Objective To evaluate left ventricular systolic synchrony in patients with Ⅲ grade atrio-ventricular block(Ⅲ grade AVB) after pacemaker implantation by real-time three-dimensional echocardiography. Methods Methods Twelve patients with Ⅲ grade AVB implanted by VVI pacemaker, seven patients with Ⅲ grade AVB implanted by DDD pacemaker, twenty subjects with normal LV function were examined by Philips iE33 with a X3-1 probe. Results The minimal excursion in patients with Ⅲ grade AVB implanted by VVI pacemaker and DDD pacemaker was less than that in subjects with normal LV function (P <0.05) ,and two "bull eyes" displayed that some regional systolic timing delayed or ahead, but also some regional systolic excursion hypokinesis or dykinesis. Parameter index [including Tmsv 16-SD, Tmsv 12-SD, Tmsv 6-SD, Tmsv 16-Dif, Tmsv 12-Dif, Tmsv 6-Dif, Tmsv 16-SD (%), Tmsv 12-SD (%), Tmsv 6-SD (%), Tmsv 16-Dif (%), Tmsv 12-Dif (%), Tmsv 6-Dif(%)] of 17 segment time to minimal systolic volume in patients with Ⅲ grade AVB implanted by VVI pacemaker and DDD pacemaker was more than that in subjects with normal LV function (all P < 0.05). Conclusions Real-time three-dimensional echocardiography can rapidly evaluate left ventricular systolic synchrony in patients with Ⅲ grade AVB implanted by DDD pacemaker and VVI pacemaker.

Objective To assess whether echocardiographic parameters of M-mode,pulsed-wave Doppler and tissue Doppler imaging which were usually used for selecting cardiac resynchronization therapy (CRT) candidates could predict CRT responders.Methods Twenty-nine patients with NYHA class Ⅲ or Ⅳ heart failure,left ventricular ejection fraction(LVEF)≤35%,QRS≥130 ms were enrolled.All of them underwent biventricular pacemaker implantation.The septal-to-posterior wall motion delay(SPWMD) from M-mode recording,and the standard deviation of time to peak systolic velocity(Ts-SD) were used to evaluate intraventricular dyssynchrony.The interventricular mechanical delay (IVMD) by pulsed Doppler echocardiography was calculated by subtracting the right ventricular preejection intervals (RV-PEI:the onset of the QRS on the electrocardiogram to the onset of pulmonary outflow) from the left ventricular preejection intervals (LV-PEI:the onset of the QRS on the electrocardiogram to the onset of aortic outflow).At least 15 % reduction in left ventricular end-systolic volume(LVESV) at the 6-month after CRT was defined as responder.Results In the 29 patients,there were 20 (68.97%) responders.The area under the receiver operating curve(ROC) of SPWMD,Ts-SD,LV-PEI,RV-PEI and IVMD to predict CRT responders was 0.448 (95% CI 0.184-0.712,P＞0.05),0.557 (95% CI 0.317-0.798,P＞0.05),0.479 (95% CI 0.186-0.773,P＞0.05),0.568 (95 % CI 0.272-0.863,P＞0.05) and 0.411 (95% CI0.136-0.687,P＞0.05),respectively.Conclusions M-mode echocardiography,pulsed Doppler and tissue Doppler imaging failed to predict CRT responders.New echocardiographic techniques including threedimensional echocardiography and speckle tracking image will be investigated,and may improve the predictive power.

