Analysis of Temporal Trends and Variation in the Use of Defibrillation Testing in Contemporary Practice.

Importance: Defibrillation testing (DFT) is performed during implantable cardioverter-defibrillator (ICD) implantation to assess the capacity of the device to detect and terminate ventricular arrhythmias. However, DFT can result in complications and omission of its use has been shown to be safe. Objective: To describe temporal trends and variation in the use of DFT in contemporary practice in the United States. Design, Setting, and Participants: This multicenter cross-sectional study used data from the National Cardiovascular Data Registry ICD Registry. A total of 499 211 patients from 1794 different facilities undergoing first-time ICD implantation from April 2010 to December 2015 were included. Data analysis was performed from May 20, 2015, to August 15, 2019. Exposure: Defibrillation testing was assessed using the National Cardiovascular Data Registry ICD Registry. Main Outcomes and Measures: Defibrillation testing rates and median odds ratios (MORs) were assessed over time. The MOR represents the odds that a randomly selected patient receiving testing at a hospital with high testing rates would be tested compared with if he or she had received care at a hospital with low testing rates. Results: Of the 499 211 patients from 1794 different facilities included in this analysis, the mean (SD) age of the population was 65.5 (13.4) years and 356 681 patients (71.4%) were men. The use of DFT declined from 71.6% in the first calendar quarter of 2010 to 36.4% in the fourth quarter of 2015 (P < .001). Patients undergoing DFT were more likely than those without testing to have ischemic heart disease (170 569 [58.1%] vs 116 295 [56.6%]), ventricular tachycardia (91 500 [31.2%] vs 58 949 [28.7%]), and less advanced heart failure (New York Heart Association class I and II, 153 188 [52.2%] vs 91 215 [44.4%]) (P < .001 for all). The MOR for the use of defibrillation testing was 3.78 (95% CI, 3.54-4.03) in 2010, increasing to 6.05 (95% CI, 5.61-6.52) in 2015, indicating that by 2015 a randomly selected patient receiving testing at a hospital with high testing rates would have a 6-fold higher odds of being tested than if they had received care at a hospital with low testing rates. Conclusions and Relevance: Defibrillation testing at the time of ICD placement in the United States may have declined over time; however, institutional variation in its use appears to be marked and increased. This variability in the reduced use of defibrillation testing could reflect differences in individual or institutional cultures of practice.

Timing of cardiac resynchronization therapy device implantation in heart failure patients and its association with outcomes.

BACKGROUND: When used in appropriately selected heart failure (HF) patients, cardiac resynchronization therapy (CRT) reduces mortality and hospitalization. It is not understood whether CRT implantation during hospitalization for HF is associated with similar benefits. HYPOTHESIS: Timing of CRT implantation relative to hospitalization for HF is associated with clinical outcomes. METHODS: This analysis included patients eligible for CRT and discharged alive between January 2005 and December 2012 from 388 hospitals in Get With The Guidelines-HF. Participants were linked with Centers for Medicare and Medicaid Services data to evaluate outcomes of all-cause mortality and HF re-hospitalization based on CRT status (present on admission, placed during hospitalization, and prescribed at discharge; reference = no CRT). RESULTS: Of 15 619 CRT-eligible HF patients, 2408 (15%) had CRT on admission, 1269 (8%) underwent CRT implantation during hospitalization and 643 (4%) had CRT prescribed at discharge. Compared with patients without CRT, mortality was lower in those who received CRT implantation during HF hospitalization (adjusted hazard ratio [HR] 0.63; P < 0.0001) and those prescribed CRT at discharge (adjusted HR 0.78; P = 0.048). A reduction in HF re-hospitalization was observed in patients with CRT implanted during hospitalization (adjusted HR 0.64; P < 0.0001), but not in those who were prescribed CRT at discharge (adjusted HR 1.02; P = 0.77). CONCLUSION: CRT implantation during HF hospitalization was associated with lower rates of mortality and HF re-hospitalization. These data suggest that a CRT utilization strategy that does not delay implantation to the post-discharge period may be appropriate. Randomized data are needed to definitively identify optimal timing of CRT implantation.

Relation of Early Repolarization (J Point Elevation) to Mortality in Blacks (from the Jackson Heart Study).

