Skip to main content

Table 1 Comparison of clinical and electrophysiological phenotype of heterozygous KCNQ1 variant carriers

From: Clinical and functional characterisation of a recurrent KCNQ1 variant in the Belgian population

 

c.1124_1127delTTCA/p.(Ile375Argfs*43)

c.332A > G/p.(Tyr111Cys) [11]

c.1022C > T/p.(Ala341Val) [8]

c.1522C > T/p.(Arg518*) [12]

LQTS1/Non-p.(Ile375Argfs*43)

LQTS1/Non-(p.Ala341Val)

Female gender

22/41 (54%)

44/80 (55%)

132/244 (54%)

54/86 (63%)

15/19 (79%)

122/205 (60%)

Median FU, year (IQR)

45 (17–57)

23 (11–43)

30 (15–51)

NA

27 (11–43)

32 (14–46)

Mean age at last FU ± S.E.M. (y)

41 ± 22

28 ± 20

NA

29 ± 23

27 ± 18

NA

SCD

1/41 (2%)

1/80 (1%)

NA

1/86 (1%)

1/19 (5%)

NA

SCD < 40 y

1/41 (2%)

1/80 (1%)

74/244 (30%)***

NA

1/19 (5%)

14/205 (7%)

Symptomatic

3/41 (7%)

27/80 (34%)**

NA

15/86 (17%)

6/19 (32%)**

NA

Symptomatic < 40 y

2/41 (5%)

24/80 (30%)***

184/244 (75%)***

NA

6/19 (32%)**

49/205 (24%)**

QTc ≥ 500 ms

6/40 (15%)

19/78 (24%)

45/153 (29%)

20/81 (25%)

7/19 (37%)

26/190 (14%)

QTc ≤ 440 ms

13/40 (33%)

8/78 (10%)**

16/153 (10%)**

13/81 (16%)

3/19 (16%)

45/190 (24%)

  1. Highest QTc measurements of resting ECGs were considered for the p.(Ile375Argfs*43) and LQTS1/Non p.(Ile375Argfs*43) populations. Statistical significance: **p < 0.01, ***p < 0.001, no p-value: not significant based on Fisher’s exact test
  2. FU, follow up; IQR, interquartile range; NA, not available; S.E.M., standard error of mean