Selection criteria for cardiac resynchronization therapy (CRT)
Following are the current selection criteria for cardiac resynchronization therapy (CRT; also known as heart failure device or biventricular pacing):
1. Severe heart failure (New York Heart Association (NYHA) class III or IV)
2. Depressed left ventricular ejection fraction (LVEF) (<35%)
3. QRS showing a left bundle branch block configuration with a duration ≥120 ms
4. Should be in sinus rhythm
5. Should be on optimal medical therapy
Those with recent myocardial infarction or have undergone coronary revascularisation within 3 months as well as those scheduled for coronary revascularisation are excluded. This is in view of the potential for improvement in left ventricular function in the short term.