Table 1.
Baseline patient characteristics
| Characteristic | All patients N = 34 |
Initial CRT responders N = 15 |
Initial CRT nonresponders N = 19 |
|---|---|---|---|
| Male, n (%) | 19 (56) | 7 (50) | 12 (63) |
| Age, y (range) | 74 (60-93) | 74 (60-89) | 75 (63-93) |
| Time since implant in mo, mean (range) | 17.8 ± 8.5 | 16.5 ± 9.3 | 17.8 ± 7.2 |
| Ischemic cardiomyopathy, n (%) | 21 (62) | 6 (40) | 15 (79) |
| Hypertension | 28 (82) | 14 (93) | 14 (78) |
| Diabetes mellitus | 8 (24) | 4 (27) | 4 (21) |
| Paroxysmal atrial fibrillation | 10 (29) | 3 (20) | 7 (37) |
| Left bundle branch block | 31 (91)∗ | 15 (100) | 16 (84) |
| CRT defibrillator | 22 (65) | 10 (67) | 12 (63) |
| NYHA, n (%)† | |||
| I | 4 (11.8) | 1 (7) | 3 (16) |
| II | 24 (70.6) | 14 (93) | 10 (53) |
| III | 6 (17.6) | 0 (0) | 6 (31) |
| QRSd (ms) | 163.5 ± 24.3 | 168.1 ± 17.3 | 158.9 ± 29.1 |
| Intrinsic PR interval (ms) | 187.2 ± 36.6 | 184.9 ± 21.1 | 187.3 ± 46.5 |
| LVEF (%) before initial CRT | 24.1 ± 10.1 | 24.9 ± 9.4 | 23.7 ± 10.5 |
| LVEF (%) before SyncAV | 30.9 ± 13.3 | 41.1 ± 9.6 | 23.4 ± 10.6 |
| LVEDV (mL)† | 157.5 ± 56.6 | 133.4 ± 43.5 | 174.1 ± 59.7 |
| LVESV (mL)† | 110.5 ± 57.5 | 75.6 ± 31.8 | 134.5 ± 59.7 |
| Left atrial diameter (cm) | 43.3 ± 7.0 | 42.5 ± 6.6 | 43.9 ± 7.5 |
| Medical therapy for heart failure | |||
| ACEI/ARB | 28 (82) | 12 (80) | 16 (84) |
| β-Blocker | 28 (82) | 12 (80) | 16 (84) |
| MRA | 5 (15) | 2 (13) | 3 (16) |
ACEI, angiotensin-converting enzyme inhibitor; ARB, angiotensin receptor blocker; CRT, cardiac resynchronization therapy; LVEDV, left ventricular end-diastolic volume; LVEF, left ventricular ejection fraction; LVESV, left ventricular end-systolic volume; MRA, magnetic resonance angiography; NYHA, New York Heart Association; QRSd, QRS duration.
Modified from AlTurki et al.14 with permission from Elsevier.
∗
The remaining 3 were bifascicular block (right bundle branch block and left anterior fascicular block or left posterior fascicular block).
†
Before SyncAV ECG optimization.