Effects of Pulmonary Regurgitation on Distensibility and Flow of the Branch Pulmonary Arteries in Tetralogy of Fallot

Significant pulmonary regurgitation (PR) after repair of tetralogy of Fallot (TOF) may affect flow in the pulmonary artery (PA) side branches. We sought to assess flow changes and distensibility of the PA side branches in vivo and test correlation with the degree of PR and right-ventricular (RV) dilatation. Thirty patients after TOF repair and 16 controls underwent cardiovascular magnetic resonance for quantification of RV volumes and measurement of flow in the PA side branches. RV volumes and function, blood flow volumes, and cross-sectional area of the main, left (LPA), and right (RPA) PA were measured and regurgitant volumes and distensibility calculated. Results were compared between the LPA and the RPA and between patients and controls. Median regurgitation fraction of PR was 41 % (range 22–60 %). Regurgitant fraction was greater in the LPA (40 %) than in the RPA (29 %), resulting in lower net flow into the LPA (p < 0.001). LPA area was significantly greater than that of the RPA (303.9 vs. 232.7 mm²/m²) (p < 0.0001). The LPA showed lower distensibility than the RPA (39 vs. 44 %). PA side branch distensibility correlated with MPA regurgitant volume (p = 0.001), MPA regurgitant fraction (p = 0.001), and RV end-diastolic volume (p = 0.03). PA side branches have greater distensibility in patients with PR than in normal subjects. Significant PR leads to changes in flow profile and distensibility of the PA side branches. The LPA shows greater regurgitant volume and greater area but lower distensibility than the RPA.     

Stenting Right Ventricular Outflow in an Infant With Tetralogy of Fallot and Well-Developed Pulmonary Arteries

A right ventricular outflow tract stent was implanted in a 1-month-old (3.5 kg) baby boy with tetralogy of Fallot and worsening cyanosis to relieve infundibular and pulmonary valve stenosis in the setting of well-developed pulmonary artery branches. This management allowed a symmetric and optimal growth of the pulmonary artery branches, with right and left pulmonary arteries measuring 7-mm (z-score, +1.3 SD) and 7.3-mm (z-score, +1.7 SD), respectively, 3 months after stent implantation. No signs of pulmonary overcirculation developed, and complete surgical repair was performed at the age of 6 months.     

Valve-Sparing Tetralogy of Fallot Repair With Intraoperative Dilation of the Pulmonary Valve

Deleterious long-term effects of pulmonary regurgitation after tetralogy of Fallot (TOF) repair have become evident during the last two decades. Subsequently, different groups have developed strategies aimed at preserving the pulmonary valve function. However, the results of these approaches are not well known. From July 2009 through March 2012, 38 patients underwent primary repair of TOF at the authors’ institution. Of these, 12 children (7 boys) underwent attempted pulmonary valve-sparing surgery with intraoperative dilation of the pulmonary valve. The technical details as well as the echocardiographic preoperative and follow-up data for this repair were recorded, with a special focus on the feasibility of the technique and the effects on pulmonary valve function. No patient in the series died. At repair, the median age was 6 months (range 3.4–126 months), and the median weight was 7.6 kg (range 4.7–47 kg). Intraoperative dilation of the pulmonary valve was technically feasible for all the patients. Two patients had unsuccessful dilation and underwent a transannular patch procedure. During a median follow-up period of 22 months (range 6–30 months), the pulmonary valve diameter and z-score improved significantly. Moreover, the annular size normalized, whereas the mean right ventricular outflow tract (RVOT) gradient remained at the mild level (median, 24 mmHg; range 12–36 mmHg). At the most recent follow-up evaluation, three patients showed moderate pulmonary regurgitation. Intraoperative dilation of the pulmonary valve in patients undergoing TOF repair is feasible and provides good relief of obstruction. Moreover, the pulmonary valve annulus grows through the follow-up period. Longer follow-up studies are needed to evaluate the exact role of this strategy in this population.     

