Heart and soul: heart rate variability and major depressionKidwell, Meyrick; Ellenbroek, Bart, A.Behavioural Pharmacology: April 2018 - Volume 29 - Issue 2 and 3 - Special Issue - p 152–164 doi: 10.1097/FBP.0000000000000387 REVIEW ARTICLES Buy Abstract Author InformationAuthors Article MetricsMetrics There is a bidirectional relationship between affective disorders and cardiovascular abnormalities, often described as a downward spiral, whereas major depressive disorders (MDD, and anxiety disorders) significantly increase the risk of developing cardiovascular diseases (CVD); CVD are also associated with increased risk of developing MDD (and anxiety disorders). Moreover, the prognosis and progression of CVD is significantly worsened in the presence of MDD. Heart rate variability (HRV) has often been suggested as a potential mediator in this comorbidity. In this review, we discuss HRV alterations in MDD. However, we mainly focus on the direct relationship between HRV alterations and psychiatric symptoms, rather than its relationship with CVD, as this has been reviewed elsewhere. After a general introduction to HRV and how it can be measured, we review how HRV is altered in MDD. We subsequently describe how antidepressant drugs affect HRV, showing that some classes (such as tricyclics) generally worsen HRV, whereas others (most notably selective serotonin reuptake inhibitors) have a more positive influence. We also review the effects of several other treatments, with a special focus on vagal nerve stimulation, finishing with some further considerations and recommendation for further research, both in humans and animals. Victoria University of Wellington, Behavioural Neurogenetics Group, Wellington, New Zealand Correspondence to Bart A. Ellenbroek, PhD, Victoria University of Wellington, Behavioural Neurogenetics Group, PO Box 600, Wellington 6104, New Zealand E-mail: email@example.com Received November 15, 2017 Accepted January 19, 2018 Copyright © 2018 YEAR Wolters Kluwer Health, Inc. All rights reserved.