Longitudinal Analysis of Echocardiographic Abnormalities in Children With Sickle Cell Disease

Atrial arrhythmia in adults with sickle cell anemia: a missing link toward understanding and preventing strokes

ABSTRACT

Although patients with homozygous sickle cell anemia (SCA) carry both significant left atrial (LA) remodeling and an increased risk of stroke, the prevalence of atrial arrhythmia (AA) has never been prospectively evaluated. The aim of this study was to identify the prevalence and predictors of atrial arrhythmia in SCA. From 2018 to 2022, consecutive adult patients with SCA were included in the DREPACOEUR prospective registry and referred to the physiology department for cardiac evaluation, including a 24-hour electrocardiogram monitoring (ECG-Holter). The primary endpoint was the occurrence of AA, defined by the presence of excessive supraventricular ectopic activity (ESVEA) on ECG-Holter (ie >720 premature atrial contractions [PACs] or any run ≥ 20 PACs) or any recent history of atrial fibrillation. Overall, 130 patients with SCA (mean age: 45±12 years, 48% of male) were included. AA was found in 34 (26%) patients. Age (52±9 vs. 42±12 years, P=0,002), LA dilation (LAVi, 71±24 vs. 52±14 mL/m², P<0.001) and history of stroke without underlying cerebral vasculopathy (26% vs. 5%, P=0.009, OR=6.6 (95%CI 1.4-30.3]) were independently associated with AA. Age and LAVi correlated with PAC load per 24 hours on ECG-Holter. An age over 47 years or a LAVi >55mL/m² could predict AA with a PPV of 33% and a NPV of 92%. AAs are frequent in middle-aged patients with SCA and increase with age and LA remodeling, leading to a major additional risk factor for ischemic stroke. This study provides arguments and means to early screen for AA and potentially prevent cerebral complications.

Assessment of Biventricular Systolic and Diastolic Function Using Conventional and Strain Echocardiography in Children with Sickle Cell Disease Surviving 1-year After Hematopoietic Stem Cell Transplant

Hematopoietic stem cell transplant (HSCT) is a potentially curative therapy for children with sickle cell disease (SCD). The effects of HSCT on ventricular function are not well characterized in children with SCD. Echocardiograms from children with SCD who underwent HSCT between 2007 and 2017 were retrospectively analyzed before and 1-year after HSCT. Left ventricular (LV) volumes, mass, and ejection fraction were calculated by the 5/6 area*length method. LV end-diastolic and systolic dimensions, septal, and posterior wall thickness, and fractional shortening were measured by M-mode. Mitral and tricuspid inflow Dopplers (E and A waves) as well as mitral, tricuspid, and septal tissue Dopplers (E', A') were assessed. E/A, E'/A' and E/E' ratios were calculated. Biventricular strain imaging was performed using speckle-tracking echocardiography. Peak global systolic longitudinal and circumferential LV strain, and global longitudinal right ventricular strain, as well as early and late diastolic strain rate, were measured on LV apical 4-chamber, LV short-axis mid-papillary, and RV apical views, respectively. Forty-seven children (9.7 ± 5.5 years, 60% male) met inclusion criteria. Pre-HSCT, subjects had mild LV dilation with normal LV systolic function by conventional measure of ejection fraction and fractional shortening. There was a significant reduction in LV volume, mass, and ejection fraction after HSCT, but measurements remained within normal range. LV longitudinal and circumferential strain were normal pre-HSCT and showed no significant change post-HSCT. RV strain decreased after HSCT, but the absolute change was small, and mean values were normal both pre- and post-HSCT. Conventional measures of diastolic function were all normal pre-HSCT. Post-HSCT there was a reduction in select parameters, but all parameters remained within normal range. Early and late diastolic strain rate parameters showed no significant change from pre- to post-HSCT. At one-year after HSCT in children with SCD conventional measures of systolic and diastolic function are within normal limits. Except for a small decrease in RV systolic strain with values remaining within normal limits, systolic strain and diastolic strain rate values did not significantly change 1-year after HSCT.

Prevalence of Cardiovascular Complications in Individuals with Sickle Cell Anemia and Other Hemoglobinopathies: A Systematic Review

BACKGROUND

Sickle cell anemia (SCA) is a hereditary disease whose cardiovascular complications are the main cause of death, the same being observed in other hemoglobinopathies. Early identification of these changes can favorably modify the course of the disease.

OBJECTIVE

To compare the prevalence of cardiovascular complications between individuals with SCA and individuals with other hemoglobinopathies.

METHOD

Following the recommendations of the PRISMA protocol, a systematic literature review was carried out with searches in PubMed/Medline databases, associated with a manual search. Studies that analyzed the prevalence of cardiovascular alterations in hemoglobinopathies (SCA, sickle cell trait, SC hemoglobinopathy, alpha-thalassemia and beta-thalassemia) were included. The methodological quality of the articles was assessed using the Newcastle-Ottawa scale.

RESULTS

Four studies were selected for analysis, resulting in a sample size of 582 participants: 289 with SCA, 133 with SC hemoglobinopathy, 40 with beta-thalassemia, 100 healthy individuals and none with alpha-thalassemia or sickle cell trait. Dilatation of the cardiac chambers, left and right ventricular hypertrophy, pulmonary hypertension, diastolic dysfunction, mitral regurgitation and tricuspid regurgitation are more prevalent in SCA than in the other hemoglobinopathies considered. Myocardial iron overload is more frequent in thalassemia major than in sickle cell anemia. Systolic function is similar between different hemoglobinopathies.

