"Catecholamine-Mediated Myocarditis" Versus "Takotsubo Syndrome": What's in a Name? The Lumpers and Splitters Divide.

  • John E. Madias
  • Published 2016 in Journal of the American College of Cardiology

Abstract

I enjoyed reading the paper by Ferreira et al. (1) and the Editorial by Morley-Smith and Lyon (2) published in the Journal on catecholamine-mediated myocarditis (CMM), engendered by pheochromocytoma, and the evaluation of disease sequelae (scar and fibrosis) in their patients using cardiac magnetic resonance imaging. Although the Mayo Clinic diagnostic criteria of Takotsubo syndrome (TTS) (3) require the exclusion of pheochromocytoma to make the diagnosis, the bulk of the published reports on TTS has not abided by this exclusion (4,5). Accordingly, the 60 patients with CMM reported by Ferriera et al. (1) can be construed as those with lingering sequelae of pheochromocytoma-triggered TTS (the published reports portray the catecholamine-induced known as TTS as being some form of chemical, (toxic), cardiomyopathy). Also, if one considers the possibility of atypical or milder variants of TTS (4), it should be no surprise that some patients with CMM may present to the hospital without the dramatic phenotypes usually associated with TTS. Published case reports of TTS describe patients with long time delays in full recovery of heart function, persistence of electrocardiographic T-wave inversions and QTc prolongation, evidence of lingering autonomic sympathetic myocardial denervation, and even the presence of scarring or fibrosis. Accordingly, it is expected that CMM patients will have impaired systolic and diastolic strain imaging by myocardial tagging (a sensitive modality used by Ferreira et al. [1]) even after restoration of left ventricular ejection fraction (a cruder metric), with improvement of all the laboratory findings in the subgroup of patients who underwent repeat tests. It is conceivable that patients with TTS, with and without antecedent pheochromocytoma, differ in the time interval required for full restoration of heart function (systolic and diastolic), particularly with the use of sensitive modalities, and improvement of scarring and fibrosis. These issues need to be addressed in the future. The study by Ferreira et al. (1) from the 3 participating institutions could provide valuable insight by informing us about the acute clinical presentation of these 60 patients with CMM (new and surgically “cured”) in terms of clinical symptoms, signs, early echocardiographic findings, troponins, catecholamine types, and blood levels.

DOI: 10.1016/j.jacc.2016.06.059

Cite this paper

@article{Madias2016CatecholamineMediatedMV, title={"Catecholamine-Mediated Myocarditis" Versus "Takotsubo Syndrome": What's in a Name? The Lumpers and Splitters Divide.}, author={John E. Madias}, journal={Journal of the American College of Cardiology}, year={2016}, volume={68 13}, pages={1494} }