Qualitative Assessment of Color M-Mode Signals in the Evaluation of Left Ventricular Diastolic Function: A Proof of Concept Study

Objectives: Although the most recent American Society of Echocardiography guidelines are a major step forward in echocardiographic evaluation of diastolic function, the ability to differentiate between normal and abnormal function remains challenging. The authors aimed to determine whether qualitative assessments of color M-mode flow displays could be a useful parameter in the evaluation of left ventricular (LV) diastolic dysfunction. Design: Retrospective observational study. Setting: Tertiary care level hospital. Participants: The study comprised echocardiographic data from 105 consecutive patients. Intervention: None. Measurements and Main Results: Patients were allocated into the following 3 groups according to the LV diastolic function based on current American Society of Echocardiography recommendation guidelines for LV diastolic dysfunction classification: group I—normal function (n = 40); group II—early relaxation abnormalities (grade I) (n = 50), and group III—elevated LV pressures (grade II) (n = 15). Patients with normal diastolic function were younger (45 ± 14 y) than those with diastolic dysfunction (group II: 64 ± 10 y and group III: 56 ± 15 y) (p < 0.05). Volumetric echocardiographic parameters and mitral inflow and mitral annulus tissue Doppler imaging measures were significantly different among the 3 studied groups (p < 0.05). Interestingly, qualitative assessment of color M-mode flows displayed distinctive signals based on the left ventricle filling properties. Intraobserver and interobserver variability to determine the reliability of these signals were robust (weighted kappa 0.84 ± 0.11 and 0.65 ± 0.13, respectively). Conclusion: Qualitative assessment of color M-mode flow displays offers simple and reliable information of potential usefulness in the evaluation of LV diastolic function.