Imaging and guiding intervention for tricuspid valve disorders using 3-dimensional transesophageal echocardiography in pediatric and congenital heart disease.

In the pediatric and congenital heart disease (CHD) population, tricuspid valve (TV) disorders are complex due to the variable TV morphology, its sophisticated interaction with the right ventricle as well as associated congenital and acquired lesions. While surgery is the standard of care for TV dysfunction in this patient population, transcatheter treatment for bioprosthetic TV dysfunction has been performed successfully. Detailed and accurate anatomic assessment of the abnormal TV is essential in the preoperative/preprocedural planning. Three-dimensional transthoracic and 3D transesophageal echocardiography (3DTEE) provides added value to 2-dimensional imaging in the characterization of the TV to guide therapy and 3DTEE serves as an excellent tool for intraoperative assessment and procedural guidance of transcatheter treatment. Notwithstanding advances in imaging and therapy, the timing and indication for intervention for TV disorders in this population are not well defined. In this manuscript, we aim to review the available literature, provide our institutional experience with 3DTEE, and briefly discuss the perceived challenges and future directions in the assessment, surgical planning, and procedural guidance of (1) congenital TV malformations, (2) acquired TV dysfunction from transvenous pacing leads, or following cardiac surgeries, and (3) bioprosthetic TV dysfunction.

Correlating decline in left ventricular ejection fraction and longitudinal strain in pediatric cancer patients.

PURPOSE: Left ventricular ejection fraction (LVEF) is routinely used to monitor cardiac function in cancer patients. Global longitudinal strain (GLS) detects subclinical myocardial dysfunction. There is no consensus on what constitutes a significant change in GLS in pediatric cancer patients. We aim to determine the change in GLS associated with a simultaneous decline in LVEF in pediatric cancer patients. METHODS: This is a retrospective longitudinal study of pediatric cancer patients treated with anthracyclines between October 2017 and November 2019. GLS was measured by 2-dimensional speckle tracking. The study outcome was a decline in LVEF, defined as a decrease in LVEF of ≥ 10% points from baseline or LVEF < 55%. We evaluated two echocardiograms per patient, one baseline, and one follow-up. The follow-up echocardiogram was either (1) the first study that met the outcome or (2) the last echocardiogram available in patients without the outcome. Statistical analyses included receiver operator characteristic curves and univariable and multivariable Cox proportional hazards regression. RESULTS: Out of 161 patients, 33 (20.5%) had a decline in LVEF within one year of follow-up. GLS reduction by ≥ 15% from baseline and follow-up GLS >-18% had sensitivities of 85% and 78%, respectively, and specificities of 86% and 83%, respectively, to detect LVEF decline. GLS reduction by ≥ 15% from baseline and follow-up GLS >-18% were independently associated with simultaneous LVEF decline [hazard ratio (95% confidence intervals): 16.71 (5.47-51.06), and 12.83 (4.62-35.63), respectively]. CONCLUSION: Monitoring GLS validates the decline in LVEF in pediatric cancer patients.

Relation of Right Atrial Strain to Mortality in Infants With Single Right Ventricles.

