Objective To explore the feasibility of right ventricular outflow tract (RVOT) septal pacing. Methods Fifty-two patients implanted with pacemaker were randomly divided into two groups. One group underwent the RVOT septal pacing with active fixation electrodes (active fixation electrodes group, 22 cases),and the other group underwent the right ventricular apical pacing with passive fixation electrodes (passive fixation electrodes group, 30 cases). The parameters of two groups in operation were recorded. Results The successful rate of RVOT septal pacing was 100%, active fixation electrodes group took more time to plant electrodes and expose in X-ray than passive fixation electrodes group [ (56.13±1.18)min vs (15.42±1.24) min, (18.77±6.14) min vs (10.12±8.14) min, P<0.05]. The width of the QRS wave of active fixation electrodes group was narrower than that of passive fixation electrodes group [(0.14±0.02)ms vs (0.16±0.04) ms, P< 0.05]. The parameters of two groups were stable in follow-up period and none of electrodes was extracted. Conclusion The usage of active fixation electrodes in patients with RVOT septal pacing is feasible and safe.

Objective To explorethe complication and its cause and treatment of pace markers implantation in older patients. Methods To analyze the complication in 103 older patients with pace markers implantation. Resuits 5 patients happened complication(4.8 % ), the common complications related to operation were blood effusion and he matoma formation in pocket 4 cases,pocket infection 1 case. Occurrence of blood effusion was related to aspirin administration. Conclusion The older patient with pace marders implantation is safe.

Objective To observe the clinical effect and safety of platdet GP Ⅱb/Ⅲa receptor antagonist firofiban on acute coronary syndrome(ACS)patients with nO reflow after intevention procedure.Methods 48 ACS patients with no reflow were randomly divided into tirofiban group(n=26)and control group(n=22),the tirofiban group received intravenous tirofiban for 48-36homs,control group received nitroglycerin and urokinase.The rate of the TIMI grade offorward flow and the primary end pints(death,persistent myocardial isehemic and new onset myocardial infarction)and adverse reactions of drags were observed Resalts Tirofiban improved target vessel TIMI flow significantly than control groug(73.8%vs 18.2%,P＜0.01),the rate of the main end point events significantly decreased(15.4%vs 63.6%,P＜0.05),the bleeding complications was similar between two groups,no severe bleeding events occurred.Condusion Tirofiban is effecfive and safe in treating ACS patients with no reflow.

Objective To investigate the common problems and countermeasure of using ultrasound-guided modified Seldinger technique in peripherally inserted central catheter (PICC) placement Method The clinical data of 140 patients who underwent PICC placement using ultrasound-guided modified Seldinger technique were retrospectively analyzed. Results The success rate of catheterization was 98. 6% among these 140 patients,with 135 (96. 4% ) succeeded after a single attempt and 5 (3. 6% ) after 2 attempts. Besides, 7. 1% (n = 10) had difficulty in inserting the guide wire, 3. 6% (n =5) had difficult catheteration, 2. 1% (n =3) met resistance when inserting catheter into ipsilateral subclavian vein, 2. 1 % (n = 3 ) experienced dystopia of inserting catheter into internal jugulular vein, and 1.4% (n = 2) experienced the bending of PICC in the superior vena cava and axillary vein. All of these problems were handled successfully. Conclusions The common problems of PICC placement include puncture failure, difficulty in inserting guide wire, and difficult catheteration. A good knowledge of these problems will help increase the success rate.

Objective To analyze the immediate and following up result of 122 patients with acute myocardlal infarction(AMI)which underwent emergency percutaneous coronary interventlon(PCI).Methods 122 cases of AMI patients underwent the emergency PCI by transfemoral artery approach during June 1998 to December 2005.119 casea performed primary PCI,3 performed rescue PCI.Results The successful rate of vessel visualization and operation were 95.1%.93.4%.respectively.5 eases were with the help of intra-aortic balloon pumping.Subacute instent thrombosis occurred in 2 patients.In-hopital mortality was 4.1% (5/122).The left ventricular ejection fraction in echocardiography one after week was(0.55±0.16).Average hospital day is(9.5±5.8)(1～36).6-month mortality was 5.7%(7/122).Conclusion Primary PCI expanded the indication for the treatment of STEMI patients wlth establishment of patent infarct related artery and normal blood flow,increased tlle survival of high-risk patients,and shortened the hospitalization.Rescue PCI was an effective measure for the patients failing to intravenous thrombolysis.

Objective To evaluate the methods for the prevention of internal jugular vein malposition of peripherally inserted central catheter (PICC) in patient with limited neck motion.Methods 210 patients who underwent PICC placement using ultrasound-guided modified Seldinger technique were divided into observation group (n =106) and control group (n =104) with a random number table.Ultrasound probe compression on the internal jugular vein was used in the observation group,while finger compression was used in the control group.The 2 groups were compared in terms of incidence of internal jugular vein malposition,accuracy of PICC tip position in X-ray,and incidence of complications.Results Incidence of PICC malposition was significantly lower in the observation group than the control group [3 (2.8％) vs.36 (34.6％),P =0.000].The accuracy of PICC tip position in both groups was 100％.No complication was observed in the observation group,while the rate of complication in the control group was 4.8％,with a statistically significant difference (P =0.022).Conclusion The ultrasound probe compression method can significantly lower the incidence of internal jugular vein malposition of PICC and is safer than the finger compression method.

