DE Pooter Jan, El Haddad Milad, DE Buyzere Marc, Aranda Hernandez Alfonso, Cornelussen Richard, Stegemann Berthold, Rinaldi Christopher A, Sterlinski Maciej, Sokal Adam, Francis Darrel P, Jordaens Luc, Stroobandt Roland X, VAN Heuverswyn Frederic, Timmermans Frank
Ghent University Hospital, Heart Center, Ghent, Belgium.
Medtronic Plc, Bakken Research Center, Maastricht, The Netherlands.
J Cardiovasc Electrophysiol. 2017 Feb;28(2):192-200. doi: 10.1111/jce.13132. Epub 2016 Dec 19.
Vectorcardiographic (VCG) QRS area of left bundle branch block (LBBB) predicts acute hemodynamic response in cardiac resynchronization therapy (CRT) patients. We hypothesized that changes in QRS area occurring with biventricular pacing (BV) might predict acute hemodynamic CRT response (AHR).
VCGs of 624 BV paced electrocardiograms (25 LBBB patients with 35 different pacing configurations) were calculated according to Frank's orthogonal lead system. Maximum QRS vector amplitudes (X , Y , Z , and 3D ) and QRS areas (X , Y , Z , and 3D ) in the orthogonal leads (X, Y, and Z) and in 3-dimensional projection were measured. Volume of the 3D vector loop and global QRS duration (QRSD) on the surface electrocardiogram were assessed. Differences (Δ) in VCG parameters between BV paced and LBBB QRS complexes were calculated. An increase of 10% in dP/dt max was considered as AHR. LBBB conduction is characterized by a large Z (109 μVs, interquartile range [IQR]:75;135), significantly larger than X (22 μVs, IQR:10;57) and Y (44 μVs, IQR:32;62, P < 0.001). Overall, QRS duration, amplitudes, and areas decrease significantly with BV pacing (P < 0.001). Of all VCG parameters, 3D , Δ3D , Z ΔZ , Δ3D , and ΔQRSD differentiate AHR response from nonresponse (P < 0.05). ΔZ predicted best positive AHR (area under the curve = 0.813) and outperformed any other VCG parameter or QRSD measurement.
Of all VCG parameters, reduction in QRS area, calculated in Frank's Z lead, predicts acute hemodynamic response best. This method might be an easy, noninvasive tool to guide CRT implantation and optimization.
左束支传导阻滞（LBBB）患者的心向量图（VCG）QRS面积可预测心脏再同步治疗（CRT）患者的急性血流动力学反应。我们假设双心室起搏（BV）时QRS面积的变化可能预测急性血流动力学CRT反应（AHR）。
根据Frank正交导联系统计算624份BV起搏心电图（25例LBBB患者，35种不同起搏配置）的VCG。测量正交导联（X、Y和Z）及三维投影中的最大QRS向量振幅（X、Y、Z和3D）和QRS面积（X、Y、Z和3D）。评估三维向量环的体积和体表心电图上的整体QRS时限（QRSD）。计算BV起搏与LBBB QRS波群之间VCG参数的差异（Δ）。dP/dt max增加10%被视为AHR。LBBB传导的特征是Z值较大（109μVs，四分位间距[IQR]：75；135），显著大于X值（22μVs，IQR：10；57）和Y值（44μVs，IQR：32；62，P<0.001）。总体而言，BV起搏时QRS时限、振幅和面积显著减小（P<0.001）。在所有VCG参数中，3D、Δ3D、Z、ΔZ、Δ3D和ΔQRSD可区分AHR反应与无反应（P<0.05）。ΔZ对阳性AHR的预测最佳（曲线下面积=0.813），优于任何其他VCG参数或QRSD测量值。
在所有VCG参数中，根据Frank Z导联计算的QRS面积减小对急性血流动力学反应的预测最佳。该方法可能是指导CRT植入和优化的一种简单、无创工具。
