The Subclinical Cardiomyopathy of Friedreich's Ataxia in a Pediatric Population.

BACKGROUND: Identification of a subclinical cardiomyopathy in pediatric patients with Friedreich's ataxia (FA) has not been well-described. METHODS: We performed echocardiography (Echo), cardiac magnetic resonance imaging (cMRI), and neurologic assessment in a cross-sectional analysis of 48 genetically confirmed FA subjects aged 9-17 years with moderate neurologic impairment but without a cardiovascular history. Echo- and cMRI-determined left ventricular mass were indexed (LVMI) to height in grams/m2.7. LV remodeling was categorized as concentric remodeling (CR), concentric hypertrophy (CH), or eccentric hypertrophy based upon Echo- determined relative LV wall thickness. RESULTS: Echo LVMI exceeded age-based normal values in 85% of subjects, and cMRI-determined LVMI correlated with depression of both diastolic and systolic tissue Doppler velocity (E': r = -0.65, P < .001, S': r = -0.46, P < .001) as well as increased early diastolic Doppler flow velocity/tissue velocity ratio (r= 0.55, P < .001), a marker of elevated LV filling pressure. Similar associations were found with echo-determined LV mass. Evidence of depressed LV relaxation and increased LV stiffness were observed in 88% and 71%, of subjects, respectively, despite a normal LV ejection fraction in almost all cases (mean = 60% + 7%). CR and CH were present in 40% and 44% of the study group, respectively, although significant depressions of E' and S' were observed only in subjects with CH (P < .005). CONCLUSIONS: A subclinical hypertrophic cardiomyopathy is common in pediatric FA patients and CH is associated with both diastolic and systolic dysfunction.

Cardiovascular magnetic resonance techniques and findings in children with myocarditis: a multicenter retrospective study.

BACKGROUND: Cardiovascular magnetic resonance (CMR) is increasingly used to diagnose myocarditis in adults but its use in children is not well-established. We sought to describe the presentation, CMR protocol and findings, and outcomes in a multicenter cohort of children with myocarditis. METHODS: Thirteen hospitals retrospectively identified patients meeting the following inclusion criteria: 1) diagnosis of myocarditis by the managing physicians, 2) age <21 years, 3) CMR examination within 30 days of presentation, and 4) no congenital heart disease. Clinical data and test results, including CMR findings, were abstracted from the medical record. RESULTS: For the 143 patients meeting inclusion criteria, the median age was 16.0 years (range, 0.1-20.3) and 139 (97 %) were hospitalized at the time of CMR. The median time from presentation to CMR was 2 days (0-28). The median left ventricular ejection fraction at CMR was 56 % (10-74), with 29 (20 %) below 45 %. The median right ventricular ejection fraction was 54 % (15-72), with 11 (8 %) below 40 %. There was significant variability among centers in the types of tissue characterization techniques employed (p < 0.001). Overall, late gadolinium enhancement (LGE) was used in 100 % of studies, followed by T2-weighted imaging (T2W) in 69 %, first-pass contrast perfusion (FPP) in 48 %, and early gadolinium enhancement (EGE) in 28 %. Abnormalities were most common with LGE (81 %), followed by T2W (74 %), EGE (55 %), and FPP (8 %). The CMR study was interpreted as positive for myocarditis in 117 patients (82 %), negative in 18 (13 %), and equivocal in 7 (5 %), yielding a sensitivity of 82 %. At a median follow-up of 7.1 months (0-87), all patients were alive and 5 had undergone cardiac transplantation. CMR parameters at presentation associated with persistent left ventricular dysfunction were larger left ventricular end-diastolic volume and lower left and right ventricular ejection fraction but not abnormal LGE. CONCLUSIONS: Despite significant practice variation in imaging protocol among centers, CMR had a high sensitivity for the diagnosis of myocarditis in pediatric patients. Abnormalities were most often seen with LGE followed by T2W, EGE, and FPP. These findings should be useful in designing future prospective studies.

Decision making in anomalous aortic origin of a coronary artery.

INTRODUCTION: There are many uncertainties surrounding anomalous aortic origin of a coronary artery (AAOCA) including the pathophysiology of sudden cardiac death, how to best risk stratify patients, how to best evaluate patients, who would benefit from exercise restriction, who should undergo surgical intervention, and which operation to perform. AREAS COVERED: The goal of this review is to provide a comprehensive but succinct overview of AAOCA to help clinicians with the difficult task of navigating optimal evaluation and treatment of an individual patient with AAOCA. EXPERT OPINION: Beginning in year 2012, some of our authors proposed an integrated, multi-disciplinary working group which has become the standard management strategy for patients diagnosed with AAOCA. A multi-disciplinary team with a focus on shared decision-making with the patients/families is likely necessary to optimize outcomes. Long-term follow-up and research are needed to improve our understanding of AAOCA.

Examination of Adverse Reactions After COVID-19 Vaccination Among Patients With a History of Multisystem Inflammatory Syndrome in Children.

