Research Article
Genetic Variability of Pitx2 Exon 4 in Senegalese Patients with Rheumatic Mitral Valve Disease with and Without Atrial Fibrillation: A Prospective Study with in Silico Analysis
Issue:
Volume 1, Issue 2, June 2026
Pages:
53-61
Received:
10 February 2026
Accepted:
16 March 2026
Published:
28 March 2026
Abstract: Introduction: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and is associated with significant morbidity and mortality. In sub-Saharan Africa, AF frequently occurs at a younger age, most often in the context of rheumatic mitral valve disease (RMVD), and is characterized by advanced atrial remodeling. Genetic studies have identified the Paired-like Homeodomain Transcription Factor 2 (PITX2) gene at the 4q25 locus as a major susceptibility factor for AF. Objective: to investigate genetic variability within exon 4 of the PITX2 gene in African patients with RMVD and to explore its potential role in AF susceptibility. Materials and Methods: this prospective observational study was conducted at the Cuomo Cardiac Surgery Center, Aristide Le Dantec University Hospital (Dakar, Senegal). Forty-five patients undergoing surgery for RMVD were included, along with 15 control subjects without documented AF. Intraoperative left atrial endocardial biopsies were obtained in operated patients. Genomic Deoxyribonucleic Acid (DNA) extracted from atrial tissue and control blood samples was used for targeted amplification and Sanger sequencing of exon 4 of PITX2. Identified variants were annotated using public databases and evaluated with in silico prediction tools. Variants were classified according to the American College of Medical Genetics and Genomics (ACMG) guidelines. Results: the study population was young (mean age 31 years) and predominantly female. AF was present in 56% of patients and was associated with marked left atrial dilatation and preserved left ventricular systolic function. Sequencing identified four rare missense variants (c.59C>T, c.97A>G, c.121C>G, and c.149G>T) located within the conserved homeobox domain of PITX2. All variants were heterozygous and showed extremely low allele frequencies in population databases. In silico predictions were heterogeneous, and all variants were classified as variants of uncertain significance. Genetic diversity analyses revealed slightly higher haplotype and nucleotide diversity in AF patients, without significant genetic differentiation between groups. Conclusion: rare variants in exon 4 of PITX2 were identified in African patients with RMVD. Although their functional significance remains uncertain, these findings support a potential modulatory role of PITX2 in susceptibility to atrial fibrillation and highlight the importance of genetic studies in underrepresented African populations.
Abstract: Introduction: Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia and is associated with significant morbidity and mortality. In sub-Saharan Africa, AF frequently occurs at a younger age, most often in the context of rheumatic mitral valve disease (RMVD), and is characterized by advanced atrial remodeling. Genetic studies have ...
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Research Article
Effectiveness and Safety of Clonidine for Controlling Blood Loss, Hemodynamic Stability, and Surgical Field Quality in Oral and Maxillofacial Surgery: A Systematic Review and Meta-analysis of Randomized Controlled Trials
Issue:
Volume 1, Issue 2, June 2026
Pages:
62-78
Received:
6 March 2026
Accepted:
25 March 2026
Published:
7 April 2026
DOI:
10.11648/j.sdmed.20260102.12
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Abstract: Background: Clonidine is an α-adrenoreceptor agonist that reduces sympathetic outflow and releases certain neurotransmitters by acting on receptors in the brain and peripheral tissues. The aim of this systematic review and meta-analysis is about the effectiveness and safety of clonidine for controlling blood loss, hemodynamic stability and surgical field quality comparing with tranxemic acid, placebo and dexmedetomidine. The randomized controlled trials that determine the effect of clonidine on blood loss, hemodynamic stability, and surgical field quality in adult patients undergoing oral and maxillofacial surgery were included. The articles included in this systematic review were searched through the electronic databases PubMed, Cochrane Library, and Google Scholar from July to September 17, 2025. The primary outcomes were controlling blood loss, hemodynamic stability, and surgical field quality. Secondary outcomes were duration of surgery and adverse events. The risk of bias was assessed by the Cochrane Collaboration tool (ROB2). Subgroup and sensitivity analysis was conducted to investigate the study of high risk of bias. Mean difference and relative risk with a 95% confidence interval were used for analysis. There were 15 articles included in the review after screening 615, with a total population of 1143. Clonidine was less blood loss than tranxemic acid (MD=40.17, 95% CI: 4.95- 75.38; p=0.03), more blood loss control than with placebo (MD=-75.15, 95% CI: -96.04-54.25; p <0.00001), and less blood loss control than with dexmedetomidine (MD=7.65, 95% CI: 1.19-14.11; p=0.02). Clonidine maintained mean arterial blood pressure than placebo (MD = -3.87, 95% CI: -6.01--1.72; p = 0.0004). Clonidine is maintained MAP in normal range than placebo when administered Pre-induction (MD=-1.88,95% CI: -3.7--0.07; p=0.04) compared with post induction (MD = -8.16.95% CI: -13.7--2.62; p=0.004). Clonidine has less poor and fair surgical field quality than placebo (RR=0.1, 95% CI: 0.02-0.42, p=0.002; RR=0.82, 95% CI: 0.67-1, p=0.05) respectively. Clonidine decreases blood loss more than placebo. Clonidine is less likely inferior to dexmedetomidine to reducing blood loss for oral and maxillofacial surgery. Clonidine maintains mean arterial blood pressure in the normal range than placebo when administered pre-induction than after induction. Clonidine maintains MAP before induction, and it is effective pre-induction as well as post-induction to maintain a mean heart rate comparable with dexmedetomidine. Clonidine is shortening the duration of surgery comparably with tranxemic acid and dexmedetomidine but more than placebo.
Abstract: Background: Clonidine is an α-adrenoreceptor agonist that reduces sympathetic outflow and releases certain neurotransmitters by acting on receptors in the brain and peripheral tissues. The aim of this systematic review and meta-analysis is about the effectiveness and safety of clonidine for controlling blood loss, hemodynamic stability and surgical...
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Mbaye Fatimata
