Percutaneous Balloon-Expandable Stent Implantation to Treat Transverse Aortic Arch Obstruction: Medium- to Long-Term Outcomes of a Retrospective Multicenter Study.

BACKGROUND: Transverse aortic arch obstruction is a challenging lesion for which stent implantation provides a potentially important alternate therapy. The objectives were to evaluate the technical, procedural, and medium-to-long-term clinical outcomes of percutaneous stent implantation of transverse aortic arch obstruction. METHODS: This is a retrospective, multicenter study of transverse aortic arch stent implantation. Univariable and multivariable analyses were performed. RESULTS: Index catheterization included 187 stent implants in 146 patients. The median age is 14.3 years (interquartile range, 9.3-19), weight is 53 kg (30-69), and follow-up is 53 months (12-120). The most common stent design was open cell (n=90, 48%). Stents overlapped 142 arch vessels (37 carotid arteries) in 118 (81%) cases. Technical and procedural success rates were 100% and 88%, respectively. Lower weight (P=0.018), body surface area (P=0.013), and minimum-to-descending aortic diameter ratio (P<0.001) were associated with higher baseline aortic gradient. The residual gradient was inversely associated with implant and final dilation diameters (P<0.001). The combined incidence of aortic injury and stent-related complications was 14%. There were no reports of abnormal brain scans or stroke. Blood pressure cuff gradient, echocardiographic arch velocity, and hypertension rates improved within 1-year follow-up with increased antihypertensive medication use. Reintervention was reported in 60 (41%) patients at a median of 84 (22-148) months to first reintervention. On multivariable logistic regression, residual aortic gradient >10 mm Hg was associated with increased odds of reintervention at all time points when controlling for each final dilation diameter, weight, and minimum-to-descending aortic diameter ratio. CONCLUSIONS: Transverse aortic arch stent implantation has high rates of technical, procedural, and medium-to-long-term clinical success. Aortic gradient >10 mm Hg is associated with increased odds of reintervention at 1-year and most recent follow-ups. Open cell stent design was frequently used for its advantages in conformability, perfusion of arch vessels, low fracture rate, and the ability to perform effective angioplasty of side cells.

Racial and Ethnic Disparity in Multisystem Inflammatory Syndrome in Children Associated With SARS-CoV-2 in Mississippi, USA.

We aimed to study the disparity in the clinical profile and outcomes of hospitalized Multisystem Inflammatory Syndrome in Children (MIS-C) patients at our center. The second goal was to examine the temporal association with preceding SARS-CoV-2 infection by race/ethnicity in our community in Mississippi. We found the racial disparity in the prevalence of MIS-C exceeded its temporal association with SARS-CoV-2 infections. We included 51 consecutive MIS-C patients hospitalized, whose median age was 9 (interquartile range [IQR] 5-12) years, 58% were male, 71% were black, 25% were white, and 4% belonged to other groups. We found a delay between onset of symptoms and hospitalization in black patients compared with white patients with a median of 2 (IQR 0-7) vs median of 0 (0-5) urgent care visits (P = .022), respectively. Black patients were hospitalized longer (median 8, IQR 2-39 days) than whites (median 5, IQR 3-14 days), P = .047. A total of 38.9% of blacks and 23.1% of whites were admitted to intensive care unit (P = .498); 36.1% of blacks had severe cardiac involvement vs 23.1% of white patients, P = .531. Future studies of MIS-C are required to improve health equity for children.

Heart Failure with Preserved Ejection Fraction in Children.

Diastolic dysfunction (DD) refers to abnormalities in the mechanical function of the left ventricle (LV) during diastole. Severe LVDD can cause symptoms and the signs of heart failure (HF) in the setting of normal or near normal LV systolic function and is referred to as diastolic HF or HF with preserved ejection fraction (HFpEF). Pediatric cardiologists have long speculated HFpEF in children with congenital heart disease and cardiomyopathy. However, understanding the risk factors, clinical course, and validated biomarkers predictive of the outcome of HFpEF in children is challenging due to heterogeneous etiologies and overlapping pathophysiological mechanisms. The natural history of HFpEF varies depending upon the patient's age, sex, race, geographic location, nutritional status, biochemical risk factors, underlying heart disease, and genetic-environmental interaction, among other factors. Pediatric onset HFpEF is often not the same disease as in adults. Advances in the noninvasive evaluation of the LV diastolic function by strain, and strain rate analysis with speckle-tracking echocardiography, tissue Doppler imaging, and cardiac magnetic resonance imaging have increased our understanding of the HFpEF in children. This review addresses HFpEF in children and identifies knowledge gaps in the underlying etiologies, pathogenesis, diagnosis, and management, especially compared to adults with HFpEF.

