. 2009 Apr 14;14(2):108–118. doi: 10.1111/j.1542-474X.2009.00285.x

Table 2.

Differences between T‐Wave Alternans (TWA) Profiles of Healthy Subjects and Implantable Cardioverter‐Defibrillator (ICD) Patients as Depicted in the Measured Variables and Distinctive Features

Features	Healthy Subjects (N = 31)	ICD Patients (N = 33)
Age (years)	36 ± 9	50 ± 18
Age (years)	(18–55)	(15–73)^a
Max TWA at rest (μV)	1 ± 2	8 ± 9
Max TWA at rest (μV)	(0–5)	(0–38)^a
Max TWA during test (μV)	26 ± 13	37 ± 20
Max TWA during test (μV)	(4–61)	(7–101)^b
Heart rate (HR) at max	118 ± 8	90 ± 17
TWA during test (bpm)	(92–127)	(61–126)^a
HR at rest (bpm)	79 ± 10	67 ± 15
HR at rest (bpm)	(62–98)	(47–99)^a

All variables displayed in mean ± SD (minimum – maximum).

^aP < 0.001 compared to healthy subjects (Mann‐Whitney test).

^bP = 0.009 compared to healthy subjects (Mann‐Whitney test).