Heart failure (HF) is a major public health issue worldwide with increased prevalence and a high number of hospitalizations. Patients with chronic HF and either reduced ejection fraction (HFrEF) or mildly reduced ejection fraction (HFmrEF) present vascular endothelial dysfunction and significantly decreased circulating levels of endothelial progenitor cells (EPCs). EPCs are bone marrow-derived cells involved in endothelium regeneration, homeostasis, and neovascularization. One of the unsolved issues in the field of EPCs is the lack of an established method of identification. The most widely approved method is the use of monoclonal antibodies and fluorescence-activated cell sorting (FACS) analysis via flow cytometry. The most frequently used markers are CD34, VEGFR-2, CD45, CD31, CD144, and CD146. Exercise training has demonstrated beneficial effects on EPCs by increasing their number in peripheral circulation and improving their functional capacities in patients with HFrEF or HFmrEF. There are two potential mechanisms of EPCs mobilization: shear stress and the hypoxic/ischemic stimulus. The combination of both leads to the release of EPCs in circulation promoting their repairment properties on the vascular endothelium barrier. EPCs are important therapeutic targets and one of the most promising fields in heart failure and, therefore, individualized exercise training programs should be developed in rehabilitation centers.

Spontaneous coronary artery dissection (SCAD) is a rare non-atherosclerotic cause of acute coronary syndromes defined as non-iatrogenic, non-traumatic separation of the coronary artery wall. The most common profile is a middle-aged woman between 44 and 53 years with few cardiovascular risk factors. SCAD is frequently linked with predisposing factors, such as postpartum, fibromuscular dysplasia or other vasculopathies, connective tissue disease and hormonal therapy, and it is often triggered by intense physical or emotional stress, sympathomimetic drugs, childbirth and activities increasing shear stress of the coronary artery walls. Patients with SCAD usually present at the emergency department with chest discomfort, chest pain, and rapid heartbeat or fluttery. During the last decades, the most common problem of SCAD was the lack of awareness about this condition which has led to significant underdiagnosis and misdiagnosis. However, modern imaging techniques such as optical coherence tomography, intravascular ultrasound, coronary angiography or magnetic resonance imaging have contributed to the early diagnosis of the disease. Treatment of SCAD remains controversial, especially during the last years, where invasive techniques are being used more often and in more emergent cardiac syndromes. Although conservative treatment combining aspirin and beta-blocker remains the recommended strategy in most cases, revascularization could also be suggested as a method of treatment in specific indications, but with a higher risk of complications. The prognosis of SCAD is usually good and long-term mortality seems to be low in these patients. Follow-up should be performed on a regular basis.

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