Background
Methods
Study design and cohort
Echocardiography
Cardiopulmonary exercise testing
Long-term follow-up and assessment of major adverse cardiac events
Statistical analyses
Results
Baseline results
Baseline (n = 205) | Six-month FU (n = 197) |
P-value | |
---|---|---|---|
Clinical
| |||
Age, mean ± SD (years) | 64.8 ± 12.4 | – | |
Male gender (%) | 142 (69) | – | |
Ischaemic cardiomyopathy (%) | 106 (52 %) | – | |
NYHA I (%) | 1 (0.5) | 16 (8.3) | 0.001 |
NYHA II (%) | 26 (12.7) | 104 (53.6) | 0.171 |
NYHA III (%) | 167 (81.5) | 71 (36.6) | 0.062 |
NYHA IV (%) | 11 (5.3) | 3 (1.5) | < 0.001 |
ECG
| |||
QRS duration, mean ± SD, ms | 166 ± 24 | 153 ± 24 | < 0.001 |
Left bundle branch block (%) | 116 (57) | – | |
Interventricular conduction delay (%) | 63 (31) | – | |
Right bundle branch block (%) | 1 (0.5) | – | |
QRS < 120 ms (%) | 1 (0.5) | – | |
Right ventricular pacing (%) | 23 (11) | – | |
Echocardiography
| |||
LVESV, median (IQR), ml | 180 (87) | 133 (95) | < 0.001 |
LVEDV, median (IQR), ml | 230 (92) | 182 (115) | < 0.001 |
LVEF, mean ± SD (%) | 21.6 ± 6.8 | 28.6 ± 10.4 | < 0.001 |
IVMD, mean ± SD (ms) | 46 ± 28 | 15 ± 28 | < 0.001 |
Exercise test
| |||
Peak VO2, mean ± SD (ml/kg/min) | 14.0 ± 4.2 | 15.4 ± 4.8 | < 0.001 |
Percentage of predicted peak VO2, mean ± SD (%) | 61.1 ± 18.8 | 67.4 ± 23.2 | < 0.001 |
VE/VCO2, median (IQR) | 38 (15) | 34 (11) | < 0.001 |
Laboratory tests
| |||
BNP, median (IQR), pmol/L | 112 (172) | 71 (107) | < 0.001 |
Creatinine, median (IQR), µmol/L | 112 (52) | 115 (53) | 0.002 |
Medication
| |||
Beta-blocker (%) | 157 (78) | – | |
ACE-inhibitor (%) | 152 (76) | – | |
Diuretics (%) | 180 (90) | – |
Six-month results
Long-term follow-up and major adverse cardiac events
Assessment of CRT response
Potential surrogate endpoints | MACE (n = 36) | Non-MACE (n = 154) |
P-value |
---|---|---|---|
∆ LVESV (%)
| − 9.5 ± 18.7 | − 23.5 ± 23.0 | < 0.001 |
∆ LVEF (absolute %)
| 3.5 ± 6.2 | 8.2 ± 9.0 | < 0.001 |
∆ IVMD (ms)
| − 29 ± 35 | − 34 ± 32 | 0.422 |
∆ QRS duration (ms)
| 4.0 ± 28.4 | 16.4 ± 26.3 | 0.022 |
∆ Peak VO
2
(ml/kg/min)
| 0.8 ± 3.0 | 1.1 ± 3.1 | 0.684 |
∆ Predicted peak VO
2
(absolute %)
| 5.7 ± 14.7 | 6.0 ± 14.8 | 0.930 |
∆ VE/VCO
2
slope
| − 2 (17) | − 4 (9) | 0.674 |
∆ BNP (pmol/L)
| 14.5 (125) | − 21.5 (106) | 0.019 |
∆ Creatinine (µmol/L)
| 0.5 (23) | − 4.8 (22) | 0.375 |
NYHA improvement (%)
| 12 (38) | 94 (63 %) | 0.009 |
Potential surrogate endpoints | Multivariable HR (CI) | ||
---|---|---|---|
Total population | NICM | ICM | |
∆ LVESV (%)
| 0.975 (0.960–0.991) | 0.960 (0.938–0.983) | – |
∆ LVEF (absolute %)
| – | – | – |
∆ VE/VCO
2
slope
| – | – | – |
∆ BNP (pmol/L)
| – | – | 0.993 (0.988–0.998) |
∆ NYHA (class)
| – | – | – |
Potential surrogate endpoints | MACE (n = 11) | Non-MACE (n = 74) |
P-value |
---|---|---|---|
∆ LVESV (%)
| − 2.4 ± 11.5 | − 30.0 ± 24.2 | < 0.001 |
∆ LVEF (absolute %)
| 3.5 ± 6.2 | 10.9 ± 9.3 | 0.013 |
∆ IVMD (ms)
| − 35 ± 37 | − 37 ± 34 | 0.832 |
∆ QRS duration (ms)
| 3.6 ± 28.0 | 17.6 ± 28.2 | 0.132 |
∆ Peak VO
2
(ml/kg/min)
| 2.2 ± 2.9 | 1.36 ± 3.5 | 0.615 |
∆ Predicted peak VO
2
(absolute %)
| 12.4 ± 15.1 | 6.7 ± 16.0 | 0.365 |
∆ VE/VCO
2
slope
| 10 (19) | 3 (6) | 0.049 |
∆ BNP (pmol/L)
| − 14 (360) | 32 (106) | 0.627 |
∆ Creatinine (µmol/L)
| 5.0 (29) | − 1.5 (22) | 0.159 |
NYHA improvement (%)
| 6 (60) | 50 (66) | 0.718 |
Potential surrogate end-points | MACE (n = 24) | Non-MACE (n = 71) |
P-value |
---|---|---|---|
∆ LVESV (%)
| − 12.7 ± 20.5 | − 16.8 ± 19.8 | 0.392 |
∆ LVEF (absolute %)
| 3.5 ± 6.3 | 5.5 ± 7.8 | 0.269 |
∆ IVMD (ms)
| − 26 ± 35 | − 31 ± 31 | 0.537 |
∆ QRS duration (ms)
| 4.3 ± 29.3 | 15.1 ± 24.3 | 0.101 |
∆ Peak VO
2
(ml/kg/min)
| 0.1 ± 2.8 | 0.8 ± 2.5 | 0.299 |
∆ Predicted peak VO
2
(absolute %)
| 2.7 ± 13.9 | 5.3 ± 13.6 | 0.496 |
∆ VE/VCO
2
slope
| 0.7 (18) | 4.4 (13) | 0.139 |
∆ BNP (pmol/L)
| 35 (77) | − 53 (78) | 0.041 |
∆ Creatinine (µmol/L)
| − 6.0 (27) | − 5.0 (22) | 0.673 |
NYHA improvement (%)
| 6 (27) | 44 (60) | 0.008 |