Background
Methods
Patient selection
CMR protocol
CMR sequences
Evaluation of LV dimensions, function, mass and regional fibrosis
Evaluation of diffuse fibrosis with T1 mapping
Evaluation of diastolic function
Image analysis
Statistical methods
Results
Clinical and demographic data
HCM (n=51) | Control (n=25) | p value | |
---|---|---|---|
Age, y | 48 ± 14 | 48 ± 17 | 0.8 |
Males, n (%) | 39 (76%) | 18 (72%) | 0.7 |
Body mass index, kg/m2 | 27.5 ± 4.9 | 24.1 ± 2.7 | <0.001 |
Family history of HCM, n (%) | 17 (33%) | - | |
Symptoms, n (%) | |||
Chest pain | 16 (31%) | - | |
Dyspnoea | 28 (55%) | - | |
NYHA class I or II | 51 (100%) | - | |
Presyncope | 18 (35%) | - | |
Syncope | 6 (12%) | - | |
Medications, n (%) | |||
Beta-blocker | 29 (57%) | - | |
Calcium channel blocker | 10 (20%) | - | |
Resting heart rate, beats/min | 60 ± 10 | 62 ± 9 | 0.6 |
Systolic blood pressure, mm Hg | 129 ± 16 | 133 ± 18 | 0.4 |
Hematocrit | 0.43 ± 0.04 | 0.42 ± 0.03 | 0.3 |
eGFR, ml/min/1.73 m2 | 81 ± 12 | 86 ± 8 | 0.14 |
CMR findings
HCM (n=51) | Control (n=25) | p value | |
---|---|---|---|
LVEDV, ml | 162 ± 36 | 156 ± 35 | 0.5 |
LVEDV indexed, ml/BSA | 81 ± 14 | 83 ± 13 | 0.5 |
LVESV, ml | 50 ± 17 | 63 ± 18 | <0.01 |
LV stroke volume, ml | 112 ± 27 | 94 ± 20 | <0.01 |
LVEF, % | 70 ± 7 | 60 ± 6 | <0.001 |
LV mass, g | 178 ± 54 | 98 ± 25 | <0.001 |
LV mass indexed, g/BSA | 89 ± 25 | 52 ± 9 | <0.001 |
Septal thickness, mm | 20 ± 3 | 8 ± 2 | <0.001 |
Lateral wall thickness, mm | 9 ± 2 | 8 ± 1 | <0.05 |
Septal:lateral wall thickness | 2.3 ± 0.7 | 1.1 ± 0.9 | <0.001 |
Presence of LGE, n (%) | 43 (84%) | 0 (0%) | |
Quantity of LGE, % of LV mass | 6.1 ± 7.7 | 0 |
Post-contrast myocardial T1 time in HCM and control subject
HCM (n=51) | Control (n=25) | p value | |
---|---|---|---|
Post-contrast T1 time, ms | |||
LV myocardium, excluding LGE | 498 ± 80 | 561 ± 47 | <0.0001 |
LV myocardium, including LGE | 483 ± 85 | 561 ± 47 | <0.0001 |
LV blood pool | 304 ± 31 | 306 ± 22 | 0.8 |
Echocardiography findings
HCM (n=51) | Control (n=25) | p value | |
---|---|---|---|
Left atrial volume indexed, ml/m2 | 51 ± 18 | 32 ± 10 | <0.001 |
Resting LVOT gradient, mm Hg | 26 ± 36 | 4 ± 1 | <0.001 |
Mitral E velocity, cm/s | 0.8 ± 0.2 | 0.7 ± 0.2 | 0.1 |
Mitral A velocity, cm/s | 0.6 ± 0.3 | 0.6 ± 0.2 | 0.5 |
E/A ratio | 1.4 ± 0.6 | 1.4 ± 0.5 | 0.7 |
Deceleration time, ms | 217 ± 51 | 188 ± 36 | <0.01 |
Septal e’, cm/s | 6.0 ± 1.7 | 8.8 ± 3.0 | <0.001 |
Lateral e’, cm/s | 8.3 ± 2.6 | 12.0 ± 4.0 | <0.001 |
Mean e’, cm/s | 7.1 ± 1.9 | 10.4 ± 3.3 | <0.001 |
Septal E/e’ ratio | 14.4 ± 5.8 | 8.9 ± 3.2 | <0.001 |
Lateral E/e’ ratio | 10.6 ± 4.7 | 6.4 ± 1.9 | <0.001 |
Mean E/e’ ratio | 12.5 ± 4.9 | 7.7 ± 2.4 | <0.001 |
Correlates of post-contrast myocardial T1 time in HCM patients
Simple linear regression | Multiple linear regression | |||
---|---|---|---|---|
r | p value | β | p value | |
Age | −0.41 | <0.01 | −0.34 | 0.02 |
Male | −0.14 | 0.3 | ||
Body mass index | −0.35 | <0.05 | −0.24 | 0.08 |
Family history of HCM | 0.20 | 0.2 | ||
Presence of symptoms | −0.17 | 0.2 | ||
NYHA class | −0.16 | 0.3 | ||
Resting heart rate | 0.13 | 0.4 | ||
Systolic blood pressure | −0.12 | 0.4 | ||
Diastolic blood pressure | 0.12 | 0.4 | ||
Hematocrit | −0.29 | 0.11 | ||
eGFR | 0.26 | 0.3 | ||
Presence of LGE | 0.18 | 0.21 | ||
Quantity of LGE | −0.13 | 0.39 |
Correlates of diastolic dysfunction in HCM patients
Simple linear regression | Multiple linear regression | |||
---|---|---|---|---|
r | p value | β | p value | |
Baseline characteristics | ||||
Age | 0.33 | <0.05 | 0.11 | 0.4 |
Body mass index | 0.05 | 0.7 | ||
NYHA class | 0.20 | 0.15 | ||
CMR parameters | ||||
LVEDV indexed | 0.23 | 0.11 | ||
LVEF | −0.10 | 0.5 | ||
LV mass indexed | 0.30 | <0.05 | −0.10 | 0.6 |
Septal thickness | 0.28 | <0.05 | 0.31 | 0.05 |
Presence of LGE | −0.16 | 0.3 | ||
Quantity of LGE | 0.16 | 0.3 | ||
Post-contrast myocardial T1 time | −0.48 | <0.001 | −0.34 | 0.02 |
Echocardiography parameters | ||||
Left atrial volume indexed | 0.38 | <0.01 | 0.24 | 0.06 |
Resting LVOT gradient | 0.46 | <0.001 | 0.29 | 0.03 |