Radial versus longitudinal myocardial deformation from gray-scale echocardiography.

The objectives of this work are to evaluate a novel non-Doppler-based echocardiographic method that makes it possible to simultaneously obtain the radial and longitudinal components of myocardial velocity (V) and strain (S), and to assess whether left ventricular fiber architecture affects the net function of the myocardium. Previous reports state that differences in the estimation of regional function between septum and lateral walls can be related to the anatomic disposition of myocardial fibers. In this work we measure and compare in 21 healthy volunteers longitudinal and radial peak systolic velocity V (V(long), V(rad): cm/s), peak systolic strain S (S(long), S(rad): %) and time-to-peak S and V (T-Smax, T-V(max): ms) at the midsegments of the septal and lateral walls. Results show that V was higher, both in the radial and longitudinal components, in the lateral wall than in the septum (V(rad): 4.77 +/- 0.26 cm/s vs. 3.77 +/- 0.20 cm/s, p = 0.007; V(long): 5.60 +/- 0.48 cm/s vs. 4.13 +/- 0.11 cm/s, p = 0.01). Radial strain was higher in the septum (S(rad): 28.63 +/- 2.25% vs. 22.54 +/- 1.5%, p = 0.015), and longitudinal strain, in the lateral wall (S(long): -25.89 +/- 1.43% vs. -22.20 +/- 0.87%, p = 0.02). There was a significant delay in longitudinal T-Smax between the lateral and septal medial segments (mean: 14.5 ms; CI 95%: 0.3-28.6 ms; p = 0.04), with no difference in radial T-Smax (277.1 +/- 8.6 ms vs. 277.2 +/- 12.4 ms, p = 0.93). The assessment of regional myocardial function by this new method enables the simultaneous analysis of its radial and longitudinal components. These measurements correlate well with previous anatomical knowledge of the architecture of myocardial fibers, emphasizing its functional significance in regional myocardial function analysis.

Doppler Tissue Imaging positive preejection velocity wave is a sign of non-transmural necrosis: comparison with delayed-enhancement cardiac magnetic resonance.

AIMS: Our purpose was to test the hypothesis that Tissue Doppler Imaging (TDI)-derived positive preejection velocity (PPV) is associated with transmural extent of necrosis in delayed-enhancement cardio-magnetic resonance (DE-CMR) in patients with reperfused myocardial infarction (MI). METHODS AND RESULTS: Longitudinal myocardial velocities were recorded by TDI in 24 patients with MI reperfused with primary angioplasty, using an Acuson-Sequoia equipment. The same day a CMR study was performed, including cine images in short axis and long axis views and DE images in the same views using a 3D-T1-Turbo-field-echo sequence, 15 min after administration of gadodiamide. Transmural extent of hyperenhancement in each segment was compared to presence or absence of PPV wave. A total of 384 segments were evaluated. Normo-hypokinetic segments (100%) showed a PPV wave, whereas it was only present in 53% of akinetic-dyskinetic segments (p=0.0005). One hundred percent of the segments with absent-mild DE showed a PPV wave; this percentage was lower in segments with intermediate and transmural DE (63 and 10%, p=0.001). The presence of PPV wave in an akinetic segment ruled out transmural necrosis with 97% sensitivity and 90% specificity. CONCLUSIONS: The absence of PPV is strongly associated to transmural necrosis in MI and therefore to absence of viability.