Determinants of ventricular arrhythmias in sickle cell anemia: toward better prevention of sudden cardiac death.

Sudden death is 1 of the leading causes of death in adults with sickle cell anemia (SCA) but its etiology remains mostly unknown. Ventricular arrhythmia (VA) carries an increased risk of sudden death; however, its prevalence and determinants in SCA are poorly studied. This study aimed to identify the prevalence and predictors of VA in patients with SCA. From 2019 to 2022, 100 patients with SCA were referred to the physiology department to specifically analyze cardiac function and prospectively included in the DREPACOEUR registry. They underwent a 24-hour electrocardiogram monitoring (24h-Holter), transthoracic echocardiography, and laboratory tests on the same day. The primary end point was the occurrence of VA, defined as sustained or nonsustained ventricular tachycardia (VT), >500 premature ventricular contractions (PVCs) on 24h-Holter, or a recent history of VT ablation. The mean patient age was 46 ± 13 years, and 48% of the patients were male. Overall, VA was observed in 22 (22%) patients. Male sex (81% vs 34%; P = .02), impaired global longitudinal strain (GLS): -16% ± 1.9% vs -18.3% ± 2.7%; P = .02), and decreased platelet count (226 ± 96 giga per liter [G/L] vs 316 ± 130 G/L) were independently associated with VA. GLS correlated with PVC load every 24 hours (r = 0.39; P < .001) and a cutoff of -17.5% could predict VA with a sensitivity of 82% and a specificity of 63%. VAs are common in patients with SCA, especially in men. This pilot study uncovered GLS as a valuable parameter for improving rhythmic risk stratification.

Fetal Hemoglobin Decrease During Voxelotor Treatment.

Voxelotor modifies hemoglobin-oxygen affinity improving anemia and reducing hemolysis in sickle cell patients. However, the impact of Voxelotor on fetal hemoglobin (HbF) levels is unknown. We describe here variations of percentage of HbF measured by high performance liquid chromatography and mean corpuscular fetal Hb in a cohort of sickle cell patients treated with Voxelotor at Henri Mondor Sickle Cell Referral Center. Our data show a decrease in HbF levels in sickle cell patients after 6 months of treatment with Voxelotor, which is likely to be associated with an increase in the lifespan of red blood cells that are no longer prematurely removed from the circulation, particularly those with low HbF. This work raises the question of the risk of a rebound effect when stopping Voxelotor, which has a short half-life, during the time it takes to increase HbF.

A study of 28 pregnant women with sickle cell disease and COVID-19: elevated maternal and fetal morbidity rates.

Not available.

Plasma exchanges for the treatment of severe systemic necrotizing vasculitides in clinical daily practice: Data from the French Vasculitis Study Group.

The use of plasma exchanges (PLEX) in systemic necrotizing vasculitides (SNV) still need to be codified. To describe indications, efficacy and safety of PLEX for the treatment of SNV, we conducted a multicenter retrospective study on patients with ANCA-associated vasculitis (AAV) or non-viral polyarteritis nodosa (PAN) treated with PLEX. One hundred and fifty-two patients were included: GPA (n = 87), MPA (n = 56), EGPA (n = 4) and PAN (n = 5). PLEX were used for rapidly progressive glomerulonephritis (RPGN) in 126 cases (86%), alveolar hemorrhage in 64 cases (42%), and severe mononeuritis multiplex in 23 cases (15%). In patients with RPGN, there was a significant improvement in renal function compared to baseline value (P < 0.0001), the plateau being reached at month 3 after PLEX initiation, and estimated glomerular filtration rate improved especially as the number of PLEX increased. In patients with alveolar hemorrhage, mechanical ventilation was discontinued in all patients after a median time of 15 days. Patients treated for mononeuritis multiplex showed improvement of severe motor weakness. After a median follow of 22 months, 18 deaths (12%) were recorded, mainly in patients with RPGN and within the first 6 months. Incidence of end-stage renal disease and/or death was similar between groups of different baseline renal function, but was increased in MPO-ANCA compared to PR3-ANCA. Adverse events attributable to PLEX were recorded in 63%. No death occurred during PLEX. This large series describes indications, efficacy and safety of PLEX in daily practice. Randomized controlled studies are ongoing to define optimal indications, PLEX regimen and concomitant medications.

Central nervous system involvement of granulomatosis with polyangiitis: clinical-radiological presentation distinguishes different outcomes.

