Biomarker sST2 in Adults with Transposition of the Great Arteries Palliated by Mustard Procedure: A Five-Year Follow-up.

The Mustard procedure was an early cardiac surgery for transposition of the great arteries (TGA). Despite being successful, it has been associated with long-term arrhythmias and heart failure. A key factor complicating management in adults with congenital heart disease (CHD) is the deficiency of biomarkers predicting outcome. Soluble suppression of tumorogenicity-2 (sST2) is secreted by cardiomyocytes in response to mechanical strain and fibrosis. We hypothesized that adults with a Mustard procedure would have higher levels of sST2 than healthy individuals, and this would correlate with clinical outcome. We performed a single-center study in patients managed during childhood with a Mustard procedure versus age-matched controls. Clinical and demographic data were collected and biomarkers (sST2, cTnI, BNP, lipid panel, insulin, and glucose) were obtained. There were 18 patients (12 male) in the Mustard cohort and 18 patients (6 male) in the control group (22-49 years, mean of 35.8 vs. mean 32.6 years, respectively, p = ns). Nine Mustard subjects were NYHA class II, and 9 subjects were class III. The control group was asymptomatic. sST2 in the Mustard group was elevated in 56% vs. 17% in controls (p = 0.035). Of the Mustard subjects with elevated sST2, 60% had elevated cTnI and BNP, and 90% had low HDL. Over five years, the Mustard patients with elevated sST2 values had greater medication use, arrhythmias, hospitalizations, and ablation/pacer implantations than Mustard subjects with normal sST2. Mustard subjects with elevated sST2 had other biomarker abnormalities and clinically worse outcomes. Thus, sST2 may add a predictive value to cardiac-related morbidity and mortality.

Recurrent takotsubo cardiomyopathy in a child.

Takotsubo cardiomyopathy or transient apical ballooning syndrome very rarely presents in children. In all patients with takotsubo, it is estimated that only 3.5% will have recurrence. In this study, we describe a case of recurrent takotsubo cardiomyopathy in a child, likely triggered by status epilepticus.

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.

Bone density in children with single ventricle physiology.

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 single ventricle (SV). Children with this defect are often treated with warfarin, suspected to negatively impact BMD in adults. We assessed BMD in patients with 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 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 and 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.

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.

Abdominal coarctation and associated comorbidities in children.

OBJECTIVE: The purpose of this study is to report a single institution's experience with abdominal coarctation in children and report associated comorbidities. BACKGROUND: Abdominal coarctation is a rare condition, accounting for less than 2% of aortic coarctations. Single patients with abdominal coarctation have been reported with additional vascular disease in pediatric patients. METHODS: Our echocardiography database between January 2001 and January 2012 was searched to identify all patients with abdominal coarctation. Relevant clinical data were reviewed. RESULTS: Nine patients were identified with abdominal coarctation. Median age at diagnosis was 4.7 years (IQR 1.1-14.3 years). Additional cardiac diagnoses were found in three patients: one had moderate aortic regurgitation and aortic root dilatation; one had mild aortic regurgitation, severe mitral regurgitation, and atrial flutter; and one had a thoracic coarctation previously repaired. Eight patients (89%) had an associated noncardiac comorbidity. Comorbidities included: Takayasu arteritis (n = 3), systemic lupus erythematosus (n = 1), epidermal nevus syndrome (n = 1), abdominal hemangioma (n = 1), Williams syndrome (n = 1), and renal artery stenosis (n = 2). Intervention was performed in four patients (57%): two underwent surgical grafting and two had angioplasty with stent placement. Patients with surgical grafting required no further intervention, whereas both patients who underwent angioplasty and stenting required further stent placement. CONCLUSION: Abdominal coarctation is a rare anomaly. It is frequently associated with other vascular abnormalities. Vasculitis should be suspected in children with abdominal coarctation. All patients, even if treated, require continued close observation.

Comparison between transthoracic echocardiography and cardiac magnetic resonance imaging in patients status post atrial switch procedure.

