Echocardiography for the Assessment of Pulmonary Hypertension and Congenital Heart Disease in the Young

Prevalence of pulmonary hypertension in children with obstructive sleep apnea living at high altitude

Introduction

The prevalence of obstructive sleep apnea (OSA) is 1-4 %. Some reports describe its association with pulmonary hypertension (PH), but its prevalence is unknown. No studies at high altitude have determined the relationship between OSA and PH. The aim of this study was to establish the prevalence of PH in children diagnosed with OSA living in a high-altitude city at 2640 m above sea level.

Methods

Children between 2 and 16 years of age referred to the Sleep Laboratory of the Fundación Neumológica Colombiana in Bogotá with a positive polysomnogram for OSA were included, and a two-dimensional transthoracic echocardiogram (TTE) was performed to evaluate PH. Statistical analysis was performed using median, interquartile range, chi-squared test, and Kruskall-Wallis test.

Results

Of the 55 patients (n: 55), 63.6 % were male, with a median age of 6 years, 14 children (25.5 %) were overweight; 12 children (21.8 %) had mild OSA, 12 (21.8 %) had moderate OSA and 31 (56.4 %) severe OSA. In patients with severe OSA, the minimum saturation during events was 78 % with a desaturation index (DI) of 33.8/hour (p < 0.01). T90 and T85 increased proportionally with OSA severity (p < 0.05). Of the 55 patients with OSA, none had PH according to echocardiography; 4 patients (7.2 %) had pulmonary artery systolic pressure (PASP) at the upper limit of normal (ULN), and it was not related to a higher body mass index (BMI).

Conclusions

We found no association between OSA and PH in children with OSA at high altitude.

Meta-analysis of the correlation between pulmonary hypertension and echocardiographic parameters in patients with chronic kidney disease

Objective

To investigate the correlation between pulmonary hypertension (PH) and echocardiographic parameters in patients with chronic kidney disease (CKD).

Methods

PubMed, Embase, Web of Science, Cochrane, VIP, CNKI, and Wanfang databases were systematically searched for articles published from inception to 19 May 2023. Study quality was estimated using the Quality Assessment of Case-Control Studies tool. Forest plots were drawn using R language software. The "metacor" function in the "meta" package was utilized for meta-analysis of the r-values and their standard errors. Heterogeneity and sensitivity analyses were carried out, with the main outcomes as r-value, p-value, and I2 value.

Results

Eleven studies were included, with 1,809 CKD patients. The correlations between 12 echocardiographic parameters and PH were analyzed. Except for FS and LVEF which were negatively correlated with CKD-PH, the other 10 parameters were positively correlated with CKD-PH. Among them, LA was highly correlated with CKD-PH (0.70 < r < 0.89); LVDD, RA, RV, LVMI, and LVDS were moderately correlated with CKD-PH (0.40 < r < 0.69); while PA, IVS, LVPW, SV, FS, and LVEF were lowly correlated with CKD-PH (0.20 < r < 0.39). The synthesized estimates were stable against heterogeneity.

Conclusion

CKD-PH patients may have large cardiac chambers, thickened septal tissue on both sides of the chambers, reduced pulmonary artery flow rates, and decreased left ventricular function.

Predictive value of red cell distribution width in children with pulmonary arterial hypertension associated with CHD

BACKGROUND

Pulmonary arterial hypertension, a common consequence of untreated CHD, is associated with a significant morbidity and mortality. Recent researches have demonstrated that patients with clinically severe cardiovascular illnesses, including pulmonary hypertension, have a greater mortality risk when their red cell distribution width is high. This work aimed to assess the predictive value of red cell distribution width in children with pulmonary arterial hypertension-CHD and to correlate red cell distribution width with various clinical and echocardiographic data.

SUBJECTS AND METHODS

Sixty patients with CHD associated with pulmonary arterial hypertension were enrolled as the patient group. Another 60 patients with CHD and no pulmonary arterial hypertension, matched for age and sex, were enrolled as the control group. Electrocardiography and echocardiographic evaluation were performed for all included children. Red cell distribution width as part of the complete blood count was also performed using a Coulter® LH 700 series haematology analyzer.

RESULTS

The red cell distribution width was significantly higher in the pulmonary arterial hypertension-CHD group than in the CHD-only group (P < 0.05). There was a significant positive correlation between the red cell distribution width and mean pulmonary artery pressure. Red cell distribution width was an independent predictor of mortality in children with pulmonary arterial hypertension-CHD. The best red cell distribution width cut-off for predicting mortality in children with pulmonary arterial hypertension-CHD was ≥ 17.6%.