Dimensions of the Ascending Aorta in Conotruncal Heart Defects

Dilatation of the ascending aorta is an important sequel in conotruncal anomalies, such as tetralogy of Fallot (TOF) or d-transposition of the great arteries (TGA). We measured dimensions and their progression at different levels of the ascending aorta in 80 patients. In TOF patients, mean z-score for aortic annulus was 1.65 (range ?3.16–6.47), for sinus 1.93 (range ?2.28–5.39), for st-junction 4.15 (range 0.0–8.18), and for ascending aorta 3.51 (range ?1.23–6.36). Over time, annulus z-scores increased in the univariate analysis [0.07/year, 95 % confidence interval (CI) 0.01–0.14; p = 0.02], and this was unique to male patients (0.08/year, 95 % CI 0.00–0.15; p = 0.05). z-scores of the ascending aorta decreased (?0.1/year, 95 % CI ?0.18 to ?0.02; p = 0.02), and this was confined to patients without aortic regurgitation (AR; ?0.09/year, 95 % CI ?0.18 to ?0.01; p = 0.04). In TGA, mean z-score for the aortic annulus was 2.13 (range ?3.71–8.39), for sinus 1.77 (range ?3.04–6.69), for st-junction 1.01 (range ?5.44–6.71), and for ascending aorta 0.82 (range ?4.91–6.46). In bivariate analysis, annulus z-scores decreased in females (?0.14/year, 95 % CI ?0.25 to ?0.03; p = 0.01) and in patients without AR (?0.07/year, 95 % CI ?0.14–0.0; p = 0.03). z-scores of the ascending aorta increased significantly in males (0.08/year, 95 % CI 0.0 to 0.16; p = 0.05) and in patients with AR (0.12/year, 95 % CI 0.03–0.21; p = 0.01). In conclusion, TOF and TGA z-scores of the ascending aorta differ significantly from those of the normal population. Progression of z-scores over time is influenced by diagnosis, sex, and presence of AR.     

Fetal Echocardiographic Measurements and the Need for Neonatal Surgical Intervention in Tetralogy of Fallot

Background

This study aimed to evaluate fetal echocardiographic measurements at the time of the first fetal echocardiogram as predictors of neonatal outcome for tetralogy of Fallot (TOF).

Methods

The study reviewed all infants with a prenatal diagnosis of TOF from January 2004 to June 2011. Aortic valve (AoV), pulmonary valve (PV), main pulmonary artery (MPA), left and right pulmonary artery diameters, and ductus arteriosus flow were evaluated on fetal echocardiograms, and associations between the fetal echocardiogram and the neonatal echocardiogram measurements and outcomes were assessed.

Results

The study identified 67 TOF patients who had an initial fetal echocardiogram at a mean gestational age of 25.0 ± 5.2 weeks. Patients with absent PV syndrome or major aortopulmonary collaterals were excluded from the study, as were those without anterograde pulmonary blood flow at the first fetal echocardiogram. Of the remaining 44 patients, 10 were ductal dependent and required neonatal surgery. Infants who were ductal dependent had lower fetal PV (?5.38 ± 2.95 vs. ?3.51 ± 1.66; p < 0.05) and MPA (?3.94 ± 1.66 vs. ?2.87 ± 1.04; p < 0.05) z-scores. A fetal PV z-score of ?5 predicted ductal dependence with 78 % sensitivity and 87 % specificity, and a PV z-score of ?3 showed 100 % sensitivity and 34 % specificity (p < 0.001). Fetuses with a reversed left-to-right flow across the ductus arteriosus (DA) were more likely to be ductal dependent (odds ratio, 25; p < 0.001) than those who had normal ductal flow.

Conclusions

In TOF, fetal PV and MPA z-scores and direction of the DA blood flow predict neonatal ductal dependence. Patients with fetal PV z-scores lower than ?3 or any left-to-right flow at the level of the DA should be admitted to a center where prostaglandin is available.     

Tetralogy of Fallot With Atrioventricular Septal Defect: Surgical Strategies for Repair and Midterm Outcome of Pulmonary Valve-Sparing Approach

