背景:了解传导速度(CV)和电压幅度(VA)的动力学在心脏电生理学中至关重要,特别是针对慢速传导区和低电压区的基于基底的导管消融。这项研究利用超高密度映射来研究心率和起搏位置对波前方向变化的影响。CV,和健康猪心脏的VA。
方法:我们对四只健康幼猪进行了体内电生理研究,涉及各种起搏位置和心率。在固有正常窦性心律(NSR)和电起搏期间进行高分辨率电解剖标测。该研究包括三个层面的详细分析:整个心脏腔,分区域,和局部5毫米直径的圆形区域。采用线性混合效应模型分析心率和起搏位置对不同区域CV和VA的影响。
结果:心率的增加与传导速度的增加和电压幅度的降低相关。起搏影响传导速度和电压振幅。起搏也影响传导速度和电压振幅,根据不同心腔内的起搏位置观察到不同的效果。右心房(RA)起搏可降低所有心脏腔的CV。整个心脏腔中的总体CV和VA变化并未在所有子区域中得到统一反映,而次区域CV和VA变化并不总是反映在总体分析中。总的来说,起搏引起的绝对CV和VA变化存在显著差异.
结论:心率和起搏位置影响健康幼猪心脏的CV和VA。子区域分析表明,心脏腔的特定区域更容易起搏。高分辨率制图有助于检测区域变化,强调CV和VA的实质性生理变化。
BACKGROUND: Understanding the dynamics of conduction velocity (CV) and voltage amplitude (VA) is crucial in cardiac electrophysiology, particularly for substrate-based catheter ablations targeting slow conduction zones and low voltage areas. This study utilizes ultra-high-density mapping to investigate the impact of heart rate and pacing location on changes in the wavefront direction, CV, and VA of healthy pig hearts.
METHODS: We conducted in vivo electrophysiological studies on four healthy juvenile pigs, involving various pacing locations and heart rates. High-resolution electroanatomic mapping was performed during intrinsic normal sinus rhythm (NSR) and electrical pacing. The study encompassed detailed analyses at three levels: entire heart cavities, subregions, and localized 5-mm-diameter circular areas. Linear mixed-effects models were used to analyze the influence of heart rate and pacing location on CV and VA in different regions.
RESULTS: An increase in heart rate correlated with an increase in conduction velocity and a decrease in voltage amplitude. Pacing influenced conduction velocity and voltage amplitude. Pacing also influenced conduction velocity and voltage amplitude, with varying effects observed based on the pacing location within different heart cavities. Pacing from the right atrium (RA) decreased CV in all heart cavities. The overall CV and VA changes in the whole heart cavities were not uniformly reflected in all subregions and subregional CV and VA changes were not always reflected in the overall analysis. Overall, there was a notable variability in absolute CV and VA changes attributed to pacing.
CONCLUSIONS: Heart rate and pacing location influence CV and VA within healthy juvenile pig hearts. Subregion analysis suggests that specific regions of the heart cavities are more susceptible to pacing. High-resolution mapping aids in detecting regional changes, emphasizing the substantial physiological variations in CV and VA.