Bartonella endocarditis and diffuse crescentic proliferative glomerulonephritis with a full-house pattern of immune complex deposition.

BACKGROUND: Bartonella endocarditis is often a diagnostic challenge due to its variable clinical manifestations, especially when it is first presented with involvement of organs other than skin and lymph nodes, such as the kidney. CASE PRESENTATION: This was a 13-year-old girl presenting with fever, chest and abdominal pain, acute kidney injury, nephrotic-range proteinuria and low complement levels. Her kidney biopsy showed diffuse crescentic proliferative glomerulonephritis with a full-house pattern of immune complex deposition shown by immunofluorescence, which was initially considered consistent with systemic lupus erythematous-associated glomerulonephritis (lupus nephritis). After extensive workup, Bartonella endocarditis was diagnosed. Antibiotic treatment and valvular replacement surgery were undertaken with subsequent return of kidney function to normal range. CONCLUSION: This case demonstrates the importance of considering the full clinical picture when interpreting clinical, laboratory and biopsy findings, because the treatment strategy for infective endocarditis versus lupus nephritis is drastically different.

Successful Allogeneic Stem Cell Transplant in Pediatric Patients With Diminished Left Ventricular Ejection Fractions.

Chemotherapy-associated cardiotoxicity may delay or impair the ability to administer fully myeloablative chemotherapy for stem cell transplant in those with reduced left ventricular ejection fraction. Studies in adults have been inconsistent regarding the value of ejection fraction in predicting cardiotoxicity in the posttransplant period. Recent publications, however, have demonstrated successful stem cell transplantation in adults despite low ejection fractions. This case series highlights 2 pediatric patients who were successfully treated with stem cell transplantation without posttransplant cardiac complications, despite pretransplant ejection fractions of 38% and 29%.

Registry-based trials: a potential model for cost savings?

BACKGROUND/AIMS: Registry-based trials have emerged as a potentially cost-saving study methodology. Early estimates of cost savings, however, conflated the benefits associated with registry utilisation and those associated with other aspects of pragmatic trial designs, which might not all be as broadly applicable. In this study, we sought to build a practical tool that investigators could use across disciplines to estimate the ranges of potential cost differences associated with implementing registry-based trials versus standard clinical trials. METHODS: We built simulation Markov models to compare unique costs associated with data acquisition, cleaning, and linkage under a registry-based trial design versus a standard clinical trial. We conducted one-way, two-way, and probabilistic sensitivity analyses, varying study characteristics over broad ranges, to determine thresholds at which investigators might optimally select each trial design. RESULTS: Registry-based trials were more cost effective than standard clinical trials 98.6% of the time. Data-related cost savings ranged from $4300 to $600,000 with variation in study characteristics. Cost differences were most reactive to the number of patients in a study, the number of data elements per patient available in a registry, and the speed with which research coordinators could manually abstract data. Registry incorporation resulted in cost savings when as few as 3768 independent data elements were available and when manual data abstraction took as little as 3.4 seconds per data field. CONCLUSIONS: Registries offer important resources for investigators. When available, their broad incorporation may help the scientific community reduce the costs of clinical investigation. We offer here a practical tool for investigators to assess potential costs savings.

Alterations in cerebral ventricle size in children with congenital heart disease.