Repair for tetralogy of Fallot (TOF) with complete atrioventricular septal defect (CAVSD) has been reported with good early and intermediate outcomes. Morbidity, however, remains significantly high. To date, repair of CAVSD/TOF using a pulmonary valve-sparing technique (PVS) and freedom from valve reoperation are not well defined. A study was undertaken to investigate outcomes. This study was conducted in as a retrospective investigation. Between January 1988 and December 2008, 13 consecutive patients with CAVSD/TOF were identified, and their records were reviewed retrospectively. Of these 13 patients, 9 had Rastelli type C CAVSD. Trisomy 21 was present in 9 cases (69 %; 7 with type C). Five patients had received a systemic-to-pulmonary shunt (SPS) before complete repair at a mean age 1.7 ± 0.6 months. All the patients survived until complete repair. At complete CAVSD/TOF repair, AVSD was corrected with a two-patch technique in all patients. For eight patients (61.5 %), PVS was used. The remaining five patients had transannular patch (TAP) repair. The mean age at complete repair was 6.3 ± 2.4 months. At complete repair, the mean cardiopulmonary bypass time was 173.5 ± 30.6 min, and the cross-clamp time was 134.7 ± 28.8 min. There was one hospitalization and no late deaths. The median follow-up period was 9.2 years [interquartile range (IQR), 4.7–13.3 years]. The actuarial survival was 90.0 ± 9.5 % at 1 year, 90 ± 9.5 % at 5 years, and 90 ± 9.5 % at 8 years. Of the 12 survivors, 6 had some reintervention during the follow-up period. Within the first 11 years after complete repair, two patients underwent left atrioventricular (AV) valve repair, and one patient had right AV valve repair. Two patients had residual VSD closure. Four patients underwent the first right ventricular outflow tract (RVOT) reintervention for critical insufficiency or stenosis at a mean interval of 6 ± 21) months. One patient had a second RVOT reoperation. Findings showed that CAVSD/TOF with PVS was related to significantly higher freedom from RVOT reintervention (100 % at 1, 5, and 8 years compared with 80 ± 17.9 % at 1 year, 60 ± 21.9 % at 5 years, and 40 ± 21.9 % at 8 years for CAVSD/TOF using TAP; P < 0.05). No patient who underwent PVS had left ventricular outflow tract obstruction requiring reoperation. Overall freedom from any reintervention was 90.9 ± 8.6 % at 1 year, 71.6 ± 14.0 % at 5 years, and 53.7 ± 8.7 % at 8 years in this group of patients. Correction of TOF with CAVSD can be performed at low risk with favorable intermediate-term survival and satisfactory freedom from reoperation. Use of TAP can be avoided in almost two thirds of patients and may influence freedom from early RVOT reintervention.     

The Impact of Aortic Valve Replacement on Left Ventricular Remodeling in Children

There are scant data in pediatrics on the optimal timing for aortic valve repair (AVR). This study assesses the midterm response to AVR and possible predictors of poor outcome. From 2001 to 2006, 41 patients had greater than 3-month follow-up after AVR for aortic insufficiency, aortic stenosis, or both. Pre-, peri-, and post-operative data were collected, including demographics and clinical symptoms. Two reviewers measured echocardiographic parameters from the pre-operative and latest follow-up echocardiograms. Ventricular dimensions were indexed to body surface area (z-score). Median age at AVR was 13 years with 83 % having a Ross operation. The average left ventricular end-diastolic dimension pre-op, z-score of +1.3, significantly decreased at last follow-up to a mean z-score of ?0.1 (p < 0.001). Similarly the indexed LV mass decreased from +3.9 to +0.5 (p < 0.001). There was no significant correlation between the presence of pre-op symptoms and the presence of post-op LV dilatation, hypertrophy, or dysfunction. In the subset of patients (7/41) with persistent LV dysfunction at last follow-up, there was a significant correlation with pre-op LV dilatation as assessed by both LVEDD (p = 0.02) and LVESD (p = 0.05). Children demonstrate significant reverse remodeling after AVR. Pre-op LV dilatation may predict patients with persistent LV dysfunction post-AVR. Symptoms are less useful in children, suggesting the need for more objective data for functional assessment.     

Beneficial Effects of Residual Right Ventricular Outflow Tract Obstruction on Right Ventricular Volume and Function in Patients After Repair of Tetralogy of Fallot

