O'Neill James, Hogarth Andrew J, Pearson Ian, Law Hannah, Bowes Robert, Kidambi Ananth, Wheatcroft Stephen, Sivananthan U Mohanaraj, Tayebjee Muzahir H
Department of Cardiology, Leeds Teaching Hospitals NHS Trust, Leeds General Infirmary, Great George Street, Leeds, LS1 3EX, United Kingdom.
Catheter Cardiovasc Interv. 2018 Aug 1;92(2):269-273. doi: 10.1002/ccd.27349. Epub 2017 Oct 16.
The assessment of myocardial viability is crucial before percutaneous coronary intervention (PCI) is carried out to ensure that the patient will gain benefit. Trans-coronary pacing (TCP) has previously been used to pace myocardium but may also provide information on myocardial viability.
Patients with a single, significant coronary stenosis requiring PCI were recruited. They underwent a cardiac MRI to assess myocardial viability. Prior to PCI, a coronary guidewire was used to measure pacing threshold, impedance, and R-wave amplitude in different myocardial segments to determine any association between the electrical parameters and myocardial viability.
Eight patients were recruited and six patients underwent intervention. Pacing sensitivity did not demonstrate statistically significant differences between normal and scarred myocardium. Impedance demonstrated a mean of 304.8 ± 74.0 Ω in normal myocardium (NM), 244.1 ± 66.6 Ω in <50% myocardial scar (MS), and 222.3 ± 33.8 Ω in ≥50% MS. Pacing threshold demonstrated a mean of 1.960 ± 1.226 V in NM, 5.009 ± 2.773 V in <50% MS, and 3.950 ± 0.883 V in ≥50% MS. For both impedance and threshold, there was a significant difference among the groups (P = 0.12 and P = 0.002, respectively), and post hoc Tukey's pairwise comparison demonstrated significant differences between NM and scarred myocardium. No significant differences were found between <50% MS and ≥50% MS.
Impedance and pacing threshold, measured during TCP, can be used to differentiate between normal myocardium and scarred myocardium. Further research is needed to determine whether TCP can discriminate between viable and nonviable myocardium.
在进行经皮冠状动脉介入治疗（PCI）之前，评估心肌存活性至关重要，以确保患者能够获益。经冠状动脉起搏（TCP）此前已用于心肌起搏，但也可能提供有关心肌存活性的信息。
招募了患有单一严重冠状动脉狭窄且需要进行PCI的患者。他们接受了心脏磁共振成像以评估心肌存活性。在PCI之前，使用冠状动脉导丝测量不同心肌节段的起搏阈值、阻抗和R波振幅，以确定电参数与心肌存活性之间的任何关联。
招募了8名患者，其中6名患者接受了干预。正常心肌和瘢痕心肌之间的起搏敏感性没有显示出统计学上的显著差异。正常心肌（NM）的阻抗平均值为304.8±74.0Ω，<50%心肌瘢痕（MS）的阻抗平均值为244.1±66.6Ω，≥50% MS的阻抗平均值为222.3±33.8Ω。NM的起搏阈值平均值为1.960±1.226V，<50% MS的起搏阈值平均值为5.009±2.773V，≥50% MS的起搏阈值平均值为3.950±0.883V。对于阻抗和阈值，各组之间均存在显著差异（分别为P = 0.12和P = 0.002），事后Tukey成对比较显示NM与瘢痕心肌之间存在显著差异。<50% MS和≥50% MS之间未发现显著差异。
TCP期间测量的阻抗和起搏阈值可用于区分正常心肌和瘢痕心肌。需要进一步研究以确定TCP是否能够区分存活心肌和无存活心肌。
