Baseline characteristics by severity of mitral regurgitation (MR)
| No MR (n=179) | Mild MR (n=192) | Moderate to severe MR (n=244) | P value | |
| Age (years), mean (SD) | 66 (10) | 70 (10) | 71 (11) | <0.0001 |
| Male, n (%) | 177 (99) | 184 (96) | 240 (98) | 0.1 |
| Body surface area (m2), mean (SD) | 2.1 (0.3) | 2.0 (0.2) | 2.0 (0.2) | 0.0001 |
| Systolic blood pressure (mm Hg), mean (SD) | 123 (21) | 123 (20) | 119 (20) | 0.076 |
| Diastolic blood pressure (mm Hg), mean (SD) | 71 (12) | 73 (15) | 70 (14) | 0.16 |
| Hypertension, n (%) | 142 (79) | 161 (84) | 195 (80) | 0.489 |
| Diabetes mellitus, n (%) | 73 (41) | 95 (49) | 93 (38) | 0.051 |
| Atrial fibrillation, n (%) | 52 (29) | 65 (34) | 100 (41) | 0.035 |
| History of CAD, n (%) | 112 (63) | 139 (72) | 175 (72) | 0.068 |
| History of CABG surgery, n (%) | 42 (24) | 73 (38) | 78 (32) | 0.041 |
| Diuretic use, n (%) | 89 (50) | 110 (57) | 167 (68) | <0.001 |
| ACE inhibitor use, n (%) | 123 (69) | 142 (74) | 119 (49) | <0.001 |
| ARB use, n (%) | 17 (9.6) | 18 (9.4) | 39 (16) | 0.072 |
| Beta-blocker use, n (%) | 155 (88) | 158 (82) | 200 (82) | 0.235 |
| Glomerular filtration rate (mL/min/1.73 m2), mean (SD) | 94 (44) | 78 (39) | 67 (34) | <0.0001 |
| History of implantable cardioverter defibrillator, n (%) | 38 (21) | 42 (22) | 54 (22) | 0.975 |
| History of biventricular pacemaker implant, n (%) | 20 (11) | 21 (11) | 22 (9) | 0.716 |
| Statin use, n (%) | 139 (78) | 157 (82) | 164 (67) | 0.002 |
| Cardiomyopathy | ||||
| Ischaemic cardiomyopathy, n (%) | 111 (62) | 130 (68) | 157 (64) | 0.729 |
| Non-ischaemic cardiomyopathy, n (%) | 52 (29) | 48 (25) | 59 (24) | |
| Mixed cardiomyopathy, n (%) | 8 (5) | 6 (3) | 12 (5) | |
| Unknown cause of cardiomyopathy, n (%) | 8 (4) | 8 (4) | 16 (7) | |
| LVIDd (cm), mean (SD) | 5.7 (0.7) | 5.7 (0.8) | 5.9 (0.8) | 0.0007 |
| LVIDs (cm), mean (SD) | 4.7 (0.8) | 4.8 (0.8) | 5.1 (0.9) | <0.0001 |
| Left atrial dimension (cm), mean (SD) | 4.1 (0.6) | 4.2 (0.6) | 4.5 (0.6) | <0.0001 |
| Left atrial volume indexed to body surface area (mL/m2) | ||||
| Normal left atrial size (LAVI<29 mL/m2), n (%) | 67 (38) | 44 (23) | 20 (8) | < 0.0001 |
| Mildly dilated LA (LAVI 29–33 mL/m2), n (%) | 59 (33) | 49 (26) | 56 (23) | |
| Moderately dilated (LAVI 34–39 mL/m2), n (%) | 30 (17) | 54 (28) | 75 (31) | |
| Severely dilated (LAVI≥40 mL/m2), n (%) | 22 (12) | 44 (23) | 92 (38) | |
| LVEF (%), median (25%, 75%) | 30 (26, 33) | 28 (23, 33) | 25 (20, 33) | <0.0001 |
| Pulmonary artery systolic pressure (mm Hg), mean (SD) | 28 (9) | 31 (12) | 37 (12) | <0.0001 |
| Pulmonary venous systolic flow reversal, n (%) | 18 (11) | 43 (23) | 60 (25) | <0.001 |
| Tricuspid regurgitation | ||||
| None, n (%) | 130 (73) | 98 (51) | 53 (22) | < 0.001 |
| Mild, n (%) | 33 (18) | 62 (32) | 75 (31) | |
| Moderate, n (%) | 11 (6) | 23 (12) | 80 (33) | |
| Severe, n (%) | 5 (3) | 8 (4) | 35 (14) | |
ARB, angiotensin receptor blocker; CAD, coronary artery disease; CABG, coronary artery bypass graft; LA, left atrial; LAVI, LA volume indexed to body surface area (LA volume could not be measured in one person in each group); LVEF, left ventricular ejection fraction; LVIDd, left ventricular internal dimension at end diastole; LVIDs, left ventricular internal dimension at end systole.