Table 5.

Comparison of the Standard Deviations of all NN Intervals between Patients from 1a and 1b Subgroups with and without VNS‐Induced Heart Rate Decrease (Mann‐Whitney U test)

SDNN (ms)
	HR Decreased	HR Did not Decrease
Subgroup 1a	101.230 ± 30.284 (n = 26)	134.667 ± 8.687* (n = 6)
Subgroup 1b	63.666 ± 23.534# (n = 8)	104.5 ± 24.826*# (n = 4)

SDNN = standard deviation of all NN intervals; HR = heart rate.

*Statistically significant differences for comparisons between patients whose heart rate decreased and did not decrease within each subgroup (P < 0.05). #Statistically significant differences for intergroup comparisons (P < 0.05).