CHANGES IN CARDIAC REPOLARIZATION RESULTING FROM VENTRICULAR PACING

心室起搏引起的心脏复极变化

• 批准号: 7377987
• 负责人: WILLIAM LEWIS
• 金额: $ 0.11万
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-04-01 至 2007-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7377987
• 关键词: CHANGES; CARDIAC; REPOLARIZATION; RESULTING; VENTRICULAR

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The term "cardiac memory" has been used to describe changes that occur on the electrocardiogram after a change in the vector (or direction) of depolarization of the heart. For example, after a period of pacing the heart, the T wave will change its morphology or shape despite a return to the normal depolarization vector. This change will persist for many days. The T wave is representative of cardiac repolarization. Recently, changes in repolarization have been shown to be associated with increased mortality. Measures of repolarization have been developed which quantify these changes. The investigator hypothesizes that T wave changes induced by changes in the vector of depolarization induce repolarization abnormalities associated with increased risk. Patients with sinus node dysfunction traditionally receive dual chamber pacemakers and ventricular pacing is instituted as a matter of routine. Such patients do not need ventricular pacing and only require atrial pacing. Thus repolarization characteristics of a group of patients after atrial pacing as well as after ventricular pacing will be compared. The study design will be a double blinded, crossover trial. Patients with dual chamber pacemakers, implanted for sinus node dysfunction, will be evaluated for the ability to undergo atrial pacing safely. Patients with atrioventricular block are excluded. Assignment to an atrial pacing group or a dual chamber pacing group will be random. After greater than forty days of pacing in this mode, the patient will return and measurement of repolarization and depolarization will be made. All of these measurements will be done noninvasively. The patient's pacemaker will be reprogrammed to the alternative mode and the patient will return for repeat measurements after 40 additional days. Patients will be selected for the ability to be paced only from the atrium. Additionally, the ability to pace at normal rates from this chamber will be tested by pacing the heart at a relatively high rate and observing for AV block.

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子弹和调查员（PI）可能已经从其他NIH来源获得了主要资金，因此可以在其他清晰的条目中代表。列出的机构适用于该中心，这不一定是调查员的机构。术语“心脏记忆”已用于描述心脏去极化的向量（或方向）发生变化后心电图上发生的变化。例如，尽管恢复了正常的去极化载体，但在逐渐发出心脏之后，T波会改变其形态或形状。这种变化将持续很多天。 T波是心脏复极化的代表。最近，复极变化已证明与死亡率增加有关。已经开发了量化这些变化的复极度量。研究者假设，去极化载体的变化引起的T波变化会引起与风险增加有关的复极异常。传统上，鼻窦节点功能障碍的患者通常会接受双腔室动摇者，并根据常规疗法进行心室起搏。这样的患者不需要心室起搏，只需要心房起搏。因此，将比较一组患者心房起搏和心室起搏后的复极化特征。 研究设计将是一项双盲的跨界试验。将评估患有鼻窦节点功能障碍的双腔室起搏器的患者，以确保安全心房起搏的能力进行评估。排除心室障碍的患者被排除在外。分配到心房起搏组或双腔室起搏组将是随机的。在此模式下进行起搏的四十天以上，患者将返回并测量重极化和去极化。所有这些测量将无创进行。患者的起搏器将被重新编程为替代模式，并且患者将在40天后返回重复测量。将选择患者仅从中庭节奏的能力。此外，通过以相对较高的速率和观察AV块观察心脏来测试以正常速率步调的能力。