Objective To evaluate left univentricular （LUV） pacing for cardiac resynchronization therapy （CRT） using a rate-adaptive atrioven- tricular delay （RAAVD） algorithm to track physiological atrioventricular delay ...Objective To evaluate left univentricular （LUV） pacing for cardiac resynchronization therapy （CRT） using a rate-adaptive atrioven- tricular delay （RAAVD） algorithm to track physiological atrioventricular delay （AVD）. Methods A total of 72 patients with congestive heart failure （CHF） were randomized to RAAVD LUV pacing versus standard biventricular （BiV） pacing in a 1 ： 1 ratio. Echocardiography was used to optimize AVD for both groups. The effects of sequential BiV pacing and LUV pacing with optimized A-V （right atrio-LV） delay using an RAAVD algorithm were compared. The standard deviation （SD） of the S/R ratio in lead VI at five heart rate （HR） segments （Rs/R-SD5）, defined as the ＂tracking index,＂ was used to evaluate the accuracy of the RAAVD algorithm for tracking physiological AVD. Results TheQRS complex duration （132 ± 9.8 vs. 138± 10ms, P 〈 0.05）, the time required for optimization （21 ±5 vs. 50±8min, P〈 0.001）, the mitral regurgitant area （1.9 ± 1.1 vs. 2.5 ± 1.3 em2, P 〈 0.05）, the interventricular mechanical delay time （60.7 ± 13.3 ms vs. 68.3 ± 14.2 ms, P 〈 0.05）, and the average annual cost （13,200 ± 1000 vs. 21,600 ± 2000 RMB, P 〈 0.001） in the RAAVD LUV pacing group were significantly less than those in the standard BiV pacing group. The aortic valve velocity-time integral in the RAAVD LUV pacing group was greater than that in the standard BiV pacing group （22.7 ± 2.2 vs. 21.4 ± 2.1 cm, P 〈 0.05）. The Rs/R-SD5 was 4.08 ± 1.91 in the RAAVD LUV pacing group, and was significantly negatively correlated with improved left ventricular ejection fraction （LVEF） （ALVEF, Pearson＇s r = -0.427, P = 0.009）, and positively correlated with New York Heart Association class （Spearman＇s r - 0.348, P 0.037）. Conclusions RAAVD LUV pacing is as effective as standard BiV pacing, can be more physiological than standard BiV pacing, and can de- crease the average annual cost of CRT.展开更多
Objective To investigate the efficacy of continuous renal replacement therapy(CRRT)versus intermittent hemodialysis(IHD)in patients with severe acute renal failure(ARF).Methods One hundred and ninety -three severe ARF...Objective To investigate the efficacy of continuous renal replacement therapy(CRRT)versus intermittent hemodialysis(IHD)in patients with severe acute renal failure(ARF).Methods One hundred and ninety -three severe ARF patients who received renal support between December 1978 and December 1998 were involved in this study.Of them,101(52.3%)were treated with CRRT(CRRT group),and 92(47.7%)with IHD(IHD group).Results Sixty(59.4%)patients in the CRRT group got through the acute phase of disease and 41 (40.6%)patients did not survive while in the IHD group 59(64.1%)patients survived and 33(35.9%)patients did not.No significant difference in survival rate was found between the two groups.24 of 64 patients(37.5%)in the CRRT group with multiple organ dysfunction syndrome(MODS)survived,while in the IHD group,8 out of 44(27.3%)survived,their survival rate was much lower than that in the CRRT group.Patients in CRRT group were more severely iii,as manifested by lower mean arterial pressure,higher APACHE Ⅱ score,more dysfunctioned organs and requiring mechanical ventilation and vasopressor support as compared with patients in the IHD group,CRRT was found to improve hemodynamic stability with a better fluid balance and control of biochemical status,increased nutritional intake and a shorter duration of acute renal failure(P ＜ 0.05).Conclusion CRRT perhaps may be the best choice in the treatment of severe ARF patients,for it can offer several distinct advantages compared to IHD.These may contribute to improving the survival rate of ARF patients,particularly those that are critically ill patients.展开更多
文摘Objective To evaluate left univentricular （LUV） pacing for cardiac resynchronization therapy （CRT） using a rate-adaptive atrioven- tricular delay （RAAVD） algorithm to track physiological atrioventricular delay （AVD）. Methods A total of 72 patients with congestive heart failure （CHF） were randomized to RAAVD LUV pacing versus standard biventricular （BiV） pacing in a 1 ： 1 ratio. Echocardiography was used to optimize AVD for both groups. The effects of sequential BiV pacing and LUV pacing with optimized A-V （right atrio-LV） delay using an RAAVD algorithm were compared. The standard deviation （SD） of the S/R ratio in lead VI at five heart rate （HR） segments （Rs/R-SD5）, defined as the ＂tracking index,＂ was used to evaluate the accuracy of the RAAVD algorithm for tracking physiological AVD. Results TheQRS complex duration （132 ± 9.8 vs. 138± 10ms, P 〈 0.05）, the time required for optimization （21 ±5 vs. 50±8min, P〈 0.001）, the mitral regurgitant area （1.9 ± 1.1 vs. 2.5 ± 1.3 em2, P 〈 0.05）, the interventricular mechanical delay time （60.7 ± 13.3 ms vs. 68.3 ± 14.2 ms, P 〈 0.05）, and the average annual cost （13,200 ± 1000 vs. 21,600 ± 2000 RMB, P 〈 0.001） in the RAAVD LUV pacing group were significantly less than those in the standard BiV pacing group. The aortic valve velocity-time integral in the RAAVD LUV pacing group was greater than that in the standard BiV pacing group （22.7 ± 2.2 vs. 21.4 ± 2.1 cm, P 〈 0.05）. The Rs/R-SD5 was 4.08 ± 1.91 in the RAAVD LUV pacing group, and was significantly negatively correlated with improved left ventricular ejection fraction （LVEF） （ALVEF, Pearson＇s r = -0.427, P = 0.009）, and positively correlated with New York Heart Association class （Spearman＇s r - 0.348, P 0.037）. Conclusions RAAVD LUV pacing is as effective as standard BiV pacing, can be more physiological than standard BiV pacing, and can de- crease the average annual cost of CRT.
文摘Objective To investigate the efficacy of continuous renal replacement therapy(CRRT)versus intermittent hemodialysis(IHD)in patients with severe acute renal failure(ARF).Methods One hundred and ninety -three severe ARF patients who received renal support between December 1978 and December 1998 were involved in this study.Of them,101(52.3%)were treated with CRRT(CRRT group),and 92(47.7%)with IHD(IHD group).Results Sixty(59.4%)patients in the CRRT group got through the acute phase of disease and 41 (40.6%)patients did not survive while in the IHD group 59(64.1%)patients survived and 33(35.9%)patients did not.No significant difference in survival rate was found between the two groups.24 of 64 patients(37.5%)in the CRRT group with multiple organ dysfunction syndrome(MODS)survived,while in the IHD group,8 out of 44(27.3%)survived,their survival rate was much lower than that in the CRRT group.Patients in CRRT group were more severely iii,as manifested by lower mean arterial pressure,higher APACHE Ⅱ score,more dysfunctioned organs and requiring mechanical ventilation and vasopressor support as compared with patients in the IHD group,CRRT was found to improve hemodynamic stability with a better fluid balance and control of biochemical status,increased nutritional intake and a shorter duration of acute renal failure(P ＜ 0.05).Conclusion CRRT perhaps may be the best choice in the treatment of severe ARF patients,for it can offer several distinct advantages compared to IHD.These may contribute to improving the survival rate of ARF patients,particularly those that are critically ill patients.