Parametric Mapping Cardiac Magnetic Resonance Imaging for the Diagnosis of Myocarditis in Children in the Era of COVID-19 and MIS-C.

Myocarditis comprises many clinical presentations ranging from asymptomatic to sudden cardiac death. The history, physical examination, cardiac biomarkers, inflammatory markers, and electrocardiogram are usually helpful in the initial assessment of suspected acute myocarditis. Echocardiography is the primary tool to detect ventricular wall motion abnormalities, pericardial effusion, valvular regurgitation, and impaired function. The advancement of cardiac magnetic resonance (CMR) imaging has been helpful in clinical practice for diagnosing myocarditis. A recent Scientific Statement by the American Heart Association suggested CMR as a confirmatory test to diagnose acute myocarditis in children. However, standard CMR parametric mapping parameters for diagnosing myocarditis are unavailable in pediatric patients for consistency and reliability in the interpretation. The present review highlights the unmet clinical needs for standard CMR parametric criteria for diagnosing acute and chronic myocarditis in children and differentiating dilated chronic myocarditis phenotype from idiopathic dilated cardiomyopathy. Of particular relevance to today's practice, we also assess the potential and limitations of CMR to diagnose acute myocarditis in children exposed to severe acute respiratory syndrome coronavirus-2 infections. The latter section will discuss the multi-inflammatory syndrome in children (MIS-C) and mRNA coronavirus disease 19 vaccine-associated myocarditis.

Single-Stage Surgical Management of Atrioventricular Septal Defects with Coarctation of the Aorta.

Surgical options for coarctation of aorta (CoA) with atrioventricular septal defect (AVSD) include single-stage repair vs. staged approach with neonatal CoA repair and delayed AVSD repair. The durability of left atrioventricular valve (LAVV) function after neonatal repair is questioned, and the optimal approach remains controversial. Eighteen CoA-AVSD patients who underwent single-stage repair 2005-2015 by a single surgeon were retrospectively analyzed. Fifteen patients had complete and three had partial AVSD. Birth weight was 3.19 kg (2.17-4.08). Age at surgery was 16 days (6-127). One- and ten-year survival were 80% and 69%. Freedom from reintervention was 60% and 40% at one and ten-year respectively. Reinterventions included relief of left ventricular outflow tract obstruction (LVOTO) (n = 4), repair of cleft LAVV (n = 3), and LAVV and aortic valve replacement (n = 1). Freedom from LAVV reintervention was 85.6% and 66% at 1 and 10 years respectively. There were four deaths: two post-operative and two following hospital discharge. Mortality was due to sepsis in three patients, and heart failure related to LVOTO and LAVV insufficiency in one. At 68-month (0.6-144) follow-up the majority had mild or less LAVV regurgitation, and all had normal LV dimension and systolic function. There was no recurrent arch obstruction. Single-stage surgical repair of CoA-AVSD is feasible and reasonable. Survival and freedom from reintervention in our cohort approximate those outcomes of two-stage repair with durable left AV valve function and no recurrent arch obstruction. These patients are frequently syndromic and demonstrate mortality risk from non-cardiac causes. Consideration of a single-staged approach is warranted for appropriate patients with CoA-AVSD.

SARS-CoV-2 infection induced thyroid storm and heart failure in an adolescent girl.

We report a case of thyroid storm precipitated by SARS-CoV-2 infection in an adolescent girl with a history of Graves disease and dilated cardiomyopathy. This case highlights that SARS-CoV-2 infection can potentially trigger a thyrotoxicosis crisis and acute decompensated heart failure in a patient with underlying thyroid disease and myocardial dysfunction even in the absence of multi-system inflammatory syndrome in children. We systematically reviewed the thyrotoxicosis cases with SARS-CoV-2 infection and described its impact on pre-existing dilated cardiomyopathy.

Influenza associated with circulatory collapse and atrioventricular block in an unvaccinated child with repaired CHD.

