Cardiac resynchronization therapy beyond nominal settings: who needs individual programming of the atrioventricular and interventricular delay?

Compared with the best of the currently available device nominal AV and VV delays, 23–45% of CRT patients can yield additional acute haemodynamic effect by individual optimization of the delays. A new nominal VV delay of 40 ms LV pre-activation is recommended. Male gender, ischaemic aetiology, and longer PR interval are associated with a larger effect of individual optimization