Preservation of the pulmonary valve, even at the expense of a mild residual stenosis, is the current surgical policy for the management of patients with tetralogy of Fallot (TOF). This study aimed to assess the long-term effect of a residual right ventricular outflow tract obstruction (RVOTO) on RV dimension and function. This study prospectively assessed 53 children (mean age, 13.4 ± 6.4 years) after repair of TOF using cardiovascular magnetic resonance imaging. Residual RVOTO on echocardiography was defined as a peak systolic RVOT gradient of 25 mmHg or higher. Patients with RVOTO (n = 29) had significantly less pulmonary regurgitation (25.2 ± 10.6 %) than patients without RVOTO (30.8 ± 9.3 %; p = 0.05) (n = 24). Compared with patients who had no RVOTO, children with RVOTO had significantly smaller RV end-diastolic volume (94.0 ± 2.6 vs 104.0 ± 20.7 ml/m²; p < 0.05) and end-systolic volume (42.9 ± 20.0 vs 48.9 ± 13.2 ml/m²; p < 0.05), whereas RV ejection fraction did not differ significantly between the two groups (55.5 ± 8.4 vs 54.0 ± 6.6 %). Restrictive physiology, assessed by late diastolic forward flow in the main pulmonary artery, was equally distributed within the two groups (31 vs 25 %; nonsignificant difference). According to the study data, residual RVOTO after repair of TOF does not affect RV function, whereas RV dimensions and the degree of pulmonary regurgitation are more favorable in the long-term follow-up evaluation of those patients. These results confirm the beneficial effects of the current strategy for repair of TOF.     

Single-Center Outcome Analysis Comparing Reintervention Rates of Surgical Arterioplasty With Stenting for Branch Pulmonary Artery Stenosis in a Pediatric Population

Although catheter-based intervention is generally accepted as the treatment of choice for branch pulmonary artery (PA) stenosis, there are no data directly comparing both the need for reintervention and time to reintervention in patients undergoing transcatheter stenting versus surgical arterioplasty. We compared children who underwent surgical branch pulmonary arterioplasty and branch PA stent placement between January 2008 and May 2012 at a single tertiary center. Need for reintervention and mean time to reintervention were assessed using chi-square and independent sample Student t test. Thirty-seven patients were included (surgery n = 18, stent n = 19). Mean weight at initial intervention was 11.3 ± 8.8 kg for surgical and 20.1 ± 15.5 kg for stent (p = 0.041). Intervention was performed on the left PA in 17 patients, the right PA in 12 patients, and both PAs in 8 patients. Five patients had undergone previous intervention. On mean follow-up of 807 ± 415 days, 50 % (9 of 18) of the surgery cohort and 5.3 % (1 of 19) of the stent cohort required reintervention (p = 0.002). In all but one case reintervention was catheter-based. Mean time to reintervention for the surgery cohort was 272 ± 162 days and for the single stent cohort it was 150 days. When comparable age and weight groups were analyzed, reintervention was still more common in the surgery cohort (p = 0.007). Children undergoing surgical branch pulmonary arterioplasty are more likely to require reintervention than those undergoing stent placement.     

Aiming to Preserve Pulmonary Valve Function in Tetralogy of Fallot Repair: Comparing a New Approach to Traditional Management

Pulmonary valve (PV) incompetence following transannular patch (TAP) repair of tetralogy of Fallot (TOF) results in long-term morbidity and mortality. Valve-sparing repairs have recently gained recognition; however, they may be associated with residual pulmonary stenosis (PS) in patients with small PV z scores. We sought to determine whether a repair that increases the PV annulus and augments the valve leaflet with a biomaterial would result in annular growth and in longer duration of valve competence compared with TAP. Eighty patients (median age 136 days, range 4–350) who underwent surgical repair of TOF between 2010 and 2014 were included in the study. Patients were divided into three groups based on the PV intervention: balloon dilation/valvotomy (n = 29), valve-sparing transannular repair (VSTAR) (n = 19) and TAP (n = 32). Intraoperative, early postoperative and midterm follow-up echocardiographic data (median 19 months, range 1–59) were obtained. The primary outcomes were the presence and severity of pulmonary regurgitation and/or PS. Compared with TAP, VSTAR patients demonstrated significantly less severe PR with 100 % freedom of severe PR immediately post-op (vs. 0 % in TAP), 60 % at 6 months and 20 % at 20 months. There were no differences in PS between VSTAR and TAP at follow-up. A subgroup analysis of the VSTAR group was performed. PV z scores were calculated and fit to a random effects model. Patient data fit the model closely, predicting a reproducible increase in valve annulus size over time. With better short-term and comparable midterm results, VSTAR may be appropriate for TOF repair in patients with small PV that would conventionally require a TAP.     

Pulmonary artery size as an indication for thoracoscopic repair of congenital diaphragmatic hernia in neonates

Purpose

We reviewed 24 consecutive cases of prenatally or immediately postnatally diagnosed left-sided congenital diaphragmatic hernia (CDH) to evaluate pulmonary artery (PA) size as an indication for thoracoscopic repair (TR).

