Background Anomalous aortic origin of a coronary artery from the opposite sinus with an intramural course between the great arteries (AAOCA) is associated with ischemia and sudden cardiac death in ...children, and surgical unroofing has been used to alleviate that risk. Methods The cardiology database was reviewed to identify all patients with AAOCA who underwent surgical unroofing 10 years. Results From March 1999 to September 2009, 27 patients with a mean age of 12.6 ± 3.5 years (range, 4–20 years) had surgical unroofing of AAOCA of the left coronary from the right sinus (left AAOCA, 7/27, 26%) or of the right coronary from the left sinus (right AAOCA, 20/27, 74%). Of these, 26 had diagnoses made by transthoracic echocardiography. Symptoms included resuscitated sudden cardiac death in 3, syncope in 8, and chest pain in 4. No symptoms were present in 12 cases of serendipitous diagnosis. Unroofing of the intramural portion was successfully performed in all cases. A slitlike coronary orifice was described at surgical inspection in 12 patients, 7 of whom had right AAOCA and no symptoms. All patients after unroofing have patent coronary flow by Doppler and normal echocardiography and exercise treadmill testing at mean follow-up of 1.8 years. None have activity restrictions. Conclusions AAOCA is frequently characterized by an intramural course, which can be reliably identified by echocardiography. This form can be safely repaired by unroofing the intramural segment without early morbidity. Symptoms of possible ischemia are common but not always correlated with coronary ostial findings at surgery.
The Single Ventricle Reconstruction trial demonstrated a transplantation-free survival advantage at 12-month follow-up for patients with right ventricle-pulmonary artery shunts (RVPAS) with the ...Norwood procedure compared with modified Blalock-Taussig shunts but similar survival and decreased global right ventricular (RV) function on longer term follow-up. The impact of the required ventriculotomy for the RVPAS remains unknown. The aim of this study was to compare echocardiography-derived RV deformation indices after stage 2 procedures in survivors with single RV anomalies enrolled in the Single Ventricle Reconstruction trial.
Global and regional RV systolic longitudinal and circumferential strain and strain rate, ejection fraction, and short-axis percentage fractional area change were all derived by speckle-tracking echocardiography from protocol echocardiograms obtained at 14.3 ± 1.2 months. Student t tests or Wilcoxon rank sum tests were used to compare groups.
The cohort included 275 subjects (129 in the modified Blalock-Taussig shunt group and 146 in the RVPAS group). Longitudinal deformation could be quantified in 214 subjects (78%) and circumferential measures in 182 subjects (66%). RV ejection fraction and percentage fractional area change did not differ between groups. There were no significant differences between groups for global or regional longitudinal deformation. Circumferential indices showed abnormalities in deformation in the RVPAS group, with decreased global circumferential strain (P = .05), strain rate (P = .09), and anterior regional strain rate (P = .07) that approached statistical significance.
RV myocardial deformation at 14 months, after stage 2 procedures, was not significantly altered by the type of initial shunt placed. However, abnormal trends were appreciated in circumferential deformation for the RVPAS group in the area of ventriculotomy that may represent early myocardial dysfunction. These data provide a basis for longer term RV deformation assessment in survivors after Norwood procedures.
Objective The study objective was to identify factors associated with death and cardiac transplantation in infants undergoing the Norwood procedure and to determine differences in associations that ...might favor the modified Blalock–Taussig shunt or a right ventricle-to-pulmonary artery shunt. Methods We used competing risks methodology to analyze death without transplantation, cardiac transplantation, and survival without transplantation. Parametric time-to-event modeling and bootstrapping were used to identify independent predictors. Results Data from 549 subjects (follow-up, 2.7 ± 0.9 years) were analyzed. Mortality risk was characterized by early and constant phases; transplant was characterized by only a constant phase. Early phase factors associated with death included lower socioeconomic status ( P = .01), obstructed pulmonary venous return ( P < .001), smaller ascending aorta ( P = .02), and anatomic subtype. Constant phase factors associated with death included genetic syndrome ( P < .001) and lower gestational age ( P < .001). The right ventricle-to-pulmonary artery shunt demonstrated better survival in the 51% of subjects who were full term with aortic atresia ( P < .001). The modified Blalock–Taussig shunt was better among the 4% of subjects who were preterm with a patent aortic valve ( P = .003). Lower pre-Norwood right ventricular fractional area change, pre-Norwood surgery, and anatomy other than hypoplastic left heart syndrome were independently associated with transplantation (all P < .03), but shunt type was not ( P = .43). Conclusions Independent risk factors for intermediate-term mortality include lower socioeconomic status, anatomy, genetic syndrome, and lower gestational age. Term infants with aortic atresia benefited from a right ventricle-to-pulmonary artery shunt, and preterm infants with a patent aortic valve benefited from a modified Blalock–Taussig shunt. Right ventricular function and anatomy, but not shunt type, were associated with transplantation.
