Abstract 6118: Velocity Vector Imaging Distinguishes Stress Cardiomyopathy from Acute ST-Elevation Anterior Myocardial Infarction
Background: Stress cardiomyopathy (SCM) is an acute and reversible cardiomyopathy that cannot be promptly distinguished from anterior myocardial infarction (AMI) without coronary angiography. We hypothesized that a detailed analysis of LV endocardial motion using a novel echocardiographic technique, velocity vector imaging (VVI), might distinguish SCM from AMI.
Methods and results: We analyzed echocardiographic images in 40 women with SCM and 40 women with AMI. In every SCM patient endocardial velocities demonstrated a single diastolic component, while each AMI patient had two diastolic components (Figure⇓). Significant differences in VVI indices for SCM vs. AMI were identified: maximal systolic velocity (Vmax-sys) (3.2 ± 0.24 vs. 4.1 ± 0.22 cm/s; p = 0.007); time to peak early diastolic velocity (TTP-dias) (503 ± 11.6 vs. 449 ± 8.2 ms; p = 0.0003); time to peak systolic velocity (TTP-sys) normalized (time interval divided by cycle length) to heart rate (N-TTP-sys) (0.23 ± 0.0092 vs. 0.18 ± 0.0065; p < 0.0001) and normalized TTP-dias (N-TTP-dias) (0.75 ± 0.0099 vs. 0.57 ± 0.0055; p < 0.0001). Each patient with SCM had longer N-TTP-dias (N- TTP-dias > 0.630) than each patient with AMI; the two groups had no overlap. The difference in N-TTP-dias was not related to differences in mitral inflow or HR (comparing SCM vs. AMI according to N-TTP-dias and adjusting for HR used multiple linear regression analysis).
Conclusions: Significant differences in endocardial velocity were observed in SCM and AMI. N-TTP-dias > 0.630 and a single diastolic component distinguish SCM from AMI with no overlap between groups. If prospectively validated, VVI may be useful in distinguishing SCM from AMI.