Predicting Blood Pressure in Patients Following Defibrillation in Patients With an ICD Implant
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 33
- 主要终点
- Correlation of sinus node cycle length to arterial baroreflex gain
研究概览
简要总结
During tachyarrhythmias, central venous pressures increases while arterial blood pressure (BP) decreases. The result is mixed messages to the central nervous system. On one hand, the unloading of the arterial baroreceptors results in reflex tachycardia and an increase in sympathetic nerve activity (SNA). On the other hand, the increase in filling pressure and thus the activation of the cardiopulmonary baroreceptors result in reflex bradycardia and sympathoinhibition. The investigators have previously shown that during supraventricular and ventricular tachycardia, arterial baroreflex gain (BRG) predominates with minimal contribution from the cardiopulmonary BRG. In addition, the investigators found that arterial BRG directly correlates with BP recovery following tachycardia termination. The roles of the arterial and cardiopulmonary BRGs during ventricular fibrillation (VF) however, remain unknown. Furthermore, the role of the arterial BRG in determining 1) BP recovery following VF induction and 2) the frequency of ventricular tachycardia (VT)/VF events in patients undergoing implantation of an implantable cardioverter/defibrillator (ICD) remain unknown. Analysis of the changes in sinus node cycle length during VF inductions in patients undergoing the implantation of a dual chamber or triple chamber ICD, provide a unique opportunity at looking at the autonomic changes that accompany VF.
详细描述
Design: This is a prospective, non-randomized study. The purpose of the present study is 1) to assess whether the changes in sinus node cycle length during VF induction following ICD implant correlate with arterial BRG, and 2) to determine whether these changes, and thus arterial BRG, predict BP recovery post-defibrillation.
POSSIBLE BENEFITS: There are no specific potential benefits for subjects participating in this study. Results from this study should greatly improve investigator's knowledge of VF and BP control.
POSSIBLE RISKS & DISCOMFORTS: The potential risks or discomforts are associated with the assessment of arterial baroreflex gain.
Nitroprusside (NTP) infusion may result in significant drop in blood pressure, heart attack, rhythm disturbances and stroke. The risks associated with phenylephrine (PE) infusion include blood pressure elevation, heart attack, rhythm disturbances and stroke. The likelihood of this is very small since the medications will be given in small, gradual doses with close monitoring by study personnel and physicians. If significant blood pressure changes occur, the medication will be stopped immediately. Stopping the medication will quickly reverse any blood pressure changes since the drugs have a very short half-life.
Study procedures: Arterial baroreflex gain measurements will be performed either at the patient's bedside or in the electrophysiology laboratory as described below. BP will be monitored using a non-invasive arterial tonometer (Colin, San Antonio, TX) if performed at bedside, or a preexisting arterial line if performed in the laboratory. Logistical considerations, such as timing, would be a reason for performing the assessment at the bedside. The majority of the studies will be performed in the laboratory. This procedure will take approximately 20 minutes.
研究设计
- 研究类型
- Observational
- 时间视角
- Prospective
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Indication for the implantation of an ICD with atrial lead placement
- •Presence of normal sinus rhythm
- •Age 18 or older
排除标准
- •Moderate to severe aortic stenosis
- •Embolic stroke within the last 6 months
结局指标
主要结局
Correlation of sinus node cycle length to arterial baroreflex gain
时间窗: up to 12 months
Assessment of whether changes in sinus node cycle length during ventricular fibrillation induction correlate with arterial baroreflex gain at scheduled and unscheduled implantable cardioverter/defibrillator related hospital visits for up to 12 months
次要结局
- Frequency of tachyarrhythmic events(6 months following ICD implant)
- Blood pressure recovery post-defibrillation(first 30 seconds after successful defibrillation)