Prof. Arno Villringer | Heart-brain Interactions, Brain Function and Cognition during Cardiac Arrhythmias

Cardiac arrhythmias such as the occurrence of extrasystoles (premature atrial/ventricular contractions (PAC/PVC)) and especially absolute arrhythmias due to atrial fibrillation (AF) are extremely common and affect most people during their lifetime. AF in particular is of great clinical importance as it often leads to heart failure, stroke and dementia.

Since our previous studies have shown that any regular heartbeat modulates brain function and cognition via the heart-brain interaction (HBI), we (i) infer that this is also the case for abnormal heartbeats associated with abnormal HBI, and specifically (ii) hypothesize that overall brain function and cognitive performance are negatively affected by arrhythmic heartbeats potentially associated with processing of a mismatch/prediction error signal. Finally, we hypothesize (iii) that normalization of atrial fibrillation may restore brain function/cognition - at least partially.

Two groups of patients, 50 patients with atrial fibrillation (study 1) and 50 patients with frequent PAC/PVC (extrasystoles) (study 2) will be studied in comparison to control groups matched for age, gender and risk factors. The study is exploratory in nature as it is the first of its kind. After 20 patients in each group, an interim analysis will be conducted to estimate effect sizes and possibly adjust the required number of patients, also with a view to identifying possible gender differences.

In addition to the cross-section assessment, longitudinal study 1 will also examine the effect of restoring (normal) sinus rhythm by pulmonary vein isolation (PVI) up to six months later. Cognition will be assessed with a neuropsychological test battery and brain function with electroencephalography (EEG) and functional and structural magnetic resonance imaging (MRI). The HBI is measured by EEG-based heartbeat evoked potentials (HEP) and by the heart-brain information transfer assessed by simultaneous EEG/ECG. In addition, blood and urine samples are taken from the patients at Leipzig University Hospital in order to be able to analyze relevant biomarkers of cardiac and neurological damage.

The results of this study are potentially of great importance for our assessment of the mental capacity of patients with cardiac arrhythmias and should therefore have important implications for their treatment and rehabilitation.