Haikun Bao

Rates of and Factors Associated With Infection in 200 909 Medicare Implantable Cardioverter-Defibrillator Implants Results From the National Cardiovascular Data Registry

Background— The rate of implantable cardioverter-defibrillator (ICD) infections has been increasing faster than that of implantation. We sought to determine the rate and predictors of ICD infection in a large cohort of Medicare patients. Methods and Results— Cases submitted to the ICD Registry from 2006 to 2009 were matched to Medicare fee-for-service claims data using indirect patient identifiers. ICD infections occurring within 6 months of hospital discharge after implantation were identified by ICD-9 codes. Logistic regression was used to examine factors associated with risk of ICD infection. Of 200 909 implants, 3390 patients (1.7%) developed an ICD infection. The infection rate was 1.4%, 1.5%, and 2.0% for single, dual, and biventricular ICDs, respectively (P<0.001). Generator replacement had a higher rate compared with initial implant (1.9% versus 1.6%, P<0.001). The factors associated with infection were adverse event during implant requiring reintervention (odds ratio [OR], 2.692; 95% confidence interval [CI], 2.304–3.145), previous valvular surgery (OR, 1.525; 95% CI, 1.375–1.692), reimplantation for device upgrade, malfunction, or manufacturer advisory (OR, 1.354; 95% CI, 1.196–1.533), renal failure on dialysis (OR, 1.342; 95% CI, 1.123–1.604), chronic lung disease (OR, 1.215; 95% CI, 1.125–1.312), cerebrovascular disease (OR, 1.172; 95% CI, 1.076–1.276), and warfarin (OR, 1.155; 95% CI, 1.060–1.257). Conclusions— Patients who developed an ICD infection were more likely to have had peri-ICD implant complications requiring early reintervention, previous valve surgery, device replacement for reasons other than battery depletion, and increased comorbidity burden. Efforts should be made to carefully consider when to reenter the pocket at any time other than battery replacement.

Sex Differences in Perceived Stress and Early Recovery in Young and Middle-Aged Patients With Acute Myocardial Infarction

Background— Younger age and female sex are both associated with greater mental stress in the general population, but limited data exist on the status of perceived stress in young and middle-aged patients presenting with acute myocardial infarction. Methods and Results— We examined sex difference in stress, contributing factors to this difference, and whether this difference helps explain sex-based disparities in 1-month recovery using data from 3572 patients with acute myocardial infarction (2397 women and 1175 men) 18 to 55 years of age. The average score of the 14-item Perceived Stress Scale at baseline was 23.4 for men and 27.0 for women (P<0.001). Higher stress in women was explained largely by sex differences in comorbidities, physical and mental health status, intrafamily conflict, caregiving demands, and financial hardship. After adjustment for demographic and clinical characteristics, women had worse recovery than men at 1 month after acute myocardial infarction, with mean differences in improvement score between women and men ranging from −0.04 for EuroQol utility index to −3.96 for angina-related quality of life (P<0.05 for all). Further adjustment for baseline stress reduced these sex-based differences in recovery to −0.03 to −3.63, which, however, remained statistically significant (P<0.05 for all). High stress at baseline was associated with significantly worse recovery in angina-specific and overall quality of life, as well as mental health status. The effect of baseline stress on recovery did not vary between men and women. Conclusions— Among young and middle-aged patients, higher stress at baseline is associated with worse recovery in multiple health outcomes after acute myocardial infarction. Women perceive greater psychological stress than men at baseline, which partially explains women’s worse recovery.

Use of Remote Monitoring of Newly Implanted Cardioverter-Defibrillators Insights From the Patient Related Determinants of ICD Remote Monitoring (PREDICT RM) Study