PURPOSE: Children with tetralogy of Fallot (TOF) and superior cavopulmonary anastomoses (SCPA) can have chronically elevated central venous pressure (CVP), which has been postulated to put patients at risk for cerebral ventriculomegaly. We aimed to examine cerebral ventricle size in children with these congenital heart lesions before and after surgery to determine how changes in CVP affect ventricle size. METHODS: We reviewed the records of patients who underwent SCPA or TOF repair between 2006 and 2015. Patients with pre- or post-operative cranial imaging were included. Frontal-occipital (FO) horn ratios were calculated as measures of cerebral ventricle volume. Reported normal mean FO ratio is 0.37 ± 0.03. Patient characteristics including occipito-fronto circumference (OFC) and available CVP measurements were recorded. CVP, FO ratios, and OFC percentiles were compared using paired and unpaired t tests and Wilcoxon matched pairs signed-rank test as appropriate. RESULTS: We reviewed 44 patients who underwent SCPA and 31 patients who underwent TOF repair who had cranial imaging studies available. In the 22 patients who underwent SCPA and had pre- and post-operative imaging, mean FO ratios significantly increased from 0.37 ± 0.03 to 0.40 ± 0.04 (P < 0.001). In contrast, in the seven patients with TOF with pre- and post-operative imaging, FO ratio was elevated at baseline and remains so after surgical repair, 0.43 ± 0.08 to 0.42 ± 0.08 (P = 0.65). Similar patterns were noted with OFC percentiles, which were significantly increased as compared to baseline after SCPA (P < 0.001) but were not significantly changed after TOF repair (P = 0.58). Finally, when available, preoperative and postoperative CVP measurements of all patients were examined, CVP increased in patients who underwent SCPA, from 6.5 ± 2 mmHg preoperatively to 9.1 ± 2.3 mmHg postoperatively (P < 0.001), while CVP remained statistically unchanged in patients who underwent TOF repair, 12.9 ± 3.3 mmHg preoperatively to 14.4 ± 3.1 mmHg postoperatively (P = 0.2). CONCLUSION: Cerebral ventriculomegaly was observed in patients with SCPA and TOF, and the observed changes in FO ratio and OFC may be related, at least in part, to CVP.

Noncompaction cardiomyopathy and heterotaxy syndrome.

Left ventricular noncompaction cardiomyopathy (LVNC) is characterized by compact and trabecular layers of the left ventricular myocardium. This cardiomyopathy may occur with congenital heart disease (CHD). Single cases document co-occurrence of LVNC and heterotaxy, but no data exist regarding the prevalence of this association. This study sought to determine whether a non-random association of LVNC and heterotaxy exists by evaluating the prevalence of LVNC in patients with heterotaxy. In a retrospective review of the Indiana Network for Patient Care, we identified 172 patients with heterotaxy (69 male, 103 female). Echocardiography and cardiac magnetic resonance imaging results were independently reviewed by two cardiologists to ensure reproducibility of LVNC. A total of 13/172 (7.5%) patients met imaging criteria for LVNC. The CHD identified in this subgroup included atrioventricular septal defects [11], dextrocardia [10], systemic and pulmonary venous return abnormalities [7], and transposition of the great arteries [5]. From this subgroup, 61% (n = 8) of the patients developed arrhythmias; and 61% (n = 8) required medical management for chronic heart failure. This study indicates that LVNC has increased prevalence among patients with heterotaxy when compared to the general population (0.014-1.3%) suggesting possible common genetic mechanisms. Interestingly, mice with a loss of function of Scrib or Vangl2 genes showed abnormal compaction of the ventricles, anomalies in cardiac looping, and septation defects in previous studies. Recognition of the association between LVNC and heterotaxy is important for various reasons. First, the increased risk of arrhythmias demonstrated in our population. Secondly, theoretical risk of thromboembolic events remains in any LVNC population. Finally, many patients with heterotaxy undergo cardiac surgery (corrective and palliative) and when this is associated with LVNC, patients should be presumed to incur a higher peri-operative morbidity based on previous studies. Further research will continue to determine long-term and to corroborate genetic pathways.

Resolution of inferior venous baffle leak and total venous occlusion using a bare stent and the gore(®) excluder( ®) aortic extension in transposition of the great arteries after mustard procedure.

We present a patient with a history of Mustard repair for transposition of the great arteries. The patient presented with complete inferior venous baffle obstruction and a large baffle leak after several years of cyanosis. Complete relief of the obstruction and exclusion of the baffle leak were accomplished with the use of a combination of bare metal stenting and the Gore(®) Excluder(®) aortic extender. To our knowledge, this represents the first reported use of the Gore(®) Excluder(®) aortic extender in the setting of inferior venous baffle leak and associated total inferior vena cava obstruction. © 2015 Wiley Periodicals, Inc.

Utilizing a Collaborative Learning Model to Promote Early Extubation Following Infant Heart Surgery.

