Sildenafil has been reported to improve exercise capacity in Fontan patients, but the physiologic mechanisms behind these findings are not completely understood. The objective of this study was to study the acute effect of sildenafil on pressure–volume loop (PVL) measures of ventricular function in Fontan patients. Patients after Fontan operation who were presenting for a clinically indicated catheterization were enrolled. Patients were randomized in a double-blinded fashion to receive placebo (n = 9) or sildenafil (n = 10) 30–90 min prior to catheterization. PVLs were recorded using microconductance catheters at baseline and after infusion of dobutamine (10 mcg/kg/min). The primary outcome was change in ventriculoarterial (VA) coupling. For the entire cohort, VA coupling trended toward improvement with dobutamine (1.4 ± 0.4 to 1.8 ± 0.9, p = 0.07). End-systolic elastance showed improvement (2.6 ± 0.9 to 3.8 ± 1.4 mmHg m2/ml, p < 0.01) with dobutamine infusion. The cohorts had similar VA coupling at baseline (p = 0.32), but the sildenafil cohort trended toward having less of an improvement in VA coupling with dobutamine stress (p = 0.06). There were no differences between PVL measures of systolic or diastolic function between treatment groups, both at baseline and after dobutamine infusion. Patients with Fontan circulation had improved contractility and trended toward improvement in VA coupling with dobutamine stress. Acute sildenafil administration was not associated with improved PVL measurements of ventricular function in this population. These results suggest that clinical improvements seen with administration of sildenafil in Fontan patients are not associated with an acute improvement in ventricular function.
Single-ventricle heart disease; Pressure–volume loop; Sildenafil; Fontan
Annual surveillance coronary angiograpyhy to screen for graft coronary vasculopathy is routine practice after orthotopic heart transplantation. Traditionally, this is performed with direct coronary angiography using static single-plane or biplane angiography. Recently, technological advances have made it possible to perform dual-axis rotational coronary angiography (RA). This technique differs from standard static single-plane or biplane angiography in that a single detector is preprogrammed to swing through a complex 80° arc during a single injection. It has the advantage of providing a perspective of the vessels from a full arc of images rather than from one or two static images per contrast injection. The current study evaluated two coronary angiography techniques used consecutively at a single center to evaluate pediatric heart transplant recipients for graft coronary vasculopathy. A total of 23 patients underwent routine coronary angiography using both biplane static coronary angiography (BiP) and RA techniques at the Children's Hospital of Wisconsin from February 2009 to September 2010. Demographic and procedure data were collected from each procedure and analyzed for significance utilizing a Wilcoxon rank sum test. No significant demographic or procedural differences between the BiP and the RA procedures were noted. Specific measures of radiation dose including fluoroscopy time and dose area product were similar among the imaging techniques. The findings show that RA can be performed safely and reproducibly in pediatric heart transplant recipients. Compared with standard BiP, RA does not increase radiation exposure or contrast use and in our experience has provided superior angiographic imaging for the evaluation of graft coronary vasculopathy.
Coronary angiography; Graft vasculopathy; Heart transplantation
Maternal hypertension is common during pregnancy, and multiple studies have reported on an association between maternal hypertension and congenital heart defects (CHDs) in offspring; however, there is variability in the quality of these studies. A systematic review and meta-analysis was conducted on the associations between untreated and treated maternal hypertension and the risk of CHDs, evaluating CHDs overall as well as specific CHD subtypes. A systematic search of peer-reviewed articles published before August 2013 identified 16 studies evaluating the associations between untreated and treated maternal hypertension and CHDs. Summary relative risk (RR) estimates were calculated using fixed-effects models and random-effects models. Significant associations were observed between maternal hypertension and overall CHDs, for both treated [RR 2.0; 95 % confidence interval (CI) 1.5, 2.7] and untreated (RR 1.4; 95 % CI 1.2, 1.7) hypertension, as well as for overall hypertension regardless of treatment status (RR 1.8; 95 % CI 1.5, 2.2). The magnitude of effect was similar for the majority of CHD sub-types evaluated. The effects were also similar among women with hypertension who used one of multiple specific hypertension medications. There was no evidence of publication bias, and our results were robust to several factors considered in sensitivity analyses (e.g., source of exposure data, adjustment for potential confounders, and study design). Maternal hypertension was associated with CHDs. By understanding the specific mechanisms involved, appropriate strategies may be developed to reduce this risk, in order to prevent CHDs.