Background— Current guidelines recommend using remote patient monitoring (RPM) for implantable cardioverter-defibrillators, but the patterns of adoption of this technology have not been described. Successful use of RPM depends on (1) the enrollment of the patient into an RPM system and (2) subsequent activation of RPM by the enrolled patient. We examined RPM enrollment and activation rates and the patient, physician, and institutional determinants of RPM use. Methods and Results— Information about the use of RPM-capable devices was obtained from the Boston Scientific Corporation ALTITUDE program and linked to the National Cardiovascular Data Registry ICD Registry. Patients were first categorized as RPM-enrolled and RPM-not enrolled, and the RPM-enrolled patients were further categorized into RPM-active and RPM-inactive groups based on whether they transmitted RPM data. Variables associated with RPM enrollment and activation were identified with the use of multivariable logistic regression. Among 39 158 patients with newly implanted RPM-capable devices, 62% (n=24 113) were RPM-enrolled. Of those enrolled, 76% (n=18 289, or 47% of the entire cohort) activated their device. RPM enrollment was highly variable among institutions. The hospital-specific median odds ratio for RPM enrollment was 3.43, signifying that physician or institutional factors are associated with RPM enrollment. In contrast, the hospital-specific median odds ratio for RPM activation was 1.69. Age, race, health insurance, geographic location, and health-related factors were similarly associated with both RPM enrollment and activation. Conclusions— RPM technology is used in less than half of eligible patients. Lack of enrollment into RPM systems is the major cause of underutilization, and this primarily relates to the local practice environment. # Clinical Perspective {#article-title-28}Background— Current guidelines recommend using remote patient monitoring (RPM) for implantable cardioverter-defibrillators, but the patterns of adoption of this technology have not been described. Successful use of RPM depends on (1) the enrollment of the patient into an RPM system and (2) subsequent activation of RPM by the enrolled patient. We examined RPM enrollment and activation rates and the patient, physician, and institutional determinants of RPM use. Methods and Results— Information about the use of RPM-capable devices was obtained from the Boston Scientific Corporation ALTITUDE program and linked to the National Cardiovascular Data Registry ICD Registry. Patients were first categorized as RPM-enrolled and RPM-not enrolled, and the RPM-enrolled patients were further categorized into RPM-active and RPM-inactive groups based on whether they transmitted RPM data. Variables associated with RPM enrollment and activation were identified with the use of multivariable logistic regression. Among 39 158 patients with newly implanted RPM-capable devices, 62% (n=24 113) were RPM-enrolled. Of those enrolled, 76% (n=18 289, or 47% of the entire cohort) activated their device. RPM enrollment was highly variable among institutions. The hospital-specific median odds ratio for RPM enrollment was 3.43, signifying that physician or institutional factors are associated with RPM enrollment. In contrast, the hospital-specific median odds ratio for RPM activation was 1.69. Age, race, health insurance, geographic location, and health-related factors were similarly associated with both RPM enrollment and activation. Conclusions— RPM technology is used in less than half of eligible patients. Lack of enrollment into RPM systems is the major cause of underutilization, and this primarily relates to the local practice environment.

Use of Remote Monitoring Is Associated With Lower Risk of Adverse Outcomes Among Patients With Implanted Cardiac Defibrillators.

Background—We examined the association between the use of remote patient monitoring (RPM) of implantable cardioverter defibrillators (ICD) and all-cause mortality and rehospitalization among patients undergoing initial ICD implant. Methods and Results—A limited data set was constructed from Boston Scientific ALTITUDE Registry and National Cardiovascular Data Registry ICD Registry between January 2006 and March 2010. Vital status was determined using the Social Security Death Master File. All-cause mortality up to 3 years was compared in patients who used RPM with those who did not use RPM. Time-dependent frailty Cox models quantified the association between RPM use and all-cause mortality. Analyses were repeated in subgroups based on age, sex, race, ICD type, indication, and cardiomyopathy pathogenesis. Similar methodology examined the association between RPM use and all-cause rehospitalization in patients enrolled in Medicare fee-for-service patients ≥65 years. The study cohort (n=37 742, age 67±13, 72% male) had a 3-year mortality of 20.9% (median follow-up 832 days). In multivariable analyses, patients using RPM (n=22 023, 58%) had lower risk of mortality compared with those not using RPM (hazard ratio 0.67, 95% confidence interval 0.64–0.71, P<0.0001). The 3-year all-cause rehospitalization rate in the Medicare population (n=15 254) was 69.3% (median follow-up 922 days). Risk of rehospitalization of patients using RPM (n=9150, 60%) was lower than those not using RPM (hazard ratio 0.82, 95% confidence interval 0.80–0.84, P<0.0001). Findings were consistent across subgroups. Conclusions—Among patients undergoing initial ICD implant, RPM use is associated with significantly lower risk of adverse outcomes.

