Table 2

Longitudinal cTnI levels and per cent ejection fraction in asymptomatic subjects with DMD over a 3-year follow-up period demonstrating variable changes in troponin levels and systolic function over time

Subject	Age (years)	Test	Baseline	1 year	2 years	3 years
1	8	cTnI	0.02	0.02	–	–
1	8	%EF	63	60	–	–
2	8	cTnI	0.02	0.02	0.02	–
2	8	%EF	66	56	67	–
3	10	cTnI	0.22	0.06	–	–
3	10	%EF	63	56	–	–
4	12	cTnI	0.06	0.02	0.02	–
4	12	%EF	57	52	54	–
5	12	cTnI	0.05	0.64	–	–
5	12	%EF	60	50	–	–
6	12	cTnI	0.32	–	–	0.21
6	12	%EF	60	–	–	40
7	12	cTnI	0.02	–	–	0.02
7	12	%EF	66	–	–	54
8	14	cTnI	0.05	–	0.01	–
8	14	%EF	54	–	53	–
9	14	cTnI	0.01	–	0.02	0.02
9	14	%EF	41	–	32	36
10	15	cTnI	0.02	0.02	0.02	–
10	15	%EF	67	55	61	–
11	17	cTnI	0.02	0.06	–	–
11	17	%EF	51	43	–	–
12	17	cTnI	0.37	–	0.31	0.40
12	17	%EF	52	–	60	51
13	19	cTnI	0.28	0.14	0.05	0.02
13	19	%EF	54	49	48	41
14	21	cTnI	0.02	0.02	0.02	–
14	21	%EF	52	52	49	–
15	27	cTnI	0.03	0.03	–	–
15	27	%EF	61	56	–	–

cTnI, cardiac troponin I (ng/mL); DMD, Duchenne muscular dystrophy; %EF, per cent ejection fraction.