OBJECTIVES: This study compares image quality, cost, right ventricular ejection fraction analysis, and baffle visualization between transthoracic echocardiography and cardiac magnetic resonance imaging in those status post atrial switch for transposition of the great arteries. BACKGROUND: This population requires imaging for serial evaluations. Transthoracic echocardiography is often first line but has drawbacks, many of which are addressed by cardiac magnetic resonance imaging. METHODS: Twelve patients (mean age 25 years) with relatively concurrent (mean 157 days) studies were included. Three separate echocardiography and magnetic resonance imaging physicians independently analyzed baffles, image quality, and right ventricular ejection fractions. Institutional and Medicaid charges were compared. RESULTS: For right ventricular ejection fraction, echocardiography (36.1%) underestimated cardiac magnetic resonance imaging (47.8%, P = .002). Image quality for transthoracic echocardiography was significantly rated lower than cardiac magnetic resonance imaging (P = .002). Baffles were better seen in cardiac magnetic resonance imaging (transthoracic echocardiography vs. cardiac magnetic resonance imaging: superior vena cava 86% vs. 100% [P = .063]; inferior vena cava 33% vs. 97% [P = .002]; pulmonary vein 92% vs. 100% [P = .250]). Comparing hospital charges and Medicaid reimbursement, transthoracic echocardiography respectively costs 18% and 38% less than cardiac magnetic resonance imaging. CONCLUSIONS: In conclusion, transthoracic echocardiography underestimated right ventricular ejection fraction compared to cardiac magnetic resonance imaging. Cardiac magnetic resonance imaging had consistently higher image quality and better visualization of the baffles. Cost differences are minimal. We propose that cardiac magnetic resonance imaging be considered first line for imaging in certain patients' status post atrial switch procedure.

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.

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.

Outcome of cardiac thrombi in infants.

Use of central lines in the neonatal intensive care unit (NICU) has led to the formation of intracardiac thrombi. A paucity of data exists on the management of neonatal cardiac thrombi, with the few reported cases focusing on outcomes following thrombolytic therapy. This study was undertaken to evaluate the outcome of cardiac thrombi in neonates who do not receive thrombolytic therapy. Nineteen patients younger than 3 months of age diagnosed with cardiac thrombi were included. All 19 patients had a central line. Management consisted of a combination of antibiotics and low-molecular-weight heparin (n = 16) or surgical removal (n = 2). In one case, no treatment was instituted. One patient was lost to follow-up after partial resolution of the thrombus. Complete thrombus resolution occurred in 18 patients, 9 with negative blood cultures and 9 with positive blood cultures. It took longer for resolution of thrombi associated with positive blood cultures than for sterile thrombi. No patient had evidence of thrombus embolization. From these data we concluded that the natural history of cardiac thrombi is resolution. Infected thrombi require more prolonged therapy. Surgery is seldom required and thrombolytics are not usually necessary for clot resolution.

Long-term functional outcome of patients following the mustard procedure: the next decade of follow-up.

BACKGROUND: Nearly 10 years ago, we studied a population of patients with d-transposition of the great arteries (DTGA) who had undergone the Mustard procedure 8-26 years earlier. The present study was undertaken to determine how that cohort of patients is currently functioning. METHODS: Of the 45 original patients, 44 were located. Six (13%) had either died (n = 4) or received a cardiac transplant (n = 2). In total, 35 of the remaining 38 patients (78%) chose to undergo testing. Systemic right ventricular ejection fraction (RVEF) was estimated using radionuclide angiocardiography. Exercise stress testing, echocardiography, Holter monitoring, and a quality of life questionnaire were also performed. RESULTS: Those 6 that died or received cardiac transplantation did so between 16 and 25 years of age. The surviving participants ranged in age from 19 to 37 years. Peak oxygen consumption was significantly diminished at 27.7 +/- 6.9 mL/kg/min. Comparison of exercise duration from the original study demonstrated a significant decrease (11.2 +/- 2.2 minutes to 9.1 +/- 2.9 minutes) (P < 0.001). Comparison of RVEF data from the original study did not demonstrate a significant decrease (0.54 +/- 0.10 to 0.53 +/- 0.10) (P = 0.27). Quality of life data suggested that Mustard patients do not score as well in physical functioning, general health, and level of energy as normal adults, but are comparable with adult patients with other chronic diseases. Mustard patients are similar to normal adults and feel better than other adults with chronic illness in their interpretation of social functioning and bodily pain. CONCLUSION: Cardiac mortality of 13% occurred during the second and third decade of life in this cohort of patients with DTGA palliated by the Mustard procedure. Despite continuing deterioration in exercise performance, right ventricular function, and cardiac rhythm, many surviving patients with DTGA continue to lead normal lives into the 4th decade after Mustard procedure.

Delayed magnetic resonance imaging contrast enhancement of synthetic ventricular septum.

This is a report of a magnetic resonance imaging with delayed contrast enhancement on an adult patient with double-inlet left ventricle and L-transposition of the great arteries who has undergone staged ventricular septation in childhood. This report is unique demonstration of delayed contrast enhancement of the synthetic Teflon septum.