We explored associations of surveillance testing in infants with single right ventricle (sRV) physiology with clinical outcomes. This prospective, single-center study included patients with sRV who had initial palliative surgery (September 2019 to December 2020). Echocardiograms and B-type naturetic peptide (BNP) obtained as a pair within 24 hours as part of clinical care were included. The primary outcome was death/heart transplant. Secondary outcomes included interstage duration of milrinone use, hospital length of stay, and no digoxin use. sRV functional assessment (subjective grade, fractional area change, tricuspid annular plane systolic excursion, global longitudinal strain, right atrial strain [RAS]) was performed offline. Associations between echocardiography, BNP, and clinical outcomes were determined. Of 26 subjects (47 encounters), 20 had hypoplastic left heart syndrome (77%). Median age at data collection was 50 days (interquartile range 26 to 90). In most encounters (73%), sRV function was subjectively normal. Median BNP was 332 pg/ml (interquartile range 160 to 1,085). A total of 5 patients (19%) met the primary outcome and had lower RAS (14.1 vs 21.3, p = 0.038), but all other parameters were similar to transplant-free survivors. RAS (16.1%, 0.83) had the highest area under curve, followed by global longitudinal strain (-14.4%, 0.77). Higher RAS was associated with fewer days on milrinone (coefficient -1.37, 95% confidence interval [CI] -2.54 to -0.20, p = 0.02) and higher odds of digoxin use (odds ratio 1.09, 95% CI 1.01 to 1.18, p = 0.047). Higher BNP was only associated with a lower odds of digoxin use (odds ratio 0.69, 95% CI 0.5 to 0.96, p = 0.03). In conclusion, RAS is a potentially important imaging marker in infants with sRV and merits further investigation in larger studies.

Assessing the left atrium of childhood cancer survivors.

Survivors of childhood cancer are at risk of cancer therapy-related cardiac dysfunction (CTRCD) characterized by systolic impairment, with little known about diastolic function. Left atrial strain (LAS) is a surrogate measure of left ventricular filling. We hypothesized that survivors (1) have lower LAS versus controls, and (2) survivors exposed to higher anthracycline dosage have even lower LAS. Cross-sectional study of 45 survivors exposed to anthracyclines ≥ 1 year after chemotherapy and 45 healthy controls. Echo variables included mitral spectral and tissue Doppler, left ventricular ejection fraction (LV EF), LV dimension, LA volume, LV global longitudinal strain (GLS), and LAS. Peak strain (Ɛ) and strain rate (SR) at three phases were obtained: atrial contraction (ac), reservoir (res), and conduit (con). Two sub-analyses of cancer survivors were performed: (1) those with anthracycline dosage ≥ 250 mg/m2, and (2) those with Ɛres in the lowest quartile. On the whole, survivors had lower Ɛres and Ɛcon values. The majority of survivors had relatively normal LAS, while a subset had very low LAS values and were more likely to be older. Survivors exposed to ≥ 250 mg/m2 anthracycline also had lower Ɛres than those < 250 mg/m2. There were no differences in mitral spectral/tissue Doppler, LV dimension, left atrial volume, or GLS. A subset of childhood cancer survivors have lower LAS than their healthy counterparts, while most are essentially normal. Those exposed to higher anthracycline dosage have even lower Ɛres. Longitudinal study of LAS may prove useful in monitoring for CTRCD.

Left Atrial Strain Correlates with Elevated Filling Pressures in Pediatric Heart Transplantation Recipients.

BACKGROUND: Noninvasive assessment of diastolic function in pediatric heart transplantation (PHTx) patients is important for monitoring of rejection, cardiac allograft vasculopathy, and nonspecific graft failure. We hypothesized that left atrial strain (LAS) would correlate with pulmonary capillary wedge pressure (PCWP) and that cutoff values to identify elevated left ventricular (LV) filling pressure could be derived for clinical practice and future testing. METHODS: This was a secondary analysis of a prospectively collected cohort of PHTx patients undergoing same-day cardiac catheterization with biopsy and transthoracic echo. There were 70 patients with 85 clinical encounters. Traditional mitral inflow Doppler, LAS, LV diastolic strain and strain rate, and ratios for mitral E to LV diastolic strain and strain rate were assessed. Correlation with PCWP was performed, and receiver operator characteristic curves were generated for an elevated mean PCWP, acute rejection, and cardiac allograft vasculopathy. RESULTS: Decreased LAS during the atrial reservoir phase (Ɛres) correlated with higher invasively measured PCWP (r = -0.40, P < .001). An Ɛres cutoff of 14.5% had good discriminatory ability for an elevated PCWP (sensitivity 75%, specificity 82%), and Ɛres > 22.0% had 100% negative predictive value; Ɛres was superior to other measures of diastolic function. Subanalyses for recent acute rejection (n = 9) showed good discriminatory ability for Ɛres of 14.5% (sensitivity 89%, specificity 74%). CONCLUSIONS: LAS correlates with invasively measured PCWP and can identify elevated pressures better than traditional and other advanced diastolic function parameters. Use of LAS in PHTx patients may aid in noninvasive monitoring for rejection and nonspecific graft dysfunction.