Hypertension; Pregnancy; Congenital heart defects; Meta-analysis
Magnesium sulfate was given to pediatric cardiac surgical patients during cardiopulmonary bypass period in an attempt to reduce the occurrence of postoperative junctional ectopic tachycardia (PO JET). We reviewed our data to evaluate the effect of magnesium on the occurrence of JET and assess a possible relationship between PO JET and procedure complexity. A total of 1088 congenital heart surgeries (CHS), performed from 2005 to 2010, were reviewed. A total of 750 cases did not receive magnesium, and 338 cases received magnesium (25 mg/kg). All procedures were classified according to Aristotle score from 1 to 4. Overall, there was a statistically significant decrease in PO JET occurrence between the two groups regardless of the Aristotle score, 15.3 % (115/750) in non-magnesium group versus 7.1 % (24/338) in magnesium group, P < 0.001. In the absence of magnesium, the risk of JET increased with increasing Aristotle score, P = 0.01. Following magnesium administration and controlling for body weight, surgical and aortic cross-clamp times in the analyses, reduction in adjusted risk of JET was significantly greater with increasing Aristotle level of complexity (JET in non-magnesium vs. magnesium group, Aristotle level 1: 9.8 vs. 14.3 %, level 4: 11.5 vs. 3.2 %; odds ratio 0.54, 95 % CI 0.31–0.94, P = 0.028). Our data confirmed that intra-operative usage of magnesium reduced the occurrence of PO JET in a larger number and more diverse group of CHS patients than has previously been reported. Further, our data suggest that magnesium’s effect on PO JET occurrence seemed more effective in CHS with higher levels of Aristotle complexity.
Magnesium; Ectopic junctional tachycardia; Congenital heart surgery; Postoperative arrhythmia
Annually, thousands of sudden deaths in individuals under 35 years remain unexplained following comprehensive medico-legal autopsy. Previously, post-mortem genetic analysis by Sanger-sequencing of 4 major cardiac channelopathy genes revealed that approximately one-fourth of these autopsy-negative sudden unexplained death in the young (SUDY) cases harbored an underlying mutation. However, there are now over 100 sudden death predisposing cardiac channelopathy-, cardiomyopathy-, and metabolic disorder-susceptibility genes. Here, we set out to determine whether post-mortem whole exome sequencing (WES) is an efficient strategy to detect ultra-rare, potentially pathogenic variants.
Materials and Methods
We performed post-mortem WES and gene-specific analysis of 117 sudden death-susceptibility genes for 14 consecutively-referred Caucasian SUDY victims (average age at death 17.4 ± 8.6 years) to identify putative SUDY-associated mutations.
On average, each SUDY case had 12,758 ± 2016 non-synonymous variants, of which 79 ± 15 localized to these 117 genes. Overall, 8 ultra-rare variants (7 missense, 1 in-frame insertion) absent in 3 publically available exome databases were identified in 6 genes (3 in TTN, and 1 each in CACNA1C, JPH2, MYH7, VCL, RYR2) in 7 of 14 cases (50%). Of the 7 missense alterations, 2 (T171M-CACNA1C, I22160T-TTN) were predicted damaging by 3 independent in-silico tools.
Although WES and gene-specific surveillance is an efficient means to detect rare genetic variants that might underlie the pathogenic cause of death, accurate interpretation of each variant is challenging. Great restraint and caution must be exercised less families be informed prematurely and incorrectly that the root cause has been found.
genes; long QT syndrome; cardiomyopathy; genetics; death; sudden
Background and Purpose
Preterm birth is associated with alteration in cortico-thalamic development, which underlies poor neurodevelopmental outcomes. Our hypothesis was that preterm neonates with CHD would demonstrate abnormal thalamic microstructure when compared to critically ill neonates without CHD. A secondary aim was to identify any association between thalamic microstructural abnormalities and peri-operative clinical variables.
