Table 2.
Echocardiography and Treadmill Exercise Data in the Study Population.
| Body mass index (kg/m2) |
P value |
||
|---|---|---|---|
| <30 (n=154) |
≥30 (n=88) |
||
| Left ventricular morphology | |||
| Septal wall thickness, basal segment (mm) | 18.6±5.1 | 19.4±4.4 | 0.21 |
| Septal wall thickness, mid segment (mm) | 18.7±6.2 | 19.1±6.5 | 0.62 |
| Maximal septal wall thickness (mm) | 20.5±0.6 | 21.4±0.5 | 0.22 |
| Posterior wall thickness (mm) | 10.9±2.7 | 11.9±3.1 | 0.01 |
| Septal/Posterior wall thickness ratio | 1.95±0.6 | 1.89±0.6 | 0.46 |
| LV mass index (g/m2.7) | 58±22 | 67±23 | 0.003 |
| LV end-diastolic volume index (ml/ m2.7) | 23.4±7 | 26.2±8 | 0.007 |
| LV end-systolic volume index (ml/ m2.7) | 8.1±3.5 | 9.2±3.6 | 0.02 |
| Stroke Volume Index (ml/ m2.7) | 15.3±4.9 | 17±6 | 0.03 |
| Relative wall thickness | 2±0.6 | 2±0.6 | 0.68 |
| Left ventricular function | |||
| E/A ratio | 1.32±0.6 | 1.20±0.4 | 0.13 |
| Septal mitral annulus early diastolic velocity (Em, cm/s) | 4.3±1.7 | 4.2±1.5 | 0.70 |
| E/Em ratio | 22.6±12.6 | 22.3±9.8 | 0.87 |
| Left atrial volume index (g/m2) | 38.7±21.7 | 36.5±13.5 | 0.38 |
| LV ejection fraction (%) | 66±9 | 65±10 | 0.24 |
| Global longitudinal systolic strain (%) | −15±3 | −15±3 | 0.41 |
| Left ventricular outflow tract parameters | |||
| LV outflow tract diameter (cm) | 2.1±0.3 | 2.2±0.3 | 0.15 |
| LV outflow tract peak gradient at rest (mmHg) | 27±33 | 25±28 | 0.72 |
| LV outflow tract peak gradient during Valsalva (mmHg) | 30±31 (n=134) |
39±40 (n=83) |
0.05 |
| LV outflow tract peak gradient during treadmill (mmHg) | 53±43 (n=120) |
66±57 (n=64) |
0.08 |
| LV outflow tract peak gradient during amyl nitrite inhalation (mmHg) | 41±41 (n=106) |
53±57 (n=61) |
0.11 |
| Maximal inducible LV outflow tract peak gradient (mmHg) | 55±46 (n=145) |
67±57 (n=86) |
0.09 |
| Dynamic LV outflow tract obstruction | |||
| - Non-obstructive | 40% | 28% | 0.06 |
| - Labile obstruction (stress-induced) | 33% | 46% | 0.06 |
| - Basal obstruction | 27% | 26% | 0.93 |
| Systolic anterior motion (SAM) of the mitral valve | |||
| - No SAM | 18% | 13% | 0.30 |
| - Incomplete SAM | 59% | 64% | 0.59 |
| - Complete SAM | 23% | 23% | 0.95 |
| Treadmill exercise | (n=117) | (n=66) | |
| Metabolic equivalents | 10.6±4.2 | 9±3.5 | 0.007 |
| Percentage exercise predicted heart rate | 86% | 84% | 0.65 |
| Systolic blood pressure at peak exercise (mmHg) | 169±39 | 173±36 | 0.58 |
| Diastolic blood pressure at peak exercise (mmHg) | 82±22 | 80±16 | 0.53 |
| Chest pain | 9% | 20% | 0.04 |
| Shortness of breath | 48% | 49% | 0.90 |
| Arrhythmia | 2% | 0% | 0.57 |
| Exercise time (sec) for Bruce protocols | 603±184 (n=63) |
512±212 (n=34) |
0.03 |