Table 1 Baseline clinical demographics

Age at baseline CMR, years

63 ± 9

59 ± 14

Age at diagnosis, years

57 ± 11

53 ± 15

Sex (% Male)

26 (67%)

308 (75%)

Apical variant

4 (10%)

66 (16%)

Atrial fibrillation

3 (8%)

8 (2%)

New York Heart Association Class

I

20 (51%)

258 (63%)

II

19 (49%)

152 (37%)

III

0 (0%)

0 (0%)

LVOT obstruction > 30 mmHg

15 (41%)

148 (36%)

Family history of sudden death

7 (18%)

57 (14%)

Non sustained ventricular tachycardia

7 (18%)

45 (11%)

Syncope

9 (23%)

66 (16%)

Wall thickness ≥ 30 mm

4 (10%)

16 (4%)

CMR parameters (median, IQR)

Wall Thickness, mm

20 (6)

19 (6)

LVEDVI, ml/BSA

66 (22)

67 (19)

LVESVI, ml/BSA

18 (10)

16 (9)

LVEF, %

73 (16)

76 (10)

LGE (% of total myocardial mass)

23 (20)

10 (20)

LGE (≥ 5%)

34 (87%)

295 (67%)

LAVI ml/BSA

65 (38)

53 (25)

Inducible perfusion defect

32 (82%)

344 (84%)

Perfusion summed difference score

14.4 (6.9)

12.8 (8.2)

Mitral regurgitation

None

18 (46%)

254 (62%)

Mild

17 (44%)

127 (31%)

 > Mild

4 (10%)

29 (7%)

Medications

Beta blocker

25(64%)

250 (61%)

Calcium channel blocker

5 (13%)

70 (17%)

ACEi/ARB

3 (8%)

70 (17%)

Aspirin

11 (28%)

82 (20%)

Warfarin

7 (18%)

12 (3%)

Amiodarone

3 (8%)

4 (1%)

Co-morbidities

Coronary artery disease

3 (8%)

41 (10%)

Chronic obstructive pulmonary disease

0 (0%)

7 (2%)

Hypercholesterolemia

11 (28%)

61 (15%)

Diabetes

7 (18%)

32 (8%)

Hypertension

10 (26%)

97 (24%)

Stroke

1 (3%)

3 (1%)