ObjectiveTo assess left ventricular (LV) twist in Beagle dogs with rapid-pacing induced heart failure by 3-dimensional speckle tracking imaging.MethodsSeventeen adult beagle dogs underwent rapid right ventricular pacing (RVP) to induce heart failure.Right ventricles were paced at 260 beats/min for 3 weeks.Apical full-volume acquisition of the LV was obtained in conscious animals at baseline and the end of 3-week rapid pacing.Peak LV apical rotation(AP-Prot) and basal rotation (MV-Prot) accompanied with peak twist (Ptw) and torsion were automatically calculated by TomTec 4D LV Analysis 3.0 software.The relation between LV twist and QRS duration was further studied.Results After 3 weeks of rapid ventricular pacing,AP-Prot,MV-Prot,Ptw decreased significantly [At-Prot:(13.96 ± 2.00) ° vs (5.85 ± 0.58)°；MV-Prot:(3.34± 0.38)° vs (2.13 ± 0.44)°； Ptw:(16.31 ± 2.01)° vs (7.08 ± 1.16)°,all P ＜0.05].Dogs with heart failure were divided into two groups according to the QRS duration:pQRSd group with QRS≥100 ms and nQRSd group with QRS＜100 ms.No significant difference was found in AP-Prot and MV-Prot between two groups ( P ＞0.05).In the pQRSd group,the peak of apical rotation occurred earlier than the peak of basal rotation [(162.89 ± 14.33) ms vs (91.43 ± 15.45) ms,P ＜0.05],which might resulted in further worsening of peak LV twist [pQRSd:(6.02 ± 0.74)° vs nQRSd:(7.91 ± 0.53)°,P ＜0.05].Conclusions LV twist dynamics was a good indicator of LV systolic function and had the potential to evaluate LV systolic dyssynchrony.

Objective To establish a HPLC method for the determination of effective components in Radix Notoginseng in San Xiong Zhitong Ointment.Methods Kromasil KR100-5 C18 column(250 mm?4.6 mm,5 ?m)and gradient elution were used.Solvent A was acetonitrile and solvent B was water.The detection wavelength was set at 203 nm.Results The four components were isolated well.The linearity was fine with the recoveries of 98 %～100 %.Conclusion The quantitative method for determining the ingredient of San Xiong Zhitong Ointment is simple,feasible and repeatable,and is beneficial for quality control of San Xiong Zhitong Ointment.

Objective To assess left ventricular (LV) twist in a rapid pacing induced heart failure canine model undergoing cardiac resynchronization therapy (CRT) by three-dimensional speckle tracking imaging (3D-STI).Methods Rapid right ventricular pacing (RVP) was utilized in 22 adult beagle dogs for 3 weeks to induce heart failure.Then 15 dogs received CRT for 2 weeks and others were treated as control.Apical full-volume acquisition of the LV was obtained in conscious animals at baseline,the end of 3-week RVP and the end of 2-week CRT.Peak LV apical (AP-Prot) and basal rotation (MV-Prot) along with peak twist (Ptw) and torsion (Ptor) were automatically calculated by TomTec 4D LV Analysis 3.0 software to identify the ideal parameter in predicting treatment response of CRT.Results After 2 weeks of CRT,LV ejection fraction(LVEF) increased and LV end-systolic volume(LVESV) decreased significantly in dogs with heart failure.CRT treatment response,defined as improvement of LVESV≥15％,was observed in 9 dogs.Significant difference was found in Ptw [(7.43 ± 0.61) vs (6.06 ± 0.89)°,P ＜0.05] and Ptor [(1.43 ± 0.45) vs (0.67 ± 0.36)°/cm,P ＜0.05] between responders and nonresponders.Ptw and Ptor predicted CRT response with satisfying sensitivity as 89％ and 85％,specificity as 83％ and 84％,respectively.Conclusions Peak twist and torsion evaluated by 3D-STI represented overall LV twist and demonstrated potential prediction value for treatment response of CRT.