State of the art review: Chemotherapy-induced cardiotoxicity in children.

Chemotherapy-induced cardiotoxicity in adults and children is a topic with a growing interest in the cardiology literature. The ability to detect cardiac dysfunction in a timely manner is essential in order to begin adequate treatment and prevent further deterioration. This article aims to provide a review on the myocardial injury process, chemotherapeutic agents that lead to cardiotoxicity, the definition of cardiotoxicity, and the methods of timely detection and treatment.

Late outcomes in children with Shone's complex: a single-centre, 20-year experience.

OBJECTIVE: Shone's syndrome is a complex consisting of mitral valve stenosis in addition to left ventricle outflow obstruction. There are a few studies evaluating the long-term outcomes in this population. We sought to determine the long-term outcomes in our paediatric population with Shone's syndrome and the factors associated with left heart growth. METHODS: All patients diagnosed with Shone's syndrome with biventricular circulation treated between 1978 and 2010 were reviewed. Baseline echocardiograms and data from catheterisations were also reviewed. Number of interventions (surgical+transcatheter), incidence of mitral valve replacement, and incidence of heart transplantation were tracked. Survival of the population and left heart structural growth were also reviewed. RESULTS: A total of 121 patients with Shone's syndrome presented at a median age of 28 days (0-17.3 years) and were followed-up for 7.2 years (0.01-35.5 years). These patients underwent 258 interventions during the study period, and the presence of coarctation was associated with repeat left heart interventions. The 10-year, transplant-free survival was 86%. Presence of pulmonary hypertension was associated with mortality. Left heart structural growth was seen for mitral and aortic valve annuli and left ventricular end-diastolic dimension over time. CONCLUSIONS: Shone's syndrome patients undergo a number of left heart interventions. Coarctation of the aorta is associated with an increased likelihood for repeat interventions. Survival appears to be more favourable than expected. Significant left heart growth will occur in the population. Pulmonary hypertension is associated with an increased risk of mortality.

Abnormal Myocardial Strain Indices in Children Receiving Anthracycline Chemotherapy.

Anthracycline chemotherapy (AC) is associated with impaired left ventricular (LV) systolic function. LV ejection fraction (EF %) obtained by two-dimensional echocardiography is the current gold standard for detection and monitoring of LV systolic function. However, dependence on LVEF has been shown to be unreliable due to its inherent limitations. Speckle tracking echocardiography (STE) measures myocardial strain and is a sensitive method to detect LV systolic dysfunction with demonstrated utility in such detection in adult and pediatric cohort studies. Compare myocardial strain indices derived by STE with LVEF to detect ACT-induced LV systolic dysfunction. Prospective, cross-sectional measurements of LV myocardial strain indices derived from STE with LVEF. Pediatric cohort of 25 patients (pts): 17 females, eight males with a mean age 9.8 ± 5.8 years, who received anthracyclines (AC); median cumulative dose ≥150 ± 124.4 mg/m(2), range 60-450 mg/m(2) showing normal LV end-diastolic diameter (mm) and normal LVEF (≥55 %) underwent STE to obtain LV myocardial strain indices: strain and strain rate. The inter- and intraobserver variability for the strain indices was 5 %. Fifteen of 25 pts (60 %) showed abnormal global longitudinal peak systolic strain (GLPSS) and 19/25 pts (76 %) showed abnormal peak circumferential strain (PCS) compared to age-matched controls (p = 0.005). In contrast, no significant differences was observed in either indices with the dose of AC. Likewise, no significant changes in the systolic or diastolic strain rate were noted with the dose of AC (r (2) = 0.0076 for peak E, r (2) = 0.072 for peak A, p = NS). GLPSS and PCS were diminished and, however, correlated poorly with the cumulative dose of AC. These observations indicate an early onset of LV systolic dysfunction by the strain indices in pts who continue to show a normal LVEF implying presence of occult LV systolic dysfunction. These novel strain indices may assist in early detection of LV systolic dysfunction with implications for monitoring and prevention of AC-induced LV systolic dysfunction.

