Table 2.
Baseline Characteristics by Major Genotype Subgroups
| MYBPC3-HCM | MYH7-HCM | Genotype Negative | P | |
|---|---|---|---|---|
| No. | 23 | 17 | 48 | |
| Sex (male/female) | 13/10 | 7/10 | 27/21 | NS |
| Age, diagnosis (y), median (IQR) | 37 (23-45) | 37 (13-45) | 52 (33-64) | .003 |
| Age, myectomy (y), median (IQR) | 38 (30-53) | 43 (16-52) | 57 (44-67) | .003 |
| NYHA class III-IV, no. (%) | 19 (83) | 12 (71) | 35 (73) | NS |
| Family history of HCM, no. (%) | 11 (48) | 7 (41) | 8 (17) | .01 |
| Family history of SCD, no. (%) | 6 (26) | 1 (6) | 5 (10) | NS |
| Systolic BP (mm Hg), median (IQR) | 120 (110-122) | 118 (102-127) | 125 (113-137) | NS |
| Diastolic BP (mm Hg), median (IQR) | 70 (62-75) | 66 (57-70) | 74 (64-82) | .01 |
| Heart rate (beats/min), median (IQR) | 68 (60-73) | 70 (60-78) | 68 (59-76) | NS |
| Ejection fraction (%), median (IQR) | 70 (65-76) | 75 (75-80) | 73 (70-76) | NS |
| LV mass index (g/m2), median (IQR) | 192 (144-238) | 183 (130-258) | 171 (134-217) | NS |
| LV wall thickness (mm), median (IQR) | 24 (18-27) | 25 (18-29) | 21 (16-24) | NS |
| LV outflow tract MIG (mm Hg), median (IQR) | 40 (16-106) | 81 (70-121) | 64 (30-94) | NS |
| Interstitial fibrosis score moderate or severe, no. (%) | 5 (22) | 4 (24) | 13 (27) | NS |
| Endocardial fibrosis score moderate or severe, no. (%) | 15 (65) | 13 (76) | 30 (63) | NS |
BP = blood pressure; HCM = hypertrophic cardiomyopathy; IQR = interquartile range; LV = left ventricular; MIG = maximum instantaneous gradient; MYBPC3 = myosin binding protein C; MYH7 = beta myosin heavy chain; NS = not significant; NYHA = New York Heart Association; SCD = sudden cardiac death.