To the Editor:
We wish to thank you very much for publishing the excellent letter from Dr Almendro-Delia and Dr Hidalgo-Urbano, reporting their experience with Tako-tsubo syndrome and its midventricular variant. The first cases of this disease were discovered in 19901 and, although at first it was considered to be highly infrequent, it is now thought to account for more than 1% of acute infarctions (5% in women).2 Years later, there are increasing reports of cases and of variants characterized by the fact that they do not involve the left ventricular apex at the time of diagnosis. As the authors point out in their letter, this tendency could be due to the widespread use of imaging techniques (echocardiography, catheterization) during the acute phase, but also to the wider spread recognition by physicians of a previously unknown condition, as reflected by the increase in the number of publications on the subject in recent years (Figure). In our series, studied between 2003 and 2007, 37% of the cases (23 of 62 patients) corresponded to atypical forms.3 Given that the prognosis appears to be benign, despite occasional serious complications,3 the greatest enigma lies in elucidating the pathophysiological mechanism. Both the neurohormonal imbalance associated with catecholaminergic influence and microvascular dysfunction measured by the thrombolysis in myocardial infarction (TIMI) frame counts (TFC) analyzed by Almendro-Delia and Hidalgo-Urbano, among other factors, have been pointed to by a number of authors as being implicated.2,3 However, the influence of an elongated, or recurrent, anterior descending artery4 should be clarified.
Figure. Publications included in PubMed, according to years, in which the terms "tako-tsubo" or "apical ballooning" appear.