P4647Role of speckle tracking echocardiography in prediction of late exercise capacity in patients after acute myocardial infarction

Purpose: To establish the early determinants of the late exercise capacity in patients after ST-segment elevation myocardial infarction (STEMI). Methods: We enrolled 60 STEMI patients, who were examined on 7-th day (first visit) and at 6-th month (second visit) after STEMI. We evaluated wall motion score index (WMSI) and left ventricle ejection fraction (LVEF). By the use of speckle-tracking echocardiography (STE) we assessed global longitudinal strain (GLS), global circumferential strain (GCS), global radial strain (GRS), post-systolic strain index (PSSI) and strain delay index (SDI). During the second visit patients were undergone exercise treadmill test (ETT) in order to assess the possibility to perform completely a submaximal ETT. Metabolic equivalent (MET) was used as the indirect index of oxygen uptake. Results: There was a significant correlation between the level of METs at the peak of ETT and resting value of LVEF (r=0.36, p=0.02), GLS (r=0.48, p=0.001), GCS (r=0.31, p<0.05), WMSI (r=-0.41, p<0.001) and PSSI (r=-0.34, p=0.04), which were got at the second visit. Patients, who were able to perform completely the submaximal ETT had at the first visit higher value of GLS (-12.8±0.5 vs -9.3±0.8%, p=0.001), LVEF (56.3±1.3 vs 49.5±2.4%, p=0.005), GRS (29.1±1.6 vs 22.0±3.3%, p=0.04), but lower value of WMSI (1.29±0.05 vs 1.60±0.08, p=0.001), PSSI (5.8±1.1 vs 12.2±2.2, p=0.005) and SDI (9.5±1.3 vs 15.3±2.3, p=0.027) compared to group of patients which were not able to perform completely the submaximal ETT. In the univariate analysis the odds ratio (OR) to performed completely submaximal ETT increased with higher GLS (OR 1.96, p=0.01), LVEF (OR 1.22, p=0.034) and lower WMSI (OR 0.04, p=0.03). By multivariable analysis, the value of GLS at early time after STEMI was the most powerful independent predictor of good exercise tolerance (OR 1.86, p=0.015). In particular, the cut-off value of GLS -12% predicted achieving the endpoint criteria of submaximal ETT with sensitivity and a specificity respectively of 88% and 67%.