Objectives The value of radial displacement (RD) by speckle tracking echocardiography in locating target coronary artery disease has not been able to determine. We hypothesised that the myocardial RD by speckle tracking echocardiography during rest status could be used in locating target coronary artery and would be better compared to radial strain (RS).
Methods Study population composited of 31 patients with first ST elevated myocardial infarction after primary percutaneous coronary intervention (PCI). Men 26, mean age 63 ± 10 years. The time between onsets to treatment was 5.7 ± 2.0 hours. The lesion involved the left anterior descending artery (LAD) in 17 patients, left circumflex artery (LCX) in 4 patients and right coronary artery (RCA) 10 patients. Speckle tracking echocardiography was performed within 72 hours after PCI during rest status. Myocardial RDs and radial strain 17 myocardial segments were measured by an Echo-PAC computer workstation for automatic function imaging.
Results The territorial coronary arteries had been successfully recanalised in all patients. The AUCs of RD to predict LAD, LCX and RCA were significantly greater compared to RS (0.85- 1.0 vs 0.6- 0.87 for LAD, 0.85–0.94 vs 0.79–0.81 for LCX and 0.86 vs 0.55). The sensitivity and specificity of RD in relative segments to predict LAD, LCX and RCA were higher compared to RS. The sensitivity and specificity of RD in anterior septum at the papillary muscle level and apical level to predict LAD were 100% and 93- 100%, respectively. The sensitivity and specificity of RD in inferior lateral wall at the basal level to predict LCX was 100% and 89%, respectively. The sensitivity and specificity of RD in inferior wall to predict RCA was 90% and 81%, respectively.
Conclusions RD by speckle tracking echocardiography is a novel index to locate target coronary artery and is much better compared to RS.