Department of Cardiology, Westmead Hospital, Sydney, Australia.
Department of Cardiology, Westmead Applied Research Centre, University of Sydney, Sydney, New South Wales, Australia.
J Cardiovasc Electrophysiol. 2022 Jul;33(7):1494-1504. doi: 10.1111/jce.15487. Epub 2022 Apr 24.
Multielectrode mapping (MEM) and automated point collection are important enhancements to substrate mapping in ventricular tachycardia ablation. The effects of tissue contact and respiration on electrogram voltage with differing depolarization wavefronts with MEM catheters are unclear.
Bipolar and unipolar voltages were collected from control (n = 5) and infarcted (n = 7) animals with a multispline MEM catheter. Electro-anatomic maps were created in sinus rhythm, and right and left ventricular pacing. Analysis was performed across three collections: standard settings (SS), respiratory-phase gating (RG), and electrode-tissue proximity (TP). Comparison was made to scar detected by cardiac MRI (cMRI).
Compared to SS and RG acquisition, median bipolar and unipolar voltages were higher using TP, regardless of the depolarization wavefront. In infarct animals, bipolar voltages were 30.7%-50.5% higher for bipolar and 8.7%-13.8% higher on unipolar voltages with TP, compared to SS. The effect of RG on bipolar and unipolar voltages was minimal. Percentage of local abnormal ventricular activities was not impacted by acquisition settings or wavefront direction in infarct animals. Compared with cMRI defined scar, all three acquisition settings overestimated scar area using standard voltage-based cutoffs. RG improved the low voltage area concordance with MRI by 1.6%-5.1% whereas TP improved by 5.9%-8.4%.
High density voltage mapping with a MEM catheter is influenced by point collection settings. Tissue contact filters reduced low voltage areas and improved agreement with cMRI fibrosis in infarcted ovine hearts. These findings have critical implications for optimizing filter settings for high density substrate mapping in the left ventricle.
多电极标测（MEM）和自动点采集是室性心动过速消融中心律失常标测的重要增强手段。不同去极化波阵面下，MEM 导管的组织接触和呼吸对电图电压的影响尚不清楚。
使用多叶 MEM 导管从对照（n=5）和梗死（n=7）动物中采集双极和单极电压。在窦性节律、右心室和左心室起搏下创建电解剖图。在三个采集点进行分析：标准设置（SS）、呼吸相位门控（RG）和电极组织接近（TP）。与心脏 MRI（cMRI）检测到的瘢痕进行比较。
与 SS 和 RG 采集相比，使用 TP 时，无论去极化波阵面如何，双极和单极电压的中位数均较高。在梗死动物中，与 SS 相比，使用 TP 时，双极电压的双极和单极分别高出 30.7%-50.5%和 8.7%-13.8%。RG 对双极和单极电压的影响很小。在梗死动物中，采集设置或波阵面方向对局部异常心室活动的百分比没有影响。与 cMRI 定义的瘢痕相比，使用标准电压截断值，所有三种采集设置均高估了瘢痕面积。RG 提高了低电压区与 MRI 的一致性，提高了 1.6%-5.1%，而 TP 提高了 5.9%-8.4%。
MEM 导管的高密度电压标测受点采集设置的影响。组织接触滤波器减少了低电压区，并提高了与梗死羊心 cMRI 纤维化的一致性。这些发现对优化左心室高密度基质标测的滤波器设置具有重要意义。
