Ischemic heart disease refers to myocardial degeneration, necrosis, and fibrosis caused by coronary artery disease. It can lead to severe left ventricular dysfunction (LVEF ≤ 35–40%) and is a major cause of heart failure (HF). In each contraction, myocardium is subjected to a variety of mechanical forces, such as stretch, afterload, and shear stress, and these mechanical stresses are clinically associated with myocardial remodeling and, eventually, cardiac outcomes. Mitochondria produce 90% of ATP in the heart and participate in metabolic pathways that regulate the balance of glucose and fatty acid oxidative phosphorylation. However, altered energetics and metabolic reprogramming are proved to aggravate HF development and progression by disturbing substrate utilization. This review briefly summarizes the current insights into the adaptations of cardiomyocytes to mechanical stimuli and underlying mechanisms in ischemic heart disease, with focusing on mitochondrial metabolism. We also discuss how mechanical circulatory support (MCS) alters myocardial energy metabolism and affects the detrimental metabolic adaptations of the dysfunctional myocardium.

The incidence of atrial fibrillation (AF) increases with age, and telomere length gradually shortens with age. However, whether telomere length is related to AF is still inconclusive, and the exact mechanism by which aging causes the increased incidence of AF is still unclear. We hypothesize that telomere length is correlated with aging-related AF and that mitochondrial dysfunction plays a role in this. This research recruited 96 elderly male patients with AF who were admitted to the Second Medical Center of Chinese PLA General Hospital from April to October 2018. After matching by age and gender, 96 non-AF elderly male patients who were admitted to the hospital for physical examination during the same period were selected as controls. Anthropometric, clinical, and laboratory analyses were performed on all subjects. The mitochondrial membrane potential (MMP) of peripheral blood leukocytes was detected as the indicator of mitochondrial function. Compared with the control group, the leukocyte telomere length (LTL) was significantly shorter ( P < 0.001 ), and the level of PGC-1α in serum was significantly lower in AF patients. Additionally, in subjects without any other diseases, the AF patients had lower MMP when compared with the control. Multivariate logistic regression confirmed that LTL (OR 0.365; 95% CI 0.235-0.568; P < 0.001 ) and serum PGC-1α (OR 0.993; 95% CI 0.988-0.997; P = 0.002 ) were inversely associated with the presence of AF. In addition, ROC analysis indicated the potential diagnostic value of LTL and serum PGC-1α with AUC values of 0.734 and 0.633, respectively. This research concludes that LTL and serum PGC-1α are inversely correlated with the occurrence of aging-related AF and that mitochondrial dysfunction plays a role in this.

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This study was designed to analyse the characteristics and aetiology of lowtemperature burns and explore the prevention and treatment strategies. In total, 206 patients hospitalised with low-temperature burns in a major burn center in Beijing from 2017 to 2021 were included. There were 35-49 cases per year, with an average of 41 ± 4.5 cases. The prevalence of low-temperature burns was higher in female than in male and are mainly resulted from two kinds of incidents: unintended burns from heat treatment (50.97%, 105/206) and improper use of heating devices to keep warm (43.69%, 90/206). Most cases occurred in autumn (33.01%, 68/206) and the least in spring (17.96%, 37/206); cases in summer (24.27%, 50/206) and winter (24.76%, 51/206) accounted for nearly a quadrant respectively. Low-temperature burns in summer were mainly unintended burns from heat treatment (80%, 40/50), whereas in autumn were mainly resulted from improper use of heating devices to keep warm (55.88%, 38/68), the difference was statistically significant (χ 2 = 42.801, P < .001). Of all the cases, the burn size ranged from 0.2% to 5% TBSA, mostly less than 1% (85.92%, 177/206); third-degree burns accounted for 98.54% (203/206). Patients admitted after 3 weeks post-injury accounted for 42.23% (87/206). All patients were cured, and most of them were by surgeries (70.87%, 146/206). The results of the study show that low-temperature burn injury features a predictable morbidity among different seasons, a higher prevalence in adult women and a frequent occurrence at home. The wounds of low-temperature burns are often small in size but deep in depth, and can be easily misdiagnosed as superficial burns. However, most low-temperature burn wounds require surgical treatment. The study also suggests that based on the characteristics and aetiology of low-temperature burns, targeted prevention and treatment measures should be mapped out.