Symptomatic, circulatory collapse occurred in an unvaccinated child with repaired congenital heart and a backup pacemaker during an Influenza B viral infection with complete atrioventricular block and pacemaker non-capture. Ventricular arrhythmias occurred during her collapse. Atrioventricular conduction recovered within 24 hours. Influenza-associated cardiac inflammation can adversely affect patients with repaired CHD. Proactive immunisation is strongly recommended.

Diagnosis and Management of the Unligated Vertical Vein in Repaired Total Anomalous Pulmonary Venous Connection.

During initial repair of supracardiac total anomalous pulmonary venous connection (TAPVC), the vertical vein (VV) is sometimes left patent (not ligated or divided) in the hope that this strategy may reduce the likelihood or severity of postoperative pulmonary hypertensive crises. We report a case of a 35-year-old pregnant patient with previously repaired supracardiac TAPVC who presented with atrial arrhythmia and right heart dilation. A cardiac magnetic resonance imaging study confirmed the diagnosis of patency of the vertical vein and right heart dilation. The VV was occluded with a catheter-delivered vascular occlusion device through a percutaneous approach, resulting in resolution of right heart dilation and arrhythmia. This case highlights the role of cross-sectional imaging as an adjunct to echocardiography in adults with repaired congenital heart disease.

Left ventricle segmental function in childhood cancer survivors using speckle-tracking echocardiography.

AIM: Anthracycline-associated cardiotoxicity in childhood cancer survivors may relate to global or segmental left ventricular abnormalities from associated thromboembolic events and myocardial microinfarcts. We characterized left ventricular segmental changes by two-dimensional speckle-tracking echocardiography in anthracycline-treated asymptomatic childhood cancer survivors. METHODS AND RESULTS: Childhood cancer survivors' echocardiograms with normal left ventricular fractional shortening >1 year after anthracycline chemotherapy were studied. Cancer-free control children had normal echocardiograms. Apical two-, three-, and four-chamber peak systolic left ventricular longitudinal and global longitudinal strain, and peak systolic left ventricular radial and circumferential strain at papillary muscle levels were analyzed. The mean (standard deviation) age was 12.7 (3.8) years in 41 childhood cancer survivors. The median (interquartile range) follow-up after anthracycline chemotherapy was 4.73 (2.15-8) years. The median (range) cumulative anthracycline dose was 160.2 (60-396.9) mg/m2. In childhood cancer survivors, the mean (standard deviation) left ventricular longitudinal strain was lower in two- (-18.6 [3.2] versus -21.3 [2.5], p < 0.001), three- (-16.3 [6.0] versus -21.7 [3.0], p < 0.001), and four- (-17.6 [2.7] versus -20.8 [2.0], p < 0.001) chamber views compared to controls. The left ventricular global longitudinal strain (-17.6 [2.7] versus -21.3 [2.0]) and circumferential strain (-20.8 [4.3] versus -23.5 [2.6], p < 0.001) were lower in childhood cancer survivors. Among childhood cancer survivors, 12 out of 16 left ventricular segments had significantly lower longitudinal strain than controls. CONCLUSIONS: Asymptomatic anthracycline-treated childhood cancer survivors with normal left ventricular fractional shortening had lower global longitudinal and circumferential strain. The left ventricular longitudinal strain was lower in majority of the segments, suggesting that anthracycline cardiotoxicity is more global than regional.

Treatment of a Child With Submassive Pulmonary Embolism Associated With Hereditary Spherocytosis Using Ultrasound-Assisted Catheter-Directed Thrombolysis.

Background: The clinical presentation of hereditary spherocytosis varies from no symptoms to severe hemolytic anemia requiring splenectomy. Splenectomy imposes the risk of hypercoagulability and acute pulmonary embolism. Catheter-directed thrombolysis is an established treatment for submassive pulmonary embolism in adults. However, the literature regarding its use in children is limited. Case Report: We present the case of a 12-year-old male with hereditary spherocytosis who was diagnosed with pulmonary embolism and successfully treated with catheter-directed thrombolysis. The patient was initially treated with 10.5 mg of recombinant tissue plasminogen activator (r-tPA) delivered over 8 hours. However, because of minimal clinical and hemodynamic improvement, a second course of thrombolytic was administered for an additional 24 hours (25 mg of r-tPA), and the treatment resulted in marked clinical and hemodynamic improvement. Clot resolution was confirmed via angiography. The patient was discharged on enoxaparin and with regular follow-up. One year later, the patient was asymptomatic on enoxaparin. Conclusion: This case demonstrates that catheter-based treatment of submassive pulmonary embolism restores hemodynamic stability and thus is an alternative to surgery or systemic thrombolysis, even in the pediatric setting. While catheter-directed thrombolysis is a safe and effective alternative to systemic thrombolysis, further research is needed to establish appropriate dosing and indications in the adolescent population.