Cardiac Perforation From Implantable Cardioverter-Defibrillator Lead Placement Insights From the National Cardiovascular Data Registry

Background—Cardiac perforation is a feared complication of implantable cardioverter-defibrillator (ICD) lead implantation because of the potential for significant morbidity and mortality. Predictors of perforation and the severity of associated adverse events have not been well studied. We sought to identify predictors of cardiac perforation from ICD lead implantation and subsequent outcomes. Methods and Results—We studied 440 251 first-time ICD recipients in the ICD Registry implanted between January 2006 and September 2011. Using hierarchical multivariable logistic regression adjusting for patient, implanting physician, and hospital characteristics, we examined the predictors of perforation and the association of perforation with other major complications, length of stay, and in-hospital mortality. Cardiac perforation occurred in 625 patients (0.14%). After multivariable adjustment, older age, female sex, left bundle branch block, worsened heart failure class, higher left ventricular ejection fraction, and non–single-chamber ICD implant were associated with a greater odds of perforation. Conversely, atrial fibrillation, diabetes mellitus, previous cardiac bypass surgery, and higher implanter procedural volume were associated with a lower odds of perforation (all P<0.05). After adjustment, ICD recipients with perforation had greater odds of other associated major complications (odds ratio, 27.5; 95% confidence interval, 19.9–38.0; P<0.0001), postprocedural hospital stays >3 days (odds ratio, 16.3; 95% confidence interval, 13.7–19.4; P<0.0001), and in-hospital death (odds ratio, 17.7; 95% confidence interval, 12.2–25.6; P<0.0001). Conclusions—In a large population of ICD recipients, specific patient and implanter characteristics predicted cardiac perforation risk. Cardiac perforation was associated with a substantially increased risk of other major complications, prolonged hospital stays, and death.

Cardiac Resynchronization Therapy in Women Versus Men Observational Comparative Effectiveness Study From the National Cardiovascular Data Registry

Background—Women have been under-represented in trials of cardiac resynchronization therapy-defibrillators (CRT-D). Previous studies suggest that women benefit from CRT-D at shorter QRS duration than men and that there may be no benefit of CRT-D in patients without left bundle branch block (LBBB) regardless of patient sex. Methods and Results—We compared sex-specific death risk in 75 079 patients with New York Heart Association class III or IV heart failure, reduced left ventricular ejection fraction, and prolonged QRS duration (≥120 ms) receiving either CRT-D or implantable cardioverter defibrillator in subgroups according to QRS morphology and 10-ms increments in QRS duration. We applied propensity score weighting to control for differences between treatments. Among patients with LBBB, women receiving CRT-D had a lower relative death risk than those receiving an implantable cardioverter-defibrillator (absolute difference, 11%; hazard ratio=0.74 [95% confidence interval, 0.68–0.81]). In men, the lower mortality with CRT-D versus implantable cardioverter defibrillator was less pronounced (absolute difference, 9%; hazard ratio=0.84 [0.79–0.89]; sex×device interaction P=0.025). In those without LBBB, the mortality difference was modest and did not differ between women and men (absolute difference, 3%; hazard ratio=0.88 [0.79–0.97] in women and absolute difference, 2%; hazard ratio=0.95 [0.91–0.998] in men; interaction P=0.17). In subgroups according to QRS duration, CRT-D was associated with better survival in both sexes with LBBB and QRS ≥130 ms, whereas there was no clear relation between QRS duration and survival in patients without LBBB regardless of patient sex. Conclusions—In a large real-world population CRT-D was associated with a lower mortality risk in both sexes with LBBB, although more pronounced among women. Only among those with LBBB, both sexes had better survival with longer QRS duration. The mortality differences in patients without LBBB were attenuated in both sexes.

