Electrocardiogram-based predictors for arrhythmia after spinal cord injury

Abstract

The higher T(peak)-T(end) variability, QTVI and P-wave variability in individuals with SCI could be markers of severity of injury to cardiac autonomic (sympathetic) pathways after SCI, and may represent new risk assessment parameters for predisposition to cardiac arrhythmias in this population.

Cardiovascular Function in Individuals with Incomplete Spinal Cord Injury: A Systematic Review

“…23,28 Sahota et al 23 reported that individuals with an autonomically incomplete SCI (established via catecholamines and BP variability) exhibited a higher SBP and HR at rest and in response to HUT. Ravensbergen et al 28 reported that variability in the electrocardiogram (defined using the QT variability index and the transmural dispersion of repolarization), which may provide an indication of the risk of developing lethal ventricular arrhythmias, was improved in individuals with autonomically incomplete SCI (established via sympathetic skin response [SSR], catecholamines, and low-frequency power of SBP) compared to persons with autonomically complete SCI. It is important to note that neither of the 2 studies that investigated autonomic completeness of injury further stratified their sample by lesion level; thus, the reported differences between autonomically complete and incomplete SCI may also be due to a between-group difference in lesion level.…”

<b>Profile of the cardiac repolarization in cervical spinal cord injury subjects performing physical exercise

“…It results in increased morbidity and mortality, but the instability is directly related to the type and degree of the injury, maintaining parasympathetic input to the heart intact while the spinal sympathetic system loses supraspinal autonomic control. The interruption of cardiac sympathetic innervation and parasympathetic control intact promotes bradycardia, reduces myocardial contractility and cardiac arrest occur due to a vago-vagal reflex, that contribute for autonomic dysfunction can lead to ventricular arrhythmias (Lehmann, Shandling, Yusi, & Froelicher, 1989;Ravensbergen, Walsh, Krassioukov, & Claydon, 2012).…”

“…Electrocardiographic ventricular repolarization (QT interval) parameters have been used as predictors of increased risk of ventricular arrhythmias and sudden death in patients with SCI (Akbal et al, 2014;La Fountaine et al, 2010;Ravensbergen et al, 2012). Acute phase of the cervical SCI and consequently increases in QT interval can be due to sympathetic nerves damage after separation from supraspinal control associated to parasympathetic nerves intact that negatively change cardiac autonomic control (La Fountaine et al, 2010).…”

Autonomic Response in Subjects with Spinal Cord Injury: Brief Comments

“…14,15 Impairment of the autonomic cardiac regulation has been associated to increased incidence of cardiac arrhythmias and the analysis of heart rate variability (HRV) has been used as a tool for noninvasive assessment of cardiac autonomic balance in physiological and pathological conditions. 16,17,18 HRV analysis may provide a noninvasive method for estimating the sympatho-vagal balance.…”

“…15,25,26 Acute phase of the cervical SCI and consequently increases in QT interval can be due to sympathetic nerves damage after separation from supraspinal control associated to parasympathetic nerves intact that negatively change cardiac autonomic control. 26 On the other hand, La Fountaine and colleagues 26 found longer QTc intervals in paraplegia when compared to tetraplegia and Chung et al…”