI velocities and MA TDI velocities were noted in patients ≥1 year of age. Abnormalities in Doppler echocardiographic indices of ventricular systolic and diastolic function were identified in pediatric PHN patients and were more prominent with older age. These indices are promising for serial noninvasive monitoring of disease severity, but further correlation with catheterization-derived measures is needed.     

Leftward Displacement of Septum Primum in Hypoplastic Left Heart Syndrome

Embryologic development of atrial septum primum antedates formation of the atrioventricular and semilunar valves. Leftward displacement of the superior attachment of septum primum (LDSP) has only been described in hypoplastic left heart syndrome (HLHS). This study reports the frequency of LDSP in HLHS and correlates LDSP with other echocardiographic features of HLHS. Preoperative echocardiograms for 72 consecutive patients with classic HLHS from 1996 to 2002 at Children’s Hospital of Wisconsin were reviewed. One patient was excluded for inadequate imaging. Data for the 71 patients included the following: size, location, and Doppler gradient across the atrial septal defect (ASD); location of attachment of septum primum; size and patency of the aortic valve (AoV) annulus; size and patency of the mitral valve (MV) annulus; ascending aorta diameter (AAD); and left-ventricular end diastolic dimension (LVEDD). Patients were categorized into three groups: aortic atresia/mitral atresia (AA/MA), aortic atresia/mitral stenosis (AA/MS), and aortic stenosis/mitral stenosis (AS/MS). LDSP was seen in 46 of 71 patients (64 %). By diagnostic group, 32 of 35 patients with AA/MA had LDSP (91 %) compared with 10 of 19 AA/MS patients (53 %) and 4 of 17 AS/MS patients (24 %), p < 0.05. AoV patency was seen in 4 of 46 (9 %) patients with LDSP compared with 13 of 25 (52 %) patients with normal atrial attachment, p < 0.005. Mean left heart dimensions in infants with LDSP compared with normal attachment were as follows: AoV annulus 2.24 versus 3.83 mm, AAD 2.34 versus 4.1 mm, MV annulus 3.21 versus 6.48 mm, and LVEDD 6.38 versus 13.83 mm. By two-way analysis of variance of diagnostic category versus atrial septal attachment with interaction, MV annulus and AAD were independently predicted smaller by LDSP versus normal atrial attachment, p < 0.05. Nonsignificant factors included AoV annulus, LVEDD, ASD size, and Doppler gradient. LDSP correlates with more severe maldevelopment of the left heart in patients with HLHS. Because formation of septum primum precedes development and growth of the intracardiac valves, we speculate that LDSP may be an initiating event in the development of HLHS. In addition, prenatal identification of LDSP may help direct planning of potential in utero therapies.     

Pulmonary Artery Dilation and Right Ventricular Function in Acute Kawasaki Disease

Coronary artery inflammation and aneurysm formation are the most common complications of Kawasaki disease (KD). Valvulitis and myocarditis are also well described and may lead to valvar regurgitation and left ventricular dysfunction. However, functional changes in the right heart have rarely been reported. We noted several acute KD patients with dilated pulmonary arteries (PA) and thus sought to systematically characterize PA size and right-heart function in an unselected cohort of KD patients cared for at a single clinical center. Clinical, laboratory, and echocardiographic data from 143 acute KD subjects were analyzed. PA dilation was documented in 23 subjects (16.1 %); these subjects had higher median right ventricle myocardial performance index (RV MPI), higher ratio of early tricuspid inflow velocity to tricuspid annular early diastolic velocity (TV E/e′), and lower median TV e′ velocity compared to the non-PA dilation group (0.50 vs 0.38 p < 0.01, 4.2 vs 3.6 p < 0.05, and 13.5 vs 15.2 cm/s p < 0.01, respectively). Almost all subjects with PA dilation had improved PA Z-score, RV MPI, and TV E/e′ in the subacute phase (p < 0.01). There were no significant differences in indices of left ventricle function between PA dilation group and non-PA dilation group. In summary, PA dilation was documented in 16 % of acute KD subjects. These subjects were more likely to have echocardiographic indices consistent with isolated RV dysfunction that improved in the subacute phase. The long-term consequence of these findings will require longitudinal studies of this patient population.     

