Sleep-Disordered Breathing in Patients with Pulmonary Valve Incompetence Complicating Congenital Heart Disease

Smooth muscle Cxcl12 contributions to vascular remodeling in flow and hypoxia-induced pulmonary hypertension

Patients with congenital heart disease (CHD) causing significant left-to-right shunting of blood are at risk of developing pulmonary arterial hypertension (PAH). However, the underlying mechanism by which pulmonary overcirculation and shear stress drive vascular remodeling remains poorly understood. Our study established a "two-hit" murine model of severe pulmonary hypertension (PH) by combining left pneumonectomy (LP) and chronic hypoxia (LP/Hx). Using transgenic reporter lines, immunofluorescence (IF) staining, and advanced microscopy, we conducted cell-lineage tracing for vascular cells, including smooth muscle cells (SMCs), endothelial cells (ECs), and pericytes. Our findings reveal that SMCs are key contributors to the distal arteriolar remodeling following LP and LP/Hx. PCR analysis of SMCs isolated from LP/Hx animals demonstrated upregulation of markers associated with contractility, proliferation, and Cxcl12 expression. Consistently, CXCL12 was found to be overexpressed in the SMC layer of pulmonary vessels from patients with PAH-CHD. Lastly, in vitro experiments with healthy human pulmonary artery SMCs showed that laminar shear stress induces CXCL12 upregulation. These findings provide novel insights into the role of SMCs in flow-induced vascular remodeling and their mechanosensitive response to shear stress. This murine model of severe PH is a valuable tool for future research and developing targeted therapeutics for patients with PAH.

Analysis of the causal factors of the nursing diagnosis of ineffective breathing pattern in children with congenital heart disease

PURPOSE

To analyze the causal factors of the nursing diagnosis of ineffective breathing pattern (IBP) in children with congenital heart disease.

METHODS

This was a cross-sectional study carried out in a tertiary hospital located in northeastern Brazil. Our sample was composed of 340 children with congenital heart disease. The latent class model with adjusted random effects determined the IBP. Univariate logistic regression analysis was performed for each IBP nursing diagnosis causal factor.

RESULTS

The analysis of etiological factors for the nursing diagnosis of IBP in children with congenital heart disease revealed a high prevalence of all causal factors investigated. The causal factors with the greatest impact on the occurrence of IBP were body position that inhibits pulmonary expansion; physical effort; pain; age less than two years; increased resistance to air passages; and reduced pulmonary compliance.

CONCLUSIONS

The occurrence of causal factors, body position that inhibits pulmonary expansion, physical effort, pain and age less than two years increases the chance of IBP nursing diagnosis in children with congenital heart disease.

IMPLICATIONS TO PRACTICE

The results obtained in this investigation can guide pediatric nurses in making diagnostic decisions, as identifying the causal factors that trigger or potentiate IBP in children with congenital heart disease allows nurses to intervene early, facilitating the maintenance of breathing patterns.

Empirical Testing of a Middle-Range Theory for Ineffective Breathing Pattern in Children With Congenital Heart Disease

AIM

To test a middle-range theory (MRT) for the nursing diagnosis of ineffective breathing pattern in children with congenital heart disease (CHD) based on analysis of two general propositions.

METHODS

This cross-sectional study is guided by STROBE. The propositions represent hypotheses about the relationships between the concepts of this MRT to be tested empirically, and thus, log-linear models were used to verify the structure of the proposition related to the stimuli. Diagnostic accuracy measures, univariate logistic regressions and the Mann-Whitney test were used to analyse the structure of the propositions related to behaviours.

RESULTS

The analysis of the propositions related to the stimuli (eight concepts, four of which were classified as focal stimuli and four as contextual stimuli) suggested a reclassification of the stimulus "deformities in the thoracic wall" which became too focal. In the analysis of the propositions related to behaviours (17 concepts, five of which were classified as acute confirmatory, nine as acute clinical deterioration and three classified as chronic), guided changes in the operationalisation of concepts were suggested after comparing clinical findings; thus, acute confirmatory behaviours now have 10 concepts, while acute clinical deterioration behaviours and chronic behaviours continued with nine and three concepts, respectively, but with reclassifications between them.

CONCLUSION

Changes in the operationalisation of the classification of the elements of the two propositions occurred after comparing the clinical findings with the theoretical model.

RELEVANCE TO CLINICAL PRACTICE

By establishing precise causal relationships and describing how IBP manifests itself over time in children with CHD, empirical testing of this MRT helps nurses understand clinical reasoning based on temporal logic and spectral interaction between diagnostic components, which in turn will improve the use and accuracy of nursing diagnoses.

PATIENT CONTRIBUTION

Children and adolescents with CHD were recruited for this study sharing their clinical history and physical lung examination.

