Background: Sickle cell disease (SCD) is the most common inherited blood disorder globally, affecting approximately 300,000 newborns annually. Cardiac remodeling, resulting from chronic anemia, vascular obstruction, and endothelial dysfunction, substantially contributes to morbidity and mortality in patients with SCD. Therefore, characterizing these patterns
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Background: Sickle cell disease (SCD) is the most common inherited blood disorder globally, affecting approximately 300,000 newborns annually. Cardiac remodeling, resulting from chronic anemia, vascular obstruction, and endothelial dysfunction, substantially contributes to morbidity and mortality in patients with SCD. Therefore, characterizing these patterns is essential to clinical management and outcome improvement in pediatric patients. However, a comprehensive synthesis of cardiac remodeling patterns in pediatric and adolescent patients with SCD and their associations with genotype and clinical severity is lacking.
Methods: We conducted a systematic review in accordance with the PRISMA 2020 guidelines and searched five databases for studies published from January 1978 to December 2024. Of 1131 retrieved studies, 37 met the inclusion criteria; of these, 31 focused exclusively on children (Group A), while six included both children and adults (Group B). We analyzed cardiac remodeling patterns, genotype-specific findings, associations with disease severity, and imaging modalities. The 37 studies included approximately 4253 patients from 12 countries, representing diverse populations and imaging techniques.
Results: Left ventricular (LV) dilation was the most frequently reported finding, noted in 33 of 37 studies (89.2%; representing study-level reporting frequency, not patient-level prevalence), followed by diastolic dysfunction (reported in 18 of 37 studies; 48.6%); elevated TRV (≥2.5 m/s) as an echocardiographic screening marker for pulmonary hypertension (PH) risk was found in 14 of 37 studies (37.8%; TRV ≥ 2.5 m/s is a screening criterion, not confirmed hemodynamic PH); myocardial fibrosis was found in three studies (8.1%, exclusively from mixed-age cohorts); and QTc prolongation/arrhythmia was found in one study (2.7%). The HbSS genotype was associated with the most severe cardiac changes. Studies that did not stratify by genotype subtype (HbS/β
0 vs. HbS/β
+) may underestimate cardiac severity in mixed-genotype cohorts. Markers of disease severity, such as elevated lactate dehydrogenase (LDH) expression, frequent acute chest syndrome (ACS), and increased hospitalizations, were associated with more pronounced cardiac remodeling in individual studies, but the cross-study consistency of this association varied. Study designs and imaging modalities also varied, underscoring the need for standardized assessment protocols to enhance comparability and clinical translation. This review presents a narrative synthesis; individual study statistics are reported as originally published, without formal pooled estimates.
Conclusions: Cardiac abnormalities in SCD were reported from early childhood, with more advanced phenotypes being more frequently described in older adolescents and mixed-age cohorts, suggesting possible age-related progression requiring prospective confirmation. Principal limitations include retrospective PROSPERO registration (CRD420261435382), the predominance of cross-sectional study designs, the inconsistent z-score normalization of cardiac dimensions, the incomplete reporting of treatment exposure, the disproportionate contribution of mixed-age cohorts to advanced imaging findings, and inter-study heterogeneity in echocardiographic protocols.
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