OBJECTIVE: To determine whether a collaborative learning strategy-derived clinical practice guideline can reduce the duration of endotracheal intubation following infant heart surgery. DESIGN: Prospective and retrospective data collected from the Pediatric Heart Network in the 12 months pre- and post-clinical practice guideline implementation at the four sites participating in the collaborative (active sites) compared with data from five Pediatric Heart Network centers not participating in collaborative learning (control sites). SETTING: Ten children's hospitals. PATIENTS: Data were collected for infants following two-index operations: 1) repair of isolated coarctation of the aorta (birth to 365 d) and 2) repair of tetralogy of Fallot (29-365 d). There were 240 subjects eligible for the clinical practice guideline at active sites and 259 subjects at control sites. INTERVENTIONS: Development and application of early extubation clinical practice guideline. MEASUREMENTS AND MAIN RESULTS: After clinical practice guideline implementation, the rate of early extubation at active sites increased significantly from 11.7% to 66.9% (p < 0.001) with no increase in reintubation rate. The median duration of postoperative intubation among active sites decreased from 21.2 to 4.5 hours (p < 0.001). No statistically significant change in early extubation rates was found in the control sites 11.7% to 13.7% (p = 0.63). At active sites, clinical practice guideline implementation had no statistically significant impact on median ICU length of stay (71.9 hr pre- vs 69.2 hr postimplementation; p = 0.29) for the entire cohort. There was a trend toward shorter ICU length of stay in the tetralogy of Fallot subgroup (71.6 hr pre- vs 54.2 hr postimplementation, p = 0.068). CONCLUSIONS: A collaborative learning strategy designed clinical practice guideline significantly increased the rate of early extubation with no change in the rate of reintubation. The early extubation clinical practice guideline did not significantly change postoperative ICU length of stay.

The Effects of Pulmonary Valve Replacement for Severe Pulmonary Regurgitation on Exercise Capacity and Cardiac Function.

Patients may develop hemodynamic abnormalities after right ventricular outflow tract (RVOT) repair. Re-intervention timing remains a dilemma. This study evaluates exercise capacity and RV function before and after intervention using age-related comparisons. Twenty-six patients with severe pulmonary regurgitation (PR) after initial repair scheduled for pulmonary valve replacement (PVR) were enrolled. Metabolic treadmill testing (EST) and MRI were obtained before and after surgery. EST results were compared with matched controls. Preoperative exercise time and peak oxygen consumption (VO2 max) were significantly diminished compared with controls but were not significantly different postoperatively. The patients were then split into age-related cohorts. When comparing pre-PVR and post-PVR exercise time and VO2 max among themselves, neither cohort showed significant differences. However, patients younger than 25 years had better postoperative results, an age-related difference not seen in the controls. Preoperative MRI showed significantly dilated RV, PR, and low normal function. After PVR, the right to left ventricular end-diastolic volume ratio (RVEDV:LVEDV) and pulmonary artery regurgitant fraction (RF) significantly decreased. There was no change in ventricular ejection fractions (EF). Severe PR, decreased RVEF, and RV dilation can significantly diminish exercise capacity. PVR improves RVEDV:LVEDV and RF, but not EF. Younger patients had better exercise capacity that was maintained postoperatively. This age-related difference was not seen in the controls, indicating that earlier intervention may preserve exercise capacity. Serial ESTs in patients with severe PR following RVOT repair may identify deteriorating exercise capacity as an early indicator for the need for PVR.

Why exercise capacity does not improve after pulmonary valve replacement.

Optimal timing of pulmonary valve replacement (PVR) for pulmonary regurgitation is a debated topic. It is logical that maximal aerobic capacity (VO2peak) would decline when a PVR is needed, but a diminished VO2peak is not always present before PVR, and previous studies show no improvement in VO2peak after PVR. This study aimed to evaluate changes in resting spirometry from pre- to post-PVR sternotomy, to determine the limiting factors of VO2peak before and after PVR, and to determine whether changes in resting lung function after PVR may explain the lack of improvement in VO2peak after surgery. For 26 patients (age, 19.7 ± 7.8 years) with a history of right ventricular outflow tract revision, the study prospectively evaluated echocardiograms, resting spirometry, and maximal exercise tests before PVR and then an average of 15 months after PVR. Flow volume loops were reviewed by a pulmonologist and categorized as obstructive, restrictive, both obstructive and restrictive, or normal. Exercise tests were interpreted using Eschenbacher's algorithm to determine the primary factors limiting exercise. No change in VO2peak or spirometry after PVR was observed. Before PVR, many patients had abnormal resting lung functions (85 % abnormal), which was unchanged after PVR (86 5 % abnormal). The majority of the patients had a ventilatory limitation to VO2peak before PVR (66.7 %), whereas 28.5 % had a cardiovascular limitation, and 4.8 % had no clear limitation. After PVR, 65.2 % of the patients had a ventilatory limitation, whereas 30.4 % had a cardiovascular limitation, and 4.4 % had no clear limitation to VO2peak. Pulmonary function did not change up to 15 months after surgical PVR. The frequency of pulmonary limitation to VO2peak after PVR did not increase. The effect of pulmonary function on exercise-related symptoms must be considered in this patient population. Improved cardiac hemodynamics are unlikely to improve VO2peak in a primarily pulmonary-limited patient.

