目前转换波AVO(Amplitude Versus Offset)反演或纵波、转换波联合AVO反演是基于Aki等的反射系数近似公式,通常反演结果为上、下层速度比值和速度平均比值.本文在Shuey和郑晓东近似公式的基础上,运用最小平方算法,提出一种P-P波和P-SV波...目前转换波AVO(Amplitude Versus Offset)反演或纵波、转换波联合AVO反演是基于Aki等的反射系数近似公式,通常反演结果为上、下层速度比值和速度平均比值.本文在Shuey和郑晓东近似公式的基础上,运用最小平方算法,提出一种P-P波和P-SV波联合AVO反演下层介质纵、横波速度及泊松比的方案,并应用于双层含气砂岩模型上,误差在10%以内.此方案要求上、下层物性差别不大且入射角小于30°,但不需要速度比值为常数2的假设.展开更多
BACKGROUND： Activation of the sympathetic nervous system plays an important role in regulating cardiovascular actions. P wave parameters can provide general information on central cardiovascular autonomic regulatory ...BACKGROUND： Activation of the sympathetic nervous system plays an important role in regulating cardiovascular actions. P wave parameters can provide general information on central cardiovascular autonomic regulatory responses, which are altered in patients with anxiety disorders and depression. In particular, there are no reports addressing changes in P wave duration and dispersion. OBJECTIVE： To compare the differences in P wave duration and P wave dispersion between patients with anxiety disorders and depression, because patients with anxiety disorders and depression develop abnormal electrocardiograms. DESIGN, TIME AND SETTING： A non-randomized concurrent controlled study was performed. Patients with depression and general anxiety disorders were admitted at the psychiatry outpatient clinics of the Medical Faculty of Duezce University of Turkey between May 2005 and October 2006. PARTICIPANTS： A total of 71 consecutive patients with depression and anxiety disorders, as well as 50 physically and mentally healthy age- and gender-matched controls were selected. METHODS： Electrocardiogram records were obtained at the time of admission to the outpatient clinics. MAIN OUTCOME MEASURES： P wave duration and P wave dispersion were measured. RESULTS： Both the maximum （Prnax） and minimum （Pmin） P wave duration were greater in patients with psychiatric disorders than in healthy controls. Pmax was significantly greater in patients with depression or anxiety disorders （Bonferroni test, P 〈 0.017）. The P wave dispersion was similar between patients and controls （P 〉 0.017）. P waves were similar between panic patients and other anxiety patients. Beck depression results were positively correlated with Prawn and Prnax （r= 0.374, 0.302, P = 0.013, 0.049, respectively）, and not associated with P wave dispersion （P 〉 0.05）. CONCLUSION： Psychiatric disorders are associated with increases in Prnax, but not with P wave dispersion. The P wave changes were associated with the degree of depression.展开更多
Objective: The aim of the study was to investigate the impact of P-maximum and P-wave dispersion on the long term clinical outcome after successful percutaneous balloon mitral valvuloplasty (PBMV) in patients with mit...Objective: The aim of the study was to investigate the impact of P-maximum and P-wave dispersion on the long term clinical outcome after successful percutaneous balloon mitral valvuloplasty (PBMV) in patients with mitral stenosis (MS) and sinus rhythm. Also to test the correlation between P-variables and right ventricular function and pulmonary artery pressure before and after PMBV. Methods: Eighty-five patients undergoing PMBV were enrolled in this study. We evaluated P-maximum, P-minimum and P-wave dispersion before and one month after PBMV. We studied the changes in pulmonary arterial pressure (PAP), left atrial (LA) dimension, mitral diastolic gradient, and mitral valve area, in addition to the changes in right ventricular function utilizing tissue Doppler assessment both before and after PMBV, in addition the role of the P-wave dispersion in predicttion of late cardiac events. Results: There were significant decreases in mean diastolic gradient, PAP, and LA size and significant improvement in right ventricular tissue Doppler indices after PMBV. Ac- company these hemodynamic changes after PMBV. P-maximum and P-wave dispersion were found to be decreased (P < 0.001). Patients developed cardiac events during follow-up had a higher P-maximum and P-dispersion than those without late cardiac events (P < 