Material and Methods
We compared thalamic DTI measurements in 21 preterm neonates with CHD to two cohorts of neonates without CHD: 28 term and 27 preterm neonates, identified from the same neonatal intensive care unit. Comparison was made with three other selected white matter regions using ROI manual based measurements. Correlation was made with post-conceptional age and peri-operative clinical variables.
In preterm neonates with CHD, there were age-related differences in thalamic diffusivity (axial and radial) compared to the preterm and term non-CHD group, in contrast to no differences in anisotropy. Contrary to our hypothesis, abnormal thalamic and optic radiation microstructure was most strongly associated with an elevated first arterial blood gas pO2 and elevated pre-operative arterial blood gas pH (p<0.05).
Age-related thalamic microstructural abnormalities were observed in preterm neonates with CHD. Perinatal hyperoxemia and increased peri-operative serum pH was associated with abnormal thalamic microstructure in preterm neonates with CHD. This study emphasizes the vulnerability of thalamo-cortical development in the preterm neonate with CHD.
Children with chronic diseases are at risk for low bone mineral density (BMD). There are no studies of BMD in children with congenital heart disease and particularly SV. Children with this defect are often treated with warfarin, suspected to negatively impact BMD in adults. We assessed BMD in patients with single ventricle (SV) physiology and compared the BMD of subjects taking warfarin to those who were not.
Subjects 5-12 years with SV were included. BMD z-scores by dual-energy X-ray absorptiometry (DXA) of the spine and total body less head (TBLH) were obtained. Calcium intake, activity level, height, and Tanner stage were assessed. Linear regression models and t-tests were used to investigate differences between participants and normative data as well as between subjects' subgroups.
Twenty six subjects were included; 16 took warfarin. Mean BMD z-score at the spine was significantly lower than expected at -1.0±0.2 (p<0.0001), as was the BMD z-score for TBLH at - 0.8±0.2 (p<0.0001). Those results remained significant after adjusting for height. Subjects who were on warfarin tended to have lower BMD at both the spine and TBLH than those who were not, with a z-score difference of 0.6±0.46 at the spine (p=0.106) and a difference of 0.4±0.34 at TBLH (p=0.132).
BMD is significantly reduced in children with SV. Warfarin appears to lower BMD but the effect is less conclusive. Continued evaluation is recommended for these patients at risk for reduced bone density. Evaluation of other cardiac patients on warfarin therapy should also be considered.
congenital heart disease/defects; bone mineral density; bone health; child health status; anticoagulation
Pulmonary insufficiency (PI) is associated with right ventricular (RV) dilation, dysfunction and exercise intolerance in patients with tetralogy of Fallot (TOF). We sought to compare RV function and exercise performance in patients with valvar pulmonary stenosis (VPS) following pulmonary balloon valvuloplasty to those with repaired TOF with similar degrees of PI.
We performed a cross-sectional study of patients with VPS and TOF. Cardiac magnetic resonance (CMR) and exercise stress test (EST) were performed. Subjects were matched by time from initial procedure and severity of PI using propensity scores.
After matching, there were 16 patients with VPS and 16 with TOF for comparison, with similar demographics. Time from initial procedure was 14 years (12; 16), p= 0.92, and pulmonary regurgitant fraction was 19 % (6; 31), p= 0.94, Patients with TOF had lower ejection fraction [58 % (53; 66) vs. 65 % [60; 69], p= 0.04] and more RV hypertrophy [69 g/m2 [52; 86] vs. 44 g/m2 [32; 66], p=0.04] compared to those with VPS. Aerobic capacity was worse in patients with TOF [68 ± 19% mVO2 (56; 84) vs. 82 ± 9.2 % (74; 89) in VPS, p=0.01], with a trend for less habitual physical activity [0.9 (0; 12) vs. 8 hours/ week (4; 12), p= 0.056], respectively.