Methods

CDH repair is planned once echocardiography confirms improvement in pulmonary hypertension. TR is chosen if cardiopulmonary status is stable more than 10?min in the decubitus position in the neonatal intensive care unit (NICU) under conventional mechanical or high frequency oscillatory ventilation (HFOV) with/without nitric oxide (NO) and the patient appears likely to tolerate manual ventilation during transfer to the operating room. Otherwise open repair (OR) is performed in NICU. Proximal right PA (RPA) and left PA (LPA) diameters measured at birth were assessed with respect to the type of repair.

Results

10/24 had TR and 14/24 had OR. TR cases had significantly larger RPA/LPA diameters (3.52?±?0.23 vs. 3.10?±?0.56?mm, p?p?p?p?n?=?3) and cardiopulmonary instability (n?=?1).

Conclusions

TR can be considered when RPA/LPA diameters are larger than 3.0/2.5?mm, respectively, and cardiopulmonary status is stable without NO.     

Medium and Long-Term Outcomes After Bilateral Pulmonary Artery Stenting in Children and Adults With Congenital Heart Disease

Percutaneous stenting of branch pulmonary arteries (PAs) has become an important interventional therapy in the complete management of congenital heart disease. Few data exist on long-term outcomes for patients requiring placement of bilateral stents. This study aimed to determine the medium- to long-term outcomes after bilateral stenting of branch PAs in patients with congenital heart disease. A retrospective study analyzed all procedural and follow-up data on patients undergoing bilateral PA stenting during a single procedure. From October 2001 to May 2012, 26 patients underwent bilateral PA stenting (total of 62 stents). The mean age of these patients was 9.5 ± 12 years, and their mean weight was 27 ± 19 kg. The mean procedural time was 191 ± 67 min, and the mean fluoroscopy time was 50 ± 29 min. The mean gradient across the right pulmonary artery decreased from 35 ± 22 to 11 ± 12 mmHg (p < 0.001). The left pulmonary artery gradient decreased from 32 ± 17 to 10 ± 12 mmHg (p < 0.001), and the right ventricle to descending aorta pressure ratio decreased from 71 ± 18 % to 46 ± 13 % (p < 0.001). Intraprocedural adverse events were encountered in four patients (1 small PA dissection, 2 intraprocedural arrhythmias, and 1 first-degree burn on the thigh). The mean follow-up period was 41 ± 23 months. Two deaths occurred. Further interventions were required for 12 patients. Bilateral PA stenting is effective and safe, with an instantaneous significant decrease in pressure gradients. The need for reintervention is common, so continued follow-up assessment is warranted.     

Comparison of Bilateral Pulmonary Arterial Level and Diameter in Transposition of the Great Arteries

In normal anatomy, the left pulmonary artery (LPA) is usually situated higher than the right pulmonary artery (RPA); however, transposition of the great arteries (TGA), the LPA is not always situated higher than the RPA. This study was performed to clarify the relative position of the RPA and the LPA in transposition of the great arteries (TGA) as well as the implications. We reviewed 101 angiograms of patients with TGA (age 4.1 ± 1.2 months). The width of the RPA, the LPA, and the pulmonary trunk (PT) were measured just before their first branch in the frontal view. They were classified into four groups according to the ratio between the RPA and the PT (RPA/PT). The initial courses of the LPA and the RPA were compared and defined according to their height in the frontal view, and the preferential flow (or not) to the RPA was recorded. The equation of hydrodynamics was applied to evaluate the bifurcation angle. Both PAs were the same size in all cases. Forty-eight patients (47.5 %) had a RPA/PT diameter ratio < 0.49. The LPA coursed higher than the RPA in the majority of cases (81 [80.2 %]); in a minority of cases the LPA and RPA were at the same level (6 [5.9 %]); and in some cases the RPA coursed higher than the LPA (14 [13.9 %]). Patients with a high degree of PA hypoplasia tended to have both PAs at the same level or a higher-positioned RPA. Autopsy (1 of 3 cases) showed a posterior ridge against the bronchus in the higher RPA. Hydrodynamic calculation showed that the greater the angle between the RPA/PT, the greater the preferential flow. Preferential flow to the RPA in TGA did not necessarily result in LPA hypoplasia before its first branch. Higher RPA position relative to the LPA was associated with greater flow in it against the posterior bronchus. This situation was more prevalent in patients with severe PA hypoplasia.     