Conflicting data exist regarding the associations of early repolarization (ER) with electrocardiogram (ECG) and clinical outcomes in blacks. We examined the association of ER defined by J point elevation (JPE) and all-cause mortality, and heart failure (HF) hospitalization in blacks in the Jackson Heart Study (JHS) cohort. We included JHS participants with ECGs from the baseline visit coding JPE and excluded participants with paced rhythms or QRS duration ≥120 ms. We compared the cumulative incidence of 10-year all-cause mortality and 8-year HF hospitalization by presence of JPE ≥0.1 mV in any ECG lead at baseline using Kaplan-Meier estimates and multivariable Cox models. Of the 4,978 participants, 1,410 (28%) had JPE at baseline: anterior leads 97.8%, lateral leads 8.3%, and inferior leads 2.9%. Compared with participants without JPE, those with JPE were younger, more likely to be male and current smokers, and less likely to have hypertension. Over a median follow-up of 8 years, there were no significant differences in the cumulative incidence or multivariable-adjusted hazards of all-cause mortality or HF hospitalization in participants with and without JPE in any lead (adjusted hazard ratio 0.97, 95% confidence interval 0.89 to 1.52, and adjusted hazard ratio 1.18, 95% confidence interval 0.9 to 1.54, respectively). Of the 2,523 participants who completed Exam 3 without JPE at baseline, 246 (10%) developed JPE over follow-up. In conclusion, JPE on ECG was not associated with long-term mortality or HF hospitalization in a large prospective black community cohort, suggesting that ER may represent a benign ECG finding in blacks.

Usefulness and Cost-Effectiveness of Universal Echocardiographic Contrast to Detect Left Ventricular Thrombus in Patients with Heart Failure and Reduced Ejection Fraction.

Contrast is a recommended but frequently unused tool in transthoracic echocardiography to improve detection of left ventricular thrombus in patients with ejection fraction (EF) ≤35%. The clinical and economic outcomes of a possible solution (i.e., universal contrast use) remain uncertain. To estimate clinical benefit, cost, and cost-effectiveness of a diagnostic strategy of universal use of contrast (vs no contrast) during echocardiography in patients with reduced EF, we created a decision analytic model using echocardiography sensitivity and specificity for left ventricular thrombus detection from a meta-analysis, as well as survival and cost estimates from published literature. Universal contrast use (vs nonuse) did not result in clinical or statistical improvement in estimated life years (8.509 vs 8.504) or quality-adjusted life years (5.620 vs 5.616). The cost of contrast was offset by reductions in subsequent health-care costs, resulting in similar total costs ($201,569 vs $201,573). In conclusion, although an intuitively attractive practice improvement strategy, universal contrast use strategy appears to offer no appreciable benefit to quality-adjusted survival or financial outcomes in patients with low EF.

Representation of black patients in randomized clinical trials of heart failure with reduced ejection fraction.

BACKGROUND: Black individuals have a disproportionately higher burden of heart failure with reduced ejection fraction (HFrEF) relative to other racial and ethnic populations. We conducted a systematic review to determine the representation, enrollment trends, and outcomes of black patients in historic and contemporary randomized clinical trials (RCTs) for HFrEF. METHODS: We searched PubMed and Embase for RCTs of patients with chronic HFrEF that evaluated therapies that significantly improved clinical outcomes. We extracted trial characteristics and compared them by trial type. Linear regression was used to assess trends in enrollment among HFrEF RCTs over time. RESULTS: A total of 25 RCTs, 19 for pharmacotherapies and 6 (n=9,501) for implantable cardioverter defibrillators, were included in this analysis. Among these studies, there were 78,816 patients, 4,640 black (5.9%), and the median black participation per trial was 162 patients. Black race was reported in the manuscript of 14 (56.0%) trials, and outcomes by race were available for 12 (48.0%) trials. Implantable cardiac defibrillator trials enrolled a greater percentage of black patients than pharmacotherapy trials (7.1% vs 5.7%). Overall, patient enrollment among the 25 RCTs increased over time (P = .075); however, the percentage of black patients has decreased (P = .001). Outcomes varied significantly between black and white patients in 6 studies. CONCLUSIONS: Black patients are modestly represented among pivotal RCTs of individuals with HFrEF for both pharmacotherapies and implantable cardioverter defibrillators. The current trend for decreasing black representation in trials of HF therapeutics is concerning and must improve to ensure the generalizability for this vulnerable population.

Utilization of cardiac resynchronization therapy in eligible patients hospitalized for heart failure and its association with patient outcomes.

