Typical tako-tsubo cardiomyopathy (TTC) mimics acute anterior myocardial infarction (AMI) and the differential diagnosis is challenging before coronary angiography (CA) is performed: it demonstrates reduced or absent antegrade flow in the left anterior descending artery (LAD) in AMI whereas there is no such flow limiting in TTC. At the acute phase, we tested the usefulness of non-invasive coronary flow velocity (CFV) visualization by transthoracic Doppler echocardiography (TDE) to distinguish between these two diseases. For this purpose, we prospectively enrolled 28 consecutive patients (pts) with TTC (75 ± 10 years, 93% females), which were compared to 28 consecutive pts with AMI treated successfully by primary angioplasty (66 ± 12 years, 79% females). All pts underwent assessment of CFV in the distal part of the LAD just before CA, using color and pulsed wave TDE. In addition, the symmetric involvement of wall motion abnormalities (WMA) based on the extent of the disease far beyond one coronary territory in TTC was searched by TDE.

Results .– The distal LAD CVF was visible in 38/56 cases (68%) in the whole population, in all cases with TTC (100%) and in 10 cases with AMI (36%). The sensitivity (Se) and specificity (Sp) of the LAD CFV visualization for the diagnosis of TTC were 100% and 64% respectively with a diagnostic accuracy of 82%. By comparison, the pattern of WMA yielded a Se of 75%, Sp of 86%, and a diagnostic accuracy of 80%, this pattern being inconclusive in 11 cases. When CFV and pattern of WMA were combined together the Se and Sp were 75% and 96% respectively, with a diagnostic accuracy of 86% to detect TTC. The assessment of right ventricular WMA and left ventricular obstruction did not improve the diagnostic value of the combination of the above tools.

Conclusion .– Non-invasive evaluation of CFV in the distal LAD could be helpful to differentiate TTC from AMI, and its combination with the pattern of WMA improved slightly its diagnostic accuracy.