Recommendations for the Evaluation of Left Ventricular Diastolic Function by Echocardiography

Abstract

The assessment of left ventricular (LV) diastolic function should be an integral part of a routine examination, particularly in patients presenting with dyspnea or heart failure. About half of patients with new diagnoses of heart failure have normal or near normal global ejection fractions (EFs). These patients are diagnosed with “diastolic heart failure” or “heart failure with preserved EF.” 1 The assessment of LV diastolic function and filling pressures is of paramount clinical importance to distinguish this syndrome from other diseases such as pulmonary disease resulting in dyspnea, to assess prognosis, and to identify underlying cardiac disease and its best treatment. LV filling pressures as measured invasively include mean pulmonary wedge pressure or mean left atrial (LA) pressure (both in the absence of mitral stenosis), LV end-diastolic pressure (LVEDP; the pressure at the onset of the QRS complex or after A-wave pressure), and pre-A LV diastolic pressure (Figure 1 ).Although these pressures are different in absolute terms, they are closely related, and they change in a predictable progression with myocardial disease, such that LVEDP increases prior to the rise in mean LA pressure. The 4 phases of diastole are marked in relation to high-fidelity pressure recordings from the left atrium (LA) and left ventricle (LV) in anesthetized dogs. The first pressure crossover corresponds to the end of isovolumic relaxation and mitral valve opening. In the first phase, left atrial pressure exceeds left ventricular pressure, accelerating mitral flow. Peak mitral E roughly corresponds to the second crossover. Thereafter, left ventricular pressure exceeds left atrial pressure, decelerating mitral flow. These two phases correspond to rapid filling. This is followed by slow filling, with almost no pressure differences. During atrial contraction, left atrial pressure again exceeds left ventricular pressure. The solid arrow points to left ventricular minimal pressure, the dotted arrow to left ventricular pre-A pressure, and the dashed arrow to left ventricular end-diastolic pressure. The upper panel was recorded at a normal end-diastolic pressure of 8 mm Hg. The lower panel was recorded after volume loading and an end-diastolic pressure of 24 mm Hg. Note the larger pressure differences in both tracings of the lower panel , reflecting decreased operating compliance of the LA and LV. Atrial contraction provokes a sharp rise in left ventricular pressure, and left atrial pressure hardly exceeds this elevated left ventricular pressure. (Courtesy of T. C. Gillebert and A. F. Leite-Moreira.) Echocardiography has played a central role in the evaluation of LV diastolic function over the past two decades. The purposes of this document is to provide a comprehensive review of the techniques and the significance of diastolic parameters, as well as recommendations for nomenclature and reporting of diastolic data in adults. The recommendations are based on a critical review of the literature and the consensus of a panel of experts. The optimal performance of the left ventricle depends on its ability to cycle between two states: (1) a compliant chamber in diastole that allows the left ventricle to fill from low LA pressure and (2) a stiff chamber (rapidly rising pressure) in systole that ejects the stroke volume at arterial pressures. The ventricle has two alternating functions: systolic ejection and diastolic filling. Furthermore, the stroke volume must increase in response to demand, such as exercise, without much increase in LA pressure. 2 The theoretically optimal LV pressure curve is rectangular, with an instantaneous rise to and an instantaneous to low diastolic allows for the for LV filling. This theoretically optimal is by the of and mitral and at valve and LV pressure rapid filling, heart and atrial 2 filling pressures are the of diastolic 2 pressures are elevated the mean pulmonary wedge pressure is mm or the LVEDP is mm Hg. 1 pressures change with in of filling pressures and diastolic LV filling pressures are by filling and of the LV be by myocardial relaxation and in diastolic myocardial the the of to a contraction and relaxation is the the after contraction to its and In normal and with normal myocardial relaxation is at minimal LV pressure. and relaxation to the of of the and are closely is to by and 2 or systolic myocardial with elevated to filling pressures. 4 to the underlying from the and and is by a of that 2 and of the of contraction and relaxation is relaxation in a between in and of other and to global LV relaxation and elevated filling pressures. The of global LV myocardial relaxation is by the of LV pressure a to a pressure is a of the of LV be at a to after is 1 In the of relaxation be in of LV and with the relaxation or the between valve and mitral valve opening. LV filling is by the between LV filling pressures and filling These filling are with or with compliance and to end-diastolic and to the left ventricl