Outcomes of anomalous left coronary artery from pulmonary artery repair: beyond normal function.

BACKGROUND: Anomalous left coronary artery from pulmonary artery (ALCAPA) is associated with high mortality if left uncorrected. We describe long-term outcomes after surgical repair and ventricular function changes on long-term follow-up. METHODS: A retrospective review of patients who had ALCAPA repair from January 1996 to December 2011 was completed. Ventricular function was assessed by shortening fraction and ejection fraction, left ventricular end-diastolic dimension, and severity of mitral regurgitation. Speckle tracking echocardiography served as a marker of early myocardial dysfunction. RESULTS: In total, 34 patients underwent ALCAPA repair at median age of 5 months (range, 3 days to 39 years). Surgical interventions included coronary translocation in 31 patients (91%), Takeuchi repair in 2 (6%), and coronary ligation in 1 patient (3%). Concomitant mitral valve repair was performed in 5 patients (15%). No patient required mechanical circulatory support postoperatively. There was no early mortality. At median follow-up of 6 years (range, 1 month to 14 years), there were 5 reoperations: 2 heart transplants (6%), 1 mitral valve replacement (3%), 1 coronary artery bypass graft (3%), and 1 ventricular septal defect closure (3%); there was 1 death 2 years after surgery. Ejection fraction improved from 21% ± 6% to 60% ± 7% (p = 0.008), mean shortening fraction from 25% ± 14% to 38% ± 5% (p = 0.01), mean left ventricular end-diastolic dimension Z-score from 6.0 ± 3.8 to 0.9 ± 0.7 (p < 0.001), and number of patients with moderate-severe mitral regurgitation from 44% (15 of 34) to 5% (1 of 21). All patients had normal ejection fraction and shortening fraction at last follow-up. Speckle tracking echocardiography showed decreased global longitudinal (p = 0.01) and circumferential strain (p = 0.03) for 11 of 14 patients (79%). CONCLUSIONS: Excellent outcomes are achieved with repair of ALCAPA without mechanical circulatory support and with low reintervention rates. Normal ejection fraction and shortening fraction do not accurately convey myocardial dysfunction in these patients.

Percutaneous atrial septal defect closure in infants and toddlers: predictors of success.

Device closure of atrial septal defect (ASD) is commonly performed in older children and adults. Infants and toddlers (age <4 years) are seldom referred for ASD closure due to size constraints. However, in many cases device ASD closure can be performed in this population. Between 2002 and 2012, 61 infants and toddlers were taken to the catheterization laboratory at our institution for ASD closure. Precatheterization transthoracic echocardiograms, intracatheterization transesophageal echocardiograms, and catheterization reports were reviewed. Fifty-three infants and toddlers presented for percutaneous ASD occlusion. Forty-eight (79 %) underwent successful closure, and 13 were referred for surgery without device attempt (n = 8) or after unsuccessful device occlusion (n = 4). Median age and weight at time of ASD closure were 2.99 years (range 0.3-3.8) and 11.7 kg (range 3.7-16.5). The device-to-septal length ratio was 0.81 (range 0.44-1.03). The 12 unsuccessful cases occurred in patients with larger defects (ASD diameter 17.5 ± 6.1 vs. 12.1 ± 4.2, p < 0.01). Deficient rims (absent or ≤ 4 mm) were seen in 9 of 12 (75 %) unsuccessful cases and in 19 of 41 (46 %) successful cases (p = 0.12). Multivariate analysis showed that patient size and ASD size were not independently associated with procedural success but that ASD size-to-patient weight ratio <1.2 (hazard ratio 9.5 [range1.7-17]) was associated with successful ASD closure. ASD device occlusion can be safely achieved in small children. An ASD size-to-patient weight ratio >1.2, not absolute patient weight or age, is associated with failure of the percutaneous approach. The midterm outcomes in these young patients are excellent.

