High- versus low-gradient aortic stenosis: Is our evaluation limited by aorto-mitral angle on cardiovascular CT?

BACKGROUND: Accurate assessment of aortic valve (AV) stenosis (AS) on transthoracic echocardiogram is crucial for appropriate clinical management. However, discordance between aortic valve area (AVA) and Doppler can complicate the diagnosis of severe AS in low-gradient (LG) AS phenotypes. METHODS: We reviewed 220 consecutive patients with suspected severe AS and AVA ≤1.0 cm2 on transthoracic echocardiogram who were evaluated for transcatheter AV replacement (TAVR) within a large health system from 2015 to 2019. We compared AV calcium score and aorto-mitral angle (AMA) on 3-chamber views from ECG-gated cardiovascular CT among patients with high-gradient (HG) AS (N = 19), paradoxical low-flow low-gradient (PLFLG) AS (N = 24) and normal-flow low-gradient (NFLG) AS (N = 14). RESULTS: All groups had comparable age, comorbidities, and AV calcium scores. Compared to patients with HG AS (mean AMA 120 ± 10°), those with PLFLG AS (104 ± 12°; p < 0.001) and NFLG AS (106 ± 13°; p = 0.008) had narrower mean AMA values on cardiovascular CT. CONCLUSION: LG AS patients have significantly narrower AMA than HG AS patients on cardiovascular CT. Due to difficulty obtaining parallel Doppler alignment, narrower AMA may contribute to AVA-Doppler discordance on echocardiogram. These findings emphasize the need for additional information in the setting of LG AS.

Implementing Formal Mitral Heart Team Improves Multidisciplinary Evaluation Rate and Survival of Patients With Severe Primary Mitral Regurgitation.

BACKGROUND: Multidisciplinary heart team (HT) evaluation is recommended for patients with severe primary mitral regurgitation to optimize treatment decisions. However, its impact on patient outcomes remains unknown. We evaluated the impact of implementing mitral HT on patient survival. METHODS AND RESULTS: We conducted a retrospective cohort study of patients with new diagnoses of severe primary mitral regurgitation in a large healthcare network echocardiogram database between 2016 and 2020. We compared the incidence of multidisciplinary evaluation by structural cardiology and cardiac surgery services and 2-year survival before and after mitral HT implementation. The 1:1 propensity-score matching between pre- and post-mitral HT used Society of Thoracic Surgeons Predicted Risk of Mortality for mitral repair, age, sex, race, heart failure symptoms, inpatient setting, history of MI, and dementia as covariates. Logistic regression identified variables associated with the likelihood of undergoing multidisciplinary evaluation. Among 70 510 echocardiograms performed, 391 patients had severe primary mitral regurgitation (median age, 77 years; 46% women). Multidisciplinary evaluation increased from 29% to 89% (P<0.001), and intervention increased from 24% to 75% following mitral HT implementation (P<0.001). Among 180 propensity-score matched patients, mortality was lower post-mitral HT at 2 years (19% versus 32%, P=0.04). The multivariable model showed that mitral HT implementation and heart failure symptoms were associated with higher odds of undergoing multidisciplinary evaluation (OR [odds ratio], 18.7 and 2.72, respectively), whereas female sex and older age were associated with lower odds (OR, 0.39 and 0.93, respectively). CONCLUSIONS: Implementation of mitral HT was associated with drastic improvement in multidisciplinary evaluation for patients with severe primary mitral regurgitation. This coincided with higher proportions of patients undergoing mechanical correction of MR and improved overall patient survival.

Factors associated with reporting left ventricular ejection fraction with 3D echocardiography in real-world practice.