Importance: Data are limited regarding adverse reactions after COVID-19 vaccination in patients with a history of multisystem inflammatory syndrome in children (MIS-C). The lack of vaccine safety data in this unique population may cause hesitancy and concern for many families and health care professionals. Objective: To describe adverse reactions following COVID-19 vaccination in patients with a history of MIS-C. Design, Setting, and Participants: In this multicenter cross-sectional study including 22 North American centers participating in a National Heart, Lung, and Blood Institute, National Institutes of Health-sponsored study, Long-Term Outcomes After the Multisystem Inflammatory Syndrome in Children (MUSIC), patients with a prior diagnosis of MIS-C who were eligible for COVID-19 vaccination (age ≥5 years; ≥90 days after MIS-C diagnosis) were surveyed between December 13, 2021, and February 18, 2022, regarding COVID-19 vaccination status and adverse reactions. Exposures: COVID-19 vaccination after MIS-C diagnosis. Main Outcomes and Measures: The main outcome was adverse reactions following COVID-19 vaccination. Comparisons were made using the Wilcoxon rank sum test for continuous variables and the χ2 or Fisher exact test for categorical variables. Results: Of 385 vaccine-eligible patients who were surveyed, 185 (48.1%) received at least 1 vaccine dose; 136 of the vaccinated patients (73.5%) were male, and the median age was 12.2 years (IQR, 9.5-14.7 years). Among vaccinated patients, 1 (0.5%) identified as American Indian/Alaska Native, non-Hispanic; 9 (4.9%) as Asian, non-Hispanic; 45 (24.3%) as Black, non-Hispanic; 59 (31.9%) as Hispanic or Latino; 53 (28.6%) as White, non-Hispanic; 2 (1.1%) as multiracial, non-Hispanic; and 2 (1.1%) as other, non-Hispanic; 14 (7.6%) had unknown or undeclared race and ethnicity. The median time from MIS-C diagnosis to first vaccine dose was 9.0 months (IQR, 5.1-11.9 months); 31 patients (16.8%) received 1 dose, 142 (76.8%) received 2 doses, and 12 (6.5%) received 3 doses. Almost all patients received the BNT162b2 vaccine (347 of 351 vaccine doses [98.9%]). Minor adverse reactions were observed in 90 patients (48.6%) and were most often arm soreness (62 patients [33.5%]) and/or fatigue (32 [17.3%]). In 32 patients (17.3%), adverse reactions were treated with medications, most commonly acetaminophen (21 patients [11.4%]) or ibuprofen (11 [5.9%]). Four patients (2.2%) sought medical evaluation, but none required testing or hospitalization. There were no patients with any serious adverse events, including myocarditis or recurrence of MIS-C. Conclusions and Relevance: In this cross-sectional study of patients with a history of MIS-C, no serious adverse events were reported after COVID-19 vaccination. These findings suggest that the safety profile of COVID-19 vaccination administered at least 90 days following MIS-C diagnosis appears to be similar to that in the general population.

Accuracy of Cardiac Magnetic Resonance Imaging in Diagnosing Pediatric Cardiac Masses: A Multicenter Study.

BACKGROUND: After diagnosis of a cardiac mass, clinicians must weigh the benefits and risks of ascertaining a tissue diagnosis. Limited data are available on the accuracy of previously developed noninvasive pediatric cardiac magnetic resonance (CMR)-based diagnostic criteria. OBJECTIVES: The goals of this study were to: 1) evaluate the CMR characteristics of pediatric cardiac masses from a large international cohort; 2) test the accuracy of previously developed CMR-based diagnostic criteria; and 3) expand diagnostic criteria using new information. METHODS: CMR studies (children 0-18 years of age) with confirmatory histological and/or genetic diagnosis were analyzed by 2 reviewers, without knowledge of prior diagnosis. Diagnostic accuracy was graded as: 1) single correct diagnosis; 2) correct diagnosis among a differential; or 3) incorrect diagnosis. RESULTS: Of 213 cases, 174 (82%) had diagnoses that were represented in the previously published diagnostic criteria. In 70% of 174 cases, both reviewers achieved a single correct diagnosis (94% of fibromas, 71% of rhabdomyomas, and 50% of myxomas). When ≤2 differential diagnoses were included, both reviewers reached a correct diagnosis in 86% of cases. Of 29 malignant tumors, both reviewers indicated malignancy as a single diagnosis in 52% of cases. Including ≤2 differential diagnoses, both reviewers indicated malignancy in 83% of cases. Of 6 CMR sequences examined, acquisition of first-pass perfusion and late gadolinium enhancement were independently associated with a higher likelihood of a single correct diagnosis. CONCLUSIONS: CMR of cardiac masses in children leads to an accurate diagnosis in most cases. A comprehensive imaging protocol is associated with higher diagnostic accuracy.

Biomechanical Modeling to Inform Pulmonary Valve Replacement in Tetralogy of Fallot Patients After Complete Repair.

