Background:
Different strategies have been investigated for optimization of atrioventricular (AV) synchrony in patients with dual chamber pacemakers (DDD), which has a crucial role in preserving an effective cardiac output. However, no consensus on the best modality in the shadow of interventricular dyssynchrony induced by right ventricular pacing which eventually worsens long-term cardiac performance.
Aim:
To utilize the Left ventricular 2D speckle tracking strain parameters as a new tool guiding atrioventricular delay (AVD) synchronization in patients with DDD pacemaker to achieve the best LV systolic performance.
Methods:
This interventional cross-over study involved 255 patients with DDD pacemakers, with mean age 50.62 ± 7.03 years, 175 of them were males 68.6% and 80 were females 31.4%. Each device was programmed to 4 different AV intervals, at one-week interval each; (AVpacing /AV sensenig):120/100 ,150/130 ,180/160, 200/180 msec). Conventional echocardiographic parameters & left ventricular (LV) 2D speckle tracking (ST) strain were interrogated.
Results:
At relatively prolonged AVD (180/160 msec), both LV longitudinal strain and left ventricular outflow tract velocity time integral (LVOT VTI) were significantly improved (18.11±1.35 & 27.19 ± 3.16 respectively with P