BACKGROUND: Guidelines recommend 3D echocardiography (3DE) to assess left ventricular ejection fraction (LVEF) on transthoracic echocardiogram (TTE) when possible, but it is unclear which factors are most strongly associated with reporting 3DE LVEF in real-world practice. METHODS: We evaluated 3DE LVEF reporting by age, sex, BMI, TTE location and variation in reporting by sonographer and reader. All TTEs were performed without contrast enhancement agent at a large medical center from 9/2015 to 12/2020 using ultrasound machines capable of 3DE. We used multivariable logistic regression to assess which factors were most associated with reporting 3DE LVEF. RESULTS: Among 35 641 TTEs included in this study, 57.4% were performed on women. 3DE LVEF was reported on 18 391 TTEs (51.6% of cohort; 50.5% for women and 52.4% for men). Portable inpatient TTEs (n = 5569) had the lowest rates of 3DE LVEF reporting (30.9%), while general outpatient TTEs (n = 15 933) had greater reporting (56.9%). Outpatient TTEs with an indication for chemotherapy (n = 3244) had the highest rates of 3DE LVEF (87.2%). The median (IQR) percentage of TTEs reporting 3D LVEF was 52.7% (43.1%-68.1%) among sonographers and 51.6% (46.5%-59.6%) among readers. Among 20082 (56.3%) TTEs with 3DE LVEF measured by sonographers, 91.6% were included by readers in the final report. After adjustment, performing sonographer in the highest reporting quartile was most strongly associated with reporting 3DE LVEF (OR 7.04, 95% CI 6.55-7.56), while an inpatient portable study had the strongest negative association for reporting (OR .38, 95% CI .35-.40). CONCLUSIONS: Use of 3DE LVEF in real-world practice varies substantially based on performing sonographer and is low for hospitalized patients, but can be frequently used for chemotherapy. Initiatives are needed to increase sonographer 3DE acquisition in most clinical settings.

Myocardial Injury on CMR in Patients With COVID-19 and Suspected Cardiac Involvement.

BACKGROUND: Myocardial injury in patients with COVID-19 and suspected cardiac involvement is not well understood. OBJECTIVES: The purpose of this study was to characterize myocardial injury in a multicenter cohort of patients with COVID-19 and suspected cardiac involvement referred for cardiac magnetic resonance (CMR). METHODS: This retrospective study consisted of 1,047 patients from 18 international sites with polymerase chain reaction-confirmed COVID-19 infection who underwent CMR. Myocardial injury was characterized as acute myocarditis, nonacute/nonischemic, acute ischemic, and nonacute/ischemic patterns on CMR. RESULTS: In this cohort, 20.9% of patients had nonischemic injury patterns (acute myocarditis: 7.9%; nonacute/nonischemic: 13.0%), and 6.7% of patients had ischemic injury patterns (acute ischemic: 1.9%; nonacute/ischemic: 4.8%). In a univariate analysis, variables associated with acute myocarditis patterns included chest discomfort (OR: 2.00; 95% CI: 1.17-3.40, P = 0.01), abnormal electrocardiogram (ECG) (OR: 1.90; 95% CI: 1.12-3.23; P = 0.02), natriuretic peptide elevation (OR: 2.99; 95% CI: 1.60-5.58; P = 0.0006), and troponin elevation (OR: 4.21; 95% CI: 2.41-7.36; P < 0.0001). Variables associated with acute ischemic patterns included chest discomfort (OR: 3.14; 95% CI: 1.04-9.49; P = 0.04), abnormal ECG (OR: 4.06; 95% CI: 1.10-14.92; P = 0.04), known coronary disease (OR: 33.30; 95% CI: 4.04-274.53; P = 0.001), hospitalization (OR: 4.98; 95% CI: 1.55-16.05; P = 0.007), natriuretic peptide elevation (OR: 4.19; 95% CI: 1.30-13.51; P = 0.02), and troponin elevation (OR: 25.27; 95% CI: 5.55-115.03; P < 0.0001). In a multivariate analysis, troponin elevation was strongly associated with acute myocarditis patterns (OR: 4.98; 95% CI: 1.76-14.05; P = 0.003). CONCLUSIONS: In this multicenter study of patients with COVID-19 with clinical suspicion for cardiac involvement referred for CMR, nonischemic and ischemic patterns were frequent when cardiac symptoms, ECG abnormalities, and cardiac biomarker elevations were present.

Thirty-Day and 90-Day Episode of Care Spending Following Heart Failure Hospitalization Among Medicare Beneficiaries.