With similar degrees of PI, patients with TOF demonstrate worse RV function and aerobic capacity as compared to patients with just VPS. Habitual exercise may in part explain differences in exercise performance and should be further explored.
Tetralogy of Fallot; Pulmonary stenosis; Outcome; Pulmonary insufficiency; Exercise; Congenital Heart Disease
Abstract After stage 1 palliation (S1P) with a Norwood operation, infants commonly experience growth failure during the initial interstage period. Growth failure during this high-risk period is associated with worse outcomes. This study evaluated the growth patterns of patients enrolled in the authors’ interstage home-monitoring program (HMP), which uses a multidisciplinary team approach to nutrition management. From 2000 to 2009, 148 infants were enrolled in the HMP after S1P. Families recorded daily weights during the interstage period and alerted the interstage monitoring team about protocol violations of nutritional goals. Interstage monitoring and inpatient data from the S1P hospitalization were reviewed to identify risk factors for poor growth. Growth outcomes were compared with published norms from the Centers for Disease Control. Interstage survival for patients in the HMP was 98 % (145/148). Growth velocity during the interstage period was 26 ± 8 g/day. The weight-for-age z-scores decreased from birth to discharge after S1P (−0.4 ± 0.9 to −1.3 ± 0.9; p < 0.001) but then increased during the interstage period to the time of S2P (−0.9 ± 1; p < 0.001). The factors associated with improved growth during the interstage period included male gender, greater birth weight, full oral feeding at S1P discharge, and a later birth era. After S1P, infants enrolled in an HMP experienced normal growth velocity during the interstage period. Daily observation of oxygen saturation, weight change, and enteral intake together with implementation of a multidisciplinary feeding protocol is associated with excellent interstage growth and survival.
Congenital; Growth; Heart defects; Home-monitoring program; Interstage growth; Norwood operation
Morbidity and mortality remain high for patients with hypoplastic left heart syndrome during the interstage period between Norwood and Glenn despite ongoing QI efforts. We sought to identify associations between the site of interstage care, interstage events, and mortality. Data for patients enrolled in the National Pediatric Cardiology Quality Improvement Collaborative (NPC-QIC) registry from July 2008 through February 2013 were reviewed. Patients had outpatient interstage care at (1) the surgical site (SS) performing Norwood, (2) a non-surgical site (NSS), or (3) a combination. Interstage events were compared among these groups and, when applicable, by distance from SS to NSS. 688 patients from 47 sites met entry criteria. Patients were followed at the SS 411 (60%), NSS 121 (17%), or a combination 143 (21%). Data was not available for 13 (2%). There were 66 deaths (10%) among the entire cohort: 37 (9%) at SS, 13 (11%) of at NSS, 15 (10%) at a combination. The proportion of deaths among these groups was not statistically significant (p=0.60), nor was there a difference based on SS to NSS distance. Patients followed at the SS were more likely to have problems detected with feeding (p=0.03) and breathing (p=0.002), and ED visits (p<0.001).
The site of interstage care was not associated with mortality, nor was the interstage care distance from the SS. Patients followed at the SS had more detected breathing and feeding problems, and ED visits. Further study is required to elucidate the clinical significance of these differences.
congenital heart disease; Hypoplastic left heart syndrome; Interstage; Quality Improvement
Perform a retrospective pilot study to evaluate the potential of myocardial T1 in assessment of Duchenne muscular dystrophy (DMD) cardiomyopathy.
Early identification of DMD cardiac disease, particularly myocardial fibrosis, would allow earlier therapy, potentially improving outcomes. Shortened myocardial T1 measured by cardiac MRI (CMR) is a measure of cardiac fibrosis that may be detected before late gadolinium enhancement (LGE). We hypothesized that the post-contrast T1 obtained from the Look-Locker sequences (T1LL), an easily obtainable surrogate of myocardial T1, would be abnormally shortened in DMD compared with controls.
