Automated quantitative assessment of cardiovascular magnetic resonance-derived atrioventricular junction velocities.

The assessment of atrioventricular junction (AVJ) deformation plays an important role in evaluating left ventricular systolic and diastolic function in clinical practice. This study aims to demonstrate the effectiveness and consistency of cardiovascular magnetic resonance (CMR) for quantitative assessment of AVJ velocity compared with tissue Doppler echocardiography (TDE). A group of 145 human subjects comprising 21 healthy volunteers, 8 patients with heart failure, 17 patients with hypertrophic cardiomyopathy, 52 patients with myocardial infarction, and 47 patients with repaired Tetralogy of Fallot were prospectively enrolled and underwent TDE and CMR scan. Six AVJ points were tracked with three CMR views. The peak systolic velocity (Sm1), diastolic velocity during early diastolic filling (Em), and late diastolic velocity during atrial contraction (Am) were extracted and analyzed. All CMR-derived septal and lateral AVJ velocities correlated well with TDE measurements (Sm1: r = 0.736; Em: r = 0.835; Am: r = 0.701; Em/Am: r = 0.691; all p < 0.001) and demonstrated excellent reproducibility [intrastudy: r = 0.921-0.991, intraclass correlation coefficient (ICC): 0.918-0.991; interstudy: r = 0.900-0.970, ICC: 0.887-0.957; all p < 0.001]. The evaluation of three-dimensional AVJ motion incorporating measurements from all views better differentiated normal and diseased states [area under the curve (AUC) = 0.918] and provided further insights into mechanical dyssynchrony diagnosis in HF patients (AUC = 0.987). These findings suggest that the CMR-based method is feasible, accurate, and consistent in quantifying the AVJ deformation, and subsequently in diagnosing systolic and diastolic cardiac dysfunction.

Left ventricular diastolic function assessment using time differences between mitral annular velocities and transmitral inflow velocities in patients with heart failure.

BACKGROUND: Evaluation of left ventricular (LV) diastolic function is important in clinical echocardiography. The relationship between mitral annular velocities and transmitral inflow velocities provide additional information about LV filling and diastolic function. This study evaluates the relationships of time intervals between peaks E of mitral inflow velocities and E' of mitral annular velocities, and peaks A and A' in patients with heart failure (HF). METHODS: Eighty patients with HF and 50 age- and gender-matched normal healthy subjects were prospectively recruited and underwent full echocardiograms. The following time intervals were measured: (1) from the onset of R-wave on the ECG to the peak of E-wave on the transmitral flow (TMF) (R-pE); (2) from R to peak of E'-wave on the LV lateral wall of tissue Doppler imaging (TDI) (R-pE'); (3) from onset of P-wave to peak of A-wave on the TMF (P-pA); and (4) from onset of P-wave to peak of A'-wave (P-pA') of TDI. Early-diastolic temporal discordance (EDTD) and late-diastolic temporal discordance (LDTD) were calculated as the difference between the time intervals (R-E) and (R-E'), (P-pA) and (P-p A'). RESULTS: EDTD significantly decreased in patients with HF compared with normal subjects (18.0±54.1ms vs. 28.0±33.5ms, P<0.05). There was also a significant decrease in LDTD in HF patients compared with normal subjects (19.6±23.5ms vs. 34.8±20.6; P<0.05). CONCLUSIONS: EDTD and LDTD decreased in patients with heart failure, and they may be useful tools in identifying abnormal LV relaxation and left atrial contraction for LV diastolic function.