BACKGROUND: Despite growing interest in value-based models, utilization patterns and costs for heart failure (HF) admissions are not well understood. We sought to characterize Medicare spending for patients with HF for 30- and 90-day episodes of care (which include an index hospitalization and 30 or 90 days following discharge) and to describe the patterns of post-acute care spending. METHODS: Using Medicare fee-for-service administrative claims data from 2016 to 2018, we performed a retrospective analysis of patients discharged after hospitalization with primary discharge diagnoses of systolic HF, diastolic HF, hypertensive heart disease (HHD) with HF, and HHD with HF and chronic kidney disease. We analyzed coding patterns across these groups over time, median 30- and 90-day payments, and costs allocated to index hospitalization and postacute care. RESULTS: The study included 935 962 patients discharged following hospitalization for HF (systolic HF: 178 603; diastolic HF: 165 156; HHD with HF: 226 929; HHD with HF and chronic kidney disease: 365 274). The proportion of HHD codes increased from 26% of HF hospitalizations in 2016 to 91% in 2018. There was substantial spending on 30-day (median $13 330, interquartile range $9912-$22 489) and 90-day episodes (median $21 658, interquartile range $12 423-$37 630) for HF with significant variation, such that the third quartile of patients incurred costs 3 times the amount of the first quartile. Across all codes, the index hospitalization accounted for ≈70% of 30-day and 45% of 90-day spending. Sixty-one percent of postacute care spending occurred 31 to 90 days following discharge, with readmissions and observation stays (36%) and skilled nursing facilities (27%) comprising the largest categories. CONCLUSIONS: This patient episode-level analysis of contemporary Medicare beneficiaries is the first to examine 90-day spending, which will become an increasingly important pasyment benchmark with the expansion of the Medicare Bundled Payments for Care Improvement Program. Further investigation into the drivers of costs will be essential to provide high-value HF care.

Comfort Measures Only in Myocardial Infarction: Prevalence of This Status, Change Over Time, and Predictors From a Nationwide Study.

BACKGROUND: Patients hospitalized with acute myocardial infarction (AMI) have a high mortality rate. Despite increasing recognition of the role for comfort focused care, little is known about the prevalence of comfort measures only (CMO) care among patients with AMI. The objective of this study was to investigate patient- and hospital-level patterns and predictors of CMO care among patients admitted with AMI. METHODS: This retrospective cohort study used the National Cardiovascular Data Registry Chest Pain-MI Registry, which contains data on patients admitted with AMI. Data were analyzed in 6-month increments from January 2015 to June 2018. RESULTS: Among 483 696 patients with AMI across 827 hospitals, 13 955 (2.9%) had CMO status at discharge (2.6% non-ST-segment-elevation myocardial infarction and 3.4% ST-segment-elevation myocardial infarction). There was a modest decline in CMO rates over time (3.0% to 2.8%). Independent patient characteristics associated with CMO status included male gender, White race, nonprivate insurance, frailty, and higher estimated bleeding and mortality risks. There was substantial variation in CMO rates across hospitals, with the proportion of CMO patients ranging from 0% to 17.1% and a median odds ratio of 1.59 (95% CI, 1.56-1.62). Among the 13 955 patients who were CMO by discharge, 8134 (58.3%) underwent diagnostic catheterization. This is despite significantly elevated risks predicted using precatheterization models, specifically the ACTION Registry GWTG in-hospital major bleeding and mortality risk scores. Patients who were initially managed invasively but later made CMO experienced high rates of procedural complications, including cardiogenic shock (38.3%), dialysis (10.1%), and bleeding (33.3%). CONCLUSIONS: Most patients with AMI who were CMO by discharge had aggressive initial management and became CMO following in-hospital complications of their care. Early identification of high-risk patients and appropriate transition of such patients to CMO, if aligned with their values, remain important areas for future quality programs in AMI.

Trends in transcatheter and surgical aortic valve replacement in the United States, 2008-2018.

We conducted a retrospective study using the NIS database from 2008 to 2018 to examine the most contemporary national hospitalization trends of transcatheter (TAVR) and surgical (SAVR) aortic valve replacement regarding volume, patient and hospital demographics and economics, resource utilization, total cost of stay, and in-hospital mortality. We demonstrate that TAVR procedures have been performed on a slow by steadily diversifying patient population while volume has grown significantly, while in-hospital mortality, length of stay, discharge home, and costs have improved, whereas these metrics have generally remained stable for SAVR. These trends will likely drive continued TAVR adoption, greatly expanding the overall aortic stenosis patient population eligible for AVR.

Trends in Heart Failure Hospitalizations in the US from 2008 to 2018.

