Sinus Node Function
Figure 1A shows Holter observed heart rate metrics including minimum,
average and peak heart rate (in beats per minutes / bpm) as stratified
by AF GRS quartiles (n = L: 22; LI: 21; HI 23; H: 20). Baseline
demographics were similar between the four quartiles labeled: age (L: 51
± 8 years; LI: 52 ± 9 years; HI: 51 ± 9 years; H: 50 ± 9 years), male
gender percent (L: 50%; LI: 53%; HI 50%; H: 50%); Body mass index
(kg/m2) (L: 24.9 ± 4.4 ; LI: 24.1 ± 5.0; HI: 24.1 ± 4.6; H: 25.0 ± 6.1);
ejection fraction (L: 54 ± 6 %; LI: 53 ± 8; HI: 54 ± 7; H: 56 ± 7).
There is an observed association of increased minimum and average heart
rate with increased GRS (minimum L: 55 ± 5 bpm; LI: 56 ± 5 bpm; HI: 58
± 6 bpm; H: 62 ± 5 bpm; p = 0.02; average L: 75 ± 6 bpm; LI: 74 ± 7 bpm;
HI: 79 ± 8 bpm; H: 81 ± 8 bpm; p = 0.01). There is no association
between peak heart rate and GRS (maximum L: 125 ± 9 bpm; LI: 123 ± 9
bpm; HI: 128 ± 9 bpm; H: 125 ± 8 bpm; p = 0.30). Figure 1B shows Holter
observed heart rate variability metrics including SDNN and RMSDD as
stratified by GRS quartiles. There is an observed trend of decreased HR
variability with increased AF GRS (SDNN L: 121 ± 13 ms; LI: 120 ± 12 ms;
HI: 114 ± 13 ms; H: 108 ± 14 ms; p = 0.01; RMSDD L: 25 ± 4 ms; LI: 24
± 5 ms; HI: 22 ± 6 s; H: 21 ± 5 ms; p = 0.04).