特发性室性早搏负荷及起源位置对左心功能的影响

Effect of burden and origin of idiopathic premature ventricular contractions on left cardiac function

目的探讨室性早搏（premature ventricular contractions，PVCs）负荷和起源对左心功能的影响及其相关因素。方法对我中心在2012年4月至2013年3月收治的91例特发性PVCs患者按照下述方法分组。根据PVCs负荷将所有91例患者分为A1组（PVCs负荷6%~19%）和A2组（PVCs负荷20%~54%）；按导管消融术标测的PVCs起源部位将73例患者分为右室流出道B1、右室非流出道B2、左室流出道B3和左室非流出道B4四组。对各亚组左心结构与功能参数进行统计分析。结果高负荷A2组的左房双期容积（LAVmax、LAVmin）、氮末端-脑利钠肽前体（NT-proBNP）显著高于低负荷A1组（P〈0.05）；PVCs负荷与左房双期容积以及NT-proBNP均呈显著正相关（rs=0.229,0.261,0.361,P均〈0.05），PVCs负荷与左室射血分数（left ventricular ejection fraction, LVEF）呈显著负相关（r=-0.227, P=0.03）；左室起源组较右室起源组有更大的左室/左房直径，即：左室舒张末期直径（left ventricular end-diastolic diameter, LVEDD） [（51.7±6.3） mm vs （48.3±5.0） mm, P=0.024]以及左房最大直径（LADmax）[（36.2±4.4） mm vs 33.1±4.7 mm, P=0.012]；右室流出道B1组的LAVmax较右室非流出道B2组更大[（43.5±12.9） mL vs （32.7±8.4） mL， P=0.040]，左室流出道B3组的LADmax显著大于右室流出道B1组和右室非流出道B2组（P〈0.01）。结论PVCs负荷和/或起源部位影响左心功能，左房受到的影响可能发生更早。

Objective To explore the effect of the burden and origin of idiopathic premature ventricular contractions （PVCs） on left heart structure and function. Methods Ninety-one consecutive patients with idiopathic PVCs treated in our center between April 2012 and March 2013 were divided into group A1 （6% to 19%） and group A2 （20% to 54%） according to PVC burden. Seventy-three patients after catheter ablation were further divided into 4 groups according to PVC origin, including right ventricular outflow tract group B1, right ventricular non-outflow tract group B2, left ventricular outflow tract group B3 and left ventricular non-outflow tract group B4. The parameters of left cardiac structure and function in each subgroup were analyzed with statistical methods. Results The double phase volume of left atrium （LAVmax and LAVmin） and the level of N-terminal pro-brain natriuretic peptide （NT-proBNP） in group A2 were significantly higher than those in group A1 （P〈0.05）. PVC burden had positive correlation with LAVmax/LAVmin and NT-proBNP level （rs=0.229, 0.261, 0.361, P〈0.05）, and had negative correlation with left ventricular ejection fraction （LVEF） （r=-0.227, P=0.03）. Comparing to groups B1 and B2 from right ventricular origin, groups B3 and B4 from left ventricular origin had larger diameters of left atrium and left ventricular, with left ventricular end-diastolic diameter （LVEDD） of 51.7±6.3 mm vs 48.3±5.0 mm （P=0.024） and left atrial maximum diameter （LADmax） of 36.2±4.4 mm vs 33.1±4.7mm （P=0.012）. LAVmax in right ventricular outflow tract group B1 was larger than that in right ventricular non-outflow tract group B2 （43.5±12.9 mL vs 32.7±8.4 mL, P=0.040）. The diameter LADmax in left ventricular outflow tract group B3 was significantly longer than in right ventricular outflow tract group B1 and that in right ventricular non-outflow tract group B2 （P〈0.01）. Conclusion The effects of PVC burden and/or origin on the structure and function of left atrium are different from those on left ventricular, while left atrium seems to be more sensitive to the effects.