Ventricular Septal Defect and Mitral Regurgitation Due to Penetrating Cardiac Trauma; a Case Report and Review of Literature

Penetrating cardiac trauma is a fatal condition and can result in the injury of various parts of the heart. Ventricular Septal Defect (VSD) following these traumas occurs only in 1-5% of cases. The patients' conditions depend on location, size, and concomitant injuries. One of the uncommon coincidences with the VSD is Mitral Regurgitation (MR) due to injury to sub-valvular structures. In this study, we report a case of concomitant traumatic-induced VSD and MR in a 14-year-old boy following a stab wound to his chest. The patient was a teenage boy coming to the Rajaei Cardiology Hospital emergency room following a stab wound to the anterior and left part of his chest. Despite primary urgent surgery, his breathlessness had continued for three more months. Evaluations with Transthoracic Echocardiography (TTE) revealed VSD with concomitant MR, but there was no papillary muscle rupture. Cardiac Magnetic Resonance Imaging (MRI) and angiographic evaluation confirmed the provisional diagnosis. The Amplatzer VSD occluder repaired the VSD, and the patient was discharged following the resolution of his symptoms. Although the MR has been present in the follow-up echocardiography, the patient has been asymptomatic. Since the initial presenting symptoms and signs of VSD and MR might be subtle or delayed, imaging modalities such as TTE and Transesophageal Echocardiogram (TEE) are beneficial in determining the diagnosis and the optimal treatment.

Targeted delivery of extracellular vesicles in heart injury

Extracellular vesicles (EVs) are nanoscale extracellular vesicles derived from endocytosis that are crucial to intercellular communication. EVs possess natural biocompatibility and stability that allow them to cross biological membranes and that protect them from degradation. Recent studies have shown that EVs-mediated crosstalk between different cell types in the heart could play important roles in the maintenance of cardiac homeostasis and the pathogenesis of heart diseases. In particular, EVs secreted by different types of stem cells exhibit cardioprotective effects. However, numerous studies have shown that intravenously injected EVs are quickly cleared by macrophages of the mononuclear phagocyte system (MPS) and preferentially accumulate in MPS organs such as the liver, spleen, and lung. In this review, we discuss exosome biogenesis, the role of EVs in heart diseases, and challenges in delivering EVs to the heart. Furthermore, we extensively discuss the targeted delivery of EVs for treating ischemic heart disease. These understandings will aid in the development of effective treatment strategies for heart diseases.

A Dedicated Stitch to Allow Early Safe Mobilization Avoiding Drain-Induced Heart Injury

Placement of a mediastinal drain is a routine procedure following heart surgery. Postoperative bed rest is often imposed due to the fear of potential risk of drain displacement and cardiac injury. We developed an encapsulating stitch as a feasible, effective and low-cost technique, which does not require advanced surgical skills for placement. This simple, novel approach compartmentalizes the drain allowing for safe early mobilization following cardiac surgery.

Metformin Protects Against Radiation-Induced Heart Injury and Attenuates the Upregulation of Dual Oxidase Genes Following Rat's Chest Irradiation

Radiation-induced heart toxicity is one of the serious side effects after a radiation disaster or radiotherapy for patients with chest cancers, leading to a reduction in the quality of life of the patients. Evidence has shown that infiltration of inflammatory cells plays a key role in the development of functional damages to the heart via chronic upregulation of some pro-fibrotic and pro-inflammatory cytokines. These changes are associated with continuous free radical production and increased stiffness of heart muscle. IL-4 and IL-13 are two important pro-fibrotic cytokines which contribute to the side effects of ionizing radiation exposure. Recent studies have proposed that IL-4 through upregulation of DUOX2, and IL-13 via stimulation of DUOX1 gene expression, are involved in the development of radiation late effects. In the present study, we aimed to detect changes in the expression of these pathways following irradiation of rat’s heart. Furthermore, we evaluated the possible protective effect of metformin on the development of these abnormal changes. 20 male rats were divided into 4 groups (control, radiation, metformin treated, metformin + radiation). These rats were irradiated with 15 Gy ⁶⁰Co gamma rays, and sacrificed after 10 weeks for evaluation of the changes in the expression of IL4R1, IL-13R2a, DUOX1 and DUOX2. In addition, the levels of IL-4 and IL-13 cytokines, as well as infiltration of macrophages and lymphocytes were detected. Results showed an upregulation of both DUOX1 and DUOX2 pathways in the presence of metformin, while the level of IL-13 did not show any significant change. This was associated with infiltration of macrophages and lymphocytes. Also, treatment with metformin could significantly attenuate accumulation of inflammatory cells, and upregulate these pathways. Therefore, suppression of dual oxidase genes by metformin may be a contributory factor to its protective effect.