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P365 The study of atrial electrical remodeling in elderly heart failure patients
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Posters / International Journal of Cardiology 125 Suppl. 1 (2008) S51–S73
left ventricular end-systolic volume (LVESV) were measured with biplane Simpson, and ejection fraction (EF) and cardiac output (CO) were calculated. Pathohistological and ultrastructural changes were tested by light microscope and transmission electron microscope. Results: There were no changes of cardiac characteristics before and after the procedure in sham-operated group. In the ventricular pacing group, after 6 weeks rapid ventricular pacing, compared to the sham-operated group, LAESV was significantly increased (23.2±4.1 vs 13.5±1.9 cm3 , P < 0.01), LVEDV was significantly increased (56.2±11.3 vs 33.7±9.6 cm3 , P < 0.01), LVESV was significantly increased (38.4±8.4 vs 14.5±8.6 cm3 , P < 0.01), EF was significantly decreased (31.4±10.2% vs 56.8±4.5%, P < 0.01) and CO was significantly decreased (1.2±0.5 vs 2.8±1.6 L/min, P < 0.01). The characteristic pathological changes were found in ventricular pacing group, such as atrial myocardial cell degeneration, muscle fibronolysis, mitochondria swelling and numerous mesenchymal collagen edema. Conclusion: Atrial structural remodeling may play an important role in the formation of atrial fibrillation in congestive heart failure. Supported by a grant from Young Foundation of Health Department in HeiLongJiang Province (No. 2005-187). P365 The study of atrial electrical remodeling in elderly heart failure patients J.Y. Xue1 *, G.Q. Du2 , S.S. Yang1 , Y. Li1 , H.Y. Gu1 , W.M. Li1 . of Cardiology, The First Clinical College, Harbin Medical University, Harbin 150001, China, 2 Department of Ultrasound, The Second Clinical College, Harbin Medical University, Harbin 150086, China 1 Department
Objective: To observe the atrial electrophysiological characteristics of elderly heart failure patients (age 60) and investigate the mechanism of atrial fibrillation (AF) in heart failure. Methods: Forty-one patients with paroxysmal supraventricular tachycardia undergoing radiofrequency catheter ablation were divided into heart failure group (17 patients, NYHA II−III grade, left ventricular ejection fraction, LVEF 45%) and control group (24 patients, LVEF 60%). Before radiofrequency catheter ablation every patient was measured systolic dimension of left atrial by echocardiography through thorax. After successful radiofrequency catheter ablation, we measured atrial effective refrectory period (AERP) in multiple sites including high right atrium (HRA), low right atrium (LRA) and his bundle area (HIS). AERP dispersion (AERPd) and inter-atrium, intra-atrium conduction time were measured. The maximum P wave duration (Pmax), minimum P wave duration (Pmin) and P wave dispersion (Pd) were measured from the 12-lead surface electrocardiogram of all patients. The information of induced atrial fibrillation were recorded. Results: (1) Compared with control group, the systolic dimension of left atrial and inducing rate of AF were enlarged significantly (P < 0.05) and frequency and dutation of AF significantly increased (P < 0.01) in the heart failure group. (2) In the heart failure group, compared with control group, AERP prolonged slightly, AERPd increased significantly (61.4±20.6 ms vs. 40.6±15.2 ms, P < 0.05), inter-atrium conduction time (53.9±14.7 ms vs. 37.3±12.9 ms, P < 0.05), and intraatrium conduction time (61.6±18.2 ms vs. 41.8±17.5 ms, P < 0.05), prolonged significantly. (3) Pmax and Pd were found to be significantly higher in the heart failure group than those in the control group (Pmax: 147.8±26.3 ms vs. 116.2±12.5 ms, P < 0.05; Pd: 71.7±11.6 ms vs. 36.4±7.6 ms, P < 0.01). Conclusion: Inter-atrium and intra-atrium conduction abnormalities and increased AERPd may play an important role in the electrophysiologic substrate for AF in elderly heart failure patients.