Renal Dysfunction is Common Among Adults After Palliation for Previous Tetralogy of Fallot

Long-term survival after tetralogy of Fallot (TOF) repair is excellent. However, little is published regarding late noncardiac complications. This study aimed to determine the prevalence and risk factors for renal dysfunction among adults after TOF repair. For this study, 56 adult patients with complete repair of TOF were identified, and their charts were retrospectively reviewed. An estimated glomerular filtration rate (eGFR) for each patient was calculated using the Modification of Diet in Renal Disease formula (MDRD). Using each patient’s eGFR, he or she was classified into stages based on the National Kidney Foundation chronic kidney disease (CKD) staging. Clinical parameters were compared among patients with and those without renal dysfunction to identify risk factors for renal impairment. The median estimated eGFR rate for the cohort was 78 ml/min/1.73 m². Based on the National Kidney Foundation CKD staging system, 54 % of the patients had at least stage 2 chronic renal disease. The risk factors identified were hypertension (p < 0.01), type 2 diabetes mellitus (p < 0.05), longer follow-up evaluation (p < 0.005), older age at complete repair (p < 0.05), and use of daily diuretics (p < 0.05). After repair of TOF, renal dysfunction is common at late follow-up evaluation. The study findings show the importance of routine assessment of renal function and the need to limit or avoid future episodes of acute kidney injury in this at-risk population.     

The Use and Outcomes of Small,Medium and Large Premounted Stents in Pediatric and Congenital Heart Disease

We sought to describe the use and outcomes of small, medium and large premounted stents in patients with congenital heart disease, including incidence of and risk factors for re-intervention and development of in-stent stenosis. Premounted stents offer several advantages over traditional manually crimped bare-metal stents, especially in small patients. There are no data describing the medium-term effectiveness and outcomes of premounted stents in congenital heart disease. We performed a single-center retrospective review of all small, medium and large premounted stents implanted over an 8-year period. Premounted stents were implanted in 71 vessels within 59 patients with a 97 % success rate. Regardless of implantation site, premounted stent implantation resulted in significant improvements in vessel size and pressure gradient (p < 0.0001). Over a median follow-up duration of 3.1 years [interquartile range (IQR) 1.3–5.2], 25 patients (43 %) required re-intervention (18 catheter based, 3 surgical and 4 hybrid) at a median time of 1.4 years (IQR 0.9–3.0) from implant. Factors associated with re-intervention included age ≤1.9 years [hazard ratio (HR) 2.4, p = 0.03], weight ≤11.5 kg (HR 2.5, p = 0.03) and bare-metal premounted stents compared to covered premounted stents (HR 4.2, p = 0.001). In-stent stenosis was diagnosed in 42 % of premounted stents which underwent follow-up angiography. No identified characteristics were associated with in-stent stenosis, including “oversizing” the premounted stent. Small, medium and large premounted stents are effective in treating vascular stenosis in congenital heart disease. Frequent follow-up is required, especially in smaller patients with expected somatic growth, and to evaluate for in-stent stenosis which occurs in nearly half of premounted stents.     

Predicting Left Ventricular Recovery After Replacement of a Regurgitant Aortic Valve in Pediatric and Young Adult Patients: Is It Ever Too Late?

