Feasibility and Safety of Transthoracic Echocardiography-Guided Permanent Pacemaker Implantation Without Fluoroscopy
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 31
- 试验地点
- 1
- 主要终点
- Procedural Feasibility and Success Rate
研究概览
简要总结
Permanent pacemaker implantation is traditionally performed under fluoroscopic (X-ray) guidance. Although effective, fluoroscopy exposes patients and medical staff to ionizing radiation. Transthoracic echocardiography (TTE) is a non-invasive ultrasound imaging technique that allows real-time visualization of cardiac structures without radiation exposure. However, its role in guiding permanent pacemaker implantation has not been systematically evaluated.
This study aims to assess the feasibility and safety of performing permanent pacemaker implantation under sole TTE guidance. In the first phase, eligible patients will undergo pacemaker implantation guided only by transthoracic echocardiography. In the second phase, outcomes of patients treated with TTE guidance will be compared with matched patients undergoing conventional fluoroscopy-guided implantation. The study will evaluate procedural success, lead positioning accuracy, electrical performance, complication rates, and elimination of radiation exposure. The overall goal is to determine whether a radiation-free imaging strategy can safely replace conventional fluoroscopic guidance in selected patients requiring pacemaker implantation.
详细描述
Fluoroscopy-guided permanent pacemaker implantation has been the standard imaging strategy for decades. While fluoroscopy provides reliable projection-based visualization of lead advancement, it exposes patients and medical personnel to ionizing radiation and does not allow direct visualization of myocardial tissue contact or early structural complications. Increasing awareness of cumulative radiation exposure has led to the exploration of alternative imaging strategies in structural and electrophysiological interventions.
Transthoracic echocardiography (TTE) provides real-time, radiation-free visualization of cardiac chambers, septal structures, valvular anatomy, and the pericardial space. TTE has been successfully applied in selected structural heart procedures; however, its use in guiding permanent pacemaker implantation has not been systematically studied. The principal challenges of TTE-guided pacing include limited visualization of the entire lead shaft, difficulty in assessing three-dimensional orientation, and uncertainty regarding fixation mechanics. With procedural refinements and structured imaging protocols, these limitations may be overcome.
This study is designed to evaluate a radiation-free implantation strategy using sole transthoracic echocardiographic guidance. The first component prospectively assesses procedural feasibility and safety in consecutively enrolled patients. The second component compares outcomes of the TTE-guided cohort with a matched cohort undergoing conventional fluoroscopy-guided implantation. The same prospectively enrolled TTE cohort will serve both feasibility assessment and comparative analysis.
The central hypothesis is that TTE-guided pacemaker implantation can achieve high procedural success and acceptable electrical performance while eliminating radiation exposure and maintaining safety comparable to conventional fluoroscopic guidance. By leveraging direct septal visualization and continuous structural monitoring, this approach may provide mechanistic advantages in lead positioning accuracy and complication detection.
If validated, this strategy could represent an important step toward fully radiation-free electrophysiological and structural cardiac interventions.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Treatment
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 80 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Age ≥ 18 years
- •Indication for permanent pacemaker implantation according to current ESC or ACC/AHA guidelines
- •Adequate transthoracic echocardiographic acoustic window allowing visualization of right atrium, right ventricle, and interventricular septum
- •Ability to provide written informed consent
排除标准
- •Inadequate transthoracic acoustic window precluding reliable visualization of right-sided cardiac structures
- •Severe tricuspid regurgitation (moderate-to-severe or greater)
- •Left ventricular ejection fraction <35% without indication for cardiac resynchronization therapy
- •Documented malignant ventricular arrhythmia requiring implantable cardioverter-defibrillator as primary indication
- •Intrinsic heart rate <40 beats per minute with hemodynamic instability requiring emergent pacing
- •Active systemic infection
- •Life expectancy less than 12 months due to non-cardiac comorbidities
研究组 & 干预措施
TTE-guided arm
Transthoracic Echocardiography-Guided Pacemaker Implantation
干预措施: Permanent Pacemaker Implantation (Procedure)
结局指标
主要结局
Procedural Feasibility and Success Rate
时间窗: From initiation of vascular access to hospital discharge, assessed up to 5 days after the index procedure.
Feasibility phase: Successful completion of permanent pacemaker implantation under sole transthoracic echocardiographic (TTE) guidance without fluoroscopic conversion and with acceptable acute electrical parameters (capture threshold ≤1.5 V at 0.4 ms, stable sensing amplitude, and lead impedance within manufacturer-recommended range). Comparative phase: Successful device implantation without major procedural complications and with acceptable acute electrical parameters.
次要结局
- Electrical Stability at 3 Months(Assessed at 3 months (±14 days) after implantation.)
- Total Procedure Time(During the index procedure (single-day assessment at Day 0).)
- Lead Positioning Time(During the index procedure (single-day assessment at Day 0).)
- Radiation Exposure(During the index procedure (single-day assessment at Day 0).)
- Acute Electrical Performance(Immediately post-implantation (Day 0, within 24 hours after device placement).)
- Major Procedural Complications(From the date of the index procedure until the first occurrence of a major procedural complication or completion of 12-month follow-up, whichever occurs first.)
- Structural Cardiac Impact(Assessed at discharge (≤5 days), 3 months (±14 days), 6 months (±30 days), and 12 months (±30 days) after implantation.)
研究者
Pan Xiangbin
Prof.
Chinese Academy of Medical Sciences, Fuwai Hospital