P366 Measurement of left ventricular twisting with premature ventricular contraction from right ventricle by velocity vector imaging J. Yao *, D. Xu, F.X. Lu, Y.H. Yong, L. Ji, C.H. Zhou. Department of Cardiology, First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China Objective: To assess left ventricular (LV) twisting parameters with healthy subjects and premature ventricular contraction (PVC) bigeminy from right ventricle (RV) patients in different layers, and demonstrate the rules of LV myocardium dynamics in sinus rhythm and PVC from RV. Methods: Ten patients with PVC bigeminy from RV and twelve healthy subjects underwent the examination of two-dimensional ultrasound, then the standard LV mitral valve (MV) and apical shortaxis views were acquired. The twisting angle (TA) and untwisting time (UT) were measured. Results: In healthy subjects myocardium of LV MV short-axis twisted in clockwise, that of LV apical short-axis twisted in counter-clockwise. TA of endocardium was higher than that of epicardium (P < 0.01). In sinus contraction of PVC bigeminy from RA patients, TA was lower than that of healthy subjects both in MV and apical short-axis respectively (P < 0.05), and UT was shorter than later (P < 0.05). In PVC the TA curve is bidirectional, and in early systolic TA twisted reversely compared with that of healthy subjects and sinus contraction of PVC. Conclusions: Twisting parameters could be used to assess myocardium dynamics during different ventricular mechanical activation. VVI were novel indices to analyse myocardium twisting. P367 Molecular mechanisms of felodipine suppressing atherosclerosis in high cholesterol-diet apolipoprotein E knock-out mice R. Yao *, X. Cheng, Y.H. Liao, Y. Chen, J.J. Xie, X. Yu, Y.J. Ding, T.T. Tang. Laboratory of Cardiovascular Immunology, Institute of Cardiology, Union Hospital, Tongji Medical College of Huazhong University of Science and Technology, Wuhan 430022, China Objectives: Oxidative stress and inflammation processes are key components of atherosclerosis, from fatty streak formation to plaque rupture and thrombosis. Evidence has revealed that calcium channel blockers (CCBs) could retard atherogenesis, but the exact mechanisms have not been fully elucidated. The present study was undertaken to investigate the potential effects and molecular mechanisms of a calcium channel blocker felodipine on the process of atherosclerosis in high cholesterol-diet (HCD) apolipoprotein E knock-out (ApoE KO) mice. Methods: Adult male ApoE KO mice were given normal diet (ND) or HCD and randomized to no treatment or felodipine 5 mg/kg/d for 12 weeks. Systolic blood pressure was measured by a kind of noninvasive tail cuff system in conscious mice. The lipid concentration was measured by autoanalyzer. Atherosclerotic lesion area in arotic root was evaluated by oil red O staining. NADPH oxidase subunits and inflammatory cytokines were measured by real-time reversetranscription polymerase chain reaction (PCR) and western blot. Results: The ApoE KO mice with HCD were associated with a marked increase in plasma lipid levels, atherosclerotic lesion area, as well as the expressions of NADPH oxidase subunits (p47phox and Rac-1), nuclear factor-úB (NF-úB) in nucleus, phosphor-inhibitors of úB (p-IúB), tumor necrosis factor-a (TNF-a), monocyte chemoattractant protein-1 (MCP-1) and vascular cell adhesion molecule-1 (VCAM-1). These changes were suppressed in mice which were treated with felodipine 5 mg/kg/d for 12 weeks concomitant with HCD administration, with no significant change in systolic blood pressure and plasma lipid levels. Conclusions: The results suggest that felodipine can attenuate atherosclerosis, and this effect is in part related to inhibition of oxidative stress and inflammatory signal transduction pathways which leads to the decrease in the expression of inflammatory cytokines.
Posters / International Journal of Cardiology 125 Suppl. 1 (2008) S51–S73
left ventricular end-systolic volume (LVESV) were measured with biplane Simpson, and ejection fraction (EF) and cardiac output (CO) were calculated. Pathohistological and ultrastructural changes were tested by light microscope and transmission electron microscope. Results: There were no changes of cardiac characteristics before and after the procedure in sham-operated group. In the ventricular pacing group, after 6 weeks rapid ventricular pacing, compared to the sham-operated group, LAESV was significantly increased (23.2±4.1 vs 13.5±1.9 cm3 , P < 0.01), LVEDV was significantly increased (56.2±11.3 vs 33.7±9.6 cm3 , P < 0.01), LVESV was significantly increased (38.4±8.4 vs 14.5±8.6 cm3 , P < 0.01), EF was significantly decreased (31.4±10.2% vs 56.8±4.5%, P < 0.01) and CO was significantly decreased (1.2±0.5 vs 2.8±1.6 L/min, P < 0.01). The characteristic pathological changes were found in ventricular pacing group, such as atrial myocardial cell degeneration, muscle fibronolysis, mitochondria swelling and numerous mesenchymal collagen edema. Conclusion: Atrial structural remodeling may play an important role in the formation of atrial fibrillation in congestive heart failure. Supported by a grant from Young Foundation of Health Department in HeiLongJiang Province (No. 2005-187). P365 The study of atrial electrical remodeling in elderly heart failure patients J.Y. Xue1 *, G.Q. Du2 , S.S. Yang1 , Y. Li1 , H.Y. Gu1 , W.M. Li1 . of Cardiology, The First Clinical College, Harbin Medical University, Harbin 150001, China, 2 Department of Ultrasound, The Second Clinical College, Harbin Medical University, Harbin 150086, China 1 Department
Objective: To observe the atrial electrophysiological characteristics of elderly heart failure patients (age 60) and investigate the mechanism of atrial fibrillation (AF) in heart failure. Methods: Forty-one patients with paroxysmal supraventricular tachycardia undergoing radiofrequency catheter ablation were divided into heart failure group (17 patients, NYHA II−III grade, left ventricular ejection fraction, LVEF 45%) and control group (24 patients, LVEF 60%). Before radiofrequency catheter ablation every patient was measured systolic dimension of left atrial by echocardiography through thorax. After successful radiofrequency catheter ablation, we measured atrial effective refrectory period (AERP) in multiple sites including high right atrium (HRA), low right atrium (LRA) and his bundle area (HIS). AERP dispersion (AERPd) and inter-atrium, intra-atrium conduction time were measured. The maximum P wave duration (Pmax), minimum P wave duration (Pmin) and P wave dispersion (Pd) were measured from the 12-lead surface electrocardiogram of all patients. The information of induced atrial fibrillation were recorded. Results: (1) Compared with control group, the systolic dimension of left atrial and inducing rate of AF were enlarged significantly (P < 0.05) and frequency and dutation of AF significantly increased (P < 0.01) in the heart failure group. (2) In the heart failure group, compared with control group, AERP prolonged slightly, AERPd increased significantly (61.4±20.6 ms vs. 40.6±15.2 ms, P < 0.05), inter-atrium conduction time (53.9±14.7 ms vs. 37.3±12.9 ms, P < 0.05), and intraatrium conduction time (61.6±18.2 ms vs. 41.8±17.5 ms, P < 0.05), prolonged significantly. (3) Pmax and Pd were found to be significantly higher in the heart failure group than those in the control group (Pmax: 147.8±26.3 ms vs. 116.2±12.5 ms, P < 0.05; Pd: 71.7±11.6 ms vs. 36.4±7.6 ms, P < 0.01). Conclusion: Inter-atrium and intra-atrium conduction abnormalities and increased AERPd may play an important role in the electrophysiologic substrate for AF in elderly heart failure patients.
