Table 2.
CRT Trials in Mildly Symptomatic Heart Failure (NYHA Functional Classes I and II)
| Study | n | Inclusion Criteria | Design | Blinding | Control | Intervention | Follow-Up | Primary End Point | Response |
|---|---|---|---|---|---|---|---|---|---|
| Contak CD (6) | SeeTable1 | ||||||||
| MIRACLE-ICD 2 (9) | 186 | NYHA functional class II, LVEF ≤ 35%, QRS ≥ 130 ms, LVEDD ≥ 55 mm, ICD indicated, SR |
Parallel | Double blind | CRT-D (CRT-Off) | CRT-D (CRT-On) | 6 months | Change in peak VO2 | ↑ Peak VO2 (p = 0.87) |
| REVERSE (10) | 610 | NYHA functional class I or II, QRS ≥ 120 ms, LVEF ≤ 40%, LVEDD ≥ 55 mm, SR |
Parallel | Double blind | CRT-D (CRT-Off) | CRT-D (CRT-On) | 24 months | HF clinical composite score (worsening) |
19% vs. 34% (p = 0.01) |
| MADIT-CRT (8) | 1,820 | NYHA functional class I or II, LVEF ≤ 30%, QRS ≥ 130 ms, SR |
3:2 | Single blind | ICD | CRT-D | 2.4 yr (mean) | All-cause mortality or nonfatal HF |
HR: 0.66 (95% CI: 0.52− 0.84; p = 0.001) |
| RAFT (7) | 1,798 | NYHA functional class II (80%) or III (20%), LVEF ≤ 30%, QRS ≥ 120 ms |
Parallel | Double blind | CRT-D (CRT-Off) | CRT-D (CRT-On) | 40 months (mean) | All-cause mortality or HF hospitalization |
HR: 0.75 (95% CI: 0.64− 0.87; p < 0.001) |
MADIT-CRT = Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy; RAFT = Resynchronization/Defibrillation for Ambulatory Heart Failure Trial; REVERSE = Resynchronization Reverses Remodeling in Systolic Left Ventricular Dysfunction; other abbreviations as in Table 1.