CONCLUSION

There is greater cardiovascular impairment in individuals with SCA than in those with other hemoglobinopathies, reinforcing the necessity for regular cardiovascular follow-up in sickle cell patients.

Longitudinal Changes in Cardiac Function Based on Serial Tissue Doppler and Doppler Imaging for Patients With Sickle Cell Anemia

Objective:

The aim was to evaluate the long-term changes in systolic and diastolic functions with tissue Doppler imaging in children with sickle cell anemia.

Materials and Methods:

In this study, myocardial performance index of ventricles and mitral and tricuspid valve E/A ratios were calculated. Wall motion velocities of the interventricular septum, right and left ventricles, and mitral and tricuspid annulus were assessed during the systole (Sm), the early diastole (Em), and the late diastole (Am) with pulsed Doppler echocardiography.

Results:

These diagnostic parameters were obtained from 38 patients (mean 12.5 ± 3.2 years old) who were reached after a mean 6.7 years in long-term follow-up. Left ventricular and septal end-systolic and end-diastolic diameters, and right and left ventricular myocardial performance index were higher in patients ( P < .05 and P = .001, respectively). The Em, Am, and Sm velocities of the right ventricle and septum were significantly lower in the patients at the baseline measures ( P < .05) and all these velocities decreased significantly in patients over time compared with their baseline values ( P < .05). In addition, it was observed that myocardial performance index values of the right and left ventricles increased significantly over time ( P < .05).

Conclusion:

This is the first study reflecting the age-related changes in global systolic and diastolic functions in sickle cell anemia by serial imaging.

Stable to improved cardiac and pulmonary function in children with high-risk sickle cell disease following haploidentical stem cell transplantation

Children with sickle cell disease (SCD) are at high-risk of progressive, chronic pulmonary and cardiac dysfunction. In this prospective multicenter Phase II trial of myeloimmunoablative conditioning followed by haploidentical stem cell transplantation in children with high-risk SCD, 19 patients, 2.0-21.0 years of age, were enrolled with one or more of the following: history of (1) overt stroke; (2) silent stroke; (3) elevated transcranial Doppler velocity; (4) multiple vaso-occlusive crises; and/or (5) two or more acute chest syndromes and received haploidentical transplants from 18 parental donors. Cardiac and pulmonary centralized cores were established. Pulmonary function results were expressed as percent of the median of healthy reference cohorts, matched for age, sex, height and race. At 2 years, pulmonary functions including forced expiratory volume (FEV), FEV₁/ forced vital capacity (FVC), total lung capacity (TLC), diffusing capacity of lung for carbon monoxide (DLCO) were stable to improved compared to baseline values. Importantly, specific airway conductance was significantly improved at 2 years (p < 0.004). Left ventricular systolic function (fractional shortening) and tricuspid regurgitant velocity were stable at 2 years. These results demonstrate that haploidentical stem cell transplantation can stabilize or improve cardiopulmonary function in patients with SCD.

Cardiovascular manifestations of sickle cell disease

Sickle cell disease (SCD) is the most frequent genetic haemoglobinopathy worldwide. Early childhood mortality has dramatically decreased in high-income countries, and most patients now survive beyond the 5th decade. However, in the aging SCD population, the morbidity related to chronic organ damage, especially kidney and heart, has become a major concern. While pulmonary hypertension has attracted most attention, it appears that this condition is frequently linked to left heart failure (HF). Accordingly, SCD-associated cardiomyopathy is emerging as a major cause of reduced quality of life and early mortality in these patients. The diagnosis of this particular phenotype of high-output HF is challenging. Exercise intolerance and dyspnoea in SCD patients are linked to multiple causes including chronic anaemia. Moreover, echocardiographic features are unusual and can be misinterpreted. The classical diagnosis algorithm for HF is generally not suitable in SCD patients, and HF is poorly recognized and mostly diagnosed at a late congestive stage in routine practice. Such patients need to be identified at an earlier stage of myocardial dysfunction via improved phenotyping. This constitutes the first step towards further investigations in SCD needed to improve the prognosis and the quality of life. This article provides an updated review of the recent advances in the pathophysiology and diagnosis, and in addition, perspectives of new therapeutic approaches in SCD-related cardiac manifestations.

The association of nocturnal hypoxia and an echocardiographic measure of pulmonary hypertension in children with sickle cell disease

BACKGROUND

Pulmonary hypertension (PH) is multifactorial in origin and may develop early in children with sickle cell disease (C-SCD). Potential etiologies are hemolysis-induced endothelial dysfunction, left ventricular (LV) dysfunction, and chronic hypoxia. Nocturnal hypoxia (NH) in C-SCD is known to be a sequela of obstructive sleep apnea (OSA). The primary objective of this study is to correlate polysomnographic evidence NH with echocardiographic measures of PH in C-SCD.

METHODS

We performed a retrospective chart review of 20 C-SCD (Hemoglobin SS), who had polysomnography and echocardiogram performed within a narrow time interval, and 31% of them had pre-existing cardiac conditions. Tricuspid regurgitant jet velocity (TRJV) ≥ 2.5 m/s was considered as an indicator of PH.

RESULTS

Twenty-five percent of the subjects had NH. Forty percent of C-SCD, predominantly male, had evidence of PH based on an elevated TRJV. Children with NH compared to non-NH had significantly worse baseline hypoxemia (p < 0.001), higher TRJV (p = 0.005), and higher LV end-diastolic diameters (p = 0.009). The severity of NH was influenced by OSA. However, PH was not associated with OSA or duration of hydroxyurea therapy.

CONCLUSION

Our study indicates that NH is associated with PH in C-SCD, and that screening for NH may help to identify C-SCD with higher morbidity risk.