BACKGROUND: Heart failure (HF) is a major driver of health care costs in the United States and is increasing in prevalence. There is a paucity of contemporary data examining trends among hospitalizations for HF that specifically compare HF with reduced or preserved ejection fraction (HFrEF or HFpEF, respectively). METHODS AND RESULTS: Using the National Inpatient Sample, we identified 11,692,995 hospitalizations due to HF. Hospitalizations increased from 1,060,540 in 2008 to 1,270,360 in 2018. Over time, the median age of patients hospitalized because of HF decreased from 76.0 to 73.0 years (P < 0.001). There were increases in the proportions of Black patients (18.4% in 2008 to 21.2% in 2018) and of Hispanic patients (7.1% in 2008 to 9.0% in 2018; P < 0.001, all). Over the study period, we saw an increase in comorbid diabetes, sleep apnea and obesity (P < 0.001, all) in the entire cohort with HF as well as in the HFrEF and HFpEF subgroups. Persons admitted because of HFpEF were more likely to be white and older compared to admissions because of HFrEF and also had lower costs. Inpatient mortality decreased from 2008 to 2018 for overall HF (3.3% to 2.6%) and HFpEF (2.4% to 2.1%; P < 0.001, all) but was stable for HFrEF (2.8%, both years). Hospital costs, adjusted for inflation, decreased in all 3 groups across the study period, whereas length of stay was relatively stable over time for all groups. CONCLUSIONS: The volume of patients hospitalized due to HF has increased over time and across subgroups of ejection fraction. The demographics of HF, HFrEF and HFpEF have become more diverse over time, and hospital inpatient costs have decreased, regardless of HF type. Inpatient mortality rates improved for overall HF and HFpEF admissions but remained stable for HFrEF admissions.

Trends and Outcomes of Cardiac Transplantation in the Lowest Urgency Candidates.

Background Because of discrepancies between donor supply and recipient demand, the cardiac transplantation process aims to prioritize the most medically urgent patients. It remains unknown how recipients with the lowest medical urgency compare to others in the allocation process. We aimed to examine differences in clinical characteristics, organ allocation patterns, and outcomes between cardiac transplantation candidates with the lowest and highest medical urgency. Methods and Results We performed a retrospective analysis of the United Network for Organ Sharing database. Patients listed for cardiac transplantation between January 2011 and May 2020 were stratified according to status at time of transplantation. Baseline recipient and donor characteristics, waitlist survival, and posttransplantation outcomes were compared in the years before and after the 2018 allocation system change. Lower urgency patients in the old system were older (58.5 versus 56 years) and more likely female (54.4% versus 23.8%) compared with the highest urgency patients, and these trends persisted in the new system (P<0.001, all). Donors for the lowest urgency patients were more likely older, female, or have a history of cytomegalovirus, hepatitis C, or diabetes (P<0.01, all). The lowest urgency patients had longer waitlist times and under the new allocation system received organs from shorter distances with decreased ischemic times (178 miles versus 269 miles, 3.1 versus 3.5 hours; P<0.001, all). There was no difference in posttransplantation survival (P<0.01, all). Conclusions Patients transplanted as lower urgency receive hearts from donors with additional comorbidities compared with higher urgency patients, but outcomes are similar at 1 year.

Cannabis use disorder among atrial fibrillation admissions, 2008-2018.

BACKGROUND: Despite changes inthe legality of cannabis use and the increasing prevalence of cannabis use disorder (CUD), there is little data investigating the association between CUD and inpatient atrial fibrillation (AF) hospitalizations. METHODS: Using the National Inpatient Sample, we identified Atrial Fibrillation (AF) hospitalizations with and without a codiagnosis of CUD using International Classification of Diseases diagnosis codes and compared demographics, socioeconomics, comorbidities, outcomes, and trends between cohorts. RESULTS: Between 2008 and 2018, we identified 5,155,789 admissions for AF of which 31,768 (0.6%) had a codiagnosis of CUD. The proportion of admissions with a history of CUD increased from 0.3% in 2008 to 1.0% in 2018 (p < .001). Hospital discharges of patients with CUD were significantly younger (53 vs. 72 years, p < .001), had a higher proportion of black race (CUD: 26.6% vs. 8.0%, p < .001), and had a higher proportion of income in the lowest income quartile than without a codiagnosis of CUD (CUD: 40.5% vs. 26.2%, p < .001). CONCLUSIONS: CUD is increasingly prevalent among AF hospitalizations, particularly among young patients. Codiagnosis of CUD in AF hospitalizations is also more common in underserved patients. As a result, it is important for future research to examine and understand the impact of CUD on this population, particularly in the light of changing legislation surrounding the legality of cannabis.