Objective To investigate new parameters to predict the response to cardiac resynchronization therapy (CRT) by using real-time three-dimensional echocardiography (RT3DE) and speckle tracking imaging(STI). Methods Twenty-one adult beagle dogs were divided into three groups:group A (CRT group, n =10) ,group B (heart failure group, n =7) and group C (control group, n =4).Seventy patients who accepted CRT and were followed up 6 months after CRT were enrolled. Response to CRT was defined as a ≥15％ decrease in left ventricular end-systolic volume. RT-3DE parameters were the dispersion of time to minimum regional volume for 16 segments (Tmsv16-SD) ,and the ratio of Tmsv16-SD to R-R interval (SDI). STI parameters were the ratios of standard deviation of the time to peak radial and circumferential strain at midventricular level to R-R interval (Trs-6SD,Tcs-6SD). Results In experimental study,Tmsv-16SD, Trs-6SD, Tcs-6SD had negative relationship with left veutricular ejection fraction (r were - 0. 86, - 0.75, - 0.83 respectively, all P ＜0.01 ). Trs-6SD was the strongest predictor to CRT. A cut-off value of Trs-6SD≥12.2％ was able to predict response to CRT with a sensitivity of 83.3％ and a specificity of 100％. Clinical studies found SDI was the strongest predictor to CRT. A cut-off value of SDI≥6.55％ was able to predict response to CRT with a sensitivity of 80. 0％ and a specificity of 81.8％.Conclusions RT-3DE and STI can assess left ventricular dyssynchrony, and are promising methods to predict the response to CRT.

Objective To evaluate the effects of different right ventricular pacing sites on left ventricular systolic synchrony using tissue Doppler imaging(TDI).Methods A tota[of sixty-nine patients with indications for permanent pacemaker implantation were enrolled sequentially by Pace-ROAD study(Pacemaker-right ventricular outflow tract and apex study,a randomized control study).They were randomized to RVOT pacing group(group A)or RVA pacing group(group B).Echocardiographic study with TDl was performed before and after 3 month follow up,and the data were analysed off-line.The peak velocity(Vs),the time to the peak of S wave(Ts)of all 12 basal and middle segments of left ventricle were measured,and then the standard deviation of Ts(Ts-SD),the average of Vs(Vs-M)were calculated.Results Thirty-six patients were randomized to group A,while the other 33 patients to group B.In each group,one patient was rejected due to non-pacing rhythm during follow-up.After 3 month pacing,the Ts-SD of group A was significantly shorter than that of group B[(23.63±2.32)ms vs(31.54±2.93)ms.P=0.0387-].In the patients with the basal Ts-SD longer than 32.6 ms(group A2 and group B2),the Ts-SD was significantly shortened than the baseline in group A2 during follow-up,while no significant difference was found in group B2.And the follow-up Ts-SD of group B2 was significantly longer than that of group A2 r(38.19±18.34)ms vs(28.55±16.93)ms,P=0.0290].Conclusions RVOT pacing is associated with favorable left ventricular systolic synchrony than RVA pacing,especially in patients with worsened baseline systolic synchrony.

BACKGROUNDDual sensor (DS) for rate adaption was supposed to be more physiological. To evaluate its superiority, the DS (accelerometer [ACC] and minute ventilation [MV]) and normal sinus rate response were compared in a self-controlled way during exercise treadmill testing.

METHODSThis self-controlled study was performed in atrioventricular block patients with normal sinus function who met the indications of pacemaker implant. Twenty-one patients came to the 1-month follow-up visit. Patients performed a treadmill test 1-month post implant while programmed in DDDR and sensor passive mode. For these patients, sensor response factors were left at default settings (ACC = 8, MV = 3) and sensor indicated rates (SIRs) for DS, ACC and MV sensor were retrieved from the pacemaker memories, along with measured sinus node (SN) rates from the beginning to 1-minute after the end of the treadmill test, and compared among study groups. Repeated measures analysis of variance and profile analysis, as well as variance analysis of randomized block designs, were used for statistical analysis.

RESULTSFifteen patients (15/21) were determined to be chronotropically competent. The mean differences between DS SIRs and intrinsic sinus rates during treadmill testing were smaller than those for ACC and MV sensor (mean difference between SIR and SN rate: ACC vs. SN, MV vs. SN, DS vs. SN, respectively, 34.84, 17.60, 16.15 beats/min), though no sensors could mimic sinus rates under the default settings for sensor response factor (ACC vs. SN P-adjusted < 0.001; MV vs. SN P-adjusted = 0.002; DS vs. SN P-adjusted = 0.005). However, both in the range of 1 st minute and first 3 minutes of exercise, only the DS SIR profile did not differ from sinus rates (P-adjusted = 0.09, 0.90, respectively).

