Author + information
- S0735109716348409-bedfc29bfa677e08d87971091570d11bShreyas Gowdar, MD and
- S0735109716348409-147ca38a7beff8007934710f80019bd6Lovely Chhabra, MD∗ ()
- ↵∗Department of Cardiovascular Medicine, Heartland Regional Medical Center, 3333 W. Deyoung Street, Marion, Illinois 62959
The study by Tornvall et al. (1) published in a recent issue of the Journal showed an increased mortality risk associated with Takotsubo cardiomyopathy (TC). After multivariate adjustment for coronary artery disease risk factors and risk markers for TC, the mortality rates were comparable among patients with TC and acute coronary syndrome (ACS). However, one of the major limitations was that the study failed to subdivide the patients of TC into its primary and secondary forms. Primary TC occurs in the setting of emotional or psychic stimuli or no identifiable triggers (idiopathic), whereas secondary TC is triggered by physical stressors such as sepsis, intracranial hemorrhage or cerebrovascular accident, trauma, surgery, or other critical illnesses (2). Secondary TC is associated with much worse short- and long-term prognoses (2). Primary TC, in comparison, generally has a benign spectrum and a good overall prognosis, unless complicated by cardiogenic shock. In a large recent study that used the RETAKO National Registry (Spanish REgistry for TAKOtsubo cardiomyopathy), the patients were divided into primary and secondary TC cohorts, who had otherwise similar demographic, functional, and cardiovascular risk profiles (2). Those with secondary TC had significantly increased mortality rates (hazard ratio: 3.41; 95% confidence interval: 1.14 to 10.16; p = 0.02), recurrences, and a composite of all-cause death, recurrence, and readmission rates due to cardiovascular causes. There were also higher rates of cardiogenic shock, peak creatine kinase levels, and increased use of inotropes and mechanical ventilation in the secondary TC cohort. Thus, the general conclusion of the current study led by Tornvall et al. that patients with TC and ACS have a similar prognosis should be perceived with caution. This is because many patients with secondary TC have increased morbidity and mortality due an alternate primary insult and/or cause. If the investigators could provide a subanalysis based on the etiology of TC (primary vs. secondary), it would be significantly valuable and would serve as a validation or refutation of this concept. Treatment approaches may also need to be tailored based on the presentation, with secondary TC forms needing more intensive monitoring and management.
Another notable observation is the low prevalence of diabetes mellitus (DM) in patients with TC compared with the control subjects who had coronary artery disease (1% vs. 6%; p < 0.01 for type 1 DM and 5.5% vs. 13.8%; p < 0.01 for type 2 DM) (1). The low prevalence of DM in TC has been identified in many previous studies (2–5). It is thus plausible that DM may be protective against the development of TC, due to a blunted sympathetic response (autonomic neuropathy) and diminished catecholamine secretion, which results in the amelioration of deleterious neurocardiac effects (3–5). This study adds to the growing body of evidence that recognizes this association. Future prospective studies may be helpful to explore the pathophysiology and treatment approaches of primary and secondary forms of TC and the pathophysiological relationship between DM and TC.
Please note: Both authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- American College of Cardiology Foundation
- Tornvall P.,
- Collste O.,
- Ehrenborg E.,
- Jarnbert-Petterson H.
- Nunez-Gil I.J.,
- Almendro-Delia M.,
- Andres M.,
- et al.
- Chhabra L.
- Madias J.E.