BACKGROUND: A biomechanical model of the heart can be used to incorporate multiple data sources (electrocardiography, imaging, invasive hemodynamics). The purpose of this study was to use this approach in a cohort of patients with tetralogy of Fallot after complete repair (rTOF) to assess comparative influences of residual right ventricular outflow tract obstruction (RVOTO) and pulmonary regurgitation on ventricular health. METHODS: Twenty patients with rTOF who underwent percutaneous pulmonary valve replacement (PVR) and cardiovascular magnetic resonance imaging were included in this retrospective study. Biomechanical models specific to individual patient and physiology (before and after PVR) were created and used to estimate the RV myocardial contractility. The ability of models to capture post-PVR changes of right ventricular (RV) end-diastolic volume (EDV) and effective flow in the pulmonary artery (Qeff) was also compared with expected values. RESULTS: RV contractility before PVR (mean 66 ± 16 kPa, mean ± standard deviation) was increased in patients with rTOF compared with normal RV (38-48 kPa) (P < 0.05). The contractility decreased significantly in all patients after PVR (P < 0.05). Patients with predominantly RVOTO demonstrated greater reduction in contractility (median decrease 35%) after PVR than those with predominant pulmonary regurgitation (median decrease 11%). The model simulated post-PVR decreased EDV for the majority and suggested an increase of Qeff-both in line with published data. CONCLUSIONS: This study used a biomechanical model to synthesize multiple clinical inputs and give an insight into RV health. Individualized modeling allows us to predict the RV response to PVR. Initial data suggest that residual RVOTO imposes greater ventricular work than isolated pulmonary regurgitation.

Anomalous Aortic Origin of a Coronary Artery: Surgical Emergency?

Anomalous aortic origin of a coronary artery is a congenital condition associated with sudden cardiac death. There are no current recommendations for the acute management and urgency for this patient population. This manuscript describes and discusses two patients who presented with an acute coronary event and needed emergent intervention despite initial clinical stabilization and improvement.

Dilated cardiomyopathy following right ventricular pacing for AV block in young patients: resolution after upgrading to biventricular pacing systems.

INTRODUCTION: Cardiac resynchronization therapy (CRT) has been demonstrated to result in clinical improvement in older adult patients with dilated cardiomyopathy (DCM), specifically those with left bundle branch block and prolonged QRS duration. We sought to demonstrate the benefits of CRT on improvement in cardiac function and clinical outcome in young patients that developed congestive heart failure (CHF) and DCM following cardiac pacing for AV block. METHODS AND RESULTS: We reviewed the charts of six patients who developed CHF or low cardiac output symptoms and DCM following implantation of right ventricular (RV)-based pacing systems for AV block, and subsequently underwent CRT. Patients ranged in age from 6 months to 23.7 years (mean: 11.3 +/- 3.6 years). AV block was congenital (3), post-surgery (2), and acquired (1). Pacing had been performed for 0.1-14.5 (7.6 +/- 2.4) years prior to development of DCM. Two patients required listing for cardiac transplantation. Following CRT: (1) QRS duration shortened from 204 +/- 15 to 138 +/- 10 msec, P = 0.002, (2) left ventricular ejection fraction improved from 34 +/- 6 to 60 +/- 2%, P = 0.003, and (3) left ventricular end diastolic dimension shortened from 5.5 +/- 0.8 to 4.3 +/- 0.5 cm, P = 0.03. All patients demonstrated clinical improvement and have been weaned from CHF medications and listing for cardiac transplantation. CONCLUSIONS: CRT can benefit young patients that develop CHF and DCM following RV pacing for AV block. Upgrading to biventricular pacing systems should be considered early in the management of these patients prior to listing for cardiac transplantation.

Fetal tachycardia treated successfully with maternally administered propylthiouracil.

Background. Fetal tachycardia may result from the transplacental passage of thyroid stimulating immunoglobulins in a patient with hypothyroidism secondary to ablation of Graves' disease. Case. A 32-year-old woman, gravida 4, para 2, and abortus 1, with hypothyroidism and a history of Graves' disease, presented at 23 6/7 weeks of gestation with a persistent fetal tachycardia. The treatment of the fetal tachycardia with maternally administered digoxin and Sotalol was unsuccessful. Maternal thyroid stimulating immunoglobulins were elevated, and treatment with maternally administered propylthiouracil (PTU) resulted in a normal sinus rhythm for the remainder of the pregnancy. An induction of labor was performed at 37 weeks. Four to five days after delivery, the neonate exhibited clinical signs of hyperthyroidism necessitating treatment. Conclusion. Fetal tachycardia resulting from the transplacental passage of thyroid stimulating immunoglobulins can be successfully treated with maternally administered PTU. The neonate needs to be followed up closely as clinical signs of hyperthyroidism may occur as thyroid stimulating immunoglobulins continue to circulate in the neonate, while the serum levels of PTU decline.