+100%-

Bradycardia and Arrhythmias

Download as a PDF

Bradycardia is defined as a HR of less than 60 beats per minute (bpm). Lower basal HR is regarded as a consequence of reduced SNS activity in the initial stages following SCI (Teasell et al. 1996). Those with cervical or high thoracic injuries are at particular risk of bradycardia and other arrhythmias. These injuries lead to dysrhythmias due to intact parasympathetic control combined with impaired supraspinal sympathetic control which leads to unchecked parasympathetic tone (Biering-Sørensen et al., 2018). The first few weeks after SCI is the most common time point for bradycardia or arrhythmias to occur, and become less common as time goes on (Biering-Sørensen et al., 2018). A study by Hector and colleagues (2013) found that in the first two weeks after cervical SCI the incidence of bradycardia was 14 to 77%. When looking at HR less than 50 bpm, the authors found this changed to 26 to 64% of cervical SCI patients, and a frequency of 0 to 13% in thoracic or lumbar SCI (Hector et al., 2013). Lastly, the authors found that bradycardia peaked 4 to 6 days after the cervical SCI (Hector et al., 2013). Other arrhythmias post-SCI occurred in 18 to 27% of cervical injuries, and none in thoracic or lumbar SCIs (Hector et al., 2013). The authors recommend using 24 hour ECG recordings as opposed to 12 hour recordings because many arrhythmias may be missed (Hector et al., 2013).