Tricuspid Annular Plane Systolic Excursion Does Not Correlate With Right Ventricular Ejection Fraction in Patients With Hypoplastic Left Heart Syndrome After Fontan Palliation

Tricuspid annular plane systolic excursion (TAPSE) reflects longitudinal myocardial shortening, the main component of right ventricular (RV) contraction in normal hearts. To date, TAPSE has not been extensively studied in patients with hypoplastic left heart syndrome (HLHS) and systemic RVs after Fontan palliation. This retrospective study investigated HLHS patients after Fontan with cardiac magnetic resonance (CMR) performed between 1 January 2010 and 1 August 2012 and transthoracic echocardiogram (TTE) performed within 6 months of CMR. The maximal apical displacement of the lateral tricuspid valve annulus was measured on CMR (using four-chamber cine images) and on TTE (using two-dimensional apical views). To create TTE–TAPSE z-scores, published reference data were used. Intra- and interobserver variability was tested with analysis of variance. Inter-technique agreement of TTE and CMR was tested with Bland–Altman analysis. In this study, 30 CMRs and TTEs from 29 patients were analyzed. The age at CMR was 14.1 ± 7.1 years, performed 11.9 ± 7.8 years after Fontan. For CMR–TAPSE, the intraclass correlation coefficients for inter- and intraobserver variability were 0.89 and 0.91, respectively. The TAPSE measurements were 0.57 ± 0.2 cm on CMR and 0.70 ± 0.2 cm on TTE (TTE–TAPSE z score, ?8.7 ± 1.0). The mean difference in TAPSE between CMR and TTE was ?0.13 cm [95 % confidence interval (CI) ?0.21 to ?0.05], with 95 % limits of agreement (?0.55 to 0.29 cm). The study showed no association between CMR–TAPSE and RVEF (R = 0.08; p = 0.67). In patients with HLHS after Fontan, TAPSE is reproducible on CMR and TTE, with good agreement between the two imaging methods. Diminished TAPSE suggests impaired longitudinal shortening in the systemic RV. However, TAPSE is not a surrogate for RVEF in this study population.     

Hemodynamic Assessment in Patients with One-and-a-Half Ventricle Repair Revealed by Four-Dimensional Flow Magnetic Resonance Imaging

We report hemodynamic findings in two patients with pulmonary atresia and intact ventricular septum (PAIVS) after “one-and-a-half ventricle repair” and placement of a bidirectional Glenn shunt using four-dimensional (4D) flow magnetic resonance imaging. Quantification of flow and analysis of flow patterns revealed the hemodynamic “battle” between the right ventricle (RV) and the Glenn shunt. Moreover, with a novel approach we calculated during Glenn anastomosis the flow distribution from the superior vena cava (SVC) to the pulmonary arteries. Our results showed a highly asymmetric flow distribution, with most of the flow from the SVC toward the RV and not to the lungs. The evidence provided by 4D flow demonstrates poor efficiency of this system and suggests that both patients might benefit from adding an artificial pulmonary valve to avoid right heart failure.     

Assessment of Atrial Electromechanical Delay Using Tissue Doppler Echocardiography in Children with Asthma

Right ventricular (RV) dysfunction, pulmonary hypertension, atrial enlargement, and cor pulmonale may be associated with asthma. These pathological conditions may disturb the electrophysiological properties of the right atrium. This study investigated the atrial electromechanical delay and P-wave dispersion (PWD) in patients with asthma. Thirty-four children aged 8–16 years who were being followed up for asthma constituted the patient group, and 34 age- and body mass index-matched patients constituted the control group. Both groups underwent RV tissue Doppler measurements, intra-right atrial conduction time (IRCT-echo) determination, intra-left atrial conduction time (ILCT-echo) determination, inter-atrial conduction time (IACT-echo) determination, and PWD measurement. The IRCT-echo (14.38 ± 5.46 and 8.20 ± 3.90 ms; p < 0.001) and IACT-echo (28.97 ± 6.58 and 22.79 ± 6.28 ms; p < 0.001) were higher in patients with asthma than in the control group. The PWD (44.58 ± 17.51 and 38.11 ± 13.50 ms; p = 0.09), maximum P-wave duration (87.94 ± 18.20 and 82.44 ± 16.36 ms, p = 0.19), minimum P-wave duration (43.58 ± 9.95 and 44.79 ± 9.13 ms; p = 0.60), and ILCT-echo (15.88 ± 5.40 and 14.58 ± 4.94 ms; p = 0.30) were similar between the two groups. The IRCT-echo was positively correlated with the isovolumetric relaxation time of the lateral tricuspid annulus (r = 0.60; p < 0.001) and with the myocardial performance index of the lateral tricuspid annulus (r = 0.59; p < 0.001) in patients with asthma. The IRCT-echo and IACT-echo were higher in patients with asthma than in the control group. The deterioration of the electrophysiological properties of the right atrium may result in a risk of atrial fibrillation in patients with asthma.     