Does Restrictive Lung Function Affect the Exercise Capacity in Patients with Repaired Tetralogy of Fallot?

Patients with repaired Tetralogy of Fallot (rTOF) have decreased exercise capacity (XC) and restrictive lung function (RLF). Our objective was to determine the association between RLF and impaired XC in patients with rTOF. This was a single center retrospective review of patients with rTOF who underwent a cardiopulmonary treadmill exercise testing and spirometry from 2005 to 2015. Patients with a respiratory exchange ratio ≥ 1.05 and peak heart rate > 90% of predicted value were included. Forced vital capacity (FVC) and Forced expiratory volume in 1st second of forceful expiration (FEV1) were used to classify the lung function. Exercise parameters such as peak oxygen uptake (VO2), % of predicted VO2 (%VO2), Metabolic equivalents (METS), and exercise time (ET) were compared between the two groups (i) compared patients with normal lung function (normal FEV1, FVC, and FEV1/FVC > 80%) (ii) RLF (FVC < 80%, normal or increased FEV1/FVC > 80%). In our cohort (n = 151, 52% male, mean age ± SD of 22.3 ± 9.1 years), patients with RLF (n = 73) compared to those with normal lung function (n = 86) had a lower peak VO2 (30.8 ± 8.6 vs. 36.6 ± 9.8 mL/kg/min; p < 0.001) and shorter exercise time (9:23 ± 1:78 vs. 10:23 ± 1:62 min, p < 0.001). On multivariate regression analysis, RLF was independently associated with reduced XC (VO2%) (ß-coefficient - 0.182, p < 0.02) after controlling for age and gender. RLF is common in patients with rTOF and is associated with decreased XC. The contribution of RLF to reduced XC in this population should be considered prior to therapeutic decisions.

Pediatric malignancies: Is the prechemotherapy left ventricular function normal?

PURPOSE: We compared the left ventricular (LV) systolic function in children with cancer before initiation of chemotherapy with matched controls using speckle tracking echocardiography. METHODS AND RESULTS: In this retrospective study, we analyzed the echocardiograms of 89 cancer patients before the initiation of chemotherapy and 82 age- (8.4 ± 5.2 vs. 8.9 ± 3.9 years, P = .4) and gender-matched (64% vs. 67%, males, P = .4) healthy controls. Peak systolic LV longitudinal strain (LS) was significantly lower in cancer patients in apical two (-19.8 ± 3.0 vs. -23.5 ± 4.0, P < .001), three (-19.4 ± 3.2 vs. -23.4 ± 4.0, P < .001), and four-chamber views (-19.7 ± 3.4 vs. -22.5 ± 3.0, P < .001) compared to controls, as was global longitudinal strain (GLS) (-19.8 ± 2.7 vs. -23.4 ± 3.2, P < .001). The prechemotherapy group also had a higher E/e' ratio compared to controls at the septal (9.3 ± 3.9 vs. 7.9 ± 1.7, P = .005) and lateral annulus (7.9 ± 3.3 vs. 5.9 ± 1.4, P < .001) of the mitral valve. The LV ejection fraction was lower in cancer patients compared to controls (63.5 ± 4.9 vs. 66.8 ± 4.1, P < .001), although still within normal limits. There were no differences in LV myocardial performance index (0.30 ± 0.05 vs. 0.30 ± 0.09, P < .65) and shortening fraction (35.8 ± 5.2 vs. 36.1 ± 6.1, P < 0.75) between the two groups. Subgroup analysis showed no difference in LV GLS between patients with solid tumors (n = 56) and blood cancers (n = 33) (GLS -19.2 ± 2.9 vs. 19.5 ± 2.4, P > 0.05). CONCLUSION: Our data demonstrating abnormalities in LV GLS in pediatric cancer patients even prior to initiation of chemotherapy are novel and perplexing. Further longitudinal follow-up is required to assess the implications of this abnormal LV function in these patients.

Cardiovascular Evaluation of Children With Malignancies.

