Abstract 2214: Impact of Acute Myocardial Infarction and Reperfusion Therapy on Left Ventricular Twist
Background. LV twist, defined as the net difference between counterclockwise rotation of LV apex and clockwise rotation of LV base during systole, is an important determinant of LV systolic function.
Aim. To study the changes of LV twist after AMI and its relationship to global and regional LV systolic function, AMI site and efficacy of reperfusion therapy.
Methods. A total of 77 patients with a first ST-elevation AMI (58±11 years, 78% male) were included. All patients underwent primary PCI. 2D speckle tracking echocardiography was performed within 48 hours of PCI for the assessment of apical and basal rotation and LV twist. Immediately after, myocardial contrast echocardiography (MCE) with Perflutren was performed for the assessment of post-AMI reperfusion. MCE perfusion was scored (1=normal; 2=reduced; 3=absent) on a 16 segment LV model; myocardial perfusion was considered incomplete when absence of perfusion involved ≥25% of the LV.
Results. LV EF, apical and basal rotation and LV twist were significantly lower among AMI patients, as compared to controls (Table A⇓). LV EF, extent of wall motion abnormalities, infarct site (anterior vs. inferoposterior) and extent of absent perfusion were significantly related to LV twist (r=0.619, p=0.0001; r=0.640, p<0.0001; r=0.423, p<0.0001; r=0.435, p<0.0001, respectively). Apical rotation and LV twist among AMI patients with incomplete perfusion after primary PCI were significantly lower as compared to patients with complete perfusion (Table B⇓).
Conclusions. LV twist is significantly decreased after AMI and is significantly related to global and regional LV systolic function, AMI site and efficacy of reperfusion therapy. In particular, incomplete perfusion after PCI significantly widens the detrimental effects of AMI on LV twist and apical rotation.