Background: Obstructive sleep apnea is associated with increased risk of sudden cardiac death.
Objective: The purpose of this study was to elucidate changes in ventricular repolarization and electromechanical interaction during obstructive respiratory events simulated by intermittent negative upper airway pressure (INAP) in pigs. We also investigated the effect of a reduced repolarization reserve in drug-induced long QT (LQT) following INAP-induced changes in ventricular repolarization.
Methods: In sedated spontaneously breathing pigs, 75 seconds of INAP was applied by a negative pressure device connected to the endotracheal tube. Ventricular electromechanical coupling was determined by the electromechanical window (EMW) before (pre-INAP), during (INAP), and after INAP (post-INAP). Incidence rates of premature ventricular contractions (PVCs) were measured respectively. A drug-induced LQT was modeled by treating the pigs with the hERG1 blocker dofetilide (DOF).
Results: Whereas QT interval increased during and decreased after INAP (pre-INAP: 273 ± 5 ms; INAP 281 ± 6 ms; post-INAP 254 ± 9 ms), EMW shortened progressively throughout INAP and post-INAP periods (pre-INAP 81 ± 4 ms; post-INAP 44 ± 7 ms). DOF shortened EMW at baseline. Throughout INAP, EMW decreased in a comparable fashion as before DOF (pre-INAP/+DOF 61 ± 7 ms; post-INAP/+DOF 14 ± 9 ms) but resulted in shorter absolute EMW levels. Short EMW levels were associated with increased occurrence of PVCs (pre-INAP 7 ± 2 ms vs post-INAP 26 ± 6 ms; P = .02), which were potentiated in DOF pigs (pre-INAP/+DOF 5 ± 2 ms vs post-INAP/+DOF 40 ± 8 ms; P = .006). Administration of atenolol prevented post-INAP EMW shortening and decreased occurrence of PVCs.
Conclusion: Transient dissociation of ventricular electromechanical coupling during simulated obstructive respiratory events creates a dynamic ventricular arrhythmogenic substrate, which is sympathetically mediated and aggravated by drug-induced LQT.
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http://dx.doi.org/10.1016/j.hrthm.2021.03.017 | DOI Listing |
J Infect Dev Ctries
December 2024
Department of Radiology, University of Health Sciences, Bursa Faculty of Medicine, City Training and Research Hospital, Bursa, Turkey.
Introduction: We aimed to present the changes that may occur in pulmonary functions in children who experienced more severe coronavirus disease 2019 (COVID-19) during long-term follow-up.
Methodology: A prospective longitudinal observational cohort study was conducted with 34 pediatric patients (7-18 years) who were hospitalized with COVID-19 infection (moderate n = 25, severe n = 9), and followed up at our Pediatric Infection Outpatient Clinic for approximately two years. Pulmonary function tests (PFTs) were performed using spirometry.
BMC Endocr Disord
January 2025
Department of Respiratory and Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, 430060, China.
Background: Menopause is a significant phase in women's health, in which the incidence of obstructive sleep apnea (OSA) is significantly increased. Body fat distribution changes with age and hormone levels in postmenopausal women, but the extent to which changes in body fat distribution affect the occurrence of OSA is unclear.
Methods: This research performed a cross-sectional analysis utilizing data from the 2015-2016 National Health and Nutrition Examination Survey (NHANES).
BMC Infect Dis
January 2025
Department of Respiratory Medicine, Faculty of Medicine, Hokkaido University, North 15 West 7, Kita-ku, Sapporo, 060-8638, Japan.
Background: Mycobacterium avium complex (MAC) is a common pathogen causing non-tuberculous mycobacterial infections, primarily affecting the lungs. Disseminated MAC disease occurs mainly in immunocompromised individuals, such as those with acquired immunodeficiency syndrome, hematological malignancies, or those positive for anti-interferon-γ antibodies. However, its occurrence in solid organ transplant recipients is uncommon.
View Article and Find Full Text PDFSci Rep
January 2025
School of Computing, SASTRA Deemed University, Thanjavur, Tamil Nadu, India.
Mechanical ventilation is the process through which breathing support is provided to patients who face inconvenience during respiration. During the pandemic, many people were suffering from lung disorders, which elevated the demand for mechanical ventilators. The handling of mechanical ventilators is to be done under the assistance of trained professionals and demands the selection of ideal parameters.
View Article and Find Full Text PDFAnn Vasc Surg
January 2025
Division of Vascular Surgery and Endovascular Therapy, Keck Medical Center of University of Southern California. 1520 San Pablo Street HCT 4300, Los Angeles, California, 90033. Electronic address:
Objectives: This study assessed the association between chronic obstructive pulmonary disease (COPD) severity and postoperative mortality among patients undergoing thoracic endovascular aortic repair (TEVAR) and complex endovascular aortic repair (CEVAR).
Methods: A retrospective review of the Vascular Quality Initiative database identified elective TEVAR and CEVAR cases from 2013-2022 with endograft proximal landing zone ≥2 for thoracic or complex abdominal aortic disease. Symptomatic disease, ruptures, and urgent/emergent surgeries were excluded.
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