Forgone Medical Care Associated With Increased Health Care Costs Among the U.S. Heart Failure Population.

OBJECTIVES: The objective of this study was to describe the prevalence of patients with forgone/delayed care for heart failure (HF) and examine the associated demographic characteristics, health care utilization, and costs. BACKGROUND: HF is a leading cause of morbidity and mortality, with health care expenditures projected to increase 3-fold from 2012 to 2030. The proportion of HF patients with forgone/delayed medical care and the association with health care expenditures and utilization remain unknown. METHODS: Data on patients with HF were obtained from the Medical Expenditure Panel Survey to assess expenditures and health care utilization in the United States from 2004 to 2015. Patients with HF who reported forgone/delayed care, any missed or delayed medical treatment, were compared with those without care lapses. RESULTS: Overall, 16% of patients with HF reported forgone/delayed care, including 10% among the elderly (aged ≥65 years) and 27% among the nonelderly (aged <65 years). Patients with HF who reported forgone/delayed care had annual health care expenses $8,027 (95% CI: $1,181-$14,872) higher than those who did not. Among the elderly, those reporting forgone/delayed care had more emergency department visits (43% vs 58%; P < 0.05), and had higher annual inpatient costs (+$7,548; 95% CI: $1,109-$13,988) and total health care costs (+$10,581; 95% CI: $1,754-$19,409). Sixty percent of nonelderly and 46% of elderly patients with HF reported deferring care due to financial barriers. CONCLUSIONS: Nearly 1 in 6 patients with HF in the United States reported forgone/delayed medical care, with one-half attributing it to financial reasons, and this was associated with higher overall health care spending.

Personalizing the decision of dabigatran versus warfarin in atrial fibrillation: A secondary analysis of the Randomized Evaluation of Long-term anticoagulation therapY (RE-LY) trial.

BACKGROUND: The RE-LY (Randomized Evaluation of Long-Term Anticoagulation Therapy) trial demonstrated that higher-risk patients with atrial fibrillation had lower rates of stroke or systemic embolism and a similar rate of major bleeding, on average, when treated with dabigatran 150mg compared to warfarin. Since population-level averages may not apply to individual patients, estimating the heterogeneity of treatment effect can improve application of RE-LY in clinical practice. METHODS AND RESULTS: For 18040 patients randomized in RE-LY, we used patient-level data to develop multivariable models to predict the risk for stroke or systemic embolism and for major bleeding including all three treatment groups (dabigatran 110mg, dabigatran 150mg, and warfarin) over a median follow up of 2.0 years. The mean predicted absolute risk reduction (ARR) for stroke/systemic embolism with dabigatran 150mg compared to warfarin was 1.32% (range 11.6% lower to 3.30% higher risk). The mean predicted ARR for bleeding was 0.41% (range 8.93% lower to 63.4% higher risk). Patients with increased stroke/systemic embolism risk included those with prior stroke/TIA (OR 2.01), diabetics on warfarin (OR 2.00), and older patients on dabigatran 150mg (OR 1.68 for every 10-year increase). Major bleeding risk was higher in patients on aspirin (OR 1.25), with a history of diabetes (OR 1.34) or prior stroke/TIA (OR 1.22), those with heart failure on dabigatran 110mg (OR 1.52), older patients on either dabigatran 110mg or 150mg (OR 1.57 and 1.93, respectively, for each 10-year increase), and heavier patients on dabigatran 110mg or 150mg; patients in a region outside the United States and Canada and with better renal function had lower bleeding risk. CONCLUSIONS: There is substantial heterogeneity in the benefits and risks of dabigatran relative to warfarin among patients with atrial fibrillation. Using individualized estimates may enable shared decision making and facilitate more appropriate use of dabigatran; as such, it should be prospectively tested. CLINICAL TRIAL REGISTRATION: www.clinicaltrials.gov number, NCT00262600.

Comparison of Transcatheter and Open Mitral Valve Repair Among Patients With Mitral Regurgitation.