CONCLUSION

Red cell distribution width was significantly higher in children with pulmonary arterial hypertension-CHD than in those without pulmonary arterial hypertension. Moreover, red cell distribution width could be a cheap easy predictive marker for mortality in children with pulmonary arterial hypertension-CHD.

Lung ultrasound in the evaluation of pulmonary edema in newborns with critical congenital heart disease

BACKGROUND

Newborns with critical congenital heart disease (CCHD) with increased pulmonary blood flow (PBF) are at high risk for congestive heart failure. In this study, we aimed to evaluate the presence and degree of pulmonary edema in newborns with CCHD using lung ultrasound (LUS) during the perioperative period.

METHODS

Prospective clinical trial, 44 newborn patients with CCHD were evaluated in this prospective clinical trial. LUS was repeatedly performed to determine the course of pulmonary edema during the perioperative period. LUS was performed simultaneously with chest radiography (CXR), which was the main part of patient management. The primary outcome of this study was to identify whether a correlation existed between LUS and CXR findings. The secondary outcomes were to determine the relationship between LUS and the need for respiratory support, diuretic use, vasoactive inotropic score (VIS), and pro-B-type natriuretic peptide (pro-BNP) levels during the perioperative period.

RESULTS

The mean gestational age of the patients was 38.3 ± 1.7 weeks, with a mean birth weight of 3026 ± 432 g. In the preoperative period, both LUS and CXR images were consistent with clinical signs of pulmonary edema. On the first postoperative day, pulmonary edema increased compared to the preoperative period but gradually decreased by the 6th day of surgery (p < 0.05). Positive correlations were observed between the LUS and CXR findings at all study points (p < 0.05). The LUS findings exhibited trends parallel to those of VIS, serum pro-BNP levels, need for respiratory support, and diuretic requirements. As expected, these trends were more pronounced in CCHDs where PBF increased.

CONCLUSION

In CCHD, serial lung ultrasound (LUS) assessments, particularly in cases with increased PBF, can provide valuable guidance for managing patients during the perioperative period.

Safety and Efficacy of Sildenafil for Group 2 Pulmonary Hypertension in Left Heart Failure

Pulmonary hypertension (PH) is a multifactorial, progressive disease with poor outcomes. Group 2 PH is defined by pulmonary vascular disease with elevated pulmonary capillary wedge pressure including both left-sided obstructive lesions and diastolic heart failure (HF). Sildenafil was historically discouraged in this population as pulmonary vasodilation can lead to pulmonary edema. However, evidence suggests that sildenafil can help to treat the precapillary component of PH. This is a single center, retrospective pilot study of pediatric PH patients with left-sided HF who were treated with sildenafil for ≥ 4 weeks. HF patients without mechanical support (HF group) and HF patients with a left ventricular assist device (HF-VAD) were analyzed. The exploratory analysis described the safety and side effects of the drug. Echocardiographic parameters were compared before and after sildenafil treatment in a paired analysis. The changes in medical therapy during treatment, mechanical support, and mortality was reported; 19/22 patients tolerated sildenafil. Pulmonary edema in two patients resolved upon discontinuation of sildenafil. In the HF group, both the right atrial volume and right ventricular diastolic area decreased, and the tricuspid regurgitation (TR) S/D ratio decreased after therapy (p = 0.02). Across both the groups, four patients weaned off milrinone and seven weaned off inhaled nitric oxide. Of the thirteen HF patients, four received a transplant, and all of the nine HF-VAD patients received a transplant. Sildenafil can be safely used in carefully selected patients with HF and mixed pre/postcapillary PH with judicious titration and inpatient surveillance, with patients showing improvements in echocardiographic parameters.

Identification of SOX18 as a New Gene Predisposing to Congenital Heart Disease

Congenital heart disease (CHD) is the most frequent kind of birth deformity in human beings and the leading cause of neonatal mortality worldwide. Although genetic etiologies encompassing aneuploidy, copy number variations, and mutations in over 100 genes have been uncovered to be involved in the pathogenesis of CHD, the genetic components predisposing to CHD in most cases remain unclear. We recruited a family with CHD from the Chinese Han population in the present investigation. Through whole-exome sequencing analysis of selected family members, a new SOX18 variation, namely NM_018419.3:c.349A>T; p.(Lys117*), was identified and confirmed to co-segregate with the CHD phenotype in the entire family by Sanger sequencing analysis. The heterozygous variant was absent from the 384 healthy volunteers enlisted as control individuals. Functional exploration via luciferase reporter analysis in cultivated HeLa cells revealed that Lys117*-mutant SOX18 lost transactivation on its target genes NR2F2 and GATA4, two genes responsible for CHD. Moreover, the genetic variation terminated the synergistic activation between SOX18 and NKX2.5, another gene accountable for CHD. The findings strongly indicate SOX18 as a novel gene contributing to CHD, which helps address challenges in the clinical genetic diagnosis and prenatal prophylaxis of CHD.

