LAUSR

Citro et al.1 performed a commendable morbidity and mortality analysis in patients with Takotsubo cardiomyopathy (TC) with severely reduced left ventricular ejection fraction (LVEF ≤ 35%) from the Takotsubo Italian Network. Compared to patients with LVEF > 35%, patients with LVEF ≤ 35% were older, experienced cardiogenic shock and acute heart failure more frequently, and required more frequent intra-aortic balloon pump support acutely. Also at the longterm follow-up, higher rates of composite major adverse cardiac events (MACE) and rehospitalization rates for cardiac causes were observed in patients with reduced left ventricular function. These data are an eye-opener for clinicians and emphasize watchfulness for the higher future adverse event rates in patients with TC, especially those presenting with severely reduced LVEF. They also highlight the fact that TC may not be a benign reversible phenomenon (as once previously thought) due to higher recurrence of adverse events, diastolic dysfunction and associated mortality rates. In addition to the comparison of mortality based upon LVEF alone, it would be of great value to analyse the mortality data between the patients of primary vs. secondary forms of TC. Primary TC occurs in the setting of either psychic or emotional stimuli or without clear identifiable triggers (idiopathic), whereas secondary TC is triggered by physical stressors such as intracranial haemorrhage or cerebrovascular accident, trauma, sepsis, surgery, or other critical illnesses.2–5 It is now well known that secondary forms of TC are usually associated with much worse shortand long-term prognoses.2–4 We have also previously emphasized that primary TC, in comparison to secondary TC, generally has a relatively benign spectrum and a good overall prognosis, unless complicated by cardiogenic shock.3 Analysis of the previous .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. . registries such as RETAKO (Spanish National REgistry for TAKOtsubo cardiomyopathy) have demonstrated a significantly higher rate of morbidity and mortality in patients with secondary TC compared to primary forms, who otherwise had comparable demographic, functional and cardiovascular risk profiles.2 Similarly, secondary form TC patients had higher rates of cardiogenic shock, peak cardiac enzymes, increased use of inotropes, mechanical ventilator requirement, increased future recurrence and also higher readmission rates due to cardiovascular events.2,3 Even in the current study by Citro et al., Table 1 describes a higher rate of secondary/physical TC compared to primary/emotional TC in patients with LVEF < 35%, however a direct mortality and MACE comparison between primary and secondary forms of TC in patients with LVEF ≤ 35% is lacking. If the authors can share these data, it would be of great value to the readers and future researchers on this subject. It would be particularly important to know if there is a significant difference in the prognostic spectrum of patients with primary and secondary TC, despite a severely reduced LVEF on presentation. Recent registry data from the Mayo Clinic also demonstrated that the primary drivers for a high mortality rate in TC patients are the underlying precipitating physical triggers (secondary forms of TC) and non-cardiac co-morbidities such as cancer.5 Regardless, the authors point out a very important key finding that TC patients presenting with severe initial systolic dysfunction carry a much higher rate of future adverse events. Despite the apparent initial myocardial functional recovery, these patients deserve a closer clinical monitoring and appropriate preventive therapies to improve their future outcome. If the investigators could subanalyse the prognostic data based on the aetiology of TC (primary vs. secondary forms), it would be significantly valuable for the cardiology community and provide an additional understanding of the key players and clinical factors driving the morbidity and mortality.