T1LL measurement was performed on 21 DMD subjects and 11 controls; to account for individual variations in gadolinium distribution, myocardial T1LL was divided by blood pool T1LL, deriving T1LL ratios.
DMD subjects had shorter mean T1LL ratio than controls (1.42 vs 1.72, p<0.001). Subset analyses in DMD subjects with normal LVEF and without LGE also demonstrated significantly shorter T1LL ratio (−0.28, p<0.001 and −0.25, p=0.028).
Post-contrast T1LL ratio is abnormally shortened in DMD compared with controls, even in DMD patients with otherwise normal CMRs. The application of more aggressive therapy for those with shorter T1LL may favorably alter morbidity and improve mortality associated with DMD cardiomyopathy. These data suggest that further, prospective evaluation of myocardial T1 will be of benefit to patients with DMD.
Magnetic resonance imaging; Duchenne muscular dystrophy cardiomyopathy; Cardiomyopathy; T1 mapping; Myocardial fibrosis
M-mode and 2-dimensional (2D) echocardio-graphic imaging are routinely used to quantify left-ventricular (LV) size and function in pediatric patients with dilated cardiomyopathy (DCM). The reproducibility of and correlation between these techniques are unknown. This analysis sought to compare interreader, intrareader, and interacquisition reproducibility of M-mode versus 2D measurements in pediatric DCM patients. The Ventricular Volume Variability study of the Pediatric Heart Network is a multicenter, prospective, observational study assessing the course of chronic DCM in children. Two sonographers performed baseline image acquisitions locally, and two readers performed measurements at the echocardiographic core laboratory. One reader repeated measurements 1 month later. These data were used to assess reproducibility and agreement between M-mode and 2D measurements. One hundred sixty-nine subjects were enrolled. M-mode had similar or greater reproducibility in both intrareader and interreader settings for LV dimensions, shortening fraction (SF), and most wall thicknesses. In contrast, 2D reproducibility was similar or better for nearly all variables in the interacquisition setting but not for SF. Interacquisition variability was approximately twice the intrareader variability. LV dimensions by either modality consistently had high reproducibility and had the highest agreement between modalities. In pediatric DCM patients, variability of linear echocardiographic assessment could be minimized by relying on a single reader and using a consistent method (M-mode or 2D) for serial measurements, preferably M-mode when SF is the primary variable of interest. Except for LV dimensions, M-mode and 2D values should not be used interchangeably due to poor agreement.
Cardiomyopathy; Ventricular function; Pediatrics; Echocardiography; Reproducibility
To date limited data are available to predict the progression to end-stage heart failure (HF) with subsequent death (non-SCD), need for heart transplantation, or sudden cardiac death (SCD) in children with hypertrophic cardiomyopathy (HCM). We aimed to determine predictors of long-term outcome in children with HCM. A total of 112 children (median 14.1, IQR 7.8–16.6 years) were followed up for the median of 6.5 years for the development of morbidity and mortality, including arrhythmic and HF-related secondary end points. HF end point included HF-related death or heart transplant, and arrhythmic end point included resuscitated cardiac arrest, appropriate ICD discharge, or SCD. Overall, 23 (21 %) patients reached the pre-defined composite primary end point. At 10-year follow-up, the event-free survival rate was 76 %. Thirteen patients (12 %) reached the secondary arrhythmic end point, and 10 patients (9 %) reached the secondary HF end point. In multivariate model, prior cardiac arrest (r = 0.658), QTc dispersion (r = 0.262), and NSVT (r = 0.217) were independent predictors of the arrhythmic secondary end point, while HF (r = 0.440), LV posterior wall thickness (r = 0.258), LA size (r = 0.389), and decreased early transmitral flow velocity (r = 0.202) were all independent predictors of the secondary HF end point. There are differences in the risk factors for SCD and for HF-related death in childhood HCM. Only prior cardiac arrest, QTc dispersion, and NSVT predicted arrhythmic outcome in patients aged <18 years. LA size, LV posterior wall thickness, and decreased early transmitral flow velocity were strong independent predictors of HF-related events.