Right Heart Function of Fetuses and Infants with Large Ventricular Septal Defect: A Longitudinal Case–Control Study

The objective of this study was to detect the effect of a large ventricular septal defect (VSD) on right ventricular function before and after birth. All consecutive children with large VSD who were born in our hospital between January 2013–February 2016 and followed up throughout early infancy, and who lacked malformations or chromosomal abnormalities, were identified by a retrospective review of the medical records and included in this retrospective longitudinal case–control study (n = 30). Thirty normal control cases with an equivalent gestational age and gender served as controls. Tricuspid annular plane systolic excursion (TAPSE), right ventricle (RV) Tei index, and tricuspid E/E _m were measured in the fetal, neonatal (day 1–28), and infant (day 29–70) periods. In all periods, the VSD and control groups did not differ in TAPSE values, but VSD associated with higher Tei indices and tricuspid E/E _m values (in the fetal period: VSD group RV Tei was 0.48 ± 0.12 and E/E _m was 11.84 ± 1.53, control group RV Tei was 0.42 ± 0.16 and E/E _m was 10.16 ± 1.61; in neonatal period: VSD group RV Tei was 0.41 ± 0.17 and E/E _m was 12.21 ± 1.59, control group RV Tei was 0.30 ± 0.13 and E/E _m was 7.20 ± 1.28; in the infant period: VSD group RV Tei was 0.39 ± 0.09 and E/E _m was 11.89 ± 2.80, control group RV Tei was 0.28 ± 0.12 and E/E _m was 5.26 ± 1.90, all p < 0.05). In the fetal and neonatal periods, TAPSE correlated negatively with Tei index and tricuspid E/E _m in both groups. However, in the infant period, only the control group exhibited correlations between TAPSE and Tei index or tricuspid E/E _m. Tei index correlated positively with tricuspid E/E _m in both groups in all three periods. The VSD group had smaller correlation coefficients than the control group. Large VSD may already start to impair RV diastolic and global function before birth. This impairment continued and increased after birth. These changes did not associate with obvious RV longitudinal systolic function impairment. Large VSD mainly affected RV function by decreasing diastolic function and myocardial performance.     

Right Ventricular Myocardial Performance Index Is Decreased With Severe Pressure-Overload Cardiac Hypertrophy in Young Rats

Although the right ventricular (RV) myocardial performance index (MPI) usually is increased in the presence of RV dysfunction and pressure overload, debate continues over the correlation between the RV MPI and functional derangement in patients with RV pressure-overload congenital heart disease (CHD). To address this controversy, this study took serial measurements of the RV MPI in addition to invasive RV hemodynamic measurements during the acute stage of mild to severe pressure overload. Right ventricle pressure overload was induced by partial pulmonary arterial banding (PAB) in 3-week-old rats. The rats were divided into two groups: mild pulmonary stenosis (PS) group (20–40 % stenosis; n = 20) and severe PS group (40–70 % stenosis; n = 28). Sham-treated animals (sham group; n = 30) underwent the same surgical procedure without PAB. Pressure-overload RV hypertrophy was documented by weighing the heart, by evaluating echocardiograms, and by evaluating cardiac hypertrophy-associated gene expression. The RV MPI was checked 1, 2, 3, 5, and 8 weeks after PAB. The MPI was calculated as the sum of the isovolumic contraction time and the isovolumic relaxation time (IRT) divided by the ejection time. The RV MPI of the mild PS group did not differ significantly from that of the sham group. The RV MPI of the severe PS group, however, was lower than that of the sham group (0.27 ± 0.01 vs 0.29 ± 0.01) 2 to 8 weeks after PAB: 0.19 ± 0.01 at 2 weeks (P < 0.001), 0.16 ± 0.01 at 3 weeks (P < 0.001), 0.20 ± 0.01 at 5 weeks (P = 0.021), and 0.18 ± 0.01 at 8 weeks (P < 0.001) after PAB. The decreased RV MPI was associated with decreased IRT and increased ejection time. RV hypertrophy contributes to the decrease in the RV MPI in the severe pressure-overload condition.     

