Monday preference in onset of takotsubo cardiomyopathy.
Acute cardiovascular events show definite temporal patterns of occurrence. Takotsubo cardiomyopathy (TTC) has been recently shown to exhibit a seasonal (summer) and circadian (morning) temporal distribution. The aim of this study, based on the database of a multicenter Italian network, was to investigate the possible existence of a weekly pattern of onset of TTC. The study included all cases of TTC admitted to the coronary care unit of 8 referral cardiac centers in Italy (five in Southern Italy and three in Northern Italy, respectively), belonging to the Takotsubo Italian Network (January 2002-December 2008). Day of admission was categorized into seven 1-day intervals according by week, and chronobiological analysis was performed by partial Fourier series. The database included 112 patients with TTC (92.9% females). The weekly distribution identified the highest number of cases on Monday and the lowest on Saturday. Chronobiologic analysis yielded a rhythmic pattern with a significant peak on Monday (P = .036). This study confirms a Monday preference for TTC occurrence on Monday, similar to that reported for acute myocardial infarction. Stress of starting weekly day life activities, could play a triggering role.