Hypertrophic cardiomyopathy; Sudden cardiac death; Cardioverter–defibrillator; Heart failure; Heart transplant; Children
In adults with heart failure, central sleep apnea (CSA), often manifested as Cheyne–Stokes respiration, is common, and has been associated with adverse outcome. Heart failure in children is commonly caused by dilated cardiomyopathy (DCM). It is unknown whether children with heart failure secondary to DCM have CSA, and whether CSA is related to the severity of heart failure. In this prospective observational study, 37 patients (<18 year) with heart failure secondary to DCM were included. They underwent polysomnography, clinical and laboratory evaluation and echocardiographic assessment. After a median follow-up time of 2 years, eight patients underwent heart transplantation. CSA (apnea–hypopnea index [AHI] ≥1) was found in 19 % of the patients. AHI ranged from 1.2 to 4.5/h. The occurrence of CSA was not related to the severity of heart failure. Three older patients showed a breathing pattern mimicking Cheyne–Stokes respiration, two of whom required heart transplantation. CSA was found in 19 % of the children with heart failure secondary to DCM. No relation was found with the severity of heart failure. In a small subset of children with severe DCM, a pattern mimicking Cheyne–Stokes respiration was registered.
Dilated cardiomyopathy; Pediatric; Polysomnography; Central sleep apnea
Deficient retro-aortic rim is of concern as a risk factor for aortic erosion following device closure of atrial septal defects (ASD). However, its prevalence and contribution to technical failure and adverse outcomes has not been delineated.
A single-center retrospective cohort study of children and adults undergoing cardiac catheterization for device occlusion of ASD from 1/1/1999 to 4/1/2012 was performed. Risk factors for technical failure and early adverse outcome were assessed using multivariate logistic regression.
Four-hundred forty-five consecutive subjects of median age 5.9 years (range: 0.8–80 years) underwent catheterization during the study period. Of subjects with reviewable echocardiograms, 60% had deficient retro-aortic rim. No attempt was made at device closure in 3.6% of subjects. Of the remaining 429 subjects, 96% underwent successful device occlusion. Major early adverse events occurred in 1.2% (95% CI: 0.4–2.7%) of cases, all either device embolization or malposition. Deficient retro-aortic rim was not a risk factor for composite outcome of technical failure or early major adverse event. No deaths, late re-interventions, or erosion events occurred over 2,395 total person-years of follow-up (median 5.8 years). Deficient retro-aortic rim was associated with increased risk of device impingement on the aorta, but no association was seen between device impingement or deficient retro-aortic rim and the development of new/progressive aortic insufficiency.
Deficient retro-aortic rim is highly prevalent but did not increase risk of adverse outcomes. Its contribution to the risk of aortic erosion could not be addressed by this study.
septal occluder device; PEDS–pediatric interventions; heart defects; congenital; cardiac catheterization
Chylothorax is a rare but serious complication in children who undergo heart surgery. Its pathogenesis is poorly understood, and invasive surgical treatments are considered only after conservative management fails. Current diagnostic imaging techniques, which could aid decision making for earlier surgical intervention, are difficult to apply. Herein, we deployed near-infrared fluorescence (NIRF) lymphatic imaging to allow the visualization of abnormal lymphatic drainage in an infant with postoperative chylothorax to guide the choice of surgical management.
A 5-week-old male infant, who developed chylothoraces after undergoing Norwood surgery for hypoplastic left heart syndrome, was intradermally administered trace doses of indocyanine green in both feet and the left hand. NIRF imaging was then performed at the bedside to visualize lymphatic drainage patterns.
Imaging results indicated impeded lymphatic drainage from the feet toward the trunk with no fluorescence in the chest indicating no leakage of peripheral lymph at the thoracic duct. Instead, lymph drainage occurred from the axilla directly into the pleural cavity. As a result of imaging, left pleurodesis was performed to stop the pleural effusion with the result of temporary decrease of left chest tube drainage.
