Figure 4From: Shortening of atrioventricular delay at increased atrial paced heart rates improves diastolic filling and functional class in patients with biventricular pacing Increased atrial pacing rate requires progressive shortening of AV delay. After baseline AV delay optimization shown in Figure 1, atrial pacing rate was increased to 70 beats/min, and AV delay was kept fixed at 190 ms. Marked E and A fusion developed (A). AV delay was then progressively shortened to 120 ms until E and A separation occurred (C). Hence, optimal AV delay at a paced atrial rate of 70 beats/min was 120 ms.Back to article page