Smooth muscle Cxcl12 activation is associated with vascular remodeling in flow-induced pulmonary hypertension

Patients with congenital heart disease (CHD) resulting in significant left-to-right shunting of blood are at risk for the development of pulmonary arterial hypertension (PAH). The underlying mechanism by which pulmonary overcirculation and shear stress lead to vascular remodeling remains unclear. Our study established a new "two-hit" murine model of severe pulmonary hypertension (PH) by combining left pneumonectomy and exposure to hypoxia (LP/Hx). Utilizing transgenic reporter lines, immunofluorescence staining, and advanced microscopy, we conducted cell-lineage tracing experiments for endothelial cells (ECs), smooth muscle cells (SMCs), and pericytes. We identified that SMCs is a primary contributor to distal arteriolar remodeling after LP/Hx. Subsequent qPCR analysis on isolated cells demonstrated that Cxcl12 was upregulated in both ECs and SMCs from LP/Hx animals. Likewise, CXCL12 was overexpressed in the SMC layer of arterioles in patients with acyanotic PAH-CHD. These findings provide novel insights into the contribution of SMCs and Cxcl12 to pulmonary flow-induced vascular remodeling. This newly established murine model of PH will serve as a new tool for research and targeted therapeutics for patients with PAH.

Sleep-disordered breathing and lung function abnormalities in adults with congenital heart disease

PURPOSE

Advances in treatment enables most patients with congenital heart diseases (CHD) to survive into adulthood, implying the need to address comorbid conditions in this growing cohort of patients. The aim of this study was to evaluate the prevalence of sleep-disordered breathing (SDB) and lung function abnormalities in patients with adult congenital heart disease (ACHD).

METHODS

Patients with ACHD underwent level 3 sleep testing (Embletta MPR polygraphy) and pulmonary function testing. Results were stratified by the underlying haemodynamic ACHD lesion group.

RESULTS

Patients with ACHD (n = 100) were middle-aged (42.3 ± 14.6 years), 54% male and slightly overweight (BMI 25.9 ± 5.5 kg/m2). Polygraphy revealed a prevalence of sleep apnoea of 39% with 15% of patients presenting with predominantly obstructive apnoeic episodes, while 23% of patients presenting primarily with central sleep apnoea. The distribution of mild, moderate, and severe sleep apnoea in the total study population was 26%, 7% and 6%, respectively. Comparison of apnoea-hypopnoea index, presence of sleep apnoea, and apnoea severity did not offer significant differences between the four ACHD lesion groups (p = 0.29, p = 0.41 and p = 0.18, respectively). Pulmonary function testing revealed obstructive lung disease in 19 of 100 patients. Concomitant chronic obstructive pulmonary disease and obstructive sleep apnoea were diagnosed in 3% of patients and were associated with profound nocturnal desaturation.

CONCLUSION

The findings suggest a mild propensity amongst patients with ACHD to develop SDB that seems to be unaffected by the specific underlying congenital lesion.

Content validity of the nursing diagnostic Breathing Pattern, Ineffective, in children with congenital heart defects

OBJECTIVE

To estimate the content validity of the nursing diagnostic Breathing Pattern, Ineffective, in children with congenital heart defects.

METHOD

Methodological study in two stages: 1) integrative literature review; 2) content validation, with 23 nurses. An instrument with 10 related factors and 21 defining characteristics for data collection was used. The analysis by the evaluators was carried out using the relevance criteria. The Content Validity Index was used. Valid results were those above 0.9 with a Wilcoxon test above 0.05.

RESULTS

The final proposal incorporates nine from the ten causal factors. From them, five do not belong in the NANDA-I list. Regarding the defining characteristics, they were all considered to be relevant, and five are not among the list of signs and symptoms of the NANDA-I taxonomy.

CONCLUSION

The findings of this study include specific elements of the pediatric population with congenital heart defect which are not present in the structure of the diagnostic being studied.

Heart failure in adult congenital heart disease: tetralogy of Fallot

The number of rTOF patients who survive into adulthood is steadily rising, with currently more than 90% reaching the third decade of life. However, rTOF patients are not cured, but rather have a lifelong increased risk for cardiac and non-cardiac complications. Heart failure is recognized as a significant complication. Its occurrence is strongly associated with adverse outcome. Unfortunately, conventional concepts of heart failure may not be directly applicable in this patient group. This article presents a review of the current knowledge on HF in rTOF patients, including incidence and prevalence, the most common mechanisms of heart failure, i.e., valvular pathologies, shunt lesions, left atrial hypertension, primary left heart and right heart failure, arrhythmias, and coronary artery disease. In addition, we will review information regarding extracardiac complications, risk factors for the development of heart failure, clinical impact and prognosis, and assessment possibilities, particularly of the right ventricle, as well as management strategies. We explore potential future concepts that may stimulate further research into this field.

