[Mechanisms of exercise intolerance in patients with heart failure and preserved ejection fraction. Part II: The role of right heart chambers, vascular system and skeletal muscles].

The main clinical manifestation of heart failure with preserved ejection fraction is poor exercise tolerance. In addi-tion to the dysfunction of the left heart chambers, which were presented in the first part of this review, many other disorders are involved in poor exercise tolerance in such patients: impairments of the right heart, vascular system and skeletal muscle. The second part of this review presents the mechanisms for the development of these disorders, as well as possible ways to correct them.

[Mechanisms of exercise intolerance in patients with heart failure and preserved ejection fraction. Part I: The role of impairments in the left heart chambers].

During exercise an increase in oxygen delivery to working muscles is achieved through well‑coordinated interaction of many organs and systems: the heart, lungs, blood vessels, skeletal muscles, and the autonomic nervous system. In heart failure with preserved left ventricular ejection fraction, all mechanisms involved in the normal exercise tolerance are impaired. In the first part of this review, the impairments of the left heart chambers are considered ‑ left ventricular diastolic dysfunction, the weakening of the contractile and chronotropic reserves, left atrium dysfunction; the possible ways of their medical correction are also presented.