INTRODUCTION:Cardiac inotrope medications administered to cardiac surgical patients carry steep risk-benefit trade-offs, yet wide inter-institutional variation exists in inotrope practices. Despite known wide variation in use of any inotrope for cardiac surgery, limited multicentre data exist regarding determinants of inotrope selection and time course for use. Additionally, the reasons that underpin how clinicians decide on inotrope usage and the factors that influence inotrope practice change are not well understood. METHODS AND ANALYSIS:This is an investigator-initiated, multicentre mixed methods study. Quantitative data will include electronic health records from an observational cohort of adult cardiac procedures within the Multicenter Perioperative Outcomes Group (MPOG) database, comprising cardiac surgical procedures from over 30 US academic and community hospitals. Additional quantitative data will be collected via surveys of clinicians involved in inotrope decision-making, contacted through an existing multicentre research and quality improvement infrastructure with engaged clinician representatives participating across MPOG hospitals. Qualitative data will be collected from open-ended questions within surveys, as well as semi-structured interviews with surveyed clinicians, sampled across approximately six institutions selected for diversity of settings and inotrope practices. An explanatory sequential mixed methods design will merge quantitative and qualitative data to develop meta-inferences explaining inotrope practices, as guided by an existing framework for characterising clinical practice variation and levers for practice change. ETHICS AND DISSEMINATION:The study is approved by the institutional review board at the University of Michigan Medical School (HUM00245353). Findings will be disseminated through peer-reviewed journals, conference proceedings and quality improvement forums. The study began in February 2025 and will continue until 2028.

Background: The accurate diagnosis of heart failure (HF) before major noncardiac surgery is frequently challenging. The impact of diagnostic accuracy for HF on intraoperative practice patterns and clinical outcomes remains unknown. Methods: We performed an observational study of adult patients undergoing major noncardiac surgery at an academic hospital from 2015 to 2019. A preoperative clinical diagnosis of HF was defined by keywords in the preoperative assessment or a diagnosis code. Medical records of patients with and without HF clinical diagnoses were reviewed by a multispecialty panel of physician experts to develop an adjudicated HF reference standard. The exposure of interest was an adjudicated diagnosis of heart failure. The primary outcome was volume of intraoperative fluid administered. The secondary outcome was postoperative acute kidney injury (AKI). Results: From 40 659 surgeries, a stratified subsample of 1018 patients were reviewed by a physician panel. Among patients with adjudicated diagnoses of HF, those without a clinical diagnosis (false negatives) more commonly had preserved left ventricular ejection fractions and fewer comorbidities. Compared with false negatives, an accurate diagnosis of HF (true positives) was associated with 470 ml (95% confidence interval: 120-830; P1/40.009) lower intraoperative fluid administration and lower risk of AKI (adjusted odds ratio:0.39, 95% confidence interval 0.18-0.89). For patients without adjudicated diagnoses of HF, non-HF was not associated with differences in either fluids administered or AKI. Conclusions: An accurate preoperative diagnosis of heart failure before noncardiac surgery is associated with reduced intraoperative fluid administration and less acute kidney injury. Targeted efforts to improve preoperative diagnostic accuracy for heart failure may improve perioperative outcomes.

Background The association of significant postimplant mitral regurgitation (PI-MR) with left ventricular assist device (LVAD) outcomes remains controversial. We investigated PI-MR in the setting of contemporary LVAD therapy. Methods The Society of Thoracic Surgeons Intermacs National Database was queried and identified 2858 patients with a fully magnetically levitated centrifugal flow LVAD implanted from 2017 to 2021 who met study inclusion and exclusion criteria. Kaplan-Meir methodology and Cox proportional hazard modeling were used to evaluate the long-term influence of PI-MR on post-LVAD outcomes conditional on surviving 3 months post-LVAD implant. Significant PI-MR was defined as moderate-to-severe MR at the 1- or 3-month follow-up echocardiogram. Results There were 340 patients with significant PI-MR and 2518 without PI-MR following LVAD implant. Those with significant PI-MR were younger (age 53.2 vs 57.7 years; P < .001), more likely to have a nonischemic cardiomyopathy etiology of heart failure (66.5% vs 51.5%; P < .0001), preoperative moderate-to-severe tricuspid regurgitation (51.5% vs 37.6%; P < .001), and concomitant tricuspid valve replacement/repair (17.1% vs 9.4%; < .001). Of those with preoperative significant MR, 17% (n = 274) had significant PI-MR. Significant PI-MR was associated with worse 2-year survival (88.3% vs 79.5%; P = .008), risk for readmission (hazard ratio, 1.19; P = .032) and subsequent renal failure (hazard ratio, 1.84; P = .014). Conclusions Significant PI-MR following contemporary LVAD implant adversely influences long-term survival and readmission. Strategies to prevent or intervene upon significant PI-MR require further investigation.