In 2013, the Food and Drug Administration approved the first transcatheter mitral valve repair (TMVr) device for degenerative mitral regurgitation for patients at prohibitive surgical risk. To better understand contemporary utilization trends and outcomes, we reviewed hospitalizations, identified using International Classification of Diseases, Ninth Revision and International Classification of Diseases, Tenth Revision codes, in which the patient underwent TMVr or mitral valve repair (MVr) with a diagnosis of mitral regurgitation, without stenosis, from the National (Nationwide) Inpatient Sample from 2014 to 2017. We included 10,020 hospitalizations in which the patient underwent TMVr and 5845 in which the patient underwent MVr and assessed trends in demographic characteristics, patient comorbidities, total hospital charges, and outcomes. Transcatheter mitral valve repair experienced exponential growth, increasing from 150 to 5115 over the study period (P<.001 for trend), whereas MVr grew to a lesser degree. The median length of stay for TMVr decreased from 4 to 2 days; mortality declined from 3.3% to 1.6% (P<.001 for both). Both TMVr and MVr rates of discharge home increased over the study period. Total charges for TMVr increased from $149,582 to $178,109, whereas those for MVr increased to a lesser degree, from $149,426 to $157,146 (P<.001 for both). Discharge disposition, length of stay, and in-hospital mortality all exhibited favorable trends for both procedures. Caution must be exercised in direct comparisons between procedures as they target somewhat different populations. With expanded indications for TMVr, we anticipate further increases in procedural volume, although the effect on MVr remains unclear.

National Trends in the Burden of Atrial Fibrillation During Hospital Admissions for Heart Failure.

Background Heart failure (HF) and atrial fibrillation (AF) frequently coexist and may be associated with worse HF outcomes, but there is limited contemporary evidence describing their combined prevalence. We examined current trends in AF among hospitalizations for HF with preserved (HFpEF) ejection fraction or HF with reduced ejection fraction (HFrEF) in the United States, including outcomes and costs. Methods and Results Using the National Inpatient Sample, we identified 10 392 189 hospitalizations for HF between 2008 and 2017, including 4 250 698 with comorbid AF (40.9%). HF hospitalizations with AF involved patients who were older (average age, 76.9 versus 68.8 years) and more likely White individuals (77.8% versus 59.1%; P<0.001 for both). HF with preserved ejection fraction hospitalizations had more comorbid AF than HF with reduced ejection fraction (44.9% versus 40.8%). Over time, the proportion of comorbid AF increased from 35.4% in 2008 to 45.4% in 2017, and patients were younger, more commonly men, and Black or Hispanic individuals. Comorbid hypertension, diabetes mellitus, and vascular disease all increased over time. HF hospitalizations with AF had higher in-hospital mortality than those without AF (3.6% versus 2.6%); mortality decreased over time for all HF (from 3.6% to 3.4%) but increased for HF with reduced ejection fraction (from 3.0% to 3.7%; P<0.001 for all). Median hospital charges were higher for HF admissions with AF and increased 40% over time (from $22 204 to $31 145; P<0.001). Conclusions AF is increasingly common among hospitalizations for HF and is associated with higher costs and in-hospital mortality. Over time, patients with HF and AF were younger, less likely to be White individuals, and had more comorbidities; in-hospital mortality decreased. Future research will need to address unique aspects of changing patient demographics and rising costs.

Intercountry Differences in Guideline-Directed Medical Therapy and Outcomes Among Patients With Heart Failure.

OBJECTIVES: The aim of this study was to examine patterns of care and clinical outcomes among patients with heart failure with reduced ejection fraction (HFrEF) in the United States and Canada. BACKGROUND: In the GUIDE-IT (Guiding Evidence Based Therapy Using Biomarker Intensified Treatment) trial, the use of N-terminal pro-B-type natriuretic peptide-guided titration of guideline-directed medical therapy (GDMT) was compared with usual care alone for patients with HFrEF in the United States and Canada. It remains unknown whether the country of enrollment had an impact on outcomes or GDMT use. METHODS: A total of 894 patients at 45 sites across the United States and Canada with HFrEF (ejection fraction ≤40%) were enrolled in the trial. Kaplan-Meier survival estimates stratified by country of enrollment were developed for the trial outcomes, and log-rank testing was compared between the groups. GDMT use and titration were also compared. RESULTS: U.S. patients were more likely to be younger, to be Black, to have higher body mass index, and to have histories of defibrillator placement or sleep apnea. Use of ß-blockers was significantly higher in Canada at baseline (99.3% vs. 94.0%; p = 0.01) and 6 months (99.0% vs. 94.1%; p = 0.04), and use of mineralocorticoid receptor antagonists was higher in Canada at 6 months (68.3% vs. 55.1%; p = 0.01). Canadian patients were less likely to experience the primary study endpoint (hazard ratio [HR]: 0.65; 95% confidence interval [CI]: 0.45 to 0.93; p = 0.01) due to decreased rates of HF hospitalization (HR: 0.57; 95% CI: 0.38 to 0.86; p = 0.003). The differences in outcomes were driven by increased heart failure hospitalization among U.S. Black patients. CONCLUSIONS: In GUIDE-IT, patients with HFrEF in Canada were significantly less likely to be hospitalized for heart failure. Differences in GDMT use, along with differences in sociodemographics and care delivery structures, may contribute to these differences, highlighting the importance of increasing diversity in clinical trials. (Guiding Evidence Based Therapy Using Biomarker Intensified Treatment [GUIDE-IT]; NCT01685840).

