Atrial Cardiopathy and Sympatho-Vagal Imbalance in Cryptogenic Stroke: Pathogenic Mechanisms and Effects on Electrocardiographic Markers

Abstract

Recently, atrial cardiopathy has emerged as possible pathogenic mechanism in cryptogenic stroke and many electrocardiographic (ECG) markers have been proposed in order to detect an altered atrial substrate at an early stage. The autonomic nervous system (ANS) plays a well-known role in determining significant and heterogeneous electrophysiological changes of atrial cardiomyocytes, that promote atrial fibrillation episodes in cardioembolic stroke. Conversely, the role of ANS in atrial cardiopathy and cryptogenic stroke is less known, as well as ANS effects on ECG markers of atrial dysfunction. In this paper, we review the evidence linking ANS dysfunction and atrial cardiopathy as a possible pathogenic factor in cryptogenic stroke.

Keywords: ECG; P wave; P wave dispersion; atrial cardiopathy; atrial dilation; atrial fibrosis; autonomic nervous system; ischemic stroke.

Figure 1

Pathogenic mechanisms determining atrial cardiopathy and favoring an atrial prothrombotic state that can lead to ischemic stroke. ECM, extracellular matrix; ANS, autonomic nervous system.

Figure 2

Possible ANS-related mechanisms promoting atrial cardiopathy and cryptogenic stroke. TNFα, tumor necrosis factor alpha; IL-1β, Interleukin 1 Beta; IL-6, Interleukin 6; RAA, renin-angiotensin-aldosterone; ROS, reactive oxygen species; MMPs, matrix metalloproteinases; ECM, extracellular matrix.