Pulmonary limitation to exercise after repair of D-transposition of the great vessels: atrial baffle versus arterial switch.

This study evaluated resting pulmonary function and its impact on exercise capacity after atrial baffle (BAFFLE) and arterial switch (SWITCH) repair of D-transposition of the great vessels (DTGV). Previously decreased exercise capacity in DTGV patients has been primarily attributed to cardiovascular limitations, whereas pulmonary limitations have largely been overlooked. Resting flow volume loops were compared for BAFFLE (n = 34) and SWITCH (n = 32) patients. Peak exercise variables were compared for BAFFLE (n = 30) and SWITCH (n = 25). Lung disease (restrictive and/or obstructive) was present in 53% of DTGV patients (BAFFLE 62% and SWITCH 44%; p = 0.14). BAFFLE patients had a normal breathing reserve, whereas that of SWITCH patients was decreased (27.3 ± 28.3 vs. 13.0 ± 19.2; p = 0.04). BAFFLE patients attained a lower percent of predicted peak oxygen pulse (82.7 ± 20.5% vs. 94.7 ± 19.3%; p = 0.04) and peak oxygen consumption (VO(2peak)) (26.6 ± 6.7 ml/kg/min vs. 37.3 ± 8.5 ml/kg/min; p < 0.01) than SWITCH patients. Patients after surgical repair for DTGV have an underappreciated occurrence of lung disease, even post-SWITCH. SWITCH patients have diminished breathing reserves, suggesting a pulmonary limitation to VO(2peak). BAFFLE patients have lower VO(2peaks), greater breathing reserves, and lower oxygen pulses than SWITCH patients, suggesting a cardiac limitation to peak aerobic capacity with probable secondary pulmonary limitations. Treating underlying lung disease in symptomatic patients after repair of DTGV may improve functional status.

Myocardial perfusion and exercise capacity 12 years after arterial switch surgery for D-transposition of the great arteries.

Peak exercise myocardial perfusion was evaluated in patients with D-transposition of the great arteries 12 years after the arterial switch operation (SWITCH) to evaluate coronary perfusion. Gas-exchange measurements were used to assess cardiac limiting factors to exercise capacity in SWITCH patients when compared to healthy gender-matched controls (CON). Peak myocardial perfusion was evaluated in 42 patients 12 years post-SWITCH, using technetium-99 m (Tetrofosmin). SWITCH exercise data was compared to 42 gender-matched controls (CON). One symptomatic and one asymptomatic SWITCH patient had abnormal exercise myocardial perfusion; both patients had variant coronary anatomy preoperatively. SWITCH patients had lower VO(2peak) (p < 0.01), peak heart rates (p = 0.01), percentages of age-predicted peak heart rates (p < 0.01), and peak oxygen pulses indexed to body surface area (p < 0.01) than CON patients. Exercise testing with myocardial perfusion imaging helped to identify the rare SWITCH patient with coronary insufficiencies. This study demonstrates that exercise testing with myocardial perfusion scans can help identify patients at risk for myocardial events. This study also demonstrated that SWITCH patients have a mildly diminished VO(2peak) when compared to CON patients.

Impact of Major Residual Lesions on Outcomes After Surgery for Congenital Heart Disease.