0.001). Moreover the changes in P-maxi- mum and P-dispersion before and after PMBV in patients with cardiac events were not significant, while P-maximum and P-dispersion significantly (P < 0.002) decreased in patients without events It was revealed with linear regression and correlation analy- sis that the degree of and the changes in P-maximum and P-wave dispersion were correlated with devel- opment of late cardiac events after PMBV, with Cut-off values of ≥62.8 msec for P-wave dispersion and 118 mes for P-maximum.ROC curve showed AUC of 0.919 for P-wave dispersion and 0.913 for P-maximum (P < 0.001). Conclusion: P-wave maximum and dispersion are significantly increased in patients with mitral stenosis. These changes decreased significantly after PMBV. The P-maximum and P-wave dispersion changes were correlated with significant impairment of right dysfunction and the degree of pulmonary artery pressure. P-maximum and P-wave dispersion could be considered as independent predictors of late outcome of patients with MS after successful PMBV (AF, recurrent hospital admission, embolic phenomenon deterioration of right ventricular function).展开更多
目的:探讨持续性心房颤动(房颤)导管射频消融术后P波时限及离散度与术后早期与晚期复发房颤的关系。方法:连续入选80例首次行导管射频消融术的持续性房颤患者,其中男性46例,女性34例,平均年龄(60.6±8.1)岁,平均随访(9.3±2.9)...目的:探讨持续性心房颤动(房颤)导管射频消融术后P波时限及离散度与术后早期与晚期复发房颤的关系。方法:连续入选80例首次行导管射频消融术的持续性房颤患者,其中男性46例,女性34例,平均年龄(60.6±8.1)岁,平均随访(9.3±2.9)个月。根据3个月之内(早期)和之外(晚期)复发房颤情况,分为两个对比组:早期复发组和早期未复发组;晚期复发组和晚期未复发组。所有患者术后24 h内均记录12导联心电图,并测量P波时限,计算出最长P波时限(Pmax),最短P波时限(Pmin),以及两值之差即P波离散度(Pd),分析P波时限及离散度与术后早期与晚期复发房颤的关系。结果:17例患者早期复发房颤,与早期未复发组患者比较,Pd明显增长[(74.35±17.78) ms vs (60.73±18.37) ms,P=0.008];12例早期复发患者(70.6%)出现延迟恢复,未发现早期复发为晚期复发预测因子。14例患者晚期复发房颤,与晚期未复发组患者相比,Pd明显增长[(75.71±16.49)ms vs (61.06±18.59) ms,P=0.008]。通过观察不同临界值,发现Pd≥60 ms对预测术后晚期复发房颤有一定价值,敏感度85%、特异度50%、阳性预测值26.7%、阴性预测值94.3%。结论:Pd与持续性房颤导管射频消融术后早期及晚期复发有关,其中Pd≥60 ms对预测持续性房颤术后晚期复发有一定的价值,其中阴性预测价值更高。展开更多
文摘目前转换波AVO(Amplitude Versus Offset)反演或纵波、转换波联合AVO反演是基于Aki等的反射系数近似公式,通常反演结果为上、下层速度比值和速度平均比值.本文在Shuey和郑晓东近似公式的基础上,运用最小平方算法,提出一种P-P波和P-SV波联合AVO反演下层介质纵、横波速度及泊松比的方案,并应用于双层含气砂岩模型上,误差在10%以内.此方案要求上、下层物性差别不大且入射角小于30°,但不需要速度比值为常数2的假设.
文摘BACKGROUND： Activation of the sympathetic nervous system plays an important role in regulating cardiovascular actions. P wave parameters can provide general information on central cardiovascular autonomic regulatory responses, which are altered in patients with anxiety disorders and depression. In particular, there are no reports addressing changes in P wave duration and dispersion. OBJECTIVE： To compare the differences in P wave duration and P wave dispersion between patients with anxiety disorders and depression, because patients with anxiety disorders and depression develop abnormal electrocardiograms. DESIGN, TIME AND SETTING： A non-randomized concurrent controlled study was performed. Patients with depression and general anxiety disorders were admitted at the psychiatry outpatient clinics of the Medical Faculty of Duezce University of Turkey between May 2005 and October 2006. PARTICIPANTS： A total of 71 consecutive patients with depression and anxiety disorders, as well as 50 physically and mentally healthy age- and gender-matched controls were selected. METHODS： Electrocardiogram records were obtained at the time of admission to the outpatient clinics. MAIN OUTCOME MEASURES： P wave duration and P wave dispersion were measured. RESULTS： Both the maximum （Prnax） and minimum （Pmin） P wave duration were greater in patients with psychiatric disorders than in healthy controls. Pmax was significantly greater in patients with depression or anxiety disorders （Bonferroni test, P 〈 0.017）. The P wave dispersion was similar between patients and controls （P 〉 0.017）. P waves were similar between panic patients and other anxiety patients. Beck depression results were positively correlated with Prawn and Prnax （r= 0.374, 0.302, P = 0.013, 0.049, respectively）, and not associated with P wave dispersion （P 〉 0.05）. CONCLUSION： Psychiatric disorders are associated with increases in Prnax, but not with P wave dispersion. The P wave changes were associated with the degree of depression.
