Pap Róbert, Gallardo Rodrigo, Rónaszéki Dóra, Ágoston Gergely, Traykov Vassil B, Sághy László, Varga Albert, Forster Tamás
2nd Department of Medicine and Cardiology Centre, University of Szeged, Szeged, Hungary.
2nd Department of Medicine and Cardiology Centre, University of Szeged, Szeged, Hungary.
J Electrocardiol. 2012 Jul-Aug;45(4):357-360. doi: 10.1016/j.jelectrocard.2012.04.001. Epub 2012 May 1.
Patients with atrioventricular (AV) block can develop left ventricular (LV) dysfunction with long-term right ventricular pacing (RVP). We investigated the role of RVP-induced LV dyssynchrony in this adverse remodeling.
Nineteen patients with normal LV function undergoing pacemaker implantation for AV block were included. Right ventricular pacing leads were positioned at the apex. Two-dimensional and tissue Doppler echocardiography was performed before and immediately after implantation and at the end of follow-up. The maximal delay between peak velocities of opposing basal LV walls was measured using tissue Doppler echocardiography, as an index of LV dyssynchrony. With the initiation of RVP, LV dyssynchrony increased in some patients and decreased in others, as compared with intrinsic rhythm. The RVP-induced change in dyssynchrony inversely correlated with baseline dyssynchrony (r = -0.686, P = .010). After 28 ± 3.6 months, LV end-systolic volume (ESV) increased, and ejection fraction decreased (from 34 ± 12 to 40 ± 20 mL, P = .010 and from 65% ± 6% to 56% ± 11%, P < .001, respectively). The change in LV ESV was greater in patients with 60% or greater cumulative RVP (9.9 vs 0.08 mL, P = .027). Within this frequently paced group, the RVP-induced change in dyssynchrony correlated with the increase in LV ESV (r = 0.727, P = .026). Patients who had a 15% or greater increase in LV ESV had greater RVP-induced change in dyssynchrony (28.4 vs -7.8 milliseconds, P = .037).
Some patients with AV block experience an increase in LV dyssynchrony with RVP. Increased LV dyssynchrony predicts adverse LV remodeling during long-term follow-up.
房室（AV）传导阻滞患者长期右心室起搏（RVP）可导致左心室（LV）功能障碍。我们研究了RVP诱导的LV不同步在这种不良重塑中的作用。
纳入19例因AV传导阻滞接受起搏器植入且LV功能正常的患者。右心室起搏导线置于心尖。在植入前、植入后即刻及随访结束时进行二维和组织多普勒超声心动图检查。使用组织多普勒超声心动图测量左心室相对基底壁峰值速度之间的最大延迟，作为LV不同步的指标。与自身心律相比，开始RVP后，部分患者LV不同步增加，部分患者LV不同步减少。RVP诱导的不同步变化与基线不同步呈负相关（r = -0.686，P = 0.010）。28±3.6个月后，左心室收缩末期容积（ESV）增加，射血分数降低（分别从34±12 ml增至40±20 ml，P = 0.010；从65%±6%降至56%±11%，P < 0.001）。累积RVP达60%或更高的患者，LV ESV变化更大（9.9 vs 0.08 ml，P = 0.027）。在这个频繁起搏组中，RVP诱导的不同步变化与LV ESV增加相关（r = 0.727，P = 0.026）。LV ESV增加15%或更多的患者，RVP诱导的不同步变化更大（28.4 vs -7.8毫秒，P = 0.037）。
部分AV传导阻滞患者RVP时LV不同步增加。LV不同步增加预示长期随访期间LV不良重塑。