Place of Residence and Outcomes of Patients With Heart Failure Analysis From the Telemonitoring to Improve Heart Failure Outcomes Trial

Background—Recent studies show an association between neighborhood-level measures of socioeconomic status (SES) and outcomes for patients with heart failure. We do not know whether neighborhood SES has a primary effect or is a marker for individual SES. Methods and Results—We used the data from participants of the Telemonitoring to Improve Heart Failure Outcomes (Tele-HF) trial, recruited from 33 US internal medicine and cardiology practices and examined the association between neighborhood SES and outcomes of patients with heart failure. We used census tracts as proxies for neighborhoods and constructed summary SES scores that included information about wealth and income, education, and occupation. The primary end points were readmission and all-cause mortality at 6 months. We conducted patient interviews and medical chart reviews to obtain demographic information, clinical factors, therapies, and individual SES. We included 1557 patients: 524, 516, and 517 from low, medium, and high SES neighborhoods, respectively (mean age, 61.1±15.2 years; 42.2% women).Overall, 745 patients (47.8%) had ≥1 readmission and 179 patients (11.5%) died. When compared with patients in high SES neighborhoods, those living in low-SES neighborhoods were more likely to be readmitted (odds ratio, 1.35; 95% confidence interval, 1.01–1.82), but the mortality rates were not significantly different (odds ratio, 0.78; 95% confidence interval, 0.50–1.18). The results were consistent after multivariable adjustments for individual demographics, clinical factors, and individual SES. Conclusions—Among patients with heart failure, neighborhood SES was significantly associated with 6-month all-cause readmission even after adjusting for other patient-level factors, including individual SES. Greater number of events and longer follow-up is required to ascertain the potential effect of neighborhood SES on mortality. Clinical Trial Registration—URL: http://clinicaltrials.gov/. Unique identifier: NCT00303212.

Are Racial/Ethnic Gaps in the Use of Cardiac Resynchronization Therapy Narrowing? : An Analysis of 107,096 Patients From the National Cardiovascular Data Registry's ICD Registry

To the Editor: Chronic heart failure (HF) is a significant problem in the United States, affecting 5.7 million Americans. Studies have consistently demonstrated substantial racial and ethnic disparities in the use of guideline-recommended device therapies related to HF care. For example, although

Low Body Mass Index but Not Obesity Is Associated With In-Hospital Adverse Events and Mortality Among Implantable Cardioverter-Defibrillator Recipients: Insights From the National Cardiovascular Data Registry

Background Implantable cardioverter-defibrillators (ICDs) are placed in patients at risk for sudden cardiac death, but the procedure may cause adverse events. Patient body habitus may be an important factor responsible for ICD implantation complications. We assessed whether underweight or obese compared with normal weight patients, as defined by body mass index (BMI), were at increased risk for adverse events from ICD implantation. Methods and Results We studied 83 312 first-time ICD recipients in the National Cardiovascular Data Registry-ICD Registry implanted between April 2010 and June 2011. Using hierarchical multivariable logistic regression adjusted for patient demographic and clinical characteristics, we examined the association of BMI with in-hospital complications, length of hospital stay, and mortality. Underweight (BMI ≤18.5 kg/m2) patients comprised 1.7% of the cohort (n=1434), whereas obese (BMI≥30 kg/m2) patients comprised 40.1% (n=33 339). Overall, a higher proportion of underweight patients experienced complications (normal weight, 2.3%; obese, 2.1%; underweight 5.2%; P<0.0001) and death (normal weight, 0.3%; obese, 0.3%; underweight 0.8%; P=0.026) as a result of ICD implantation. After multivariable adjustment, underweight ICD recipients had a greater odds of complications (odds ratio [OR], 2.15; 95% confidence interval [CI], 1.68 to 2.75; P<0.0001), hospital stay >3 days (OR, 1.62; 95% CI, 1.38 to 1.89; P<0.0001), and in-hospital death (OR, 2.27; 95% CI, 1.21 to 4.27; P=0.011) compared with normal weight patients. Obese patients did not exhibit any meaningful differences in the same outcomes. Conclusions In a large, real-world population, underweight first-time ICD recipients experienced significantly more periprocedural complications, prolonged hospital stays, and in-hospital death compared with normal weight patients.

