Clinical features of subjects with β MHC mutations classified according to genotype and affected domain of β MHC
| Mutation* | Number affected | Age at diagnosis (years) | Age at death† (years) | Deaths age⩽60/deaths age⩽40 | Myectomy or NSRT | ECG Estes score | MLVWT (mm) | Echo LVH score | LVEDD (mm) | LA (mm) |
|---|---|---|---|---|---|---|---|---|---|---|
| *Missense mutations categorised according to affected functional domain: (0), no change in overall charge of substituted amino acid at affected site; (+), change in overall charge of substituted amino acid at affected site. | ||||||||||
| †Death includes death, aborted cardiac death (resuscitated cardiac arrest or appropriate implantable cardioverter defibrillator shock), and cardiac transplantation. | ||||||||||
| Data for diagnosis, age at death, ECG Estes score, MLVWT, echo LVH score, LVEDD, and LA expressed as mean (SD). | ||||||||||
| Echo, echocardiographic; LA, left atrial diameter; LVEDD, left ventricular end diastolic diameter; MLVWT, maximum left ventricular wall thickness; NA, not applicable; NSRT, non-surgical septal reduction therapy. | ||||||||||
| Active site (0) | ||||||||||
| Ala196Thr | 3 | 42 (4) | 54 | 1/0 | 0 | 5 (3) | 27 (4) | 7 (4) | 51 (6) | 54 (4) |
| Pro211Leu | 3 | 33 (13) | NA | 0/0 | 0 | 2 (4) | 13 (10) | 1 (1) | 41 (4) | 35 (7) |
| Active site (+) | ||||||||||
| Arg249Gln | 3 | 54 (20) | 77 | 0/0 | 1 | 3 (2) | 24 (7) | 6 (1) | 45 (6) | 40 (12) |
| Arg453Cys | 2 | 66 (31) | NA | 0/0 | 0 | 4 | 23 | 4 | 45 | 62 |
| Actin binding (0) | ||||||||||
| Val404Leu | 12 | 46 (20) | 57 (25) | 2/2 | 0 | 2 (2) | 14 (6) | 2 (3) | 46 (7) | 37 (6) |
| Val411Ile | 1 | 62 | 65 | 0/0 | 1 | 6 | 18 | 5 | 34 | 39 |
| Actin binding (+) | ||||||||||
| Arg403Gln | 20 | 33 (21) | 50 (17) | 7/2 | 4 | 3 (2) | 17 (7) | 3 (4) | 48 (9) | 45 (11) |
| Light chain binding (+) | ||||||||||
| Gly716Arg | 2 | 50 (35) | NA | 0/0 | 0 | 7 | 23 | 8 | 51 | 48 |
| Rod (0) | ||||||||||
| Leu908Val | 21 | 42 (23) | 62 (17) | 2/1 | 2 | 3 (3) | 18 (8) | 3 (3) | 39 (3) | 38 (10) |
| Rod (+) | ||||||||||
| Arg870Cys | 5 | 45 (7) | 52 (7) | 3/0 | 1 | 4 (0) | 16 | 7 | 42 | 38 |
| Glu930Lys | 2 | 35 (16) | NA | 0/0 | 1 | 3 (2) | 21 (1) | 6 (1) | 47 (1) | 49 (1) |
| Total | 74 | 41 (21) | 56 (17) | 15/5 | 10 | 3 (2) | 18 (7) | 4 (3) | 44 (6) | 42 (10) |