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Aims: Left ventricular (LV) diastolic filling is characterized by the formation of a vortex that supports an efficient transit into systolic ejection. Aim of this study was to assess the intraventricular (IV) blood flow dynamics among patients with ST elevated myocardial infarction (STEMI) at different degrees of LV dysfunction, in the attempt to find novel indicators of LV pump efficiency., Methods and Results: Sixty-four subjects, 34 consecutive STEMI patients and 30 healthy controls, underwent before hospital discharge 2D speckle tracking echocardiography to assess global longitudinal strain (GLS), and echo-particle image velocimetry analysis to assess flow energetic parameters. Left ventricular volumes ejection fraction (LVEF) and global wall motion score index (GWMSI) were evaluated by 3D echocardiography. ST elevated myocardial infarction patients were subdivided into three groups according to LVEF. Energy dissipation, vorticity fluctuation, and kinetic energy fluctuation indexes, which characterize the degree of disturbance in the flow, exhibit a biphasic behaviour in STEMI patients when compared with controls, with the highest values in patients with still preserved LV function and progressive lower values with LV function worsening. Significant linear correlations were found between energy dissipation index and both LVEF and GLS (r = 0.57, P < 0.001 and r = -0.61, P = 0.001, respectively). Kinetic energy fluctuation index significantly correlates with both LVEF (r = 0.75, P < 0.001) and GLS (-0.58, P = 0.002). Finally, a significant correlation was observed between GWMSI and energy dissipation index (-0.56, P = 0.008)., Conclusions: The present study describes, for the first time, the progression of IV flow energetic properties in patients with acute myocardial infarction at different stages of LV dysfunction when compared with healthy controls. Further data are needed to assess the role of these parameters in the development and maintenance of LV dysfunction., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.)

Aims: Global and regional longitudinal strain (GLS-RLS) assessed by two-dimensional speckle tracking echocardiography (2D-STE) are considered reliable indexes of left-ventricular (LV) function and myocardial viability in chronic ischaemic patients when compared with delayed-enhanced cardiac magnetic resonance (DE-CMR). In the present study, we tested whether GLS and RLS could also identify early myocardial dysfunction and transmural extent of myocardial scar in patients with acute ST elevation myocardial infarction (STEMI) and relatively preserved LV function., Methods and Results: Twenty STEMI patients with LVEF ≥40%, treated with PPCI within 6 h from symptoms onset, underwent DE-CMR and 2D-echocardiography for 2D-STE analysis 6 ± 2 days after STEMI. Wall motion score index (WMSI) and LV ejection fraction (LVEF) were calculated by both methods. Infarct size and transmural extent of necrosis were assessed by CMR. GLS and RLS were obtained by 2D-STE. Mean GLS of the study population was -14 ± 3.3, showing a significant correlation with both LVEF and WMSI, by CMR (r = -0.86, P = 0.001, and r = 0.80, P = 0.001, respectively) and time-to-PCI (r = 0.66, P = 0.038). A weaker correlation was found between GLS and LVEF and WMSI assessed by 2D-echo (r = -0.65, P = 0.001, and r = 0.53, P = 0.013, respectively). RLS was significantly lower in DE-segments when compared with normal myocardium (P < 0.0001). A cut-off value of RLS of -12.3% by receiver-operating characteristic (ROC) curves identified DE-segments (sensitivity 82%, specificity 78%), whereas a cut-off value of -11.5% identified transmural extent of DE (sensitivity 75%, specificity 78%)., Conclusion: Our findings indicate that RLS and GLS evaluation provides an accurate assessment of global myocardial function and of the presence of segments with transmural extent of necrosis, with several potential clinical implications.

Aims: The aim of this study was to analyse the relationship between infarct-related artery residual stenosis, assessed by quantitative coronary angiography, and left ventricular function changes during the in-hospital period in patients with acute myocardial infarction undergoing thrombolytic treatment., Methods and Results: The study population consisted of 90 patients with acute myocardial infarction treated with thrombolysis within 6 h of the onset of symptoms. Left ventricular function was serially assessed by an echocardiographic asynergy score (before thrombolysis and pre-discharge). Left ventricular end-diastolic and end-systolic volumes were also calculated. Coronary stenosis was evaluated by computer-assisted videodensitometric analysis at pre-discharge coronary angiography. Three subgroups were identified on the basis of left ventricular function changes: 25 patients (Group A) with regional myocardial improvement (echo score from 7.5 +/- 3.5 to 4.3 +/- 3.2), 51 (Group B) with no variation in echo score (4.8 +/- 2.7) and 14 (Group C) with myocardial regional worsening (echo score from 4.4 +/- 2.1 to 8.8 +/- 2.4). Group A patients exhibited a very high incidence of infarct-related artery patency (23/25 patients, 92%) vs 71% with unchanged (Group B) and 14% (Group C) with worsening regional left ventricular function (P < 0.001). Subdivision of the study population on the basis of residual stenosis severity showed that a significant improvement in left ventricular function was present only in the subgroup with residual stenosis < 75% (echo score from 5.2 +/- 3.4 to 3.6 +/- 2.9, P < 0.001)., Conclusion: These results support the important role exerted by complete coronary patency after thrombolysis in inducing left ventricular function recovery, and the poor functional improvement in patients with incomplete coronary patency.