BACKGROUND: Many factors affect outcomes after congenital cardiac surgery. OBJECTIVES: The RLS (Residual Lesion Score) study explored the impact of severity of residual lesions on post-operative outcomes across operations of varying complexity. METHODS: In a prospective, multicenter, observational study, 17 sites enrolled 1,149 infants undergoing 5 common operations: tetralogy of Fallot repair (n = 250), complete atrioventricular septal defect repair (n = 249), arterial switch operation (n = 251), coarctation or interrupted arch with ventricular septal defect (VSD) repair (n = 150), and Norwood operation (n = 249). The RLS was assigned based on post-operative echocardiography and clinical events: RLS 1 (trivial or no residual lesions), RLS 2 (minor residual lesions), or RLS 3 (reintervention for or major residual lesions before discharge). The primary outcome was days alive and out of hospital within 30 post-operative days (60 for Norwood). Secondary outcomes assessed post-operative course, including major medical events and days in hospital. RESULTS: RLS 3 (vs. RLS 1) was an independent risk factor for fewer days alive and out of hospital (p ≤ 0.008) and longer post-operative hospital stay (p ≤ 0.02) for all 5 operations, and for all secondary outcomes after coarctation or interrupted arch with VSD repair and Norwood (p ≤ 0.03). Outcomes for RLS 1 versus 2 did not differ consistently. RLS alone explained 5% (tetralogy of Fallot repair) to 20% (Norwood) of variation in the primary outcome. CONCLUSIONS: Adjusting for pre-operative factors, residual lesions after congenital cardiac surgery impacted in-hospital outcomes across operative complexity with greatest impact following complex operations. Minor residual lesions had minimal impact. These findings may provide guidance for surgeons when considering short-term risks and benefits of returning to bypass to repair residual lesions.

Is left ventricular noncompaction in children truly an isolated lesion?

Left ventricular noncompaction (LVNC) is a form of cardiomyopathy resulting from a disorder of endomyocardial morphogenesis. It has been associated with significant morbidity and mortality. The aim of this study was to characterize associated cardiac findings in children with LVNC and to identify risk factors associated with increased mortality. From our echocardiography database, we identified 46 patients diagnosed with LVNC between December 1999 and February 2005. The mean age at presentation was 3.6 +/- 5.6 years, and the mean duration of follow-up was 1.9 +/- 2.1 years. Left ventricular ejection fraction was decreased in 24 patients (52%; mean 39.5% +/- 13.1%). Thirty-six patients (78%) had associated cardiac lesions, including atrial septal defect (n = 16 [35%]), ventricular septal defect (n = 17 [37%]), patent ductus arteriosus (n = 14 [30%]), and Ebstein's anomaly (n = 5 [11%]). Electrocardiogram abnormalities were found in 80% of patients; most commonly they included left (n = 15 [43%]) and right ventricular hypertrophy (n = 19 [54%]). Documented arrhythmias included ectopic atrial rhythm (n = 2), junctional rhythm (n = 2), supraventricular tachycardia (n = 2), and ventricular tachycardia (n = 1). Overall mortality was 20%, and there was no association with ejection fraction, morphologic defect, or arrhythmia. Mean age at diagnosis in survivors (4.5 +/- 6.1 years) was higher than nonsurvivors (0.4 +/- 0.7 years) (p < 0.0001). LVNC is a rarely isolated form of cardiomyopathy, and it is associated with significant additional cardiac abnormalities. Although it does not have an invariably fatal course, early presentation in infancy does carry an increased risk of mortality.

Cyanosis and Stroke due to Functional Cor Triatriatum Dexter in a Neonate.

Small remnants of the right valve of the sinus venosus are commonly found in adults, but the incidence and risk associated with these embryonic remnants in neonates are not well studied. The following report describes a cyanotic neonate with a large Eustachian valve remnant creating a functional cor triatriatum dexter who was initially diagnosed with persistent pulmonary hypertension of the newborn. The cyanosis in this infant improved over the first postnatal week with conservative management, but she suffered multifocal subcortical stroke, likely related to her intracardiac shunt. The clinical presentation and questions regarding long-term management of this rare diagnosis are explored.

Consideration of pyloric stenosis as a cause of feeding dysfunction in children with cyanotic heart disease.

