Pressure-volume loop analysis in heart failure with preserved ejection fraction: Implications for cardiac mechanics, diagnosis, and treatment strategy.

Heart failure with preserved ejection fraction (HFpEF), previously referred to as diastolic heart failure, accounts for more than half of heart failure hospitalizations in patients over 65 years of age. Although the prevalence of heart failure with reduced ejection fraction has declined, HFpEF is increasingly prevalent in Japan and worldwide. Traditionally, HFpEF was primarily thought to be caused by diastolic dysfunction, characterized by impaired left ventricular (LV) relaxation and increased LV stiffness. Analysis of LV pressure-volume (PV) loop is an invasive method that allows for the simultaneous and detailed evaluation of intrinsic LV systolic and diastolic function, as well as effective arterial elastance (Ea). LV systolic function is assessed by end-systolic elastance, derived from end-systolic PV relations, while diastolic stiffness is evaluated by LV stiffness constant (β), determined from the slope of the end-diastolic pressure-volume relation. Ea, representing LV afterload, is calculated as end-systolic pressure divided by stroke volume. Furthermore, PV loop analysis provides insights into LV mechanics through measurements of stroke work, PV area, and ventricular-arterial coupling. These parameters enable clinicians to more precisely characterize the mechanical properties of the LV than conventional echocardiography or imaging modalities. In HFpEF, where accurate assessments of LV function and hemodynamics is essential, understanding PV loop data provides valuable insight into the pathophysiology of HFpEF. PV loop analysis has the potential to facilitate in-depth assessment and monitoring of treatment strategies. In this review, we introduce LV PV loop analysis in our patients with HFpEF and explore its correlation with PV loop parameters obtained from the other imaging modalities, such as echocardiography and cardiac magnetic resonance imaging. By highlighting the clinical relevance of PV loop analysis, we aim to advance therapeutic decision-making and promote a personalized approach in this heterogenous HFpEF population.