Left Ventricular Outflow Tract Obstruction in Congenital Heart Disease: The Role of Cardiovascular Computed Tomography in Surgical Decision Making.

Patients with many forms of congenital heart disease (CHD) and hypertrophic cardiomyopathy undergo surgical intervention to relieve left ventricular outflow tract obstruction (LVOTO). Cardiovascular Computed Tomography (CCT) defines the complex pathway from the ventricle to the outflow tract and can be visualized in 2D, 3D, and 4D (3D in motion) to help define the mechanism and physiologic significance of obstruction. Advanced cardiac visualization may aid in surgical planning to relieve obstruction in the left ventricular outflow tract, aortic or neo-aortic valve and the supravalvular space. CCT scanner technology has advanced to achieve submillimeter, isotropic spatial resolution, temporal resolution as low as 66 msec allowing high-resolution imaging even at the fast heart rates and small cardiac structures of pediatric patients ECG gating techniques allow radiation exposure to be targeted to a minimal portion of the cardiac cycle for anatomic imaging, and pulse modulation allows cine imaging with a fraction of radiation given during most of the cardiac cycle, thus reducing radiation dose. Scanning is performed in a single heartbeat or breath hold, minimizing the need for anesthesia or sedation, for which CHD patents are highest risk for an adverse event. Examples of visualization of complex left ventricular outflow tract obstruction in the subaortic, valvar and supravalvular space will be highlighted, illustrating the novel applications of CCT in this patient subset.

Baseline Echocardiography and Laboratory Findings in MIS-C and Associations with Clinical Illness Severity.

Children with COVID-associated multisystem inflammatory syndrome (MIS-C) may develop severe disease. We explored the association of admission echocardiographic and laboratory parameters with MIS-C disease severity. This retrospective, single center study of consecutive MIS-C patients (4/2020-12/2021) excluded those with preexisting cardiomyopathy, congenital heart disease, or prior cardiotoxic therapy. Our hypothesis was that worse admission echocardiographic and laboratory parameters were associated with more severe disease based on vasoactive medication use. Univariable and multivariable logistic regression models assessed the association between vasoactive medication use and baseline variables. Of 118 MIS-C patients, median age was 7.8 years (IQR 4.6, 11.8), 48% received vasoactive medication. Higher admission brain natriuretic peptide [OR 1.07 (95% CI 1.02,1.14), p = 0.019], C-reactive protein [OR 1.08 (1.03,1.14), p = 0.002], troponin [OR 1.05 (1.02,1.1), p = 0.015]; lower left ventricular ejection fraction [LVEF, OR 0.96 (0.92,1), p = 0.042], and worse left atrial reservoir strain [OR 0.96 (0.92,1), p = 0.04] were associated with vasoactive medication use. Only higher CRP [OR 1.07 (1.01, 1.11), p = 0.034] and lower LVEF [0.91 (0.84,0.98), p = 0.015] remained independently significant. Among those with normal admission LVEF (78%, 92/118), 43% received vasoactive medication and only higher BNP [OR 1.09 (1.02,1.19), p = 0.021 per 100 pg/mL] and higher CRP [OR 1.07 (1.02,1.14), p = 0.013] were associated with use of vasoactive medication. Nearly half of all children admitted for MIS-C subsequently received vasoactive medication, including those admitted with a normal LVEF. Similarly, admission strain parameters were not discriminatory. Laboratory markers of systemic inflammation and cardiac injury may better predict early MIS-C disease severity.

Left Atrial Strain in Multisystem Inflammatory Syndrome in Children and Associations with Systemic Inflammation and Cardiac Injury.

Multisystem inflammatory syndrome in children (MIS-C) commonly involves cardiac injury with both systolic and diastolic dysfunction. Left atrial strain (LAS) detects subclinical diastolic dysfunction in adults but is infrequently used in children. We evaluated LAS in MIS-C and the associations with systemic inflammation and cardiac injury. In this retrospective cohort study, LAS parameters [reservoir (LAS-r), conduit (LAS-cd), and contractile (LAS-ct)] obtained from admission echocardiograms of MIS-C patients were compared to healthy controls and between MIS-C patients with and without cardiac injury (BNP > 500 pg/ml or troponin-I > 0.04 ng/ml). Correlation and logistic regression analyses were performed to assess LAS associations with admission inflammatory and cardiac biomarkers. Reliability testing was performed. We identified 118 patients with MIS-C and 20 healthy controls. Median LAS parameters were reduced in MIS-C patients compared to controls (LAS-r: 31.8 vs. 43.1%, p < 0.001; LAS-cd: - 28.8 vs. - 34.5%, p = 0.006; LAS-ct: - 5.2 vs. - 9.3%, p < 0.001) and reduced in MIS-C patients with cardiac injury (n = 59) compared to no injury (n = 59) (LAS-r: 29.6 vs. 35.8%, p = 0.001; LAS-cd: - 26.5 vs. - 30.4%, p = 0.036; LAS-ct: - 4.6 vs. - 9.3%, p = 0.008). A discrete LAS-ct peak was absent in 65 (55%) MIS-C patients but present in all controls (p < 0.001). Procalcitonin correlated strongly with averaged E/e' (r = 0.55, p = 0.001). Moderate correlations were found for ESR and LAS-ct (r = - 0.41, p = 0.007) as well as BNP and LAS-r (r = - 0.39, p < 0.001) and LAS-ct (r = 0.31, p = 0.023). Troponin-I had only weak correlations. Intra-rater reliability was good for all LAS parameters, and inter-rater reliability was good to excellent for LAS-r, and fair for LAS-cd and LAS-ct. LAS analysis, particularly the absence of a LAS-ct peak, was reproducible and may be superior to conventional echocardiographic parameters for detecting diastolic dysfunction in MIS-C. No strain parameters on admission were independently associated with cardiac injury.