Association Between a Prolonged PR Interval and Outcomes of Cardiac Resynchronization Therapy: A Report From the National Cardiovascular Data Registry.

Background: A prolonged PR interval is common among cardiac resynchronization therapy (CRT) candidates; however, the association between PR interval and outcomes is unclear, and the data are conflicting. Methods: We conducted inverse probability weighted analyses of 26 451 CRT-eligible (ejection fraction ⩽35, QRS ≥120 ms) patients from the National Cardiovascular Data Registry ICD Registry to assess the association between a prolonged PR interval (≥230 ms), receipt of CRT with defibrillator (CRT-D) versus implantable cardioverter defibrillator (ICD), and outcomes. We first tested the association between a prolonged PR interval and outcomes among patients stratified by device type. Next, we performed a comparative effectiveness analysis of CRT-D versus ICD among patients when stratified by PR interval. Using Medicare claims data, we followed up with patients up to 5 years for incident heart failure hospitalization or death. Results: Patients with a PR≥230 ms (15%; n=4035) were older and had more comorbidities, including coronary artery disease, atrial arrhythmias, diabetes mellitus, and chronic kidney disease. After risk adjustment, a PR≥230 ms (versus PR<230 ms) was associated with increased risk of heart failure hospitalization or death among CRT-D (hazard ratio, 1.23; 95% confidence interval, 1.14–1.31; P<0.001) but not ICD recipients (hazard ratio, 1.08; 95% confidence interval, 0.97–1.20; P=0.17) (Pinteraction=0.043). CRT-D (versus ICD) was associated with lower rates of heart failure hospitalization or death among patients with PR<230 ms (hazard ratio, 0.79; 95% confidence interval, 0.73–0.85; P<0.001) but not PR≥230 ms (hazard ratio, 1.01; 95% confidence interval, 0.87–1.17; P=0.90) (Pinteraction=0.0025). Conclusions: A PR≥230 ms is associated with increased rates of heart failure hospitalization or death among CRT-D patients. The real-world comparative effectiveness of CRT-D (versus ICD) is significantly less among patients with a PR≥230 ms in comparison with patients with a PR<230 ms.Background: A prolonged PR interval is common among cardiac resynchronization therapy (CRT) candidates; however, the association between PR interval and outcomes is unclear, and the data are conflicting. Methods: We conducted inverse probability weighted analyses of 26 451 CRT-eligible (ejection fraction ≤35, QRS ≥120 ms) patients from the National Cardiovascular Data Registry ICD Registry to assess the association between a prolonged PR interval (≥230 ms), receipt of CRT with defibrillator (CRT-D) versus implantable cardioverter defibrillator (ICD), and outcomes. We first tested the association between a prolonged PR interval and outcomes among patients stratified by device type. Next, we performed a comparative effectiveness analysis of CRT-D versus ICD among patients when stratified by PR interval. Using Medicare claims data, we followed up with patients up to 5 years for incident heart failure hospitalization or death. Results: Patients with a PR≥230 ms (15%; n=4035) were older and had more comorbidities, including coronary artery disease, atrial arrhythmias, diabetes mellitus, and chronic kidney disease. After risk adjustment, a PR≥230 ms (versus PR<230 ms) was associated with increased risk of heart failure hospitalization or death among CRT-D (hazard ratio, 1.23; 95% confidence interval, 1.14–1.31; P <0.001) but not ICD recipients (hazard ratio, 1.08; 95% confidence interval, 0.97–1.20; P =0.17) ( P interaction=0.043). CRT-D (versus ICD) was associated with lower rates of heart failure hospitalization or death among patients with PR<230 ms (hazard ratio, 0.79; 95% confidence interval, 0.73–0.85; P <0.001) but not PR≥230 ms (hazard ratio, 1.01; 95% confidence interval, 0.87–1.17; P =0.90) ( P interaction=0.0025). Conclusions: A PR≥230 ms is associated with increased rates of heart failure hospitalization or death among CRT-D patients. The real-world comparative effectiveness of CRT-D (versus ICD) is significantly less among patients with a PR≥230 ms in comparison with patients with a PR<230 ms. # Clinical Perspective {#article-title-32}