After the arterial switch operation (ASO) for transposition of the great arteries (TGA), the native pulmonary root and valve function in the systemic position, and the long-term risk for neoaortic ...root dilation and valve regurgitation is currently undefined. The aim of this study was to determine the prevalence and progression of neoaortic root dilation and neoaortic valve regurgitation in patients with TGA repaired with the ASO.
Measurements of the neoaortic annulus, neoaortic root at the level of the sinuses of Valsalva, and the degree of neoaortic regurgitation were assessed by serial transthoracic echocardiograms on 124 patients with TGA at a median follow-up of 7.2 years (range, 1 to 23 years) after the ASO at our institution.
Neoaortic root dilation with z scores of 2.5 or greater was identified in 66%, and the root diameter z score increased at an average rate of 0.08 per year over time after ASO. Freedom from neoaortic root dilation at 1, 5, 10, and 15 years after ASO was 84%, 67%, 47%, and 32%, respectively. Risk factors for root dilation include history of double-outlet right ventricle (p = 0.003), previous pulmonary artery banding (p = 0.01), and length of follow-up (p = 0.04). Neoaortic valve regurgitation of at least moderate degree was present in 14%. Neoaortic root dilation was a significant risk factor for neoaortic valve regurgitation (p < 0.0001). No patient required reintervention on the neoaorta or neoaortic valve during follow-up.
Progressive neoaortic root dilation is common in patients with TGA after the ASO. Continued surveillance of this population is required.
Abstract Background In children with single right ventricular (RV) anomalies, changes in RV size and function may be influenced by shunt type chosen at the time of the Norwood procedure. Objectives ...The study sought to identify shunt-related differences in echocardiographic findings at 14 months and ≤6 months pre-Fontan in survivors of the Norwood procedure. Methods We compared 2-dimensional and Doppler echocardiographic indices of RV size and function, neo-aortic and tricuspid valve annulus dimensions and function, and aortic size and patency at 14.1 ± 1.2 months and 33.6 ± 9.6 months in subjects randomized to a Norwood procedure using either the modified Blalock-Taussig shunt (MBTS) or right ventricle to pulmonary artery shunt (RVPAS). Results Acceptable echocardiograms were available at both time points in 240 subjects (114 MBTS, 126 RVPAS). At 14 months, all indices were similar between shunt groups. From the 14-month to pre-Fontan echocardiogram, the MBTS group had stable indexed RV volumes and ejection fraction, while the RVPAS group had increased RV end-systolic volume (p = 0.004) and decreased right ventricular ejection fraction (RVEF) (p = 0.004). From 14 months to pre-Fontan, the treatment groups were similar with respect to decline in indexed neo-aortic valve area, >mild neo-aortic valve regurgitation (<5% at each time), indexed tricuspid valve area, and ≥moderate tricuspid valve regurgitation (<20% at each time). Conclusions Initial Norwood shunt type influences pre-Fontan RV remodeling during the second and third years of life in survivors with single RV anomalies, with greater RVEF deterioration after RVPAS. Encouragingly, other indices of RV function remain stable before Fontan regardless of shunt type. (Comparison of Two Types of Shunts in Infants with Single Ventricle Defect Undergoing Staged Reconstruction—Pediatric Heart Network; NCT00115934 )
Objective The initial palliative procedure for patients born with hypoplastic left heart syndrome and related single right ventricle anomalies, the Norwood procedure, remains among the highest risk ...procedures in congenital heart surgery. The classic Norwood procedure provides pulmonary blood flow with a modified Blalock–Taussig shunt. Improved outcomes have been reported in a few small, nonrandomized studies of a modification of the Norwood procedure that uses a right ventricle–pulmonary artery shunt to provide pulmonary blood flow. Other nonrandomized studies have shown no differences between the two techniques. Methods The Pediatric Heart Network designed a randomized clinical trial to compare outcomes for subjects undergoing a Norwood procedure with either the right ventricle–pulmonary artery or modified Blalock–Taussig shunt. Infants with a diagnosis of single, morphologically right ventricle anomaly who are undergoing a Norwood procedure are eligible for inclusion in this study. The primary outcome is death or cardiac transplant 12 months after random assignment. Secondary outcomes include postoperative morbidity after Norwood and stage II palliation procedures, right ventricular function and pulmonary arterial growth at stage II palliation, and neurodevelopmental outcomes at 14 months old. Incidence of adverse events will also be compared between treatment groups. Conclusion This study will make an important contribution to the care of patients with hypoplastic left heart syndrome and related forms of single, morphologically right ventricle. It also establishes a model with which other operative interventions for patients with congenital cardiovascular malformations can be evaluated in the future.