OBJECTIVE: The aim of this study was to describe the presentation and outcomes of patients with granulomatosis with polyangiitis (GPA) presenting with CNS involvement. METHODS: Patients were included in this nationwide retrospective study if they had GPA according to ACR criteria and/or the European Medicines Agency algorithm and CNS involvement. RESULTS: Thirty-five patients were included in the study. CNS involvement was observed in 51% of patients at GPA diagnosis. Headache (66%) was the main symptom, followed by sensory (43%) and motor impairment (31%). CNS involvement was characterized by pachymeningitis in 20, cerebral ischaemic lesions in 15 and haemorrhagic lesions in 2, with hypophyseal involvement in 2 patients. According to the clinical-radiological presentation, we distinguished granulomatous (G-CNS) and vasculitic (V-CNS) phenotypes. G-CNS patients more frequently had headaches, while V-CNS patients more frequently had motor impairment and renal involvement. Induction therapy produced clinical responses in 86% of patients. Baseline modified Rankin scale was higher for V-CNS than G-CNS patients (3 vs 2, P = 0.002). Initial spinal cord pachymeningitis was significantly associated with the need for a new induction regimen for relapsing/refractory disease (P = 0.01). Long-term neurological sequelae were noted in 51% of patients, including 35% with G-CNS and 69% with V-CNS (P = 0.08). Neurological sequelae were mainly noted in cases of spinal cord pachymeningitis (100%) and ischaemic or haemorrhagic lesions (73%). CONCLUSION: The clinical-radiological phenotype distinguished different long-term outcomes in patients with GPA and CNS involvement. Long-term neurological sequelae persisted in half of patients, mainly those with spinal cord pachymeningitis and vasculitic lesions.

Cardiac diastolic maladaptation is associated with the severity of exercise intolerance in sickle cell anemia patients.

This pilot study focusing on Sickle Cell Anemia (SCA) patients offers a comprehensive and integrative evaluation of respiratory, cardiovascular, hemodynamic, and metabolic variables during exercise. Knowing that diastolic dysfunction is frequent in this population, we hypothesize that a lack of cardiac adaptation through exercise might lead to premature increase in blood lactate concentrations in SCA patients, a potential trigger for acute disease complication. SCA patients were prospectively included in PHYSIO-EXDRE study and underwent a comprehensive stress test with a standardized incremental exercise protocol up to 4 mmol L-1 blood lactate concentration (BL4). Gas exchange, capillary lactate concentration and echocardiography were performed at baseline, during stress test (at ∼ 2 mmol L-1) and BL4. The population was divided into two groups and compared according to the median value of percentage of theoretical peak oxygen uptake (% V ˙ O 2 p e a k t h ) at BL4. Twenty-nine patients were included (42 ± 12 years old, 48% of women). Most patients reached BL4 at low-intensity exercise [median value of predicted power output (W) was 37%], which corresponds to daily life activities. The median value of % V ˙ O 2 p e a k t h at BL4 was 39%. Interestingly, diastolic maladaptation using echocardiography during stress test along with hemoglobin concentration were independently associated to early occurrence of BL4. As BL4 occurs for low-intensity exercises, SCA patients may be subject to acidosis-related complications even during their daily life activities. Beyond assessing physical capacities, our study underlines that diastolic maladaptation during exercise is associated with an early increase in blood lactate concentration.

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.

[Impact of voxelotor on hemoglobin electrophoretic and chromatographic profiles]. / Conséquences du traitement par voxelotor sur les profils électrophorétiques et chromatographiques de l'hémoglobine.

Voxelotor (GBT440, OXBRYTA®) appeared recently as one of the possible treatments for sickle cell disease. This molecule, by binding the alpha globin of hemoglobin, causes hyperaffinity of the latter for oxygen and reduces its polymerization properties. Several therapeutic trials have been able to show its effectiveness on certain aspects of sickle cell disease; thus, the french HAS (High Authority of Health) college issued an early access authorization and, since 2021, this treatment can be offered to patients under a temporary authorization for use. Consequently, the laboratories that carry out the biological monitoring of sickle cell patients will be confronted with new profiles characteristic of the presence of hemoglobin combined with GBT440. This work presents a collection of images obtained by different techniques: HPLC, capillary electrophoresis, isoelectrofocusing, alkaline gel and acid agar gel electrophoresis in transfused or non-transfused sickle cell disease patients. The ability to observe the presence of GBT440 by these analyzes could be useful in order to characterize the therapeutic follow-up of patients.

SARS-CoV-2 infection in patients with ß-thalassemia: The French experience.