OBJECTIVES: We examined trends in CRT utilization overall and by sex and race and to assess whether CRT use is associated with a reduction in HF hospitalization and mortality. BACKGROUND: It is unknown whether underutilization and race/sex-based differences in cardiac resynchronization therapy (CRT) use have persisted. The association between CRT and heart failure (HF) hospitalization and mortality in real-world practice remains unclear. METHODS: We linked 72,008 HF patients from 388 hospitals participating in Get With The Guidelines HF eligible for CRT with Centers for Medicare & Medicaid Services data to assess CRT utilization trends, HF hospitalization rates, and all-cause mortality. RESULTS: From 2005-2014, 18,935 (26.3%) eligible patients had CRT in place, implanted, or prescribed. The majority were male (60.0%) and white (61.9%). CRT utilization increased during the study period (P = .0002) especially in the early period. Women were less likely to receive CRT, and this difference increased over time (interaction P = .0037) despite greater mortality risk reduction (interaction P = .0043). Black patients were less likely than white patients to have CRT throughout the study period (adjusted hazard ratio (HR) 0.79; 95% CI 0.74-0.85). Patients with CRT implanted during the index hospitalization had lower mortality (adjusted HR 0.65; 95% CI 0.59-0.71) and were less likely to be readmitted for HF than patients without CRT (adjusted HR 0.64; 95% CI 0.58-0.71). CONCLUSIONS/RELEVANCE: CRT use has increased in all populations, but it remains underutilized. CRT remains more common among white than black HF patients, and women were less likely than men to receive CRT despite deriving greater benefit.

Race and Sex Differences in QRS Interval and Associated Outcome Among Patients with Left Ventricular Systolic Dysfunction.

BACKGROUND: Prolonged QRS duration is associated with increased mortality among heart failure patients, but race or sex differences in QRS duration and associated effect on outcomes are unknown. METHODS AND RESULTS: We investigated QRS duration and morphology among 2463 black and white patients with heart failure and left ventricular ejection fraction ≤35% who underwent coronary angiography and 12-lead electrocardiography at Duke University Hospital from 1995 through 2011. We used multivariable Cox regression models to assess the relationship between QRS duration and all-cause mortality and investigate race-QRS and sex-QRS duration interaction. Median QRS duration was 105 ms (interquartile range [IQR], 92-132) with variation by race and sex (P<0.001). QRS duration was longest in white men (111 ms; IQR, 98-139) followed by white women (108 ms; IQR, 92-140), black men (100 ms; IQR, 91-120), and black women (94 ms; IQR, 86-118). Left bundle branch block was more common in women than men (24% vs 14%) and in white (21%) versus black individuals (12%). In black patients, there was a 16% increase in risk of mortality for every 10 ms increase in QRS duration up to 112 ms (hazard ratio, 1.16; 95% CI, 1.07, 1.25) that was not present among white patients (interaction, P=0.06). CONCLUSIONS: Black individuals with heart failure had a shorter QRS duration and more often had non-left bundle branch block morphology than white patients. Women had left bundle branch block more commonly than men. Among black patients, modest QRS prolongation was associated with increased mortality.

Associations Between Blood Pressure and Outcomes Among Blacks in the Jackson Heart Study.

BACKGROUND: In 2014, new hypertension guidelines liberalized blood pressure goals for persons 60 years and older. Little is known about the implications for blacks. METHODS AND RESULTS: Using data from 2000 through 2011 for 5280 participants in the Jackson Heart Study, a community-based black cohort in Jackson, Mississippi, we examined whether higher blood pressure was associated with greater risk of mortality and heart failure hospitalization, and whether the risk was the same across age groups. We investigated associations between baseline blood pressure and both mortality and heart failure hospitalization. We also tested for interactions between age and blood pressure in the mortality model. Median systolic and diastolic blood pressures at baseline were 125 mm Hg (25th-75th percentile, 114-137 mm Hg) and 79 mm Hg (72-86 mm Hg), respectively. Median follow-up was 9 years for mortality and 7 years for heart failure hospitalization. After multivariable adjustment, every 10 mm Hg increase in systolic blood pressure was associated with greater risks of mortality (hazard ratio, 1.12; 95% CI, 1.06-1.17) and heart failure hospitalization (1.07; 95% CI, 1.00-1.14). The mortality risk per 10 mm Hg increase in systolic blood pressure was greater in participants younger than 60 years (1.26; 95% CI, 1.13-1.42) than among participants 60 years and older (1.09; 95% CI, 1.03-1.15). CONCLUSIONS: Adults in all age groups were at greater risk of mortality as systolic blood pressure increased. In the context of the 2014 hypertension guidelines, these findings should be considered when determining treatment goals in black patients.

