Introduction .– It is well known that right ventricular pacing (VP) can alter left ventricular (LV) function. But few are known in ability of LV recovery after VP.

Objectives .– The aim of this study is to evaluate LV function with 2D strain imaging after 2 months of right VP, immediately and at 2 weeks after stopping VP.

Population and methods .– Population consisted of 20 pts (12 women, mean age 68.6 ± 12, QRS < 120 ms, PR > 120 ms, normal LV ejection fraction) implanted for sinus node dysfunction with dual chamber pace maker(VP < 10%). Five TTE (GE Vivid 7 and Vivid 9) were performed at day 0 (D0) with AAI mode (AAI1) then DDD mode (DDD1), at day 60 (D60) with DDD (DDD2) then AAI mode (AAI 2) and 2 weeks after the end of VP at D75 (AAI 3). LV function was analyzed by global longitudinal strain (GLS) (Speckle tracking). Between D0 and D60, all pts were programmed in DDD with VP > 90%.

Results .– LS decrease significantly at D0 between AAI1 and DDD1(−19,15 ± 3,4 vs −16,87 ± 4,1 P = 0.004)but after 2 months of VP (D0–D60), LS is not significantly modified(−16.87 ± 4,1 vs −14,67 ± 8,1, P = 0.63). At D60 between DDD2 and AAI2, GLS is increased (−14,67 ± 8,1 vs −17,99 ± 2,4 P = 0.048). Between D60 (AAI2) and D75 (AAI3) there is no more significative increase in GLS (−17,99 ± 2,4 vs −18,06 ± 2,7, P = 0,9).

Conclusion .– Longitudinal strain decreases immediately after VP, and recovers immediately after stopping VP. We didn’t find any midterm evolution in GLS. Further studies are needed on a longer period of time to determine if recovery kinesis of GLS is modified with a longer period of pacing.