Incidence of takotsubo syndrome over a period of 12 years

Abstract Background Takotsubo syndrome (TTS), first described in Japan in 1990, mimics acute coronary syndrome (ACS). A rising incidence of TTS has been observed worldwide since 2005 and an increasing number of case reports and retrospective as well as prospective studies has been published over the past years, with a steep rise in the number of publications from 2006 onwards. This may be due to a definite increase of the TTS prevalence in the general population or a heightened awareness of this disease entity among physicians. Purpose The aim of this study was to assess the incidence of TTS in patients hospitalized for an ACS and to examine its trend over a period of more than 12 years. Methods Between May 2000 and December 2012, consecutive patients from one institution with diagnosis of TTS fulfilling the criteria of the Heart Failure Association had been prospectively included in a database. The incidence of TTS among patients with suspected ACS undergoing coronary angiography and among all hospital admissions was assessed and compared over time. Results During a period of 12.5 years, 95 patients with TTS were observed, 84 females (88%) and 11 males (12%) with a mean age 71±12 years. Two patients died in-hospital (30-day mortality 2.1%). During the observation period recurrence of TTS occurred in 6/95 patients (6.3%). The number of TTS events diagnosed annually ranged from 4 to 11 (mean 7.6/year). During the entire period, 4297 patients with suspected ACS underwent emergency cardiac catheterization demonstrating a TTS event in 101 patients (incidence overall 2.35%). Among 1405 females with ACS, there were 90 TTS events, resulting in an incidence of 6.4% in females. In males the incidence of TTS was 0.4% (11/2892 ACS). During the first year of the observation period (2000 – 2001), the incidence of TTS was 2.3% in all patients and 6.3% in females with ACS. During the last year (2011 – 2012), the incidence of TTS was 1.8% in the whole cohort and 4.3% in females. Comparing the initial and subsequent 6-year period, the incidence of TTS was not different (2.34% vs 2.35%, p=ns). Divided into four 3-year intervals, also no significant difference in the incidence of TTS was observed. Overall, TTS was diagnosed in 0.05% of all hospital admissions with virtually no difference during the first and subsequent 6-year period. Conclusion In this prospective study over more than 12 years, the proportion of patients with a diagnosis of TTS among patients with suspected ACS and among all hospital admissions was unchanged. The large increase in case reports and publications on TTS over the last years since 2006, therefore, reflects the heightened awareness of this disease entity.