Patient factors associated with quality of life in atrial fibrillation.

BACKGROUND: As treatment options for atrial fibrillation (AF) increase, more attention is focused on patients' experiences and quality of life (QoL). However, little is known about the factors associated with these outcomes. METHODS: The Atrial Fibrillation Effect on QualiTy-of-life (AFEQT) is a disease-specific QoL tool for AF, with domain and summary scores ranging from 0 (the worst QoL) to 100. Using multivariable linear regression, we evaluated factors associated with baseline AFEQT Summary and Subscale Scores in ORBIT AF, a large, community-based AF registry. Independent associations were reported as coefficient estimates in scores and 95% confidence intervals (CI). RESULTS: Overall, AFEQT was assessed in 2007 AF outpatients from 99 sites. Median age (IQR) was 76 years (67-82) and 43% were female. The median AFEQT summary score was 82 (67-94). Female sex, younger age, new onset AF, higher heart rate, obstructive sleep apnea, symptomatic heart failure (HF), chronic obstructive pulmonary disease and coronary artery disease were all independently associated with reduced QoL. Female sex [Estimate -7.03, 95% CI (-9.31, -4.75)] and new onset versus permanent AF [Estimate -7.44, 95% CI (-11.03, -3.84)] were independently associated with increased symptoms. NYHA Class III or IV HF [Estimate -14.44, 95% CI (-19.46, -8.76)] and female sex [Estimate -7.91, 95% CI (-9.95, -5.88)] were most independently associated with impaired daily activities. CONCLUSIONS: QoL in patients with AF varies widely and is associated with several patient factors. Understanding patient factors independently associated with worse QoL can be a foundation for tailoring treatment.

Ventricular conduction and long-term heart failure outcomes and mortality in African Americans: insights from the Jackson Heart Study.

BACKGROUND: QRS prolongation is associated with adverse outcomes in mostly white populations, but its clinical significance is not well established for other groups. We investigated the association between QRS duration and mortality in African Americans. METHODS AND RESULTS: We analyzed data from 5146 African Americans in the Jackson Heart Study stratified by QRS duration on baseline 12-lead ECG. We defined QRS prolongation as QRS≥100 ms. We assessed the association between QRS duration and all-cause mortality using Cox proportional hazards models and reported the cumulative incidence of heart failure hospitalization. We identified factors associated with the development of QRS prolongation in patients with normal baseline QRS. At baseline, 30% (n=1528) of participants had QRS prolongation. The cumulative incidences of mortality and heart failure hospitalization were greater with versus without baseline QRS prolongation: 12.6% (95% confidence interval [CI], 11.0-14.4) versus 7.1% (95% CI, 6.3-8.0) and 8.2% (95% CI, 6.9-9.7) versus 4.4% (95% CI, 3.7-5.1), respectively. After risk adjustment, QRS prolongation was associated with increased mortality (hazard ratio, 1.27; 95% CI, 1.03-1.56; P=0.02). There was a linear relationship between QRS duration and mortality (hazard ratio per 10 ms increase, 1.06; 95% CI, 1.01-1.12). Older age, male sex, prior myocardial infarction, lower ejection fraction, left ventricular hypertrophy, and left ventricular dilatation were associated with the development of QRS prolongation. CONCLUSIONS: QRS prolongation in African Americans was associated with increased mortality and heart failure hospitalization. Factors associated with developing QRS prolongation included age, male sex, prior myocardial infarction, and left ventricular structural abnormalities.

Optimal utilization and management of implanted cardiac rhythm devices in patients hospitalized for heart failure.

Improved utilization and optimization of device therapy in the management of patients with decompensated heart failure (HF) is an important clinical priority. Diagnostic cardiac rhythm device data have been shown to predict hospitalization for HF. Cardiac resynchronization therapy is a highly effective therapy for the prevention of HF hospitalization. Evaluation and optimization of cardiac resynchronization therapy should be considered in all patients admitted with HF despite cardiac resynchronization therapy.