Objective To investigate the effect of stress-related hyperglycemia on myocardial function of patients with cardiac disorder after non-cardiac surgery.Methods The clinical data of 211 patients having undergone thoracic or abdominal operations in Department of Critical Care Medicine of Sun Yat-sen University Cancer Center were retrospectively analyzed. According to the postoperative average blood glucose level in the following 3 days after surgery and the patients' history of cardiac disorder, they were divided into four groups: without hyperglycemia (blood glucose ≤ 10 mmol/L) and cardiac disorder group (HG0CV0 group), without hyperglycemia but with cardiac disorder group (HG0CV1 group), with hyperglycemia (blood glucose > 10 mmol/L) but without cardiac disorder group (HG1CV0 group) and with hyperglycemia and cardiac disorder group (HG1CV1 group). The correlations between the blood glucose and each level of the following items: high-sensitivity cardiac troponin I (hs-cTnI), brain natriuretic peptide (BNP), myocardial zymogram aspartate aminotransferase (AST), creatine kinase (CK), MB isoenzyme of creatine kinase (CK-MB), lactic dehydrogenase (LDH), lactic dehydrogenase isoenzyme (LDH-1), myoglobin (MYO), α- hydroxybutyrate dehydrogenase (HBDH) in each group were analyzed.Results The postoperative blood glucose levels of all 211 patients were significantly higher than those before operation (mmol/L: 8.7±0.2 vs. 5.7±0.2,P < 0.05), and the blood glucose level more than 6.1 mmol/L in postoperative 179 patients accounted for 84.8% of the total. In HG0CV0 group, the postoperative blood glucose level was positively correlated with MYO and AST [r values were 0.193, 0.307; 95% confidence intervals (95%CI) were 0.010 - 0.362, 0.096 - 0.479;P values were 0.038, 0.003]. There were no correlations between postoperative blood glucose level and hs-cTnI, BNP, LDH, LDH-1, HBDH, CK and CK-MB (allP > 0.05). In HG0CV1 group, the postoperative blood glucose level was negatively correlated with hs-cTnI level (r = -0.609, 95%CI = -0.810 to -0.264,P = 0.001). There were no correlations between postoperative blood glucose level and the levels of BNP, MYO, AST, LDH, LDH-1, HBDH, CK and CK-MB (allP > 0.05). In HG1CV0 group, there were no correlations between postoperative blood glucoselevel and hs-cTnI, BNP, MYO, AST, LDH, LDH-1, HBDH, CK and CK-MB (allP > 0.05). In HG1CV1 group, the postoperative blood glucose level was positively correlated with hs-TnI level (r = 0.837, 95%CI = 0.476 - 0.984,P = 0.001). There were no correlations between postoperative blood glucose level and the levels of BNP, MYO, AST, LDH, LDH-1, HBDH, CK and CK-MB (allP > 0.05).Conclusion The early stress-related hyperglycemia after non-cardiac surgery may have a protective effect on myocardial function of patients with cardiac disorder.

Objective:To evaluate the long-term impact of three different outdoor activity intervention strategies on the prevalence of myopia among school-aged children in China.Methods:Cross-sectional data from the Refractive Error Study in Children (RESC) on the baseline prevalence of myopia and 10-year longitudinal data from the Guangzhou Twin Eye Study (GTES) on the baseline incidence of myopia were utilized.The effect size of outdoor activity intervention was derived from longitudinal data of the Guangzhou Outdoor Activity Longitudinal Study (GOALS). Three intervention strategies were proposed: intervention for children in grades 1 to 6 (Strategy A), intervention for children in grades 1 to 3 (Strategy B), and intervention for children from the last year of kindergarten to grade 3 (Strategy C). Outdoor activity interventions across all strategies included an extra 40 minutes of daily outdoor activity time.Simulated analyses assumed that the prevalence of myopia would decrease with declining incidence and increasing school grade, and the degree of myopia among highly myopic children would decrease with delayed myopia onset.This study was approved by the Ethics Committee of Zhongshan Ophthalmic Center (No.2006-5).Results:With prolonged intervention time, the overall prevalence of myopia in children showed a significant declining trend.After 5 years of implementation, Strategy A resulted in a decrease in myopia prevalence from 34.67% to 25.71%, which decreased to 24.89% after 10 years, with an average annual reduction of 0.98%.Strategies B and C had similar long-term effects, with myopia prevalence after 10 years being 26.00% and 26.20% respectively, with an average annual reductions of 0.87% and 0.85%.Strategy A yielded the greatest reduction in myopia severity, with a decrease of -5.94 D after 5 years and -5.88 D after 10 years in the initial 15-year-old highly myopic individuals.Strategy B followed with -6.08 D and -6.02 D after 5 and 10 years, respectively.Conclusions:Implementing intensified outdoor activity intervention among children in grades 1 to 6 may be the recommended strategy to reduce the overall prevalence of myopia in regions with high rates of myopia among school-aged children.