Department of Cardiology, Leiden University Medical Centre, Leiden, The Netherlands.
Department of Clinical Epidemiology, Leiden University Medical Centre, Leiden, The Netherlands.
Heart Rhythm. 2018 May;15(5):668-676. doi: 10.1016/j.hrthm.2018.01.013. Epub 2018 Jan 8.
Noninducibility of ventricular tachycardia (VT) with an equal or longer cycle length (CL) than that of the clinical VT is considered the minimum ablation endpoint in patients with structural heart disease. Because their clinical relevance remains unclear, fast nonclinical VTs are often not targeted. However, an accepted definition for fast VT is lacking. The shortest possible CL of a monomorphic reentrant VT is determined by the ventricular refractory period (VRP).
The purpose of this study was to propose a patient-specific definition for fast VT based on the individual VRP (fVT) and assess the prognostic significance of persistent inducibility after ablation of fVT for VT recurrence.
Of 191 patients with previous myocardial infarction or with nonischemic cardiomyopathy undergoing VT ablation, 70 (age 63 ± 13 years; 64% ischemic) remained inducible for a nonclinical VT and composed the study population. FVT was defined as any VT with CL ≤VRP + 30 ms. Patients were followed for VT recurrence.
After ablation, 30 patients (43%) remained inducible exclusively for fVT and 40 (57%) for any slower VT. Patients with only fVT had 3-year VT-free survival of 64% (95% confidence interval [CI] 46%-82%) compared to 27% (95% CI 14%-48%) for patients with any slower remaining VT (P = .013). Inducibility of only fVT was independently associated with lower VT recurrence (hazard ratio 0.38; 95% CI 0.19-0.86; P = .019). Among 36 patients inducible for any fVT, only 1 had recurrence with fVT.
In patients with structural heart disease, inducibility of exclusively fVT after ablation is associated with low VT recurrence.
在结构性心脏病患者中，诱发与临床室性心动过速（VT）等长或更长周期（CL）的 VT 不能诱导是消融的最低终点。由于其临床相关性尚不清楚，快速非临床性 VT 通常不是治疗靶点。然而，缺乏公认的快速 VT 定义。单相折返性 VT 的最短 CL 由心室不应期（VRP）决定。
本研究旨在提出一种基于个体 VRP（fVT）的快速 VT 患者特异性定义，并评估消融 fVT 后持续性可诱导性对 VT 复发的预测意义。
在 191 例既往心肌梗死或非缺血性心肌病患者中，70 例（年龄 63±13 岁；64%为缺血性）行 VT 消融术，仍可诱发出非临床性 VT，作为研究人群。fVT 定义为 CL≤VRP+30ms 的任何 VT。患者接受 VT 复发随访。
消融后，30 例（43%）患者仅对 fVT 具有可诱导性，40 例（57%）患者对任何较慢的 VT 具有可诱导性。仅 fVT 可诱导患者 3 年 VT 无复发生存率为 64%（95%置信区间 [CI] 46%-82%），而任何较慢的剩余 VT 患者为 27%（95% CI 14%-48%）（P=0.013）。仅 fVT 的可诱导性与较低的 VT 复发相关（风险比 0.38；95% CI 0.19-0.86；P=0.019）。在 36 例可诱发出任何 fVT 的患者中，仅有 1 例因 fVT 复发。
在结构性心脏病患者中，消融后仅 fVT 可诱导与 VT 复发率低相关。