The management of pediatric and adolescent patients with pure aortic valve regurgitation remains challenging and controversial (Christos et al., Eur J Cardiothorac Surg 17:125–133, 2000; Gersony and Sommerville, ACC Curr J Rev 31:97–98, 2000; Hasaniya et al., J Thorac Cardiovasc Surg 127:970–974, 2004; Sabet et al., Mayo Clin 74:14–26, 1999; Tweddell et al., J Thorac Cardiovasc Surg 129:551–558, 2005). We evaluated pediatric and young adult patients who underwent aortic valve replacement (AVR) primarily for aortic regurgitation in an effort to identify preoperative echocardiographic variables that are predictive of left ventricular (LV) recovery following AVR. Twenty-one patients with severe aortic valve regurgitation who underwent AVR were identified. Retrospective chart review for each patient was performed and transthoracic echocardiograms prior to and 6-months after AVR were analyzed. Improvement in LV size based on preoperative LV end-systolic dimension index when compared to 6-months post-AVR was observed in 68 % of the patients. Patients with persistent dilation of their left ventricles had a greater preoperative LV end-systolic dimension index (p ≤ 0.05), a greater preoperative LV end-systolic dimension z-score (p ≤ 0.002), and a lower preoperative ejection fraction (EF) (p ≤ 0.001). A similar trend was present between the two cohorts in regards to LV end-diastolic parameters (LV end-diastolic dimension index and z-score), with patients with abnormal LV size at 6-month follow-up having larger preoperative dimensions. Increasing LV systolic dimensions and declining EF appear to be predictors of poor LV recovery following AVR in pediatric and young adult patients. LV end-systolic indices appear to be more predictive than LV end-diastolic indices. AVR should be performed prior to severe LV enlargement defined as an LV end-systolic dimension z-score >4.5.     

Subpulmonary Stenosis Assessed in Midtrimester Fetuses With Tetralogy of Fallot: A Novel Method for Predicting Postnatal Clinical Outcome

This study aimed to determine whether quantification of subpulmonary stenosis (SPS) in tetralogy of Fallot (TOF) in the second-trimester fetus can predict postnatal clinical outcome measured by pulmonary valve size and/or timing or type of intervention. The study retrospectively identified fetuses with TOF from 1998 to 2010 diagnosed at 26 weeks gestation or earlier. The data evaluated included pre- and postnatal pulmonary valve z-scores (PVZ). To quantify fetal SPS, the authors created a novel index, the SPS/DAO ratio, a ratio of the minimum infundibular diameter to the descending aorta diameter (DAO). Multiple linear regression was used to predict postnatal PVZ from prenatally determined parameters, including SPS/DAO. Fetal parameters were analyzed by logistic regression for association with postnatal outcomes, namely, timing of surgery (<1 month), used as a surrogate for severity, and type of surgery [transannular patch (TAP) vs valve sparing surgery]. A total of 23 fetuses met the inclusion criteria. The mean gestational age was 21.8 ± 1.9 weeks (range, 16.6–25.4 weeks). There was excellent correlation between predicted and measured PVZ (r = 0.82; p < 0.0001) using the following derived equation: ?3.68 + (0.91 × prenatal PVZ) – (4.44 × SPS/DAO) – 3.19 (prenatal PVZ × SPS/DAO). An SPS/DAO value lower than 0.5 had 100 % sensitivity and 56 % specificity for repair before the age of 1 month, and a value lower than 0.47 had 100 % sensitivity and 75 % specificity for TAP repair. Prenatal PVZ and the SPS/DAO ratio at 26 weeks gestation or earlier can reliably predict postnatal PVZ in fetuses with TOF. Quantification of SPS with the SPS/DAO ratio identifies patients who may require early intervention secondary to disease severity and may predict the type of repair, thereby influencing prenatal counseling.     

Parvovirus B19 Myocarditis Causes Significant Morbidity and Mortality in Children

Although parvovirus B19 (PVB19) currently is the most common cause of viral myocarditis, limited pediatric data exist. Whereas other viruses infect cardiomyocytes, PVB19 targets coronary endothelium, leading to myocardial ischemia and dysfunction. A retrospective review investigated patients with polymerase chain reaction (PCR)-verified PVB19 myocarditis at Texas Children’s Hospital and Arkansas Children’s Hospital (January 2005 to August 2008). The primary end points of the study were transplant-free survival and circulatory collapse (death, mechanical support, or transplantation). For the 19 patients identified (age, 6 months to 15 years), the most common presenting symptoms were respiratory and gastrointestinal. At admission, all the patients demonstrated ventricular dysfunction requiring inotropic support (median ejection fraction, 24 %; median left ventricle end-diastolic diameter [LVEDD] z-score, 4.6). Whereas T-wave abnormalities were common, ST elevation was evident in five patients (two died and three required transplantation). Serum B-type natrietic peptide was elevated in all 12 patients tested (range, 348–8,058 pg/ml), and troponin I was high in 7 of 9 patients (range, 0.04–14.5 ng/ml). Of the 15 patients with circulatory collapse, nine received mechanical support, eight underwent successful transplantation, and five died. Only six patients (32 %) experienced transplant-free survival, and five patients had full recovery of function at discharge. In the transplant-free survival group, ST changes on presenting electrocardiography were less likely (p = 0.03), and the admission LVEDD z-score tended to be lower (3.3 vs 5.6; p = 0.08). In children, PVB19 myocarditis causes significant mortality and morbidity. Although mechanical intervention can support patients in the initial stage of decompensated heart failure, patients with PVB19 myocarditis often demonstrate persistent dysfunction requiring medical therapy and transplantation.     

