Background: Prior experimental studies show that thoracic spinal cord stimulation (SCS) improves left ventricular (LV) ejection fraction (LVEF). The mechanism of this improvement in the LV contractile function after SCS and its effects on the myocardial oxygen consumption remains unknown.
Methods And Results: We performed thoracic SCS (T1-T2 level) followed by 4 weeks of rapid ventricular pacing in 9 adult pigs with ischemic heart failure (HF) induced by myocardial infarction (MI). At 24 hours off-pacing, detailed echocardiogram and invasive hemodynamic assessment were performed to determine LV contractile function and myocardial oxygen consumption. Serum norepinephrine level was measured before and after SCS. SCS was performed on 2 occasions for 15 minutes, 30 minutes apart (recovery) with 50 Hz frequency (pulse width 0.2 millisecond, 90% of motor threshold at 2 Hz output). Echocardiogram revealed significant decrease in LVEF (33.8 ± 1.8% vs 66.5 ± 1.7%, P < 0.01) after induction of MI and HF. Compared with MI and HF, acute SCS significantly increased LVEF and +dP/dt (all P < 0.05). Withdrawal of SCS during recovery decreased +dP/dt, but not LVEF that increased again with repeated SCS. Myocardial oxygen consumption also significantly decreased during SCS compared with MI and HF (P = 0.006) without any change in serum norepinephrine level (P = 0.9). Speckle tracking imaging showed significant improvement in global and regional circumferential strains over the infarcted mid and apical regions, decreased in time to peak circumferential strain over the lateral and posterior wall after SCS, and the degree of intraventricular dyssynchrony during SCS compared with MI and HF (P < 0.05).
Conclusions: In a porcine model of ischemic HF, acute SCS improved global and regional LV contractile function and intraventricular dyssynchrony, and decreased myocardial oxygen consumption without elevation of norepinephrine level.
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http://dx.doi.org/10.1111/j.1540-8167.2011.02230.x | DOI Listing |
J Am Chem Soc
January 2025
State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences; Research Unit of Nanocatalytic Medicine in Specific Therapy for Serious Disease, Chinese Academy of Medical Sciences (2021RU012), Shanghai 200050, P. R. China.
Diabetic cardiomyopathy (DCM) is one of the most lethal complications of diabetes and is induced by the overproduction of reactive oxygen species (ROS) in cardiomyocytes due to sustained high glucose levels, leading to cardiac oxidative damage and final sudden death. Drugs and antioxidants currently applied to the clinical therapy of DCM fail to scavenge ROS efficiently, resulting in compromised therapeutic efficacy. Herein, a nanocatalytic antioxidative therapeutic strategy is proposed for DCM treatment.
View Article and Find Full Text PDFBioact Mater
April 2025
School of Medicine South China University of Technology, Guangzhou, Guangdong, 510006, China.
The cardiac microenvironment profoundly restricts the efficacy of myocardial regeneration tactics for the treatment of myocardial infarction (MI). A prospective approach for MI therapeutics encompasses the combined strategy of scavenging reactive oxygen species (ROS) to alleviate oxidative stress injury and facilitating macrophage polarization towards the regenerative M2 phenotype. In this investigation, we fabricated a ROS-sensitive hydrogel engineered to deliver our previously engineered IL-1β-VHH for myocardial restoration.
View Article and Find Full Text PDFCureus
December 2024
Diabetes and Endocrinology, United Lincolnshire Hospital NHS Trust, Lincoln, GBR.
The cardiovascular implications of thyroid disease have been recognized as one of the most characteristic signs that result from the effect of thyroid hormone (TH). Both hyperthyroidism and hypothyroidism produce changes in cardiac contractility, myocardial oxygen consumption, cardiac output, blood pressure, and systemic vascular resistance. The bradyarrhythmias, including atrioventricular block and sick sinus syndrome, are exceedingly rare in hyperthyroidism.
View Article and Find Full Text PDFAppl Biochem Biotechnol
January 2025
Department of Internal Medicine-Cardiovascular, Guangzhou Twelfth People's Hospital, No.1, Tianqiang Road, Tianhe District, Guangzhou City, Guangdong Province, 510620, China.
Myocardial infarction (MI) is a coronary artery-related disease that seriously threatens human life and is the leading cause of sudden death worldwide, where a lack of nutrients and oxygen leads to an inflammatory response and death of cardiomyocytes. Ferroptosis is a form of non-apoptotic cell death associated with metabolic dysfunction, resulting in abnormal breakdown of glutamine and iron-dependent accumulation of reactive oxygen species (ROS) during metabolism. However, the molecular mechanism of ferroptosis in the pathogenesis of MI and the function of Klotho and KRAS on ferroptosis during MI remain unclear.
View Article and Find Full Text PDFMultimed Man Cardiothorac Surg
January 2025
Congenital Heart Center, Division of Cardiovascular Surgery, Department of Surgery, University of Florida, Gainesville, FL, USA.
Venoarterial extracorporeal membrane oxygenation weaning strategies are not standardized. When dealing with patients with complex physiologies and borderline haemodynamics, it is prudent to have a fail-safe method of approaching decannulation from extracorporeal membrane oxygenation. Standardizing the extracorporeal membrane oxygenation weaning strategy with a pump-controlled retrograde trial off protocol seems a feasible alternative to traditional venoarterial extracorporeal membrane oxygenation weaning approaches.
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