Duration of myocardial early systolic lengthening for diagnosis of coronary artery disease

OBJECTIVE: Myocardial early systolic lengthening (ESL) duration is prolonged in patients with coronary artery disease (CAD). However, the relationship between the fractional flow reserve (FFR), the current gold standard for evaluating physiological myocardial ischaemia, and ESL has not been studied. The aims of this study were to investigate whether left ventricular (LV) ESL duration could identify patients with CAD, and to examine the relationship between FFR and LV ESL duration. METHODS: In this single-centre, cross-sectional, prospective study of 75 patients with suspected or known CAD, we performed two-dimensional speckle tracking echocardiography at rest on the day before coronary angiography or percutaneous coronary intervention. Apical 3 views were used to examine ESL duration, defined as time from onset of the Q wave to maximum myocardial systolic lengthening. RESULTS: Thirty-five patients had non-significant stenosis. Forty patients with CAD underwent FFR testing: 17 had an FFR≥0.8 and 23 had an FFR<0.8. Global ESL duration was 20.9±22.2 ms in patients with non-significant stenosis, 36.4±23.2 ms in patients with FFR≥0.8 and 39.6±29.5 ms in patients with FFR<0.8 (p=0.020). However, global and regional ESL durations were not significantly correlated with FFR and demonstrated poor reproducibility. CONCLUSION: Although myocardial ESL duration was significantly prolonged in patients with CAD compared with patients without CAD, ESL at rest showed poor reproducibility, and this new parameter did not predict FFR in patients with suspected CAD.