INTRODUCTION: Because of iron overload complications, thrombosis and infectious predisposition, patients with severe forms of thalassemia are likely to be at increased risk of COVID-19 complications. RESULTS: A national survey conducted during the year 2020 across the French reference centers for hemoglobinopathies identified 16 cases of COVID-19 confirmed by RT-PCR in beta-thalassemia patients. Their age ranged from 11 months to 60 years. 15 patients were transfusion-dependent and 6 were splenectomized. Concerning iron overload related complications, none had diabetes or cirrhosis and only one had experienced heart failure. All 4 pediatric patients were pauci-symptomatic during the viral episode. Three patients (41, 49 and 57 years old) developed COVID-19 pneumonia requiring oxygen therapy without the need for mechanical ventilation. Neutropenia (absolute neutrophils count <0.5 10 9/L) was observed in 2 patients receiving long-term treatment with hydroxycarbamide and deferiprone. No thrombosis event, organ failure or death occurred. All patients recovered. CONCLUSION: Severity of COVID-19 in this population of young and middle-aged patients appeared increased compared to the general population but remained mild to moderate as already described in the few series reported in the literature. Occurrence of adverse events related to chronic treatment administered in thalassemia disease may be favored by the infectious episode.

Thromboprophylaxis Reduced Venous Thromboembolism in Sickle Cell Patients with Central Venous Access Devices: A Retrospective Cohort Study.

Sickle cell disease (SCD) induces a chronic prothrombotic state. Central venous access devices (CVADs) are commonly used for chronic transfusions and iron chelation in this population. CVADs are an additional venous thromboembolism (VTE) risk factor. The role of thromboprophylaxis in this setting is uncertain. The objectives are: (1) to determine whether thromboprophylaxis reduces VTE risk in SCD patients with CVAD and (2) to explore characteristics associated with VTE risk. We identified adults with SCD and CVAD intended for chronic use (≥3 months) at two comprehensive SCD centers. Thromboprophylaxis presence; type; intensity; and patient-, catheter-, and treatment-related VTE risk factors were recorded. Among 949 patients, 49 had a CVAD (25 without and 24 with VTE prophylaxis). Thromboprophylaxis type and intensity varied widely. Patients without thromboprophylaxis had higher VTE rates (rate ratio (RR) = 4.0 (95% confidence interval: 1.2−12.6), p = 0.02). Hydroxyurea was associated with lower VTE rates (RR = 20.5 (6.4−65.3), p < 0.001). PICC lines and Vortex and Xcela Power implantable devices were associated with higher rates compared with Port-a-Cath (RR = 5.8 (1.3−25.9), p = 0.02, and RR = 58.2 (15.0−225.0), p < 0.001, respectively). Thromboprophylaxis, hydroxyurea, and CVAD subtype were independently associated with VTE. The potentially protective role of thromboprophylaxis and hydroxyurea for VTE prevention in patients with SCD and CVAD merits further exploration.

Prevalence and Significance of Non-conventional Antiphospholipid Antibodies in Patients With Clinical APS Criteria.

Background: The biological diagnostics of antiphospholipid syndrome (APS) takes into account the persistent positivity for anticardiolipin and/or anti-ß2GP1 antibodies and/or presence of lupus anticoagulant (LA). However, some non-conventional antiphospholipid antibodies have emerged that could help in the diagnosis of APS. Objectives: To study the potential usefulness of non-conventional antiphospholipid antibodies in clinical practice. Methods: Eighty-seven patients, aged from 15 to 92 years were included and classified in following groups: 41 patients positive for the conventional antibodies with clinical criterion of APS (31 with primary APS and 10 secondary), 17 seronegative APS (SNAPS) patients (i.e., persistent negativity for the conventional antibodies with a strong clinical suspicion of APS), 11 asymptomatic antiphospholipid antibodies carriers (i.e., persistent positivity for the conventional antibodies without clinical evidence of APS), and 18 patients presenting with a first thrombotic or obstetrical event. IgG and IgM were detected to the following antigens: phosphatidylserine/prothrombin (PS/PT) by ELISA, and phosphatidic acid, phosphatidyl-ethanolamine, phosphatidyl-glycerol, phosphatidyl-inositol, phosphatidylserine, annexin V, prothrombin by immunodot. Anti-ß2GP1 IgA, and anti-ß2GP1 domain 1 IgG were detected by chemiluminescence. Results: Positivity for the non-conventional antibodies was correlated with APS severity; patients with catastrophic APS (CAPS) being positive for 10.7 (Median, Range: 5-14) non-conventional antibodies. 9/17 seronegative patients were positive for at least one of non-conventional antibodies. A study of non-supervised hierarchical clustering of all markers revealed that anti-PS/PT antibodies showed high correlation with the presence of LA. All patients with APS triple positivity (highest risk profile) exhibited also persistent positivity for anti-PS/PT antibodies. Conclusions: Our data obtained from a prospective cohort constituted mainly by patients with primary APS, suggest that non-conventional APS antibodies may be useful for patients classified as SNAPS. They demonstrate the potential value of aPS/PT antibodies as a strong marker of APS. We propose that anti-PS/PT antibodies could be a surrogate APS biological marker of LA to classify in high-risk profile patients treated by direct oral anticoagulants (DOACs), in whom LA detection cannot be achieved.