Clinical Course and Interstage Monitoring After the Norwood and Hybrid Procedures for Hypoplastic Left Heart Syndrome

Infants with hypoplastic left heart syndrome (HLHS) are at risk for interstage morbidity and mortality, especially between the first and second surgical stages after the Norwood and hybrid procedures. This study compared the morbidity and mortality of patients treated by either the Norwood or the hybrid procedure for HLHS between the first and second stages who were undergoing interstage monitoring. Between October 2008 and December 2011, 26 infants (14 boys) with HLHS (n = 16) and other univentricular heart malformations with aortic arch anomaly (n = 10) were scheduled for interstage monitoring after Norwood I (n = 12) and hybrid (n = 14) procedures. Three infants (11.5 %) died after first-stage palliation (one hybrid patient and two Norwood patients), and three infants (11.5 %) died after second-stage palliation (two hybrid patients and one Norwood patient) (p = 0.83), all after early second-stage surgery (<90 days). The Norwood I and hybrid procedures did not differ in terms of overall mortality (23 %) (three hybrid and three Norwood patients; p = 1.00). Seven infants (26.9 %) could not be discharged from the hospital due to hemodynamic instability and were referred for early second-stage surgery (<90 days). After the first stage, the invasive reevaluation rate before discharge was high (53.8 %), with cardiac catheterizations for 8 of 14 patients after the hybrid procedure and for 6 of 12 patients after the Norwood procedure (p = 0.69). A total of 11 reinterventions were performed (eight by catheter and three by surgery). Of the eight catheter reinterventions, five were performed for hybrid patients (p = 0.22). For 14 infants, 89 days (range 10–177 days) of interstage monitoring were scheduled. One infant (3.9 %) died during the interstage monitoring. The findings showed a breach of the physiologic criteria for interstage monitoring in seven infants (50 %) after 10 days (range 4–68 days) (five hybrid and two Norwood patients), leading to rehospitalization and catheterization for six patients (four hybrid and two Norwood patients), requiring interventions for two patients (patent arterial duct stent dilation, and atrial septal defect stenting, all for hybrid patients). Overall, three of the seven patients with red flag events of interstage monitoring were candidates for early second-stage surgery. In conclusion, morbidity among infants treated for HLHS remains high, either before or after hospital discharge, emphasizing the need of interstage monitoring programs. Despite retrograde aortic flow in infants with HLHS after the hybrid procedure, the mortality rate was comparable between the two groups. Mortality occurs after early second-stage surgery (<90 days).     

Effect of Ventriculotomy on Right-Ventricular Remodeling in Hypoplastic Left Heart Syndrome: A Histopathological and Echocardiography Correlation Study

The objective of this study was to compare histopathological changes in hypoplastic left heart syndrome right ventricles (RV) of patients undergoing Sano and modified Blalock–Taussig (MBT) shunt and correlate them with echocardiographic findings. Myocardial tissue samples were obtained from hearts with Sano or MBT shunts after transplantation or at autopsy. Histologic sections were reviewed manually and by automated digital image analysis. Velocity vector imaging was performed on echocardiogram images obtained before transplant or death. All of these parameters were compared between the Sano and MBT shunt cohorts. A total of 14 specimens (7 Sano and 7 MBT shunt) were studied. Median age at transplant/death of Sano and MBT shunt cohorts was 11 (range 2–41) and 8 months (range 2–200), respectively. All Sano specimens had a scar at ventriculotomy site, and the mean scar area was 6.2 ± 3.3 cm². Compared with remote RV free wall, myocardium bordering the scar showed increased fibrosis (34 ± 16 % vs. 28 ± 14 %, p = 0.04) and thinning (0.8 ± 0.9 vs. 5.3 ± 0.8 mm; p < 0.001), which did not regress with time. The Sano ventriculotomy site showed significantly decreased velocity, strain, and strain rate compared with the corresponding contralateral segment. No focal scarring or regional hypokinesia was seen in the MBT shunt cohort. This is the first study to demonstrate histopathological features of ventriculotomy-associated RV myocardial scarring and myocardial thinning. The scarred ventriculotomy site showed decreased segmental myocardial deformation after Norwood with Sano shunt.     

