title: Periodic Repolarisation Dynamics: A Natural Probe of the Ventricular Response to Sympathetic Activation.
abstract: Periodic repolarisation dynamics (PRD) refers to low-frequency (≤0.1Hz) modulations of cardiac repolarisation instability. Spontaneous PRD can be assessed non-invasively from 3D high-resolution resting ECGs. Physiological and experimental studies have indicated that PRD correlates with efferent sympathetic nerve activity, which clusters in low-frequency bursts. PRD is increased by physiological provocations that lead to an enhancement of sympathetic activity, whereas it is suppressed by pharmacological β-blockade. Electrophysiological studies revealed that PRD occurs independently from heart rate variability. Increased PRD under resting conditions is a strong predictor of mortality in post-myocardial infarction (post-MI) patients, yielding independent prognostic value from left-ventricular ejection fraction (LVEF), heart rate variability, the Global Registry of Acute Coronary Events score and other established risk markers. The predictive value of PRD is particularly strong in post-MI patients with preserved LVEF (>35 %) in whom it identifies a new high-risk group of patients. The upcoming Implantable Cardiac Monitors in High-Risk Post-Infarction Patients with Cardiac Autonomic Dysfunction and Moderately Reduced Left Ventricular Ejection Fraction (SMART-MI) trial will test prophylactic strategies in high-risk post-MI patients with LVEF 36-50 % identified by PRD and deceleration capacity of heart rate (NCT02594488).
authors.affiliation: Munich University Clinic, Munich, Germany; Deutsches Zentrum für Herzkreislaufforschung (DZHK), Munich, Germany.
authors.forename: Konstantinos D
authors.initials: KD
authors.lastname: Rizas
authors.affiliation: Munich University Clinic, Munich, Germany; Deutsches Zentrum für Herzkreislaufforschung (DZHK), Munich, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Hamm
authors.affiliation: Munich University Clinic, Munich, Germany; Deutsches Zentrum für Herzkreislaufforschung (DZHK), Munich, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Kääb
authors.affiliation: Deutsches Zentrum für Herzkreislaufforschung (DZHK), Munich, Germany; Technical University of Munich, Munich, Germany.
authors.forename: Georg
authors.initials: G
authors.lastname: Schmidt
authors.affiliation: Munich University Clinic, Munich, Germany; Deutsches Zentrum für Herzkreislaufforschung (DZHK), Munich, Germany.
authors.forename: Axel
authors.initials: A
authors.lastname: Bauer
keywords: myocardial infarction; periodic repolarisation dynamics; risk stratification; spatial dispersion of repolarisation; sudden death; sympathetic nervous system