CONCLUSIONSThe DS under default settings provides more physiological rate response during physical activity than the corresponding single sensors (ACC or MV sensor). Further study is needed to determine if individual optimization would further improve adaptive performance of the DS.

Adult ; Aged ; Cardiac Pacing, Artificial ; methods ; Exercise ; physiology ; Exercise Test ; Female ; Humans ; Male ; Middle Aged ; Pacemaker, Artificial

Objective: To conduct a preliminary evaluation for the usability of Carelink remote monitoring system by clinical physician. Methods: A total of 215 patients received cardiovascular implantable electronic devices (CIED) with Carelink remote monitoring function from 12 hospitals in China between 2012-01 and 2013-10 were prospectively enrolled. The patient's mean age was (62.3±14.3) years including 108 male and 107 female. There were 54 physicians completed questionnaire survey. Based on the type of CIED, the patients were divided into3 groups: PM (pace maker) group,n=110, ICD (implantable cardioverter defibrillator) group,n=54 and CRT (cardiac resynchronization therapy) group,n=51. The patients received routine hospital visit at 3 months of CIED implantation and meanwhile, they performed device data transmission at 3 and 6 months of Carelink remote monitoring. The time physician spent to evaluate data was collected at 3 months and the questionnaire survey was completed by physician at 6 months after CIED implantation. Results: All 54 physicians felt that Carelink remote monitoring system was simple to operate and easy to use. There were 147 patients ifnished hospital visit at 3 months after CIED implantation, the mean time for physician to evaluate data was (14.8±8.4) min; 150 patients ifnished Carelink remote monitor at 3 months after CIED implantation, the mean time for physician to evaluate data was (8.2 ±4.6) min,P<0.0001.Conclusion: Carelink remote monitoring system was easy to use, it may save time in follow-up study which with high satisfaction in clinical practice.

Objective:To establish a predictive model for the progression of acute kidney injury (AKI) to stage 3 AKI (renal failure) in the intensive care unit (ICU), so as to assist physicians to make early and timely decisions on whether to intervene in advance.Methods:A retrospective analysis was conducted. Thirty-eight patients with AKI admitted to the intensive care medicine of the Third People's Hospital of Henan Province from January 2018 to May 2023 were enrolled. Patient data including acute physiology and chronic health evaluation Ⅱ (APACHEⅡ) upon admission, serum creatinine (SCr), blood urea nitrogen (BUN), daily urine output during hospitalization, and the timing of continuous renal replacement therapy (CRRT) intervention were recorded. Based on clinically collected pathological data, standardized creatinine value ratio mean polynomial fitting models were established as the first criterion for judging the progression to stage 3 AKI after data cleansing, screening, and normalization. Additionally, standardized creatinine value ratio index fitting models were established as the second criterion for predicting progression to stage 3 AKI.Results:A total of 38 AKI patients were included, including 25 males and 13 females. The average age was (58.45±12.94) years old. The APACHEⅡ score was 24.13±4.17 at admission. The intervention node was (4.42±0.95) days. Using a dual regression model approach, statistical modeling was performed with a relatively small sample size of statistical data samples, yielding a scatter index non-linear regression model for standardized creatinine value ratio data relative to day " n", with y = 1.246?2 x1.164?9 and an R2 of 0.860?1, indicating reasonable statistical fitting. Additionally, a quadratic non-linear regression model was obtained for the mean standardized creatinine value ratio relative to day " n", with y = -0.260?6 x2+3.010?7 x-1.612 and an R2 of 0.998?9, indicating an excellent statistical fit. For example, using a baseline SCr value of 66 μmol/L for a healthy individual, the dual regression model predicted that the patient would progress to stage 3 AKI within 3-5 days. This prediction was consistent when applied to other early intervention renal injury patients. Conclusion:The established model effectively predicts the time interval of the progression of AKI to stage 3 AKI (renal failure), which assist intensive care physicians to intervene AKI as early as possible to prevent disease progression.