Factors Associated with Serum B-Type Natriuretic Peptide in Infants with Single Ventricles

Data regarding the value of B-type natriuretic peptide (BNP) measurements in infants with a single-ventricle (SV) physiology are lacking. This analysis aimed to describe the BNP level changes in infants with an SV physiology before and after superior cavopulmonary connection (SCPC) surgery. Levels of BNP were measured by a core laboratory before SCPC (at 5.0 ± 1.6 months) and at the age of 14 months during a multicenter trial of angiotensin-converting enzyme inhibition therapy for infants with SV. Multivariable longitudinal analysis was used to model the associations between BNP levels and three sets of grouped variables (echocardiography, catheterization, growth). Multivariable analysis was performed to assess associations with patient characteristics at both visits. Associations between BNP levels and neurodevelopmental variables were investigated at the 14 month visit because neurodevelopmental assessment was performed only at this visit. The BNP level was significantly higher before SCPC (n = 173) than at the age of 14 months (n = 134). The respective median levels were 80.8 pg/ml (interquartile range [IQR], 35–187 pg/ml) and 34.5 pg/ml (IQR, 17–67 pg/ml) (p < 0.01). A BNP level higher than 100 pg/ml was present in 72 subjects (42 %) before SCPC and in 21 subjects (16 %) at the age of 14 months. In the 117 patients who had BNP measurements at both visits, the median BNP level decreased 32 pg/ml (IQR, 1–79 pg/ml) (p < 0.01). In the longitudinal multivariable analysis, higher BNP levels were associated with a higher end-systolic volume z-score (p = 0.01), a greater degree of atrioventricular (AV) valve regurgitation (p < 0.01), a lower weight z-score (p < 0.01), and a lower length z-score (p = 0.02). In multivariable analyses, a higher BNP level at the age of 14 months was associated with arrhythmia after SCPC surgery (p < 0.01), a prior Norwood procedure (p < 0.01), a longer hospital stay after SCPC surgery (p = 0.04), and a lower Bayley psychomotor developmental index (p = 0.02). The levels of BNP decreases in infants with SV from the pre-SCPC visit to the age of 14 months. A higher BNP level is associated with increased ventricular dilation in systole, increased AV valve regurgitation, impaired growth, and poorer neurodevelopmental outcomes. Therefore, BNP level may be a useful seromarker for identifying infants with SV at risk for worse outcomes.     

Increased Left Main Coronary Artery Dimensions in Children With Sickle Cell Disease

For adults with sickle cell disease (SCD), cardiac changes are well described and may account for up to one-fourth of disease-related mortality. Much less is known about heart disease in pediatric SCD patients. This retrospective study analyzed a contemporary cohort of children with SCD followed at a single tertiary care center. The study aimed to evaluate the effect of SCD on left main coronary artery (LMCA) dimensions in the contemporary pediatric population. The echocardiography database was searched for studies of children with SCD from 2000 to 2009. The LMCA diameter was remeasured offline from digital images. Digital echocardiographic studies of 68 children (35 boys) 11.7 ± 4.6 years of age with SCD were analyzed. All the patients had normal systolic function as measured by fractional shortening. The left ventricular end-diastolic dimension (LVEDD) for 34 % of the pediatric SCD patients showed a dilated LV. In 24 % of the children, a LV mass index (LVMI) greater than 50 g/m^2.7 denoted LV hypertrophy. Application of sex-specific normal values showed that 60 % of the boys and 33 % of the girls had an increased LVMI. The LMCA diameter was enlarged in 43 % of the SCD children, including 26 % with an LMCA z-score higher than 3. This study found a higher incidence of LMCA dilation in a pediatric referral population with SCD. The findings also validated an increased LVMI in the contemporary SCD patient population, which was noted previously. This study adds the need to include assessment of coronary arteries in cardiac evaluation of SCD patients, and special attention should be paid to patients with a high-normal to high coronary z-score.