High bone mineral density in sickle cell disease: Prevalence and characteristics.

BACKGROUND: Osteosclerosis (OSC) is a rarely studied complication of sickle cell disease (SCD). The objective of our study was to determine the prevalence and characteristics of high bone mineral density (BMD) and its radiological features in adult SCD patients. METHODS: This prospective observational study was conducted from May 2007 to May 2016 in consecutive patients with steady-state SCD at two university hospitals. The BMD of the lumbar spine (L1-L4) and right femoral neck was determined by dual energy X-ray absorptiometry. Clinical, laboratory and radiographic data were recorded. High BMD was defined as a BMD Z-score of at least +2.5 standard deviations at the lumbar spine or hip. The characteristics of the patients with high BMD were compared to those of individuals with low or middle BMD, using multivariate ordinal logistic regression. RESULTS: 135 patients (86 women and 49 men) with a median age of 27 (IQR 23-33) years were included. High BMD was diagnosed in 20 (15%) patients with a median age of 33.5 (IQR 28-45) years. The SCD genotypes of these patients were SS in 11, SC in 5, S/beta+ in 3, and S/beta0 in 1. High BMD patients more frequently harbored the S/beta SCD genotype (21% vs 5% in non-high BMD patients; p=0.047) and were older (p=0.0007). Compared to patients with low or middle BMD, after adjustment for age and SCD genotype, high BMD patients had a higher prevalence of avascular necrosis history (p=0.009), higher BMI (p=0.007), and lower serum resorption marker CTX (p=0.04), bilirubin (p=0.02) and parathyroid hormone levels (p=0.02). There were no differences between groups regarding fracture history, H-shaped vertebrae or other biological variables. CONCLUSION: High-BMD values is a common manifestation in SCD patients, especially in those with the S/beta-thalassemia genotypes. The prevalence of high-BMD in SCD is associated with older age, suggesting that it will be more common in the future because the life span of patients with SCD is increasing thanks to significant progress in SCD treatment.

Extreme hypomagnesemia: characteristics of 119 consecutive inpatients.

Extreme hypomagnesemia (hypoMg) can be encountered in many situations, but little data currently exist. Our aim is to describe the epidemiological, clinical, etiological characteristics, and the biological abnormalities of consecutive inpatients with extreme hypomagnesemia. In our observational monocentric study, between 1st July 2000 and April 2015, all inpatients with extreme hypomagnesemia, defined by at least one plasma magnesium concentration (PMg) below 0.3 mmol/L, were included. Demographic, clinical, biological characteristics and the drugs prescribed before the qualifying PMg measurement were retrospectively collected. 41,069 patients had at least one PMg assessment. The prevalence of extreme hypomagnesemia is 0.3% (119 inpatients). The median age is 70 years, 52% are women. The patients were mainly hospitalized in intensive care (n = 37, 31.1%), oncology (n = 21, 17.6%), gastroenterology (n = 18, 15.1%) and internal medicine (n = 16, 13.4%) departments. One hundred patients (84%) had a medical history of gastrointestinal disease (39% with bowel resections, 24% with stoma), and 50 (42%) had a cancer history. The drugs most commonly prescribed (known to induce hypoMg) are proton pump inhibitors (PPI) (n = 77, 70%), immunosuppressive regimens (n = 25, 22.5%), platinum salt-based chemotherapies (n = 19, 17.1%), and diuretics (n = 22, 19.8%). The suspected causes of hypomagnesemia are often multiple, but drugs (46%, including PPI in 19%) and chronic gastrointestinal disorders (37%) are prominent. Associated electrolyte disturbances include hypocalcemia (77%) and mild hypokalemia (51%). The 1-month mortality from all causes is 16%. Extreme hypomagnesemia is rare in inpatients, and is frequently associated with severe hypocalcemia. Digestive disorders and drugs are the main contributory causes.