文摘Objective: The aim of the study was to investigate the impact of P-maximum and P-wave dispersion on the long term clinical outcome after successful percutaneous balloon mitral valvuloplasty (PBMV) in patients with mitral stenosis (MS) and sinus rhythm. Also to test the correlation between P-variables and right ventricular function and pulmonary artery pressure before and after PMBV. Methods: Eighty-five patients undergoing PMBV were enrolled in this study. We evaluated P-maximum, P-minimum and P-wave dispersion before and one month after PBMV. We studied the changes in pulmonary arterial pressure (PAP), left atrial (LA) dimension, mitral diastolic gradient, and mitral valve area, in addition to the changes in right ventricular function utilizing tissue Doppler assessment both before and after PMBV, in addition the role of the P-wave dispersion in predicttion of late cardiac events. Results: There were significant decreases in mean diastolic gradient, PAP, and LA size and significant improvement in right ventricular tissue Doppler indices after PMBV. Ac- company these hemodynamic changes after PMBV. P-maximum and P-wave dispersion were found to be decreased (P < 0.001). Patients developed cardiac events during follow-up had a higher P-maximum and P-dispersion than those without late cardiac events (P < 0.001). Moreover the changes in P-maxi- mum and P-dispersion before and after PMBV in patients with cardiac events were not significant, while P-maximum and P-dispersion significantly (P < 0.002) decreased in patients without events It was revealed with linear regression and correlation analy- sis that the degree of and the changes in P-maximum and P-wave dispersion were correlated with devel- opment of late cardiac events after PMBV, with Cut-off values of ≥62.8 msec for P-wave dispersion and 118 mes for P-maximum.ROC curve showed AUC of 0.919 for P-wave dispersion and 0.913 for P-maximum (P < 0.001). Conclusion: P-wave maximum and dispersion are significantly increased in patients with mitral stenosis. These changes decreased significantly after PMBV. The P-maximum and P-wave dispersion changes were correlated with significant impairment of right dysfunction and the degree of pulmonary artery pressure. P-maximum and P-wave dispersion could be considered as independent predictors of late outcome of patients with MS after successful PMBV (AF, recurrent hospital admission, embolic phenomenon deterioration of right ventricular function).
文摘目的:探讨持续性心房颤动(房颤)导管射频消融术后P波时限及离散度与术后早期与晚期复发房颤的关系。方法:连续入选80例首次行导管射频消融术的持续性房颤患者,其中男性46例,女性34例,平均年龄(60.6±8.1)岁,平均随访(9.3±2.9)个月。根据3个月之内(早期)和之外(晚期)复发房颤情况,分为两个对比组:早期复发组和早期未复发组;晚期复发组和晚期未复发组。所有患者术后24 h内均记录12导联心电图,并测量P波时限,计算出最长P波时限(Pmax),最短P波时限(Pmin),以及两值之差即P波离散度(Pd),分析P波时限及离散度与术后早期与晚期复发房颤的关系。结果:17例患者早期复发房颤,与早期未复发组患者比较,Pd明显增长[(74.35±17.78) ms vs (60.73±18.37) ms,P=0.008];12例早期复发患者(70.6%)出现延迟恢复,未发现早期复发为晚期复发预测因子。14例患者晚期复发房颤,与晚期未复发组患者相比,Pd明显增长[(75.71±16.49)ms vs (61.06±18.59) ms,P=0.008]。通过观察不同临界值,发现Pd≥60 ms对预测术后晚期复发房颤有一定价值,敏感度85%、特异度50%、阳性预测值26.7%、阴性预测值94.3%。结论:Pd与持续性房颤导管射频消融术后早期及晚期复发有关,其中Pd≥60 ms对预测持续性房颤术后晚期复发有一定的价值,其中阴性预测价值更高。
