Is universal grading of diastolic function by echocardiography feasible?

Abstract

Quantitation of diastolic function centers on the assessment of active and passive ventricular properties, and involves measurement estimates of ventricular relaxation, and chamber and myocardial stiffness. Diastolic dysfunction is a propensity to develop increased left ventricular (LV) end-diastolic pressure. Recently American Society of Echocardiography and European Association of Cardiovascular Imaging (ASE/EACVI) proposed a new grading system. While the new guidelines are ambiguous and with cutoff points that may misclassify patients as both sicker and healthier than they are. This article outlines the pathophysiology behind the diastolic dysfunction and role and limitation of echocardiographic assessment in predicting LV diastolic dysfunction.

Keywords: Diastolic function; echocardiography; ventricular volume.

Figure 1

Computer simulations of left ventricular and left atrial pressures and volumes, as well as transmitral and transaortic valve velocities. Red lines represent baseline conditions. Yellow line on (A) represents prolongation of relaxation by increase of time constant of isovolumic pressure decay (tau) from 60 to 100 ms. Yellow line on (B) represents doubling of chamber stiffness. LA, left atrium; LV, left ventricular; RV, right ventricle; RA, right atrium; MVF, mitral valve inflow.

Figure 2

Age-related changes in normal values of (A) E' septal, (B) E/E', (C) E/A, and (D) RVSP. Normal values of echocardiographic diastolic function parameter at each age from literature were shown. The dashed lines in each plot indicate the cutoff values mentioned in the latest Recommendations. The cutoff values for RVSP were calculated according to the cutoff value of TR velocity 2.8 m/s with RA pressure 5 mmHg. Thick line indicates mean value reported in each literature and dotted line indicates 95% confidence interval. E', peak early diastolic annular velocities of the mitral annulus by tissue Doppler imaging ; E/E', ratio of the peak early filling [E] velocity of mitral inflow and E' velocity; E/A, ratio of E and late diastolic filling [A] velocities of mitral inflow; RVSP, right ventricular systolic pressure; TR, tricuspid regurgitation; RA, right atrium.

Figure 3

Age histogram of patients with comprehensive echocardiographic study performed at Cleveland Clinic in December 2016 (n=3,720).

Figure 4

Representative images of (A) transmitral inflow, (B) mitral annulus, and (C) tricuspid annulus velocities in a patient 1 and 2 years after successful pulmonary vein isolation for atrial fibrillation. Even with successful treatment in AF, reduced mitral inflow A velocity [A] and mitral annular a' velocity (lateral) [B] persist, suggesting a permanent loss of atrial contraction. AF, atrial fibrillation; PW, pulsed wave; DTI, tissue Doppler imaging.