Current Outcomes of Hypoplastic Left Heart Syndrome With Restrictive Atrial Septum: A Single-Center Experience

Advances in the management of hypoplastic left heart syndrome (HLHS) have resulted in improved survival. However, short and long-term mortality in patients with a restrictive atrial septum remains high. All neonates diagnosed with HLHS from 2003 to 2010 at our institution were evaluated. Patients who underwent atrial septostomy within the first 72 h conformed the restrictive atrial septum group (HLHS-RS). Patients with a non-restrictive communication (HLHS-NRS) formed the control group. Outcomes and survival status were determined from review of medical records. Of the 141 newborns diagnosed with HLHS, 20 (14 %) required intervention for a restrictive atrial septum. Procedural success was achieved in 17/20 (85 %) patients. Complications occurred in ten procedures, two of which were life threatening. No procedural deaths occurred. Overall median follow up was 35.5 months (0.4–104). Initial hospitalization survival was 16/20 (80 %) for the HLHS-RS group and 114/121(94 %) for the HLHS-NRS (p = 0.028). Twenty (14 %) patients were lost to follow up and 9 (6 %) underwent heart transplant. Overall survival was 10/16 (62 %) for HLHSRS patients and 77/95 (81 %) for HLHS-NRS (p = 0.1). Survival after initial discharge was 10/12 (83 %) for the HLHS-RS group and 77/88 (87 %) for the HLHS-NRS (p = 0.67). No predictors for HLHS-RS outcome were identified. Mortality at first-stage palliation in HLHS neonates with a restrictive atrial septum remains higher than in those with an unrestrictive communication. However, survival after initial hospital discharge is similar.     

Assessment of Ventricular Functions by Tissue Doppler Echocardiography in Children with Asthma

Patients with asthma develop pulmonary hypertension due to recurrent hypoxia and chronic inflammation, leading to right heart enlargement with ventricular hypertrophy. Patients with severe asthma can experience cor pulmonale later in life, but little is known about ventricular function during the early stages of the disease. This study aimed to investigate ventricular functions in asymptomatic children with asthma as detected by conventional echocardiography and tissue Doppler echocardiography (TDE). Fifty-one pediatric patients (mean age 10.4 ± 2.2 years) with asthma and 46 age- and sex-matched healthy children (mean age 10.9 ± 2.4 years) were studied. All subjects were examined by conventional echocardiography and TDE, and they had pulmonary function tests on spirometry. The right-ventricular (RV) wall was statistically (p = 0.01) thicker among asthmatic patients (4.7 ± 1.5 mm) compared with healthy children (3.6 ± 0.4 mm). However, conventional pulsed-Doppler indices of both ventricles did not differ significantly between asthmatic patients and healthy children (p > 0.05). The results of TDE examining RV diastolic function showed that annular peak velocity during early diastole (E′), annular peak velocity during late diastole (A′) (16.4 ± 1.8 and 5.1 ± 1.4 cm/s, respectively), E′/A′ ratio (3.2 ± 0.7), isovolumetric relaxation time (67.7 ± 10.2 ms) and myocardial performance index (48.1 % ± 7.0 %) of the lateral tricuspid annulus among asthmatic patients differed significantly (p = 0.01) from those of healthy children (13.2 ± 2.3, 8.2 ± 2.0 cm/s, 1.6 ± 0.5, 46.2 ± 8.7 ms, and 42.0 % ± 5.7 %, respectively). Only peak expiratory flow (PEF) rate from the pulmonary function tests was negatively correlated with the E′/A′ ratio of the tricuspid annulus (r = ?0.38, p = 0.01). This study showed that although the findings of clinical and conventional echocardiography were apparently normal in children with asthma, TDE showed subclinical dysfunction of the right ventricle, which is negatively correlated with PEF. These findings signify the diagnostic value of TDE in the early detection and monitoring of such deleterious effects among asthmatic patients.     

