High frame rate cardiac cine MRI for the evaluation of diastolic function and its direct correlation with echocardiography

Abstract

Background: Breath-hold cine MR is the method of choice for evaluating left ventricular (LV) systolic function; however, the evaluation of diastolic function remains in the domain of high frame rate echocardiography. Thus, a cine MR technique for simultaneously evaluating LV systolic and diastolic function would be clinically valuable.

Purpose: To test the feasibility of extracting indices that characterize LV diastolic function from high frame rate cine MR.

Study type: Single center, prospective.

Population: Asymptomatic volunteers (N = 24; age 45.8 ± 12.3 years).

Field strength/sequence: High frame rate (70 fps) cine MR and phase-contrast MR during free breathing were acquired at 1.5T.

Assessment: The following MR-based LV filling metrics were extracted from LV volume changes during the cardiac cycle: 1) the volume-rate ratio, R_EFP /R_LFP (ratio of the peak LV filling rate during the early filling period [EFP] to that during the late filling period [LFP]); and 2) the volume ratio, V_EFP /V_LFP (the ratio of cumulative LV volume change between the EFP and LFP). These metrics were then compared with traditional transmitral blood flow-based MR and echocardiographic indices. The effect of temporal resolution on these metrics was also evaluated.

Statistical tests: Bland-Altman and linear regression analyses were used to evaluate the performance of the proposed metrics against traditional indices of diastolic function.

Results: The R_EFP /R_LFP and V_EFP /V_LFP correlated well with E/A_Q-flow (r ² = 0.66 and 0.54, respectively) and E/A_echo (r ² = 0.58 and 0.49, respectively). Systolic indices remained robust (<3% error) for frame rates ≥20 fps. Although the proposed V_EFP /V_LFP was robust (<5% error) up to 25 fps, the proposed volume-rate diastolic function metrics were less reliable (>8% error) for frame rates below 35 fps.

Data conclusion: In asymptomatic volunteers, cardiac cine MR images acquired at frame rates >35 fps can be used to extract LV diastolic function indices from the temporal changes in LV volume.

Level of evidence: 1 Technical Efficacy Stage: 1 J. Magn. Reson. Imaging 2019;50:1571-1582.

Keywords: SSFP; diastolic function; echocardiography; magnetic resonance imaging; phase contrast; systolic function.