Feeding difficulty has been reported at a higher incidence in infants with cyanotic heart disease and single ventricle physiology necessitating specialized feeding strategies. However, structural causes of feed intolerance in this subset of patients should not be ignored. This case series highlights three recent cases of pyloric stenosis in infants with left-sided obstructive lesions at our institution. In all three cases, the initial presumed diagnosis was feeding intolerance related to heart disease, and there was significant clinical improvement following identification and correction of pyloric stenosis.

Completeness and Accuracy of Local Clinical Registry Data for Children Undergoing Heart Surgery.

BACKGROUND: Data routinely captured in clinical registries may be leveraged to enhance efficiency of prospective research. The quality of registry data for this purpose has not been studied, however. We evaluated the completeness and accuracy of perioperative data within congenital heart centers' local surgical registries. METHODS: Within 12 Pediatric Heart Network (PHN) sites, we evaluated 31 perioperative variables (and their subcategories, totaling 113 unique fields) collected via sites' local clinical registries for submission to The Society of Thoracic Surgeons Database, compared with chart review by PHN research coordinators. Both used standard STS definitions. Data were collected on 10 subjects for 2 to 5 procedures/site and adjudicated by the study team. Completeness and accuracy (agreement of registry data with medical record review by PHN coordinator, adjudicated by the study team) were evaluated. RESULTS: A total of 56,500 data elements were collected on 500 subjects. With regard to data completeness, 3.1% of data elements were missing from the registry, 0.6% from coordinator-collected data, and 0.4% from both. Overall, registry data accuracy was 98%. In total, 94.7% of data elements were both complete/non-missing and accurate within the registry, although there was variation across data fields and sites. Mean total time for coordinator chart review per site was 49.1 hours versus 7.0 hours for registry query. CONCLUSIONS: This study suggests that existing surgical registry data constitute a complete, accurate, and efficient information source for prospective research. Variability across data fields and sites also suggest areas for improvement in some areas of data quality.

Value of plasma B-type natriuretic peptide as a marker for rejection in pediatric heart transplant recipients.

We analyzed 211 consecutive plasma B-type natriuretic peptide (BNP) measurements in 59 pediatric heart transplant patients along with echocardiographic and right ventricular endomyocardial biopsy samples. Patients with a biopsy specimen negative for rejection had significantly lower BNP levels than those patients with a biopsy positive (p

Staged surgical repair of functional single ventricle in infants with unobstructed pulmonary blood flow.

OBJECTIVE: The infant with a functional single ventricle (SV) and unobstructed pulmonary blood flow (UPBF) requires early protection of the pulmonary vascular bed to ensure suitability for a subsequent Fontan procedure. Systemic obstruction by aortic arch obstruction, subaortic stenosis, or combination of both, has been widely recognized as an important risk factor for poor outcome in children with SV-UPBF who are palliated with pulmonary artery banding (PAB). We reviewed our experience with primary PAB in the subset of patients with SV-UPBF to identify risk factors for subsequent palliative procedures and Fontan completion. METHODS: Between January 1990 and May 2004, 80 patients (median age, 14 days) with functional SV and UPBF underwent PAB as their primary palliative procedure. Thirty-five neonates had concomitant aortic coarctation or interrupted aortic arch repair (44%). A Damus-Kaye-Stansel procedure was subsequently performed in 19 patients, and subaortic resection or ventricular septal defect or bulboventricular foramen enlargement was performed in five. RESULTS: There were 4 operative deaths, and 15 late deaths. The actuarial overall survival is 84% at 1 year, 76% at 5 and 15 years. Follow-up is complete in all but six children at a mean interval of 4.9+/-3.7 years (range, 2 months-15 years). Thirty-seven patients (49%; 37 of 76) have undergone the hemi-Fontan procedure (with three hospital deaths) and 40 patients (53%; 40 of 76; 12 children without previous hemi-Fontan) have undergone the completion Fontan procedure without mortality or Fontan takedown. CONCLUSION: In infants with single ventricle physiology with or without systemic outflow obstruction and unobstructed pulmonary blood flow, a strategy of pulmonary artery banding carries acceptable operative and mid-term mortality in a high-risk group of patients. Pulmonary artery banding does not compromise performance of subsequent Damus-Kaye-Stansel procedure or completion Fontan palliation.