Material:
67 patients (12 female) with a multi-vessel coronary artery disease and a history of a myocaridal infarction and low EF were referred for CMR and 2DECHO.
The patients’ data are summarized in Figure 1.
The exclusion criteria were arrhythmia and/or contraindications to CMR.
Patients with clinically significant aortic valve disease,
mitral stenosis and non-ischemic mitral regurgitation were excluded from the analysis.
The period of time between CMR and 2DECHO was 5 ± 2 days.
CMR protocol
CMR studies were performed using a 1,0 T MR Unit (Magnetom Harmony,
Siemens) with following parameters: magnetic gradients amplitude: 40mT,
slew rate 200mT/m/s,
dedicated four-element phase-array receiver coil.
Examination protocol consisted of SE/T1 weighted sequence,
‘dark blood’ images in the axial plane and TruFISP cine ECG gated sequence in 2-chamber,
4-chamber and short axis views.
Figure 2 Parameters of TruFisp cine sequence are presented in Figure 3.
The parameters of systolic left ventricle function: EDVi and ESVi, EF and LV mass index (LVMi) were calculated n dedicated workstation (Leonardo,
Siemens).
Endocardial and epicardial contours were manually drawn on short-axis images by a single operator,
unaware of the 2DECHO results.
Papillary muscles and endocardial trabeculations were excluded from LV mass.
Basal slices with an incomplete muscular ring of less then 75%,
were
omitted as 'atrial'.
2D ECHO protocol
2DECHO exams were performed using a Sonos 7500 scanner,
coupled with a 2.5 MHz sector transducer (Philips Medical System).
EDVi,
ESVi and EF were obtained by the biplane Simpson’s method Figure 4.
Calculation of the LV mass was performed using the area-length method Figure 5.
Statistical analysis
The correlation between the measures in 2DECHO and CMR was evaluated using Pearson’s correlation coefficient and the coefficient of determinantion (R2).
The relationship between variables was confirmed with a linear regression analysis.
The between-method comparison was done with Bland-Altman analysis.
Linear regression equation was used to evaluate whether the differences are dependent on the magnitude of measurements.
The results of the statistical tests were considered as statistically significant with p<0.05.
The statistical analysis was performed by means of MedCalc 11.1.1.0 (MedCalc,
Belgium).