Brain functional connectivity in takotsubo cardiomyopathy patients. A systematic review of magnetic resonance imaging studies

Background: Functional neuroimaging studies may aid to our understanding of the pathophysiology of the takotsubo cardiomyopathy. Objective: The aim of the study was to review the available evidence of brain functional connectivity in takotsubo cardiomyopathy patients. Methods: This was a systematic review. We searched MEDLINE, LILACS, Ovid (Cochrane), Scopus, and Science Direct for studies conducting functional magnetic resonance imaging (fMRI) in takotsubo patients. After reviewing title/abstract and full text, we selected relevant studies, extracted methodological characteristics, and their main findings, and assessed their risk of bias with the Newcastle-Ottawa scale. We present a narrative review. Results: We included five case–control studies from 600 registries. The risk of bias was low; comparability was the main issue. Resting-state fMRI findings suggest significant differences for the hippocampus, the Insula, the amygdala, and the para-hippocampal gyrus. Task fMRI findings suggest significant differences for the Insula, the superior occipital gyrus, and the amygdala. Studies were heterogeneous about the laterality and directionality of these differences. Conclusion: Brain connectivity alterations involving elements relevant for autonomic control like the Insula and the Amygdala provide evidence in favor of the role of functional networks in the neurocardiology of stress-related cardiomyopathies. However, it is not possible to determine if this role is causal or consequential.