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ObjectivesThe aim of this study was to determine if strain rate imaging (SRI) correlates with the transmural extent of myocardial infarction (MI) measured by contrast-enhanced magnetic resonance imaging (Ce-MRI).BackgroundIdentification of the transmural extent of myocardial necrosis and degree of non-viability after acute MI is clinically important.MethodsTissue Doppler echocardiography with SRI and Ce-MRI were performed in 47 consecutive patients with a first acute MI between days 2 and 6 and compared to 60 age-matched healthy volunteers. Peak myocardial velocities and peak myocardial deformation strain rates were measured. Location and size of the infarct zone was confirmed by Ce-MRI using the delayed enhancement technique with a 16-segment model.ResultsContrast-enhanced MRI identified transmural infarction in 21 patients, non-transmural infarction in 15 (mean transmurality of infarct 72.3 ± 10.6%), and another 11 patients with subendocardial infarction (−0.59 s−1detected a transmural infarction with high sensitivity (90.9%) and high specificity (96.4%), and −0.98 s−1>SRs >−1.26 s−1distinguished subendocardial infarction from normal myocardium with a sensitivity of 81.3% and a specificity of 83.3%.ConclusionsPeak myocardial deformation by SRI can differentiate transmural from non-transmural MI, and it allows noninvasive determination of transmurality of the scar after MI and thereby the extent of non-viable myocardium.

ObjectivesThe present study aimed to examine whether diastolic and systolic asynchrony exist in diastolic heart failure (DHF) and their prevalence and relationship to systolic heart failure (SHF) patients.BackgroundFew data exist on mechanical asynchrony in DHF.MethodsTissue Doppler echocardiography was performed in 373 heart failure patients (281 with SHF and 92 with DHF) and 100 normal subjects. Diastolic and systolic asynchrony was determined by measuring the standard deviation of time to peak myocardial systolic (Ts-SD) and peak early diastolic (Te-SD) velocity using a 6-basal, 6-mid-segmental model, respectively.ResultsBoth heart failure groups had prolonged Te-SD (DHF vs. SHF vs. controls subjects: 32.2 ± 18.0 ms vs. 38.0 ± 25.2 ms vs. 19.5 ± 7.1 ms) and Ts-SD (31.8 ± 17.0 ms vs. 36.7 ± 15.2 ms vs. 17.6 ± 7.9 ms) compared with the control group (all p < 0.001 vs. control subjects). Based on normal values, the DHF group had comparable diastolic (35.9% vs. 43.1%; chi-square = 1.48, p = NS), but less systolic asynchrony than the SHF group (39.1% vs. 56.9%; chi-square = 8.82, p = 0.003). Normal synchrony, isolated systolic, isolated diastolic, and combined asynchrony were observed in 39.1%, 25.0%, 21.7%, and 14.1% of DHF patients, respectively, and these were 25.6%, 31.3%, 17.4%, and 25.6%, correspondingly, in SHF (chi-square = 10.01, p = 0.019). The correlation between systolic and diastolic asynchrony, and between the myocardial velocities and corresponding mechanical asynchrony appeared weak. A wide QRS duration (>120 ms) was rare in DHF (10.9% vs. 37.7% in SHF) (chi-square = 16.69, p < 0.001).ConclusionsDiastolic and/or systolic asynchrony was common in 61% of DHF patients despite narrow QRS complex. The presence of asynchrony was not related to myocardial systolic or diastolic function. Systolic and diastolic asynchrony were not tightly coupled, implying distinct mechanisms.