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Heart failure (HF) is a clinical syndrome consisting of typical symptoms and signs due to structural and/or functional abnormalities of the heart, resulting in elevated intracardiac pressures and/or inadequate cardiac output. The vascular system plays a crucial role in the development and progression of HF regardless of ejection fraction, with endothelial dysfunction (ED) as one of the principal features of HF. The main ED manifestations (i.e., impaired endothelium-dependent vasodilation, increased oxidative stress, chronic inflammation, leukocyte adhesion, and endothelial cell senescence) affect the systemic and pulmonary haemodynamic and the renal and coronary circulation. The present review is aimed to discuss the contribution of ED to HF pathophysiology—in particular, HF with preserved ejection fraction—ED role in HF patients, and the possible effects of pharmacological and non-pharmacological approaches. For this purpose, relevant data from a literature search (PubMed, Scopus, EMBASE, and Medline) were reviewed. As a result, ED, assessed via venous occlusion plethysmography or flow-mediated dilation, was shown to be independently associated with poor outcomes in HF patients (e.g., mortality, cardiovascular events, and hospitalization due to worsening HF). In addition, SGLT2 inhibitors, endothelin antagonists, endothelial nitric oxide synthase cofactors, antioxidants, and exercise training were shown to positively modulate ED in HF. Despite the need for future research to better clarify the role of the vascular endothelium in HF, ED represents an interesting and promising potential therapeutic target.

Heart failure with preserved ejection fraction (HFpEF) represents the most common HF phenotype of patients aged > 65 years, with an incidence and a prevalence that are constantly growing. The HFpEF cardinal symptom is exercise intolerance (EI), defined as the impaired ability to perform physical activity and to reach the predicted age-related level of exercise duration in the absence of symptoms—such as fatigue or dyspnea—and is associated with a poor quality of life, a higher number of hospitalizations, and poor outcomes. The evidence of the protective effect between exercise and adverse cardiovascular outcomes is numerous and long-established. Regular exercise is known to reduce cardiovascular events and overall mortality both in apparently healthy individuals and in patients with established cardiovascular disease, representing a cornerstone in the prevention and treatment of many cardio-metabolic conditions. Several studies have investigated the role of exercise in HFpEF patients. The present review aims to dwell upon the effects of exercise on HFpEF. For this purpose, the relevant data from a literature search (PubMed, EMBASE, and Medline) were reviewed. The analysis of these studies underlines the fact that exercise training programs improve the cardiorespiratory performance of HFpEF patients in terms of the increase in peak oxygen uptake, the 6 min walk test distance, and the ventilatory threshold; on the other hand, diastolic or systolic functions are generally unchanged or only partially modified by exercise, suggesting that multiple mechanisms contribute to the improvement of exercise tolerance in HFpEF patients. In conclusion, considering that exercise training programs are able to improve the cardiorespiratory performance of HFpEF patients, the prescription of exercise training programs should be encouraged in stable HFpEF patients, and further research is needed to better elucidate the pathophysiological mechanisms underpinning the beneficial effects described.

Nontuberculous mycobacteria (NTM) identification is essential for establishing the relevance of the isolate and for appropriate antimicrobial therapy. Traditionally, NTM identification is performed by using Line Probe Assays (LPA), a costly and time-consuming technique requiring trained personnel. MALDI-TOF MS is a promising tool for NTM identification, and its use is rapidly growing. We evaluated the newly introduced MBT Mycobacteria kit (MBT) and the MycoEx preparation protocol (Bruker Daltonics, Germany) for NTM MALDI-TOF MS identification using LPA results as a reference. Fifty NTM grown on 7H11 agar and MGIT broth were analyzed with both protocols using the Bruker Microflex® LT MALDI-TOF MS (Bruker Daltonics) instrument. MBT and MycoEx provided identification results in 97.0% and 95.0% of the cases, respectively. With both protocols, 100% of the provided results agreed with LPA with no registered mismatch. MBT achieved an elevated number of highly probable identifications (88.0% vs. 83.0%) and a higher reproducibility rate of correct results (86.6% vs. 75.8%) in comparison to MycoEx. This study provides results about MBT performance for liquid and solid media, underlining the strengths and weakness under different conditions. Our results suggest that MALDI-TOF MS could provide a great advantage for timely and cost-saving NTM identification with potential implications for patient outcome.