Fadi Haddad

Atrial fibrillation (AF) is the most prevalent sustained arrhythmia and is increasingly driven by cardiometabolic disease, including type 2 diabetes mellitus (T2DM), obesity, and insulin resistance. These conditions promote atrial electrical instability and a permissive substrate through mitochondrial dysfunction, oxidative stress, inflammation, calcium-handling abnormalities, and profibrotic signaling, culminating in atrial fibrosis and conduction heterogeneity. Metformin, the foundational glucose-lowering therapy for T2DM, exerts pleiotropic actions that intersect with these upstream pathways. Beyond glycemic control, metformin induces mild mitochondrial complex I modulation with reduction of reverse electron transfer-derived reactive oxygen species, activates adenosine monophosphate (AMP) activated protein kinase, and attenuates nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB)-mediated cytokine signaling; experimental data further suggest favorable effects on adiponectin–sarcoendoplasmic reticulum calcium adenosine triphosphatase (SERCA) 2a-dependent calcium cycling, connexin expression, small-conductance Ca²⁺-activated K+ channel remodeling, lipid handling, and transforming growth factor-β (TGF)-β-associated fibrotic remodeling. Observational cohort studies have reported associations between metformin exposure and a modest reduction in incident AF, particularly with longer treatment duration and in higher-risk metabolic phenotypes; device-based surveillance cohorts support a preventive association for new-onset AF rather than reduction of established AF burden. Data after catheter ablation suggest improved freedom from recurrence in metformin-treated patients, whereas evidence in postoperative AF is largely neutral, likely reflecting distinct acute mechanisms. Collectively, metformin may be best conceptualized as a potential substrate-modifying, upstream therapy candidate; however, confounding, exposure misclassification, and heterogeneity in comparators limit causal inference, underscoring the need for prospective randomized trials with AF endpoints. In practice, integration with comprehensive risk-factor modification (blood pressure, weight, sleep apnea, and glycemic optimization) remains essential when considering AF prevention strategies.

Rationale: Parosteal lipomas are rare neoplasms comprising mature adipocytes situated in a proximity to bone. Although these tumors follow a benign course, the reactive osseous changes that may occur with such lesions might raise the suspicion of malignancy. Patient Concerns: Here we present a case of a 33-year-old male patient complaining of pain and swelling in the right anterior forearm without history of trauma. Diagnosis: An magnetic resonance imaging of the region revealed a lobulated intramuscular fat intensity mass within the supinator muscle. Bony projection inseparable from the anterolateral radial diaphyseal cortex and periosteum was also seen. The radiological features suggested the diagnosis of parosteal lipoma. Intervention: After the radiological diagnosis of a parosteal lipoma, the patient was offered a total surgical excision of the mass. Outcomes: The mass was removed successfully. Histopathology showed mature benign adipose tissue bordered by thin fibrous septa confirming the diagnosis of parosteal lipoma. Follow-up magnetic resonance imaging after 6 months did not reveal any signs of complications or recurrence. Lessons: Distinction of the features of parosteal lipomas is needed to establish the accurate diagnosis, discriminate it from malignant lesions, predict potential neurovascular compromises, and follow up until a curative action is planned.

The occurrence of intestinal stenosis is a common and potentially serious complication of Crohn’s disease (CD). These strictures represent 20% of the surgical indications in CD. Endoscopic dilation is an alternative to surgery for endoscopically accessible stenosis. The aim of this study is to evaluate the effectiveness of endoscopic balloon dilation (EBD) in CD intestinal stenosis. This retrospective, descriptive study realized between January 2015 and October 2020, included CD patients diagnosed at least 6 months before and complicated with symptomatic intestinal stenosis (abdominal pain, bloating, nausea and vomiting). Anorectal strictures were excluded. All patients had a cross-sectional imaging before intestinal dilation to determine the characteristics of the stenosis and exclude abscess and fistula tract near the stenosis which constitute a contraindication of EBD. All patients underwent an EBD during a colonoscopy under sedation by propofol. The short-term success of EBD has been established on both technical (passage of the endoscope across the site of stenosis after dilation) and clinical level (relief of intestinal obstructive symptoms). The long-term efficacy was defined by no need for surgery within 6 months after dilation. Twelve patients (6 males and 6 females), with an average age of 32 years +/-7.7, were included. The average interval between onset of CD and the onset of intestinal stricture was 8 years. Eight patients had a history of bowel resection. The stenosis was located at the terminal ileum or ileocaecal valve in 4 cases, ileocolic anastomosis in 8 cases. The stenosis was ulcerated in 9 cases, inflammatory in 5 cases and polypoid in 3 cases. All patients were on medical treatment corticosteroids, Azathioprine and / or Anti TNF. We performed 18 EBD, divided into several sessions depending on the degree of stenosis (1 EBD, 2 EBD and 3 EBD in respectively 11, 3 and 2 patients). Two patients required surgery for persisting symptoms. Technical success was obtained in 11 patients (92% of cases). Clinical success, defined by a disappearance of clinical symptoms with an HBI score of less than 4, was obtained in 9 patients (75% of cases). The mean follow-up after dilation was 23 months (range from 8 to 42 months). No major complications were observed in this study. EBD is an effective therapeutic technique relatively safe for intestinal CD stenosis, allowing to delay or better, to avoid surgical treatment when the stenosis is well selected (stenosis<4cm, single, anastomotic, non-angled, and without adjacent abscess or fistula).