Blood norepinephrine/epinephrine/dopamine measurements in 108 patients with takotsubo syndrome from the world literature: pathophysiological implications

Objectives Release of norepinephrine (NE) from neuronal cardiac nerve endings and/or blood-borne catecholamines (CATs), mainly epinephrine (EPI), may mediate TTS. The aim of this study was to document the levels of NE, EPI, and dopamine (DA) in patients with TTS. Materials and methods A qualitative/quantitative meta-analysis of CATs and their relationship to age, gender, and triggers, was carried out, employing the world literature on TTS, published in PubMed. Results NE/EPI/DA in108 patients with TTS, 65.2 +/- 16.4 years old, 89 (82.4%) women, revealed that: NE was measured more frequently than EPI, and EPI than DA; the timing of the measurements was variable; CATs were reported variably (qualitatively/quantitatively/with/without upper limits of normal); NE/EPI or NE/EPI/DA rose to the same degree; CATs were normal, or mildly/moderately elevated, with only 6 patients showing markedly elevated NE/EP/DA; NE, EPI, and DA were similar in patients with physical triggers and NE was similar in patients with physical, emotional, or no triggers (p = 0.47); EPI was higher than NE in patients with emotional triggers and EPI was higher in patients with emotional than physical triggers (p = 0.012); NE, EPI, and DA rose to the same proportion in men and women; types of TTS triggers were distributed proportionally in men and women. Conclusion NE, EPI, and DA rise proportionally in patients with TTS; CATs are mildly/moderately, and rarely markedly elevated; measurements of CATs should become more systematised; although CATs may not be essential for TTS diagnosis, they may contribute to prognosis and elucidation of the pathophysiology of TTS.

Automated summary

The levels of NE, EPI, and DA rise proportionally in patients with TTS; CATs are usually mildly/moderately elevated, with only a few showing markedly high levels; there should be a more systematic approach to measuring CATs; although not essential for TTS diagnosis, CATs may play a role in prognosis and understanding the pathophysiology of TTS.