Association of Childhood Blood Pressure with Left Atrial Size and Function: Study of High Blood Pressure in Pediatrics-Adult Hypertension in Youth (SHIP AHOY).

OBJECTIVE(S): To evaluate the cross-sectional association of cardiovascular disease risk factors with left atrial (LA) size and function among healthy youth, aged 11-18 years, with a wide range of blood pressures (BPs). STUDY DESIGN: Echocardiographic images of youth enrolled in the Study of High Blood Pressure in Pediatrics: Adult Hypertension Onset in Youth study were analyzed for LA measurements. The association of casual BP, ambulatory BP, and other cardiovascular disease risk factors with LA size and function were determined using descriptive statistics and multivariable regression. Regression models adjusting for age, sex, race, and body mass index z score determined the independent association between ambulatory systolic BP indices (mean systolic BP/50th %ile systolic BP) and BP phenotypes with LA outcomes while exploratory analyses investigated for additional predictors of LA outcomes. RESULTS: The study population consisted of 347 youth: median age 15.7 years, 60% male and 40% non-White. Greater-risk casual systolic BP groups had worse cardiometabolic profiles but no differences in LA size and function. Each 0.1 increase in ambulatory systolic BP day or night index was associated with a 9.9 mL/m2 increase in LA volume/body surface area (LAV/BSA; 95th% CI 2.8-17.0, P = .006) and a 6.8 mL/m2 increase in LAV/BSA (95th% CI 0.8-12.8, P = .03), respectively. Ambulatory hypertension was associated with greater odds of abnormal LAV/BSA, defined as >75th %ile (2014 ambulatory BP monitoring criteria: OR 3.2 [95th% CI 1.4-7.2; P = .002]; 2022 ambulatory BP monitoring criteria: OR 2.1 [95th% CI 1.0-4.1; P = .008]). CONCLUSIONS: Increasing ambulatory systolic BP and ambulatory hypertension are independently associated with LAV/BSA.

Arrhythmia in hypertrophic cardiomyopathy: Risk prediction using contrast enhanced MRI, T1 mapping, and personalized virtual heart technology.

BACKGROUND: Hypertrophic cardiomyopathy (HCM), a disease with myocardial fibrosis manifestation, is a common cause of sudden cardiac death (SCD) due to ventricular arrhythmias (VA). Current clinical risk stratification criteria are inadequate in identifying patients who are at risk for VA and in need of an implantable cardioverter defibrillator (ICD) for primary prevention. OBJECTIVE: We aimed to develop a risk prediction approach based on imaging biomarkers from the combination of late gadolinium contrast-enhanced (LGE) MRI and T1 mapping. We then aimed to compare the prediction to a virtual heart computational risk assessment approach based on LGE-T1 virtual heart models. METHODS: The methodology involved combining short-axis LGE-MRI with post-contrast T1 maps to define personalized thresholds for diffuse and dense fibrosis. The combined LGE-T1 maps were used to evaluate imaging biomarkers for VA risk prediction. The risk prediction capability of the biomarkers was compared with that of the LGE-T1 virtual heart arrhythmia inducibility simulation. VA risk prediction performance from both approaches was compared to clinical outcome (presence of clinical VA). RESULTS: Image-based biomarkers, including hypertrophy, signal intensity heterogeneity, and fibrotic border complexity, could not discriminate high vs low VA risk. LGE-T1 virtual heart technology outperformed all the image-based biomarker metrics and was statistically significant in predicting VA risk in HCM. CONCLUSIONS: We combined two MR imaging techniques to analyze imaging biomarkers in HCM. Raw and processed image-based biomarkers cannot discriminate patients with VA from those without VA. Hybrid LGE-T1 virtual heart models could correctly predict VA risk for this cohort and may improve SCD risk stratification to better identify HCM patients for primary preventative ICD implantation.

Left Ventricular Diastolic Dysfunction Among Youth with Obesity and History of Elevated Blood Pressure.

