Takotsubo cardiomyopathy: still much more to learn

Takotsubo cardiomyopathy (TTC) was first described in 1990 when Japanese cardiologists from the Hiroshima Asa General Hospital published their findings in a chapter of a Japanese medical text. At that time, TTC was completely unrecognised in Europe and North America, and for years the disorder was thought to affect only Asians. Then in 2003, the first study of TTC in Caucasians indicated that this was actually a widespread affliction.1 By 2013, the number of publications related to TTC had risen to 1879, a number mirroring increased awareness and interest in this disease. But while numerous case reports of TTC exist in the literature, large systematic registries or trials are lacking. The main characteristic of TTC is transient, reversible, systolic dysfunction of the left ventricle. Relatively little definitive information is available otherwise, and as a result many cases likely remain unreported and often misdiagnosed, frequently as acute coronary syndrome (ACS). In particular, TTC may remain unrecognised if symptomatic patients do not undergo corroborating coronary angiography. In this regard, it is likely that subclinical or mild cases of TTC exist, but remain unidentified due to limited diagnostic workup, particularly in centres without primary percutaneous coronary intervention facilities. Not surprisingly, the exact prevalence remains unknown. However, it is estimated that TTC affects approximately 2% of patients presenting as ACS. Rates of TTC in women with ACS are suggested to be higher at 5.9–7.5%.2 ,3 By searching for the International Classification of Diseases, ninth revision, code 429.83, among 33 506 402 hospitalisations in a nationwide inpatient sample database, Deshmukh et al 4 found that 6837 patients in the USA were diagnosed with TTC during 2008, accounting for 0.02% of all hospitalisations that year. Nevertheless, we do not know if cases in the nationwide inpatient sample database were misdiagnosed, wrongly classified, or unrecognised and …