| Abstract 1Risk Stratification and Prognostic Analysis of Subclinical Cardiac Implantable Electronic Devices Infection:Insight From Traditional Bacterial CultureBackground:Subclinical infection of cardiac implantable electronic devices(CIED)is a common condition and increases the risk of clinical infection.However,there are limited studies focused on risk stratification and prognostic analysis of subclinical CIED infection.Methods:Data from 418 consecutive patients undergoing CIED replacement or upgrade between January 2011 and December 2019 in Beijing Hospital were collected.All the patients were examined by traditional bacterial culture of generator pocket tissue obtained during the procedure.According to the culture results,patients were assigned to subclinical infection group and noninfection group.Risk factors and risk stratification were analyzed between the two groups.Clinical events were recorded during follow-up.Results:Among the patients included.50 patients(12.0%)were detected positive by bacterial culture of pocket tissues.The most frequently isolated bacteria were coagulasenegative staphylococci(CoNS,76.9%).Compared with the noninfection group,more patients in the subclinical infection group were taking immunosuppressive agents,received electrode replacement or CIED upgrade and temporary pacing.Univariable and multivariable Logistic regression analysis found that use of immunosuppressive agents(OR 6.95,95%CI 1.44-33.51,P=0.016)and electrode replacement or CIED upgrade(OR 6.73,95%CI 2.23-20.38,P=0.001)were significantly associated with subclinical CIED infection.Patients in the subclinical infection group had a higher PADIT(Prevention of Arrhythmia Device Infection Trial)score(median 2.0 vs 1.0,P=0.002).Compared with low-risk group,patients in high-risk group had a higher prevalence of subclinical infection(40.0%vs 10.3%,P=0.004).Meanwhile,compared with the low-risk group,patients in the intermediate/high-risk group had a higher risk of subclinical CIED infection(OR 3.43,95%CI 1.58-7.41,P=0.002).Restricted cubic spline confirmed a strong linear association between PADIT score and the odds ratio of subclinical CIED infection(P for linear trend=0.003).After a median follow-up time of 36.5 months,the endpoints between subclinical infection group and noninfection group were as follows:composite events(58.0%vs 41.8%,P=0.031),rehospitalization(54.0%vs 32.1%,P=0.002),cardiovascular rehospitalization(32.0%vs 13.9%,P=0.001),CIED infection(2.0%vs 0.5%,P=0.318),all-cause mortality(28.0%vs 21.5%,P=0.297)and cardiovascular mortality(10.0%vs 7.6%,P=0.574).Conclusions:The prevalence of subclinical CIED infection was 12.0%.The most common causative microorganisms were CoNS.Use of immunosuppressive agents and electrode replacement or CIED upgrade were significantly associated with subclinical CIED infection.The PADIT score had a significant value for stratifying patients at high risk of subclinical CIED infection.Subclinical CIED infection was associated with increased risks of composite events,rehospitalization,and cardiovascular rehospitalization.Abstract 2Long-term Prognosis and Risk Factors Analysis in Patients Undergoing Cardiac Implantable Electronic Devices Replacement:A Single Centre 5-year Cohort StudyBackground:With the increasing use of cardiac implantable electronic devices(CIED),CIED replacement has become more and more common in clinical practice,especially in elderly patients.However,there are few studies focused specially on the long-term clinical outcomes and risk factor analysis of this group of patients.Methods:Data from 457 consecutive patients undergoing CIED replacement between January 2011 and October 2016 in Beijing Hospital were collected.All the patients were regularly followed up for 5 years.The primary endpoint was all-cause mortality and the secondary endpoint included major adverse cardiovascular events(MACE)and CIEDrelated complications.Cox regression model was used to analyze the risk factors for prognosis.The restricted cubic spline(RCS)was used to evaluate the dose-response trend.The optimal cut-off values were determined by time-dependent receiver operating characteristic(ROC)curve.Patients were assigned to different groups based on the cutoff values.Kaplan-Meier survival curves and Log-rank test were used to compare the prognosis of different groups.Results:Of the 457 patients enrolled(mean age 76.8±10.1 years,56.7%male,singlechamber PPM 20.6%,dual-chamber PPM 76.1%,ICD 0.4%,CRT 2.8%),1-year and 5year survival rates were 94.5%and 70.9%,respectively.The top three leading causes of 1-year mortality were heart failure.acute myocardial infarction and pneumonia.cardiovascular death accounted for 48.0%.The top three leading causes of 5-year mortality were heart failure,malignancies and pneumonia,cardiovascular death accounted for 39.1%.Univariable and multivariable COX regression showed that age,body mass index(BMI),coronary artery disease,heart failure,chronic kidney disease,malignancies,Charlson comorbidity index(CCI),left ventricular ejection fraction(LVEF)during CIED replacement,ALVEF and New York Heart Association(NYHA)class Ⅲ/Ⅳ were independent predictors of 5-year all-cause mortality.While age,heart failure,CCI,LVEF during CIED replacement,ALVEF and NYHA class Ⅲ/Ⅳ were independent predictors of 5-year MACE.In the RCS analysis,age showed a nonlinear relationship with the hazard ratio of 5-year all-cause mortality(P for nonlinear trend<0.001)whereas BMI,CCI,LVEF during CIED replacement and ΔLVEF showed a linear relationship(all P for linear trend<0.001).The optimal cut-off values of age,BMI,CCI,LVEF during replacement and ΔLVEF determined by time-dependent ROC curve were as follows:81,22.2,1,60 and-8.The Kaplan-Meier survival curves and Log-rank test showed that patients with the following characters were at higher risk for both allcause mortality and MACE in 1-year and 5-year follow-up:more than or equal to 81 years of age,BMI less than or equal to 22.2 Kg/m2,CCI more than 1,LVEF during CIED replacement less than 60%,ΔLVEF less than or equal to-8 units and NYHA class Ⅲ/Ⅳ(all log-rank P values were less than 0.05 except insignificant difference in 1-year allcause mortality classified by ΔLVEF).Conclusions:In this study,1-year and 5-year overall survival rates in patients undergoing CIED replacement were 94.5%and 70.9%,respectively.Cardiovascular disease was the leading cause of mortality.Patients aged more than or equal to 81 years,with BMI less than or equal to 22.2 Kg/m2,with CCI more than 1,with LVEF during CIED replacement less than 60%,with ΔLVEF less than or equal to-8 units and with NYHA class Ⅲ/Ⅳ had a worse prognosis. |