Changes in Use of Left Ventricular Assist Devices as Bridge to Transplantation With New Heart Allocation Policy.

OBJECTIVES: The goal of this study was to describe outcomes of patients with bridge to heart transplantation (BTT) after changes were made to the donor heart allocation system. BACKGROUND: Left ventricular assist devices (LVADs) have been used as a BTT. On October 18, 2018, the donor heart allocation system in the United States was updated. METHODS: This study identified adults in the United Network for Organ Sharing database with durable, continuous-flow LVAD at listing or implanted while listed between April 2017 and April 2020. Baseline recipient and donor characteristics, waitlist survival, and post-transplantation outcomes were compared pre- and post-allocation system change. RESULTS: A total of 1,794 patients met inclusion criteria: 983 in the pre-change period and 814 afterward. The number of patients listed with LVAD decreased nationally over time from 102 in April 2017 to 12 in April 2020 (p < 0.001). The proportion of patients with LVAD at time of transplant decreased from 47% to 14%. Before the change, the majority were Status 1A (75.8%) at transplantation; afterward, most were Status 2/3 (67.8%). Transplantation rates were not different (85.4% vs. 83.6%; p = 0.225), but waitlist time decreased in the post period (82 vs. 65 days; p = 0.004). Donors were more likely to be high risk (39.0% vs. 32.2%; p = 0.005), and both ischemic times and distance traveled increased (3.4 h vs. 3.1 h; p < 0.001; 199 miles vs. 82 miles; p < 0.001). Waitlist survival did not change, but post-transplantation survival was worse in patients with BTT post-change (p < 0.001). CONCLUSIONS: The number of patients with BTT on the transplant list decreased steadily and dramatically after the allocation system change. Although time to transplant decreased, there was an increase in post-transplant mortality. These data suggest that the risks and benefits of LVAD implantation as a BTT have changed under the new allocation system and that the appropriate indication for this treatment strategy warrants a re-evaluation.

Sex Differences in Patients Receiving Left Ventricular Assist Devices for End-Stage Heart Failure.

OBJECTIVES: This study sought to use INTERMACS (Interagency Registry for Mechanically Assisted Circulatory Support) results to evaluate sex differences in the use and clinical outcomes of left ventricular assist devices (LVAD). BACKGROUND: Despite a similar incidence of heart failure in men and women, prior studies have highlighted potential underuse of LVADs in women, and studies of clinical outcomes have yielded conflicting results. METHODS: Patients were enrolled from the INTERMACS study who underwent implantation of their first continuous-flow LVAD between 2008 and 2017, and survival analyses stratified by sex were conducted. RESULTS: Among the 18,868 patients, 3,984 (21.1%) were women. At 1 year, women were less likely to undergo heart transplantation than men (17.9% vs. 20.0%, respectively; p = 0.003). After multivariable adjustments, women had a higher risk of death (hazard ratio [HR]: 1.15; 95% confidence interval [CI]: 1.07 to 1.23; p < 0.001) and were more likely to incur post-implantation adverse events, including rehospitalization, bleeding, stroke, and pump thrombosis or device malfunction. Although women younger than 50 years of age had an increased risk of death compared to men of the same age (HR: 1.34; 95% CI: 1.12 to 1.6), men and women 65 years of age and older had a similar risk of death (HR: 1.09; 95% CI: 0.95 to 1.24). CONCLUSIONS: This study found that women had a higher risk of mortality and adverse events after LVAD. Only 1 in 5 LVADs were implanted in women, and women were less likely to receive a heart transplant than men. Further investigation is needed to understand the causes of adverse events and potential underuse of advanced treatment options in women.