Noncompaction of the left ventricular myocardium in a boy with a novel chromosome 8p23.1 deletion.

Interstitial deletion of chromosome 8p23.1 has been reported in patients with congenital heart defects, including atrial and ventricular septal defects, pulmonary stenosis, and complex cyanotic heart defects. GATA4, a zinc-finger transcription factor gene, has been localized to this region. GATA4 interacts with additional transcription factors in the embryogenesis of the primitive heart tube. Mutations in GATA4 are thought to be responsible for the congenital heart defects reported in association with this chromosomal deletion, and several familial point mutations leading to amino acid substitutions have also been identified. Left ventricular noncompaction (LVNC) is a clinically heterogeneous disorder characterized by LV myocardial trabeculations and intertrabecular recesses that communicate with the LV cavity. Patients may be asymptomatic or may present with evidence of severely depressed LV systolic and diastolic function. The LV may be dilated or hypertrophied, and clinical expression may be undulating. Several genetic causes of LVNC have been reported, with variable modes of inheritance, including autosomal dominant and X-linked inheritance, but relatively few responsible genes have been identified. A 12-year-old boy with a history of acute lymphoblastic leukemia, dysmorphic features, and LVNC with preserved LV systolic function was referred to the Cardiovascular Genetics Clinic at our institution. The patient was asymptomatic in terms of cardiovascular function. Chromosome microarray testing revealed an interstitial deletion in the region of 8p23.1 containing GATA4. LVNC has not been reported previously in association with this chromosome deletion. Further investigation into the role of GATA4 in patients with LVNC is warranted.

Cardiac effects of antiretroviral therapy in HIV-negative infants born to HIV-positive mothers: NHLBI CHAART-1 (National Heart, Lung, and Blood Institute Cardiovascular Status of HAART Therapy in HIV-Exposed Infants and Children cohort study).

OBJECTIVES: The aim of this study was to investigate the possible effects of antiretroviral therapy (ART) in utero on cardiac development and function in human immunodeficiency virus (HIV)-negative children. BACKGROUND: ART reduces vertical HIV transmission. Long-term cardiotoxicity after in utero exposure to ART is unknown in children but has occurred in young animals. METHODS: Using a prospective multisite cohort study design, echocardiograms taken between birth and 24 months were compared in 2 groups of HIV-negative infants of HIV-positive mothers: 136 infants exposed to ART (ART+) and 216 unexposed infants (ART-). RESULTS: Mean left ventricular (LV) mass z-scores were consistently lower in ART+ girls than in ART- girls: differences in mean z-scores were -0.46 at birth (p = 0.005), -1.02 at 6 months (p < 0.001), -0.74 at 12 months (p < 0.001), and -0.79 at 24 months (p < 0.001). Corresponding differences in z-scores for boys were smaller: 0.13 at 1 month (p = 0.42), -0.44 at 6 months (p = 0.01), -0.15 at 12 months (p = 0.37), and -0.21 at 24 months (p = 0.21). Septal wall thickness and LV dimension were smaller than expected in ART+ infants, but LV contractility was consistently about 1 SD higher at all ages (p < 0.001). In ART+ infants, LV fractional shortening was higher than in ART- infants; girls showed a greater difference. CONCLUSIONS: Fetal exposure to ART is associated with reduced LV mass, LV dimension, and septal wall thickness z-scores and increased LV fractional shortening and contractility up to age 2 years. These effects are more pronounced in girls than in boys. Fetal ART exposure may impair myocardial growth while improving depressed LV function.