No abstract

Heart failure (HF) frequently coexists with conditions associated with glucose insufficiency, such as insulin resistance and type 2 diabetes mellitus (T2DM), and patients with T2DM have a significantly high incidence of HF. These two closely related diseases cannot be separated on the basis of their treatment. Some antidiabetic drugs failed to improve cardiac outcomes in T2DM patients, despite lowering glucose levels sufficiently. This may be, at least in part, due to a lack of understanding of cardiac insulin resistance. Basic investigations have revealed the significant contribution of cardiac insulin resistance to the pathogenesis and progression of HF; however, there is no clinical evidence of the definition or treatment of cardiac insulin resistance. Mitochondrial dynamics play an important role in cardiac insulin resistance and HF because they maintain cellular homeostasis through energy production, cell survival, and cell proliferation. The innovation of diagnostic tools and/or treatment targeting mitochondrial dynamics is assumed to improve not only the insulin sensitivity of the myocardium and cardiac metabolism, but also the cardiac contraction function. In this review, we summarized the current knowledge on the correlation between cardiac insulin resistance and progression of HF, and discussed the role of mitochondrial dynamics on the pathogenesis of cardiac insulin resistance and HF. We further discuss the possibility of mitochondria-targeted intervention to improve cardiac metabolism and HF.

Background The burden of noncardiovascular conditions is becoming increasingly prevalent in patients with heart failure (HF). We aimed to identify novel phenogroups incorporating noncardiovascular conditions to facilitate understanding and risk stratification in elderly patients with HF. Methods and Results Data from a total of 1881 (61.2%) patients aged ≥65 years were extracted from a prospective multicenter registry of patients hospitalized for acute HF (N=3072). We constructed subgroups of patients with HF with preserved ejection fraction (HFpEF; N=826, 43.9%) and those with non‐HFpEF (N=1055, 56.1%). Latent class analysis was performed in each subgroup using 17 variables focused on noncardiovascular conditions (including comorbidities, Clinical Frailty Scale, and Geriatric Nutritional Risk Index). The latent class analysis revealed 3 distinct clinical phenogroups in both HFpEF and non‐HFpEF subgroups: (1) robust physical and nutritional status (Group 1: HFpEF, 41.2%; non‐HFpEF, 46.0%); (2) multimorbid patients with renal impairment (Group 2: HFpEF, 40.8%; non‐HFpEF, 41.9%); and (3) malnourished patients (Group 3: HFpEF, 18.0%; non‐HFpEF, 12.1%). After multivariable adjustment, compared with Group 1, patients in Groups 2 and 3 had a higher risk for all‐cause death over the 1‐year postdischarge period (hazard ratio [HR], 2.79 [95% CI, 1.64–4.81] and HR, 2.73 [95% CI, 1.39–5.35] in HFpEF; HR, 1.96 [95% CI, 1.22–3.14] and HR, 2.97 [95% CI, 1.64–5.38] in non‐HFpEF; respectively). Conclusions In elderly patients with HF, the phenomapping focused on incorporating noncardiovascular conditions identified 3 phenogroups, each representing distinct clinical outcomes, and the discrimination pattern was similar for both patients with HFpEF and non‐HFpEF. This classification provides novel risk stratification and may aid in clinical decision making.

Pulmonary vein isolation has become a cornerstone treatment for catheter ablation of atrial fibrillation (AF). Recent reports show that additional ablation targeting low-voltage zones reduces AF recurrence. However, the pre-procedural predictors of low-voltage zones remain elusive. We retrospectively enrolled 359 patients (mean age 63.7 ± 10.8 years; 73 females; and 149 had persistent atrial fibrillation) who underwent catheter ablation for AF and left atrial (LA) voltage mapping during sinus rhythm or atrial pacing. Low-voltage zones were defined as area of > 5 cm2 with a bipolar electrogram amplitude of < 0.50 mV. Overall, 51 (14.2%) patients had low-voltage zones. Patients with low-voltage zones were older (67.9 ± 9.9 vs. 63.0 ± 10.8 years; P = 0.003), predominantly female (33.3% vs. 18.2%; P = 0.013), had higher prevalence of dilated cardiomyopathy (DCM) (11.8% vs. 1.6%; P = 0.002) and hypertrophic cardiomyopathy (HCM) (9.8% vs. 2.6%; P = 0.025), and had larger LA volumes (153.6 ± 46.4 vs. 117.7 ± 67.8 mL; P < 0.001) than those without low-voltage zones. Multivariate logistic regression analysis revealed that age (OR 1.060; 95% CI 1.022–1.101, P = 0.002), female sex (OR 2.978; 95% CI 1.340–6.615, P = 0.007), DCM (OR 8.341; 95% CI 1.381–50.372, P = 0.021), HCM (OR 5.044; 95% CI 1.314–19.363, P = 0.018), persistent AF (OR 4.188; 95% CI 1.928–9.100, P < 0.001), and larger LA volume (OR 3.215; 95% CI 1.378–7.502, P = 0.007) were independently associated with the presence of low-voltage zones. Patient age, female sex, DCM, HCM, persistent AF and larger LA volume may predict the presence of low-voltage zones and could be useful in selecting the appropriate ablation strategy for AF.

Background: Maintaining bioenergetic homeostasis provides a means to reduce the risk of cardiovascular events during chronological aging. Nicotinamide adenine dinucleotide (NAD + ) acts as a signaling molecule, and its levels were used to govern several biological pathways, for example, promoting angiogenesis by SIRT1 (sirtuin 1)-mediated inhibition of Notch signaling to rejuvenate capillary density of old-aged mice. NAD + modulation shows promise in the vascular remodeling of endothelial cells. However, NAD + distribution in atherosclerotic regions remains uncharacterized. Omega-3 polyunsaturated fatty acids consumption, such as docosahexaenoic acid and eicosapentaenoic acid, might increase the abundance of cofactors in blood vessels due to omega-3 polyunsaturated fatty acids metabolism. Methods: Apolipoprotein E-deficient ( ApoE −/− ) mice were fed a Western diet, and the omega-3 polyunsaturated fatty acids-treated groups were supplemented with docosahexaenoic acid (1%, w/w) or eicosapentaenoic acid (1%, w/w) for 3 weeks. Desorption electrospray ionization mass spectrometry imaging was exploited to detect exogenous and endogenous NAD + imaging. Results: NAD + , NADH, NADP + , NADPH, FAD + , FADH, and nicotinic acid adenine dinucleotide of the aortic arches were detected higher in the omega-3 polyunsaturated fatty acids-treated mice than the nontreated control. Comparing the distribution in the outer and inner layers of the arterial walls, only NADPH was detected slightly higher in the outer part in eicosapentaenoic acid-treated mice. Conclusions: Supplementation of adding docosahexaenoic acid or eicosapentaenoic acid to the Western diet led to a higher NAD + , FAD + , and their metabolites in the aortic arch. Considering the pleiotropic roles of NAD + in biology, this result serves as a beneficial therapeutic strategy in the animal model counter to pathological conditions.