Normal Echocardiographic Reference Values of the Right Ventricular to Left Ventricular Endsystolic Diameter Ratio and the Left Ventricular Endsystolic Eccentricity Index in Healthy Children and in Children With Pulmonary Hypertension

Background

An accurate assessment of the right and left ventricle and their interaction is important in pediatric pulmonary hypertension (PH). Our objective was to provide normal reference values for the right ventricular to left ventricular endsystolic (RV/LVes) ratio and the LV endsystolic eccentricity index (LVes EI) in healthy children and in children with PH.

Methods

We conducted an echocardiographic study in 769 healthy children (median age: 3.36 years; range: 1 day—18 years) and validated abnormal values in 44 children with PH (median age: 2.1 years; range: 0.1 months—17.7 years). We determined the effects of gender, age, body length, body weight, and body surface area (BSA) on RV/LVes ratio and LVes EI values. The RV/LVes ratio and LVes EI were measured from the parasternal short axis view between papillary muscle from the endocardial to endocardial surfaces.

Results

Both, the RV/LVes ratio and the LVes EI were highly age-dependent: (i) neonates RV/LVes ratio [median 0.83 (range 0.53–1.37)], LVes EI [1.21 (0.92–1.45)]; (ii) 12–24 months old: RV/LVes ratio: [0.55 (0.35–0.80)], LVes EI: [1.0 (0.88–1.13)]; iii) 18th year of life RV/LVes ratio: [0.53 (0.32–0.74)], LVes EI: [1.0 (0.97–1.07)]. Healthy neonates had high LVes EI and RV/LVes ratios, both gradually decreased within the first year of life and until BSA values of about 0.5 m2, body weight to about 15 kg and body length to about 75 cm, but were almost constant thereafter. Children (&gt;1 year) and adolescents with PH had significantly higher RV/LVes ratio (no PH: median 0.55, IQR 0.49–0.60; PH: 1.02, 0.87–1.26; p &lt; 0.001) and higher LVes EI values (no PH: 1.00, 0.98–1.00; PH: 1.53, 1.26–1.71; p &lt; 0.001) compared to those without PH. To predict the presence of PH in children &gt; 1 year, we found the following best cutoff values: RV/LVes ratio ≥ 0.67 (sensitivity: 1.00, specificity: 0.95) and LVes EI ≥ 1.06 (sensitivity: 1.00, specificity: 0.97).

Conclusion

We provide normal echocardiographic reference values of the RV/LVes ratio and LVes EI in healthy children, as well as statistically determined cutoffs for the increased values in children with PH.

A guide to echocardiographic assessment in children and adolescents with pulmonary hypertension

While the current definition of pulmonary hypertension (PH) is still based on haemodynamic variables, transthoracic echocardiography is the most important diagnostic clinical tool for the first assessment and evaluation of a patient, in whom PH is suspected. In addition, it is the most important clinical modality in long term follow-up and the utility of echocardiography has widely been demonstrated in patients with PH. Echocardiography not only reveals the underlying cardiac morphology and diagnosis of any associated cardiac defects. In most patients with PH right ventricular (RV) pressure estimation is feasible. In addition, ventricular systolic and diastolic function, as well as ventricular-ventricular interactions of both ventricles can be assessed by using echocardiography. Maximizing the use of echocardiography by reporting several measures to gain information and quantitatively describe the parameters, that are linked to prognosis, seem particularly appealing in these children, in whom other advanced imaging modalities requiring anaesthesia is associated with a considerable risk. Herein we provide a practical approach and a concise and clinically applicable echocardiographic guidance and present basic variables, which should be obtained at any assessment. Moreover, we present additional advanced echocardiographic measures, that can be applied in a research or clinical setting when progressive PH needs a deeper insight to assess heart function, estimation of pulmonary artery pressures among others, by echocardiography. Finally, clinically relevant studies in view of the prognostic properties with a focus on the most important echocardiographic variables in pediatric PH are summarized.