P366 Measurement of left ventricular twisting with premature ventricular contraction from right ventricle by velocity vector imaging J. Yao *, D. Xu, F.X. Lu, Y.H. Yong, L. Ji, C.H. Zhou. Department of Cardiology, First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China Objective: To assess left ventricular (LV) twisting parameters with healthy subjects and premature ventricular contraction (PVC) bigeminy from right ventricle (RV) patients in different layers, and demonstrate the rules of LV myocardium dynamics in sinus rhythm and PVC from RV. Methods: Ten patients with PVC bigeminy from RV and twelve healthy subjects underwent the examination of two-dimensional ultrasound, then the standard LV mitral valve (MV) and apical shortaxis views were acquired. The twisting angle (TA) and untwisting time (UT) were measured. Results: In healthy subjects myocardium of LV MV short-axis twisted in clockwise, that of LV apical short-axis twisted in counter-clockwise. TA of endocardium was higher than that of epicardium (P < 0.01). In sinus contraction of PVC bigeminy from RA patients, TA was lower than that of healthy subjects both in MV and apical short-axis respectively (P < 0.05), and UT was shorter than later (P < 0.05). In PVC the TA curve is bidirectional, and in early systolic TA twisted reversely compared with that of healthy subjects and sinus contraction of PVC. Conclusions: Twisting parameters could be used to assess myocardium dynamics during different ventricular mechanical activation. VVI were novel indices to analyse myocardium twisting. P367 Molecular mechanisms of felodipine suppressing atherosclerosis in high cholesterol-diet apolipoprotein E knock-out mice R. Yao *, X. Cheng, Y.H. Liao, Y. Chen, J.J. Xie, X. Yu, Y.J. Ding, T.T. Tang. Laboratory of Cardiovascular Immunology, Institute of Cardiology, Union Hospital, Tongji Medical College of Huazhong University of Science and Technology, Wuhan 430022, China Objectives: Oxidative stress and inflammation processes are key components of atherosclerosis, from fatty streak formation to plaque rupture and thrombosis. Evidence has revealed that calcium channel blockers (CCBs) could retard atherogenesis, but the exact mechanisms have not been fully elucidated. The present study was undertaken to investigate the potential effects and molecular mechanisms of a calcium channel blocker felodipine on the process of atherosclerosis in high cholesterol-diet (HCD) apolipoprotein E knock-out (ApoE KO) mice. Methods: Adult male ApoE KO mice were given normal diet (ND) or HCD and randomized to no treatment or felodipine 5 mg/kg/d for 12 weeks. Systolic blood pressure was measured by a kind of noninvasive tail cuff system in conscious mice. The lipid concentration was measured by autoanalyzer. Atherosclerotic lesion area in arotic root was evaluated by oil red O staining. NADPH oxidase subunits and inflammatory cytokines were measured by real-time reversetranscription polymerase chain reaction (PCR) and western blot. Results: The ApoE KO mice with HCD were associated with a marked increase in plasma lipid levels, atherosclerotic lesion area, as well as the expressions of NADPH oxidase subunits (p47phox and Rac-1), nuclear factor-úB (NF-úB) in nucleus, phosphor-inhibitors of úB (p-IúB), tumor necrosis factor-a (TNF-a), monocyte chemoattractant protein-1 (MCP-1) and vascular cell adhesion molecule-1 (VCAM-1). These changes were suppressed in mice which were treated with felodipine 5 mg/kg/d for 12 weeks concomitant with HCD administration, with no significant change in systolic blood pressure and plasma lipid levels. Conclusions: The results suggest that felodipine can attenuate atherosclerosis, and this effect is in part related to inhibition of oxidative stress and inflammatory signal transduction pathways which leads to the decrease in the expression of inflammatory cytokines.