Although additional studies are required to understand normal and abnormal lymphatic drainage patterns in infants, we showed the potential of using NIRF lymphatic imaging at the bedside to visualize the lymphatic drainage pathway to guide therapy. Timely management of chylothorax may be improved by using NIRF imaging to understand lymphatic drainage pathways.
Near-infrared fluorescence imaging; Chylothorax; Congenital heart defect; Postoperative care
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.
TAPSE; Right ventricle; Hypoplastic left heart syndrome; Fontan; Cardiac magnetic resonance; Echocardiography
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 in4 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.
Hypoplastic left heart syndrome; Atrial septal defect; Aortic atresia
The surgical management of transposition complex with aortic arch obstruction remains technically demanding due to anatomic complexity. Even in the recent surgical era, there are centers that address this anomaly with a staged strategy. This report presents our experiences with a one-stage repair of transposition complexes with aortic arch obstructions more than the last 10 years. Since 2003, 19 patients with a transposition of the great arteries (TGA, 2 patients) or a double outlet of the right ventricle (DORV, 17 patients) and aortic arch obstruction have undergone one-stage repair of their anomalies. The mean age was 6.7 ± 2.3 days, and the mean body weight was 3.4 ± 0.3 kg. The 2 patients with TGA exhibited coarctation of the aorta. The 17 patients with DORV all exhibited the Taussig–Bing type. The great artery relationships were anteroposterior in 4 patients (21.1 %). The coronary artery anatomies were usual (1LCx; 2R) in 8 patients (42.1 %). There were 2 early deaths (10.5 %). Seven patients (36.8 %) required percutaneous interventions. One patient required re-operation for pulmonary valvar stenosis and left pulmonary artery patch angioplasty. The overall survival was 84.2 %. The freedom from mortality was 83.5 % at 5 years, and the freedom from intervention was 54.4 % at 5 years. The one-stage repair of transposition complexes with aortic arch obstructions resulted in an acceptable survival rate and a relatively high incidence of postoperative catheter interventions. Postoperative catheter interventions are highly effective. Transposition complexes combined with aortic arch obstructions can be managed by one-stage repair with good early and midterm results.
Transposition of the great vessels; Double outlet right ventricle; Aortic coarctation; Interruption of aortic arch
There is no clear consensus on optimal management of fetuses affected by familial hypertrophic cardiomyopathy (HCM). Intrauterine treatment of the condition has not been attempted in any standardized fashion. We report the case of a fetus treated by maternal propranolol during the third trimester after septal hypertrophy and diastolic dysfunction was diagnosed on fetal echocardiogram. The pregnancy went successfully to term, and fetal septal hypertrophy was noted to improve prior to delivery.
Fetal hypertrophic cardiomyopathy; Beta myosin mutation; Propranolol; Fetal echocardiography
Congenital atrioventricular (AV) block is commonly associated with heterotaxy syndrome; together they have reportedly low survival rates (10–25 %). However, information about perinatal outcome and predictors of nonsurvival after prenatal diagnosis of this association is scarce. Therefore, we studied fetuses with heterotaxy syndrome and bradycardia or AV-block diagnosed between 1995 and 2011, and analyzed pre and post-natal variables. The primary outcome was death and the secondary outcome was pacemaker placement. Of the 154 fetuses with heterotaxy syndrome, 91 had polysplenia syndrome, 22/91(24 %) with bradycardia or AV-block. Thirteen (59 %) patients had sinus bradycardia at diagnosis, 8 (36 %) complete AV block, and 1 (5 %) second-degree AV-block. Three patients elected for termination of pregnancy (3/22, 14 %), 4 had spontaneous fetal demise (4/22, 18 %), and 15 (15/22, 68 %) were live-born. Of the fetuses with bradycardia/AV-block, 30 % presented with hydrops, 20 % had ventricular rates <55 beats/min, and 10 % had cardiac dysfunction. Excluding termination of pregnancy, 15/19 fetuses (79 %) survived to birth. Among the 15 live-born patients, 4 had bradycardia and 11 had AV-block. A further 3 patients died in infancy, all with AV-block who required pacemakers in the neonatal period. Thus, the 1-year survival rate, excluding termination of pregnancy, was 63 % (12/19). Of the remaining 12 patients, 9 required pacemaker. Predictors of perinatal death included hydrops (p < 0.0001), ventricular dysfunction (p = 0.002), prematurity (p = 0.04), and low ventricular rates (p = 0.04). In conclusion, we found a higher survival rate (63 %) than previously published in patients with heterotaxy syndrome and AV block or bradycardia diagnosed prenatally. Hydrops, cardiac dysfunction, prematurity and low ventricular rates were predictors of death.
