Mind and body interventions in cardiology : The importance of the brain-heart connection

Mind and body interventions aim to harness the "relaxation response", reduce stress, and improve quality of life, which is important in the search for more holistic treatment approaches in cardiovascular medicine. This article describes the pertinent pathophysiological correlates building the mechanistic backbone for these interventions. They can be found in the complex connections of brain and heart (central and autonomic nervous system, hypothalamic-pituitary-adrenal axis), which play an important role in the development of various cardiovascular disease conditions and hold potential as therapeutic targets. The evidence regarding the effect of mind and body interventions in cardiology with a focus on arrhythmia and psychocardiology is reviewed systematically. To date, mostly small pilot studies prone to substantial bias and without adequate power have dominated the field and longer-term outcome data are lacking. Ultimately, integration of mind and body interventions could empower patients by strengthening their individual responsibility and mental power in addition to the benefits of stress reduction and improvement of quality of life. Whether this will translate into relevant longer-term clinical outcomes remains uncertain. Therefore, this field offers multifaceted opportunities for further research and practical applications.

The role of central autonomic nervous system dysfunction in Takotsubo syndrome: a systematic review

Introduction

Takotsubo syndrome (TTS), also known as stress cardiomyopathy or “broken heart” syndrome, is a mysterious condition that often mimics an acute myocardial infarction. Both are characterized by left ventricular systolic dysfunction. However, this dysfunction is reversible in the majority of TTS patients.

Purpose

Recent studies surprisingly demonstrated that TTS, initially perceived as a benign condition, has a long-term prognosis akin to myocardial infarction. Therefore, the health consequences and societal impact of TTS are not trivial. The pathophysiological mechanisms of TTS are not yet completely understood. In the last decade, attention has been increasingly focused on the putative role of the central nervous system in the pathogenesis of TTS.

Conclusion

In this review, we aim to summarize the state of the art in the field of the brain–heart axis, regional structural and functional brain abnormalities, and connectivity aberrancies in TTS.

Reversible increase in stress-associated neurobiological activity in the acute phase of Takotsubo syndrome; a brain 18F-FDG-PET study

INTRODUCTION

Takotsubo syndrome (TTS) is triggered mostly by physical and/or emotional stress that is processed in stress-associated brain regions, including the amygdala. However, it remains unclear whether such stress-induced brain activity is associated with TTS onset.

METHODS AND RESULTS

We acquired brain [¹⁸F]-2-fluoro-deoxy-d-glucose (¹⁸F-FDG) positron emission tomography in 4 TTS patients (44-82 yrs., 3 women) on days 2-4 (acute phase) and days 29-40 (recovery phase) after diagnosis of TTS was made by coronary angiography and left ventriculogram. The ¹⁸F-FDG uptake was measured globally and also in the pre-defined regions of interest of the bilateral amygdala on the common Montreal Neurological Institute space; all ¹⁸F-FDG images were normalized using automated image pre-processing. Amygdalar activity was calculated by dividing the ¹⁸F-FDG uptake of the amygdala by the global brain uptake. Left ventriculograms showed that apical ballooning was typical at diagnosis and was then relieved in the recovery phase. Amygdalar activity in the acute phase (0.872 ± 0.032) was higher than in the recovery phase (0.805 ± 0.037) (P = 0.013).

CONCLUSIONS

We report here 4 cases of TTS showing higher amygdalar activity in the acute phase as compared with the recovery phase, suggesting that increased stress-induced neurobiological activity is associated with TTS onset.

Functional neuroimaging in the acute phase of Takotsubo syndrome: volumetric and functional changes of the right insular cortex

Background

A brain–heart interaction has been proposed in Takotsubo syndrome (TTS). Structural changes in the limbic system and hypoconnectivity between certain brain areas in the chronic phase of the disease have been reported, but little is known concerning functional neuroimaging in the acute phase. We hypothesized anatomical and functional changes in the central nervous system and investigated whole-brain volumetric and functional connectivity alterations in the acute phase TTS patients compared to controls.

Methods

Anatomical and resting-state functional magnetic resonance imaging were performed in postmenopausal females: thirteen in the acute TTS phase and thirteen healthy controls without evidence of coronary artery disease. Voxel-based morphometry and graph theoretical analysis were applied to identify anatomical and functional differences between patients and controls.

Results

Significantly lower gray matter volumes were found in TTS patients in the right middle frontal gyrus (p = 0.004) and right subcallosal cortex (p = 0.009) compared to healthy controls. When lower threshold was applied, volumetric changes were noted in the right insular cortex (p = 0.0113), the right paracingulate cortex (p = 0.012), left amygdala (p = 0.018), left central opercular cortex (p = 0.017), right (p = 0.013) and left thalamus (p = 0.017), and left cerebral cortex (p = 0.017). Graph analysis revealed significantly (p < 0.01) lower functional connectivity in TTS patients compared to healthy controls, particularly in the connections originating from the right insular cortex, temporal lobes, and precuneus.

Conclusion

In the acute phase of TTS volumetric changes in frontal regions and the central autonomic network (i.e. insula, anterior cingulate cortex, and amygdala) were noted. In particular, the right insula, associated with sympathetic autonomic tone, had both volumetric and functional changes.

Graphic abstract