Table 3.
2011 update of CRT guidelines from the Heart Failure Society of America70
| Recommendation | QRS duration (ms) | NYHA class | LVEF | Strength of evidence |
|---|---|---|---|---|
| CRT is recommended for patients in sinus rhythm with a widened QRS interval that is not a result of right bundle branch block, who have severe LV systolic dysfunction and persistent, mild-to-moderate HF despite optimal medical therapy | ≥150 | II–III | ≤35% | A |
| CRT can be considered for ambulatory, severely symptomatic patients with HF and a widened QRS interval and LV systolic dysfunction despite optimal medical therapy | ≥150 | IV | ≤35% | B |
| CRT can be considered for patients with a widened QRS interval and severe LV systolic dysfunction who have persistent, mild-to-severe HF despite optimal medical therapy | ≥120 to <150 | II–IV | ≤35% | B |
| CRT can be considered for patients with atrial fibrillation with a widened QRS interval and severe LV systolic dysfunction who have persistent, mild-to-moderate HF despite optimal medical therapy | ≥120 | II–III | ≤35% | B |
| In patients with a reduced LVEF who require chronic pacing and in whom frequent ventricular pacing is expected, CRT can be considered | No comment | No comment | No comment | C |
Abbreviations: CRT, cardiac resynchronization therapy; HF, heart failure; LV, left ventricular; LVEF, left ventricular ejection fraction. Adapted from J. Card. Fail. 12 (2), Stevenson, W. G. et al. Indications for cardiac resynchronization therapy: 2011 update from the Heart Failure Society of American Guideline Committee, 94–106 © (2012), with permission from Elsevier.