PURPOSE OF REVIEW: The anthracycline (AC) group of drugs is widely used for cancer chemotherapy and has improved outcomes in many childhood malignancies. However, cardiovascular complications are major causes of morbidity and mortality in AC recipients, with the greatest risk factor being a higher cumulative dosage. The purpose of this review is to describe the etio-pathogenesis and risk factors of AC induced cardiotoxicity, with emphasis on currently available and emerging modalities of non-invasive imaging in its surveillance, and to review guidelines on its prevention and treatment. RECENT FINDINGS: Presently, ejection fraction and shortening fraction derived from two-dimensional echocardiography are the most widely used parameter for monitoring of cardiac function in childhood cancer survivors. The newer speckle tracking echocardiography has shown potential to detect abnormalities in ventricular function prior to the conventional measures such as ejection fraction and shortening fraction. When available, three-dimensional echocardiography should be used as it allows for more accurate estimation of ejection fraction. Newer magnetic resonance imaging (MRI) techniques, such as delayed enhancement and T1 mapping, are useful adjuncts for cardiac evaluation in cancer survivors, especially in patients with poor echocardiographic windows. Early detection and management of cardiovascular diseases is one of the major goals in the long-term follow-up of childhood cancer survivors. In addition to conventional two-dimensional echocardiography, newer techniques such as speckle tracking echocardiography and three-dimensional echocardiography should be incorporated due to its ability to detect early changes in anthracycline-induced cardiotoxicity. However further research are needed to guide changes in management due to abnormalities in speckle tracking echocardiography.

Catheter-directed therapy for acute pulmonary embolism in children.

BACKGROUND: Acute pulmonary embolism is a life-threatening condition and rarely occurs in children. In adults, catheter-directed therapy emerges as a potentially safer and effective therapeutic option. However, there is a paucity of data on the safety and efficacy of catheter-directed therapy for pulmonary embolism in children. We report a single-centred experience of catheter-directed therapy for acute pulmonary embolism in children. METHODS: This is a retrospective study of children who had no CHD and underwent catheter-directed therapy at Detroit Medical Center during a 12-year period from 2005 to 2017. Demographic and clinical data associated with pulmonary embolism were collected along with the outcome. RESULTS: A total of nine patients of median age 16 years with the range from 12 to 20 received catheter-directed therapy for sub-massive (n = 6) and massive pulmonary embolism (n = 3). Among nine patients, one patient received Angiojet thrombectomy and balloon angioplasty, whereas eight patients received catheter-directed thrombolysis using tissue plasminogen activator through infusion catheters (n = 3) or EkoSonic ultrasound-accelerated thrombolysis system (n = 5). In four out of five patients treated with EkoSonic, significant clinical improvement was noticed within 24 hours. Among seven patients who survived, two patients had minor gastrointestinal bleeding with median hospital stay of 8 days with the range from 5 to 24 days, and two patients with massive pulmonary embolism died possibly due to delayed institution of catheter-directed therapy. CONCLUSION: Catheter-directed therapy with/without EkoSonic is an emerging alternative therapy for sub-massive and massive pulmonary embolism in children. A timely institution of catheter-directed therapy appeared important to improve the outcome.

Late Cardiotoxicity: Issues for Childhood Cancer Survivors.

OPINION STATEMENT: Cardiovascular-related morbidity is a substantial health burden in survivors of childhood cancers. This burden is gaining importance as this population increases through advancements in therapy. Anthracyclines are commonly used agents that are known to cause late cardiotoxicity. Cardiotoxicity is also increased by other risk factors, such as concurrent radio- or chemotherapy, younger age at diagnosis, female sex, comorbidities, lifestyle factors, and genetic factors, such as hemochromatosis gene mutations. Treatment of late cardiotoxicity depends on the type of cardiac abnormalities and consists of pharmacotherapy, mechanical support, or heart transplantation. Because cardiotoxicity is progressive and often irreversible, prevention, risk reduction, and early detection are of utmost importance. The cardioprotectant dexrazoxane decreases anthracycline cardiotoxicity. Screening for other risk factors at the time of diagnosis may identify risk that when present, if used to tailor therapy, may reduce the severity of cardiac damage. The effects of exercise and other lifestyle changes in reducing the cardiovascular diseases in cancer survivors are unclear. However, it may be beneficial to encourage survivors to engage in physical activity tailored to survivor medical status, but with close monitoring.