Study design, participants and inclusion criteria for patients with non-LBBB QRS morphology who did or did not receive CRT
| Study | Design | Date | Country | Sample size | Age | Sex | Participant inclusion criteria |
|---|---|---|---|---|---|---|---|
| MADIT-CRT5 15 20 | Randomised controlled trial | December 2004 to September 2013 | 88 centres in USA, Canada and Europe | 1820 total: 1281 LBBB, 536 non-LBBB, 3 unknown | Total mean 64 years; non-LBBB mean 64 years | Total 75% male; non-LBBB 90% male | Age >21 years with ischaemic (NYHA I–II) or non-ischaemic (NYHA II) cardiomyopathy, sinus rhythm, QRS≥130 msec and LVEF ≤30% |
| CARE-HF1 18 | Randomised controlled trial | January 2001 to March 2003 | 82 European centres | 775 total: 730 LBBB, 45 non-LBBB | Total mean 67 years | Total 73% male | Age ≥18 years with NHYA III–IV, LVEF ≤35%, height-adjusted LVEDD ≥30 mm, QRS≥120 msec and sinus rhythm (additional dyssynchrony criteria required for QRS 120–149 msec) |
| COMPANION2 | Randomised controlled trial | January 2000 to November 2002 | 128 US centres | 1520 total: 1075 LBBB, 444 non-LBBB. | Total mean 67 years | Total 67% male | NHYA class III–IV ischaemic or non-ischaemic cardiomyopathy, sinus rhythm, QRS ≥120 msec, LVEF ≤35% and HF hospitalisation within preceding 12 months |
| RAFT4 12 | Randomised controlled trial | January 2003 to February 2009 | 34 centres in Canada, Europe, Turkey and Australia | Total 1798: 1295 LBBB, 503 non-LBBB | Total mean 66 years | Total 83% male | NYHA II–III ischaemic or non-ischaemic cardiomyopathy, LVEF ≤30%, QRS duration ≥120 msec (or paced QRS ≥200 msec) |
| REVERSE6 14 | Randomised controlled trial | September 2004 to September 2006 | 73 centres in USA, Canada and Europe | Total 610: 369 LBBB, 238 non-LBBB, 3 unknown | Total 63 years; non-LBBB 63 years | Total 79%. Non-LBBB 88% male | NHYA I–II, sinus rhythm, QRS ≥120 msec, LVEF ≤40%, LVEDD ≥55 mm |
6MWT, 6-min walk test; CRT, cardiac resynchronisation therapy; HF, heart failure; LBBB, left bundle branch block; LVEDD, left ventricular end-diastolic dimension; NYHA, New York Heart Association.