Ricci Renato, Pignalberi Carlo, Ansalone Gerardo, Jannone Enzo, Vaccaro Maria Vittoria, Denaro Alessandra, Cavaglià Sergio, Santini Massimo
Department of Cardiology, S. Filippo Neri Hospital, Via Martinotti, 20-00135 Rome, Italy.
J Interv Card Electrophysiol. 2002 Jul;6(3):279-85. doi: 10.1023/a:1019570022647.
48 patients (40 Male), mean age 68 +/- 8 years, in III-IV class, with intraventricular conduction delay, received a biventricular pacemaker. Heart failure aetiology was non-ischemic in 60%. Left ventricular lead positioning was inferior in 5 patients (10%), posterior in 12 (25%), lateral in 18 (37%) and anterior in 13 (27%). QRS duration and axis were evaluated in sinus rhythm, and during right ventricular pacing, left ventricular pacing and biventricular pacing, the last early after implant and late after 8.8 +/- 4.3 months. QRS duration (ms) was 154 +/- 29 in sinus rhythm, 175 +/- 28 during right ventricular pacing, 196 +/- 31 during left ventricular pacing, 122 +/- 23 during biventricular pacing "early" and 120 +/- 18 during biventricular pacing "late." All the differences were statistically significant, but not between "early" and "late" biventricular pacing. Mean QRS axis ( degrees ) was -27 +/- 32 in sinus rhythm, -75 +/- 4 during right ventricular pacing, 112 +/- 41 during left ventricular pacing, -82 +/- 51 during biventricular pacing "early" and -80 +/- 42 during biventricular pacing "late." Only the difference between left ventricular pacing and all the other groups was statistically significant. QRS axis did not significantly differ according to left ventricular lead site during left and biventricular pacing. "Late" compared with "early" biventricular pacing axis showed variation >30 degrees in 35% of patients, in spite of no significant changes in QRS duration and x-ray positioning.
Biventricular pacing significantly reduced QRS width, which persisted long-term. Left and biventricular pacing axis was poorly related to left ventricular lead positioning. Biventricular pacing axis variability over time may suggest a role of electrical remodeling.
48例患者（40例男性），平均年龄68±8岁，心功能Ⅲ - Ⅳ级，伴有室内传导延迟，接受了双心室起搏器植入。60%的患者心力衰竭病因是非缺血性的。左心室导线定位为下壁5例（10%），后壁12例（25%），侧壁18例（37%），前壁13例（27%）。在窦性心律、右心室起搏、左心室起搏和双心室起搏期间评估QRS时限和电轴，双心室起搏评估在植入后早期以及8.8±4.3个月后的晚期进行。窦性心律时QRS时限（毫秒）为154±29，右心室起搏时为175±28，左心室起搏时为196±31，双心室起搏“早期”为122±23，双心室起搏“晚期”为120±18。所有差异均具有统计学意义，但双心室起搏“早期”和“晚期”之间无差异。平均QRS电轴（度）在窦性心律时为 - 27±32，右心室起搏时为 - 75±4，左心室起搏时为112±41，双心室起搏“早期”为 - 82±51，双心室起搏“晚期”为 - 80±42。仅左心室起搏与其他所有组之间的差异具有统计学意义。在左心室起搏和双心室起搏期间，QRS电轴根据左心室导线位置无显著差异。尽管QRS时限和X线定位无显著变化，但与双心室起搏“早期”相比，“晚期”双心室起搏电轴在35%的患者中变化>30度。
双心室起搏显著降低QRS宽度，且长期持续存在。左心室起搏和双心室起搏电轴与左心室导线定位关系不大。双心室起搏电轴随时间的变化可能提示电重构的作用。