OBJECTIVE: To assess prevalence of and factors associated with left ventricular diastolic dysfunction (LVDD) in youth with obesity and elevated blood pressure (BP). STUDY DESIGN: This was a cross-sectional analysis of baseline and follow-up visits of 83 youth, 5-21 years, evaluated for overweight/obesity and elevated BP in a multidisciplinary clinic. LVDD was defined according to established adult criteria (LVDDadult; E/A < 1, E/e' > 14, or e'/a' < 0.8) and pediatric criteria (LVDDpeds; E/A <10th percentile, E/e' >99th percentile, or e'/a' <1st percentile) based on data from 103 age-sex matched healthy controls. Baseline factors associated with LVDDpeds were examined using Wilcoxon rank sum and χ2 tests. Multiple logistic regression analyses using generalized estimating equations to account for repeated measures evaluated the associations of adiposity and BP with LVDDpeds. RESULTS: The prevalence of LVDD ranged from 1.2% to 2.7% when we used adult criteria and 19% to 28% when we used pediatric criteria. Those with LVDDpeds were older, predominantly male, and non-African American and had greater weight, BP, BP medication use, and non-high-density lipoprotein cholesterol than those without LVDDpeds. Diastolic BP z score was associated with LVDDpeds by E/A (OR 1.95, 95% CI 1.15-3.32, P = .014) after we adjusted for age, sex, race, BP medications, and body mass index z score. CONCLUSIONS: LVDD was present in a substantial proportion of youth with overweight/obesity and elevated BP using pediatric criteria. Those with LVDDpeds had significantly greater measures of adiposity and BP compared with those without LVDDpeds, and diastolic BP z score was an independent predictor of LVDDpeds by E/A. These data emphasize the importance of prevention and treatment of cardiovascular disease risk factors in childhood.

Real-World Strategies to Treat Hypertension Associated with Pediatric Obesity.

PURPOSE OF REVIEW: To review the most recent literature on current strategies for the treatment of hypertension associated with pediatric obesity. RECENT FINDINGS: Over the last three decades, childhood and adolescent overweight and obesity prevalence in the USA has continued to rise. Unsurprisingly but rather disturbingly, this rising prevalence has been paralleled by an increase in cardiovascular disease (CVD) risk factors in childhood such as hypertension, dyslipidemia, and diabetes that become manifest earlier than previously reported. These childhood CVD risk factors are not only associated with target organ damage in childhood but also track into adulthood, increasing the risk of long-term CVD morbidity and mortality. There have been several mechanisms proposed to explain the role of obesity on the development of hypertension in childhood. However, central to the management of obesity-related hypertension is a multifaceted approach targeting lifestyle modifications and weight loss. Effective treatment often also requires a pharmacologic approach and rarely bariatric surgery.

A case of right aortic arch with isolated left innominate artery and global cerebral white matter atrophy.

A right aortic arch with an isolated left innominate artery is a rare form of aortic arch anomaly. We present a case of neonatal diagnosis of this anomaly with concerning findings of global cerebral white matter atrophy at 13 months of age.

Foetal right atrial aneurysm and aortic coarctation with left ventricular dysfunction.

Aneurysms of the right atrium are rare in the paediatric population. We report a case of a foetal diagnosis of right atrial aneurysm with associated atrial tachycardia in foetal and postnatal life. Unique to our case are the findings of isolated pericardial effusion without hydrops fetalis and the development of aortic coarctation in postnatal life.

Right ventricular longitudinal function is linked to left ventricular filling pressure in patients with repaired tetralogy of fallot.

Experimental data on pulmonary regurgitation has linked right ventricular longitudinal function to left ventricular filling pressure in animals with induced and treated pulmonary regurgitation but this relationship has not been investigated in patients with repaired Tetralogy of Fallot (rToF). The aim of this study was to determine if right ventricular longitudinal function assessed using cardiovascular magnetic resonance (CMR) is associated with left ventricular filling pressure in patients with rToF. A second objective of this study was to determine if direction of septal movement is related to right ventricular pressure load in rToF. Eighteen patients with rToF undergoing CMR and heart catheterization prior to pulmonary valve replacement were retrospectively included and catheter-based pressure measurements were compared with CMR-derived RV regional function. Left ventricular filling pressure was measured as precapillary wedge pressure (PCWP). Longitudinal contribution to RV stroke volume correlated with PCWP (r = 0.48; p = 0.046) but not with RV EF or pulmonary regurgitation. Neither RV longitudinal strain nor TAPSE showed correlation with PCWP. Longitudinal contribution to stroke volume was lower for the RV compared to the LV (49 vs 54%; p = 0.039). Direction of septal movement did not show a correlation with RV end-systolic pressure. Right ventricular longitudinal pumping is associated with left ventricular filling pressure in rToF-patients and this inter-ventricular coupling may explain LV underfilling in patients with pulmonary regurgitation and rToF and may be of value to determine right ventricular dysfunction. RV systolic pressure, however, cannot be assessed from the direction of septal movement, in these patients.