Altered Right Ventricular Function in the Long-Term Follow-up Evaluation of Patients After Delayed Aortic Reimplantation of the Anomalous Left Coronary Artery From the Pulmonary Artery

This study aimed to evaluate regional and global ventricular functions in the long term after aortic reimplantation of the anomalous left coronary artery from the pulmonary artery (ALCAPA) and to assess whether the time of surgical repair influences ventricular performance.The study examined 20 patients with a median age of 15 years (range 3–37 years) who had a corrected ALCAPA and 20 age-matched control subjects using echocardiography and tissue Doppler imaging (TDI). The median follow-up period after corrective surgery was 6 years (range 2.6–15 years). Seven patients underwent surgery before the age of 3 years (early-surgery group), whereas 13 patients had surgery after that age (late-surgery group). The TDI-derived myocardial strain of the interventricular septum (IVS), lateral wall of the left ventricle (LV), and lateral wall of the right ventricle (RV) in the basal and mid regions were examined, and a mean was calculated. The pulsed Doppler-derived Tei index was used to assess global left ventricular function. No significant differences were found between the early-surgery group and the control group regarding the regional myocardial strain or the Tei index. Compared with the early-surgery group, the late-surgery group had a significantly higher Tei index (mean 0.37; range 0.31–0.42 vs. mean 0.52; range 0.39–0.69; p < 0.005), a lower strain percentage of the lateral wall of the LV (mean 29; range 17–30 vs. mean 9; range 7–23), IVS (mean 23; range 21–31 vs. mean 19; range 13–25), and lateral wall of the RV (mean 23; range 21–31 vs. mean 19; range 13–25). The age at operation correlated significantly with the Tei index (r = 0.84, p < 0.001) and inversely with the mean strain of the lateral wall of the LV (r = ?0.53, p = 0.028), IVS (r = ?0.68, p = 0.003), and lateral wall of the RV (r = ?0.68, p = 0.003). At the midterm follow-up evaluation after corrective surgery of ALCAPA, not only the left but also the right ventricular function seemed to be affected in patients with delayed diagnosis and late surgical repair but preserved among the younger patients with early diagnosis and corrective surgery.     

Tissue Doppler Imaging Detects Impaired Biventricular Performance Shortly After Congenital Heart Defect Surgery

Cardiac surgery with cardiopulmonary bypass is associated with the development of a systemic inflammatory response, which can lead to myocardial damage. However, knowledge concerning the time course of ventricular performance deterioration and restoration after correction of a congenital heart defect (CHD) in pediatric patients is sparse. Therefore, the authors perioperatively quantified left ventricular (LV) and right ventricular (RV) performance using echocardiography. Their study included 141 patients (ages 0–18 years) undergoing CHD correction and 40 control subjects. The study assessed LV systolic performance (fractional shortening) and diastolic performance (mitral Doppler flow) in combination with RV systolic performance [tricuspid annular plane systolic excursion (TAPSE)] and diastolic performance (tricuspid Doppler flow). Additionally, systolic (S′) and diastolic (E′, A′, E/E′) tissue Doppler imaging (TDI) measurements were obtained at the LV lateral wall, the interventricular septum, and the RV free wall. Echocardiographic studies were performed preoperatively, 1 day postoperatively, and at hospital discharge after 9 ± 5 days. Although all LV echocardiographic measurements showed a deterioration 1 day after surgery, only LV TDI measurements were impaired in patients at discharge versus control subjects (S′: 5.7 ± 2.0 vs 7.1 ± 2.7 cm/s; E′: 9.8 ± 3.9 vs 13.7 ± 5.1 cm/s; E/E′: 12.2 ± 6.4 vs 8.8 ± 4.3; p < 0.05). In the RV, TAPSE and RV TDI velocities also were impaired in patients at discharge versus control subjects (TAPSE: 9 ± 3 vs 17 ± 5 mm; S′: 5.2 ± 1.7 vs 11.4 ± 3.4 cm/s; E′: 7.3 ± 2.5 vs 16.3 ± 5.2 cm/s; E/E′: 12.5 ± 6.8 vs 4.8 ± 1.9; p < 0.05). Furthermore, longer aortic cross-clamp times were associated with more impaired postoperative LV and RV performance (p < 0.05). In conclusion, both systolic and diastolic biventricular performances were impaired shortly after CHD correction. This impairment was detected only by TDI parameters and TAPSE. Furthermore, a longer-lasting negative influence of cardiopulmonary bypass on myocardial performance was suggested.