Prenatal diagnosis; Heterotaxy syndrome; Atrioventricular block; Bradycardia
Infants with critical congenital heart disease, especially patients with a single-ventricle (SV) physiology, are at increased risk for the development of necrotizing enterocolitis (NEC). Decreased splanchnic oxygen delivery may contribute to the development of NEC and may be detected by regional oximetry (rSO2) via splanchnic near-infrared spectroscopy (NIRS). This prospective study enrolled 64 neonates undergoing biventricular (BV) repair or SV palliation for CHD and monitored postoperative splanchnic rSO2 before and during initiation of enteral feedings to determine whether changes in rSO2 are associated with risk of NEC. Suspected or proven NEC was observed in 32 % (11/34) of the SV subjects and 0 % (0/30) of the BV subjects (p = 0.001). Compared with the BV subjects, the SV palliated subjects had significantly lower splanchnic rSO2 before and during initiation of enteral feedings, but the groups showed no difference after correction for lower pulse oximetry (SpO2) in the SV group. The clinical parameters were similar among the SV subjects with and without NEC except for cardiopulmonary bypass times, which were longer for the patients who experienced NEC (126 vs 85 min; p = 0.03). No difference was observed in splanchnic rSO2 or in the SpO2–rSO2 difference between the SV subjects with and without NEC. Compared with the patients who had suspected or no NEC, the subjects with proven NEC had a lower average splanchnic rSO2 (32.6 vs 47.0 %; p = 0.05), more time with rSO2 less than 30 % (48.8 vs 6.7 %; p = 0.04) at one-fourth-volume feeds, and more time with SpO2–rSO2 exceeding 50 % (33.3 vs 0 %; p = 0.03) before feeds were initiated. These data suggest that splanchnic NIRS may be a useful tool for assessing risk of NEC, especially in patients with an SV physiology.
Necrotizing enterocolitis; Congenital heart; Regional oximetry; NIRS; Splanchnic ischemia; Mesenteric ischemia
Echocardiographic measurements of diastolic function have not been validated against invasive pressure-volume loop (PVL) analysis in the single ventricle population. We hypothesized that echocardiographic measures of diastolic function would correlate with PVL indices of diastolic function in patients with single ventricle physiology.
Materials and Methods
Conductance-derived PVL measures of diastolic function included the isovolumic relaxation time constant (tau), maximum rate of ventricular pressure decline (peak -dP/dt), and a measure of passive diastolic stiffness, μ. 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 TDI-derived isovolumic relaxation time (IVRT′). The correlation between PVL and echocardiographic measures was examined.
Thirteen patients were enrolled at various stages of surgical palliation. Median age was 3yr (range 3mo to 19yr). Tau 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). There was also correlation between peak -dP/dt and IVRT′ (r = 0.609, p = 0.036) while μ also 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. We found that Doppler E:A, lateral E:E′, and IVRT′ correlate well with PVL measures of diastolic function. This study supports the further validation of echocardiographic measures of diastolic function vs. PVL measures of diastolic function in the single ventricle population..
Pressure-volume loop; single ventricle; echocardiography; diastolic function