Insuficiência cardíaca com fração de ejeção normal: novos critérios diagnósticos e avanços fisiopatológicos

Abstract

Heart failure (HF) is a highly prevalent complex cardiovascular syndrome, and its clinical presentation is usually associated with ventricular dilatation, decreased contractility and reduced left ventricular ejection fraction (EF). However, in the past two decades studies have demonstrated that many patients with signs and symptoms of HF have normal EF (higher than 50%). The great challenge for doctors lies in the identification of patients presenting heart failure with normal ejection fraction (HFNEF) and this challenge seems to be mainly related to the high complexity of the syndrome and to the lack of a standardized method to confirm or exclude the diagnosis that could be used in the daily clinical practice. Unlike in heart failure with reduced ejection fraction (HFREF) in which one single parameter - EF lower than 50%, is sufficient to confirm the diagnosis of the syndrome, in HFNEF different diastolic indexes have been used to characterize the presence or absence of diastolic dysfunction (DD). The purpose of this review is to show new concepts related to the diastolic function that will help understand the cardiovascular pathophysiology of HFNEF, and to discuss the new guideline of the European Society of Cardiology for the diagnosis and exclusion of HFNEF based on cardiac function indices obtained using tissue Doppler imaging (TDI) and natriuretic peptide determination.

Entendendo a disfunção diastólica assintomática na prática clínica

“…The mechanical process of diastole can be divided into an active phase called relaxation and a passive phase called stiffness; the ventricular filling in its initial phase, which corresponds to 70% of the process, is carried out by the phenomenon of diastolic suction, which depends on relaxation 29 .…”

Increased cardiovascular risk in rats with primary renal dysfunction; mediating role for vascular endothelial function

“…However, in a substantial proportion of cardiorenal disease patients, cardiac dysfunction is characterized by diastolic rather than systolic dysfunction; heart failure with preserved ejection fraction [29, 32]. Data from the present study indicate that rats with CRD may display diastolic heart failure indicated by stronger reduction in cardiac output at similar ejection fraction, increased E/e ’ ratio and signs of congestion.…”

Systems Biology Applied to Heart Failure With Normal Ejection Fraction

“…Its pathophysiology has been mainly centered on the presence of left ventricular (LV) structural and diastolic functional changes, which cause an increase in LV filling pressures and intolerance to physical exertion 2-4 .…”

“…Although patients with HFNEF have LV ejection fraction values considered normal, they have changes in systolic performance, which can be assessed through different systolic function indices, such as LV contractility, systolic volume, cardiac output and axial systolic shortening velocity (S'). Abnormality of relaxation and increased ventricular stiffness lead to increased LV filling pressures, which are diastolic dysfunction markers 2 .…”