Prevalence, Risk Factors, and Impact of Obstructive Sleep Apnea in Adults with Congenital Heart Disease

The objective of our study was to determine the prevalence, risk factors, and the impact of obstructive sleep apnea (OSA) in the adult with congenital heart disease (ACHD). One hundred forty-nine consecutive patients seen in our ACHD program were screened for OSA using the Berlin Questionnaire. Demographic and clinical details on subjects were collected through a chart review. Clinical variables were analyzed to determine risk factors for positive OSA screen, as well as associated outcomes. Seventy-seven (52%) of our cohort were females. The median age of the cohort was 33 years (range = 18-74) and median weight was 79 kg (range = 50-145 kg). Overall, 47 (31%) of our cohort were found to have a positive OSA screen using the Berlin questionnaire. Median age of the patients whom tested positive was 34 years. Compared to patients with a negative screen, patients with a positive OSA screen were more likely to be heavier with a median weight of 99 kg vs 71 kg (p < 0.01) and a larger BMI (31 vs 25 kg/m², p < 0.01). Overall, 55% of patients whom screened positive were obese (defined as a BMI > 30) compared to 15% in the negative group (p < 0.02). Patients with a positive screen were more likely to have other co-morbidities including diabetes (p < 0.04), hypertension (p < 0.05), depression (p < 0.002), and were more likely to have decreased exercise capacity (p < 0.01) and a defibrillator (p < 0.007). Our data demonstrates that OSA is common in the ACHD patient and is associated with increasing weight and BMI. Patients with a positive screen are at increased risk for multiple co morbidities including diabetes, hypertension, and depression. We believe our data supports the use of screening protocols for OSA in the ACHD population in effort to identify early, treat, and potentially prevent late complications.

OSA and Neurocognitive Impairment in Children With Congenital Heart Disease

BACKGROUND

Children with congenital heart disease (CHD) have an increased risk of neurocognitive impairment. No prior studies have evaluated the role of OSA, which is associated with neurocognitive impairment in children without CHD.

RESEARCH QUESTION

Is OSA is associated with neurocognitive impairment in children with CHD?

STUDY DESIGN AND METHODS

Children aged 6 to 17 years with corrected moderate to complex CHD without syndromes that may affect neurocognition were recruited from the pediatric cardiology clinic. Participants underwent home sleep testing and neurocognitive testing, including a validated Intellectual Quotient (IQ) test as well as validated tests of memory (Paired Associates Learning test), executive function (Intra-Extra Dimensional set shift test), and attention (Simple Reaction Test) from the CANTAB neurocognitive testing battery.

RESULTS

Complete results were available for 30 children. Seventeen children (57%) were found to have OSA. Total IQ was markedly lower in children with CHD and comorbid OSA compared with children with CHD without comorbid OSA (mean, 86 ± 12 vs 98 ± 11; P = .01). Children with CHD and OSA did significantly worse on the Paired Associates Learning test, with a median of eight total errors (interquartile range [IQR], 2.25-15) compared with children with CHD without OSA (median total errors, 2, IQR, 1-8; P = .02).

INTERPRETATION

Children with CHD and comorbid OSA have impaired neurocognition compared with children with CHD without comorbid OSA. OSA may be a reversible cause of neurocognitive impairment in children with CHD. Further research is needed to evaluate the effects of OSA treatment on neurocognitive impairment in children with CHD.

Home Oxygen Therapy for Children. An Official American Thoracic Society Clinical Practice Guideline

Background: Home oxygen therapy is often required in children with chronic respiratory conditions. This document provides an evidence-based clinical practice guideline on the implementation, monitoring, and discontinuation of home oxygen therapy for the pediatric population.

Methods: A multidisciplinary panel identified pertinent questions regarding home oxygen therapy in children, conducted systematic reviews of the relevant literature, and applied the Grading of Recommendations, Assessment, Development, and Evaluation approach to rate the quality of evidence and strength of clinical recommendations.

Results: After considering the panel’s confidence in the estimated effects, the balance of desirable (benefits) and undesirable (harms and burdens) consequences of treatment, patient values and preferences, cost, and feasibility, recommendations were developed for or against home oxygen therapy specific to pediatric lung and pulmonary vascular diseases.

Conclusions: Although home oxygen therapy is commonly required in the care of children, there is a striking lack of empirical evidence regarding implementation, monitoring, and discontinuation of supplemental oxygen therapy. The panel formulated and provided the rationale for clinical recommendations for home oxygen therapy based on scant empirical evidence, expert opinion, and clinical experience to aid clinicians in the management of these complex pediatric patients and identified important areas for future research.

Impact of Non-cardiac Comorbidities in Adults with Congenital Heart Disease: Management of Multisystem Complications

The prevalence and impact of non-cardiac comorbidities in adult patients with congenital heart disease increase over time, and these complications are often specifically a consequence of the long-term altered cardiovascular physiology or sequelae of previous therapies. For the ACHD patient admitted to the intensive care unit (ICU) for either surgical or medical treatment, an assessment of the burden of multisystem disease, as well as an understanding of the underlying cardiovascular pathophysiology, is essential for optimal management of these complex patients. This chapter takes an organ-system-based approach to reviewing common comorbidities in the ACHD patient, focusing on conditions that are directly related to ACHD status and may significantly impact ICU care.