Page 143 - The role of advanced echocardiography in patients with ischemic heart disease - Rachid Abou

Finally, we observed no correlation between traditional echocardiographic parameters such as LVEF and LVMD. However, more impaired LV GLS was correlated with more prolonged LVMD. These findings were similar to previous studies examining the determinants of LVMD by STE in various patient populations including healthy volunteers.20,24 LVMD may be prolonged in case of increased fibrosis or LV systolic dysfunction, therefore LV GLS is better correlated to LVMD as LV GLS is a more sensitive marker of LV systolic function than LVEF.33,34,35
Left ventricular mechanical dispersion and prognosis after myocardial infarction
Previous studies have reported on the value of LVMD in the risk stratification of
patients post-myocardial infarction.4,6,7,18,19 A recent meta-analysis including 12 studies
and 3198 patients has showed that each 10 ms increment of LVMD was significantly
and independently associated with ventricular arrhythmic events (hazard ratio: 1.19;
95% confidence interval: 1.09 to 1.29; p < 0.01).36 This meta-analysis is also interesting
because it compared the prognostic value of LVMD with that of LVEF and LV GLS.
While each increment in 1 standard deviation of LVEF was significantly associated 7 with less risk of ventricular arrhythmias, LV GLS was not significantly associated with
the events. Therefore, the authors concluded that LVMD had incremental prognostic value of LV GLS. However, it should be acknowledged that the meta-analysis included rather heterogeneous populations (STEMI patients, patients with non-ischemic cardiomyopathy, patients with ischemic cardiomyopathy undergoing ventricular tachycardiac ablation), with wide range of LVMD cut-off values associated with the outcome (from 47 ms to 101.2 ms) and did not test all-cause mortality. In contrast, the present study evaluated the association between LVMD and all-cause mortality. To the best of our knowledge, there this is the first study evaluating the association between LVMD and all-cause mortality in STEMI patients. Kvisvik and colleagues 37 showed in 160 patients with stable coronary artery disease that LVMD was independently associated with all-cause mortality. In contrast, LVEF or LV GLS were not independently associated.
Our study provides more evidence in a large homogenous STEMI population treated according current guidelines.1,2 Furthermore, we provide new information on the correlates of LVMD and expands into knowledge of the association between LVMD and all-cause mortality. This is important because current analysis software provide the measurement of LV GLS and LVMD and the physician could be informed of prolonged LVMD which could be shortened by treating cardiovascular risk factors such as systolic blood pressure or diabetes more effectively. However, the impact of such
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