Chloral hydrate has been the drug of choice for uncooperative infants and children requiring sedation for echocardiography. Recently, the commercially available liquid formulation was discontinued by ...the manufacturer, and the only oral form of chloral hydrate available was made using reconstituted crystals. The aim of this study was to compare sedation efficacy before and after this change in chloral hydrate formulas.
Consecutive patients presenting for echocardiography sedation during the transition from the manufacturer-derived old formulation to the locally reconstituted new formulation were retrospectively reviewed for time to onset of level 3 sedation, duration of level ≤3 sedation, requirement for additional sedative medications, sedation failure, ability to complete the echocardiographic examination, and adverse events related to the sedatives.
The cohort included 124 patients (63 old, 61 new). Although the mean age at sedation was younger for the new group, the weight and average dose of chloral hydrate used were not significantly different. There were no adverse events in either group. Time to onset of sedation was the same between the two formulations, but the duration of sedation was significantly shorter for the new group (42.4 ± 24.5 vs 55.3 ± 26.2 min, P = .01). In addition, the need for secondary sedating agents because of inadequate sedation and sedation failure were significantly greater using the new compared with the old formulation.
Chloral hydrate reformulation using reconstituted crystals results in a shorter duration of sedation, more frequent requirement for a secondary sedative agent, more frequent sedation failure, and occasional inability to complete the echocardiographic examination compared with the manufacturer's formulation.
A Pediatric Heart Network trial compared outcomes in infants with single right ventricle anomalies undergoing Norwood procedures randomized to modified Blalock-Taussig shunt (MBTS) or right ...ventricle-to-pulmonary artery shunt (RVPAS). Doppler patterns in the neo-aorta and RVPAS may characterize physiologic changes after staged palliations that affect outcomes and right ventricular (RV) function.
Neo-aortic cardiac index (CI), retrograde fraction (RF) in the descending aorta and RVPAS conduit, RVPAS/neo-aortic systolic ejection time ratio, and systolic/diastolic (S/D) ratio were measured early after Norwood, before stage II palliation, and at 14 months. These parameters were compared with transplantation-free survival, length of hospital stay, and RV functional indices.
In 529 subjects (mean follow-up period, 3.0 ± 2.1 years), neo-aortic CI and descending aortic RF were significantly higher in the MBTS cohort after Norwood. The RVPAS RF averaged <25% at both interstage intervals. Higher pre-stage II descending aortic RF was correlated with lower RV ejection fraction (R = -0.24; P = .032) at 14 months for the MBTS cohort. Higher post-Norwood CI (5.6 vs 4.4 L/min/m(2), P = .04) and lower S/D ratio (1.40 vs 1.68, P = .01) were correlated with better interstage transplantation-free survival for the RVPAS cohort. No other Doppler flow patterns were correlated with outcomes.
After the Norwood procedure, infants tolerated significant descending aortic RF (MBTS) and conduit RF (RVPAS), with little correlation with clinical outcomes or RV function. Neo-aortic CI, ejection time, and S/D ratios also had limited correlations with outcomes or RV function, but higher post-Norwood neo-aortic CI and lower S/D ratio were correlated with better interstage survival in those with RVPAS.
The study objective was to compare echocardiographic indices in infants with hypoplastic left heart syndrome (HLHS) randomized to different surgical pathways.
Initial surgical palliation for HLHS has ...evolved to two strategies that vary by source of pulmonary blood flow: a modified Blalock-Taussig (BT) shunt or a right ventricle to pulmonary artery (RV-PA) conduit.
Seventeen patients were randomized to either a BT shunt or RV-PA as their first-stage palliation, and 15 survived through bidirectional Glenn (BDG) (seven BT shunts/eight RV-PAs). Echocardiography was performed pre-stage 1 palliation (S1P), early post-S1P, pre-BDG, and post-BDG. Echocardiographic measurements included indices of right ventricle function and shape, right ventricle myocardial performance index, neoaortic Doppler flow patterns and cardiac output, Doppler inflow and tissue imaging, and conduit/neoaortic regurgitant fraction.
There were no significant differences in right ventricle size, shape, or estimates of systolic and diastolic function between groups. Patterns of changes in neoaortic Doppler flow in the RV-PA conduit group showed a decrease in all indices of systemic flow early after initial palliation, but these measures consistently increase later post-S1P and post-BDG. In contrast, the BT shunt group increases these same indices post-S1P and pre-BDG with a decrease after shunt removal.
Right ventricle size and function do not appear significantly affected by surgical type of initial palliation for HLHS, and this correlates with early outcome. Echocardiographic Doppler findings correlate well with the expected physiologies of the different shunts as these infants progress through initial palliative strategies.
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