Chronobiology of Tako‐Tsubo Cardiomyopathy (Apical Ballooning Syndrome)

To the Editor: We read the recent paper by Manfredini and colleagues1 with interest. The study explored the seasonal variation in the presentation patterns of 112 consecutive patients with Tako-tsubo cardiomyopathy (apical ballooning syndrome) from a multicenter Italian registry. Their data indicated that Tako-tsubo cardiomyopathy occurs predominantly in the summer months and that the seasonal variation is independent of age. This contrasts with excess events in the winter for acute myocardial infarction.2 Factors such as temperature and barometric pressure, which may modulate sympathetic activity, have been proposed as mechanisms for this relationship, although there are also studies that have not observed a seasonal variation in the frequency and mortality from myocardial infarction or infarct size.3, 4 One of the first case series of Tako-tsubo cardiomyopathy in the United States was described in 2004 from our institution,5 and data have been gathered on this unique cardiomyopathy since then.6 The data from Manfredini and colleagues are intriguing, and the seasonal presentation pattern of 186 consecutive patients at the Mayo Clinic was therefore analyzed. Contrary to their report, a chronobiological pattern was not found in the incidence of the cardiomyopathy (Figure 1). This was true whether there was an emotional, physical, or no trigger identified at the time of presentation and when patients younger and older than 65 were analyzed. Therefore, the findings by Manfredini and colleagues should be considered preliminary and hypothesis generating, and other investigators should evaluate their cohorts of Tako-tsubo cardiomyopathy to confirm whether there is a seasonal variation in the incidence. Apical ballooning syndrome (ABS) events according to month. Conflict of Interest: The editor in chief has reviewed the conflict of interest checklist provided by the authors and has determined that the authors have no financial or any other kind of personal conflicts with this paper. Author Contributions: All authors had equal roles in all aspects of this response. Sponsor's Role: None.