Qingguo Meng1, Sijia Wang1, Sijing Yan2, Yun Xu1, Zhixia Wu3, Jie Zhou3, Zhiyu Guo4, Lixue Yin1, Yan Deng1, Tianhang Feng4. 1. Key Laboratory of Ultrasound in Cardiac Electrophysiology and Biomechanics of Sichuan Province, Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu, China. 2. Chongqing City Hospital of Traditional Chinese Medicine, Chongqing, China. 3. Zunyi Medical University, Zunyi, China. 4. Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital, Chengdu, China.
Abstract
PURPOSE: We set out to undertake a preliminary assessment of the left ventricular hemodynamic status with right ventricular double-chamber pacing by energy loss (EL), wall shear stress (WSS), and circulation intensity (CIR) of vector flow mapping (VFM). We also planned to evaluate the value of VFM technology by measuring cardiac function after pacemaker implantation. METHOD: Data from 58 patients living with right ventricular double-chamber (right ventricular septal) pacemakers as well as 58 healthy volunteers matched in age and gender were collected. The EL, numbers of vortex cycles (n), area (A), CIR, and WSS of the left ventricle with different phases of the same cardiac cycle were obtained. RESULTS: The EL of the left ventricle was significantly higher in the pacemaker group than the control group at partial section of atrial contraction (AC), isovolumetric contraction (IVC), and rapid ejection (RE) (P < 0.05). The WSS of the left ventricle was significantly lower in the pacemaker group than the control group at part of the section in the rapid filling (RF), the AC, IVC, and RE phase (P < 0.05). DISCUSSION: EL in the left ventricular was significantly increased, while related WSS was significantly decreased in patients with right ventricular double-chamber pacing. Our exploration of the state of the flow field in the left ventricular cavity revealed that the implantation of the right ventricular double-chamber pacemaker led to an abnormal left ventricular hemodynamic state, reducing the left ventricular systolic efficiency.
PURPOSE: We set out to undertake a preliminary assessment of the left ventricular hemodynamic status with right ventricular double-chamber pacing by energy loss (EL), wall shear stress (WSS), and circulation intensity (CIR) of vector flow mapping (VFM). We also planned to evaluate the value of VFM technology by measuring cardiac function after pacemaker implantation. METHOD: Data from 58 patients living with right ventricular double-chamber (right ventricular septal) pacemakers as well as 58 healthy volunteers matched in age and gender were collected. The EL, numbers of vortex cycles (n), area (A), CIR, and WSS of the left ventricle with different phases of the same cardiac cycle were obtained. RESULTS: The EL of the left ventricle was significantly higher in the pacemaker group than the control group at partial section of atrial contraction (AC), isovolumetric contraction (IVC), and rapid ejection (RE) (P < 0.05). The WSS of the left ventricle was significantly lower in the pacemaker group than the control group at part of the section in the rapid filling (RF), the AC, IVC, and RE phase (P < 0.05). DISCUSSION: EL in the left ventricular was significantly increased, while related WSS was significantly decreased in patients with right ventricular double-chamber pacing. Our exploration of the state of the flow field in the left ventricular cavity revealed that the implantation of the right ventricular double-chamber pacemaker led to an abnormal left ventricular hemodynamic state, reducing the left ventricular systolic efficiency.