BACKGROUND:Infections following durable left ventricular assist device (dLVAD) implantation are common and associated with increased morbidity and mortality. Despite documented interhospital variability, few studies have identified strategies to mitigate their occurrence. This national study uses a multistage mixed methods design to develop a customizable and deployable toolkit of expert-guided recommendations to reduce infections post-dLVAD. METHODS:Using purposeful sampling, participants (eg, clinical and operational ventricular assist device [VAD] team members) from low, medium, and high-performance hospitals (based on their risk-adjusted, 90-day post-implantation infection rates) across the United States were interviewed to assess factors contributing to postdLVAD infections. Draft toolkit recommendations were iteratively developed after integrating thematically analyzed qualitative and quantitative data from a merged national registry with Medicare and hospital survey data. A national advisory team of VAD subject matter experts provided mixed methods input to refine the toolkit's content and structure. RESULTS:Seventy-three clinical and operational VAD team members across 8 US hospitals were interviewed, spanning low (n=4), medium (n=1) and high (n=3) performance groups. Fourteen subject matter experts provided stakeholder feedback to refine the toolkit. The resulting toolkit contains 39 infection prevention recommendations that address VAD program care processes (eg, real-time provider communication), clinicians (eg, multidisciplinary protocol development), patients and caregivers (eg, engaging patient advisors in patient education), and VAD leadership (eg, unit and service level data reporting). Accompanying resources (eg, team-based exercises, data collection worksheets) support implementing and evaluating site-specific strategies. CONCLUSIONS:Using mixed methods approaches, an infection prevention toolkit was developed to enhance care coordination among VAD team members and mitigate postdLVAD infections. Future work should evaluate the effectiveness of implementing this infection prevention toolkit within the dLVAD setting.

BACKGROUND:Pretransplant psychosocial risk (PSR) assessment is subjective, so we investigated potential biases and the relationship between assessed PSR and post-transplant outcomes at our heart transplant center. METHODS:Between 05/2004 and 01/2021, 479 heart transplant (HT) recipients had a pre-transplant psychosocial evaluation, at which a social worker collected information about 25 characteristics and categorized the candidate's PSR for post-transplant death. Relationships between PSR and post-transplant outcomes (death, hospitalization and rejection) were evaluated. Possible biases in PSR evaluation were examined by assessing the independent relationships among race, sex, psychosocial characteristics, additional socioeconomic characteristics imputed from U.S. census data, and the PSR categorization. RESULTS:Psychosocial risk was categorized as low (399), medium (57) or high (23). Medium- or high-risk patients were younger and more likely to have psychosocial risk factors and live in less affluent neighborhoods. Race and sex were not found to influence the PSR categorization (both P = 0.4). Neighborhood affluence score (OR 0.30; P = 0.009) and family/social support (OR 500; P < 0.001) were strongly and independently associated with PSR categorization; less affluent patients and those without family/social support were more likely to be classified as being at medium or high risk. Medium- or high-risk categorization was not associated with increased mortality or hospitalization rates after HT (P = 0.5 and 0.3, respectively), but it was associated with increased risk for experiencing rejection (HR 1.7, CI 1.02-2.90). CONCLUSION:Medium or high PSR was associated with a greater risk of rejection but not of hospitalization or death. There was no indication of race or sex bias in our program's preoperative psychosocial evaluations, but patients' affluence may have influenced decision making.

BACKGROUND:For patients on durable left ventricular assist devices, prior work has documented that more shared patients among clinicians (connectedness) is associated with improved long-term outcomes. This study examines the association between preadmission clinician connectedness, patient acuity, and postimplant outcomes including infections. METHODS:The Society of Thoracic Surgeons Intermacs National Database was linked to Medicare claims to identify patients undergoing durable left ventricular assist device implantation between 2009 and 2017. Patients were stratified by terciles (low, moderate, high) of provider connectedness. The association between provider connectedness and major infections within 180 days of implant was evaluated by regression analysis, with an interaction term to assess effect modification by patient acuity via Intermacs Patient Profile. RESULTS:Of the 4985 patients across 127 hospitals, those within networks of low vs high provider connectedness were more commonly Intermacs Profile 1 (12.6% vs 6.7%, P < .001), and designated for destination therapy (3.4% vs 0.7%, P = .002). Patients cared for in centers with high connectedness had a lower risk of infection (β = -0.100, P < .026) and fewer total infections (β = -0.215, P = .014). The risk of infection was most pronounced in higher acuity Intermacs Profile 1 patients (P = .006). CONCLUSIONS:Patients in networks with lower clinician connectedness (fewer shared patients) presented with higher acuity. After adjusting for preimplantation risk, lower clinician connectedness was associated with an increased risk of major infections, particularly among high-acuity patients. Measuring and improving network connectedness may be an important quality metric for timely access to advanced heart failure treatment and reducing complications.

Disease risk prediction models play an important role in preventing disease developments in modern healthcare. However, the lack of focus on high-risk patients has hindered the large-scale practical application of these models, especially considering the limitation of medical resources available for following up on patients who are deemed high-risk. In this study, we propose a novel and practical approach that focuses on minimizing the number of false positive observations among high-risk patients by introducing the Highest-k Loss. The solution is to estimate the weights of the highest k scores with a differentiable estimation of the sorting operation and apply the weights to the loss function. We extracted 253,680 survey responses from a public dataset of the U.S. health survey system to define a diabetes prediction task. This study employs nested cross-validation as well as an aggregated model applied to an independent test set to systematically evaluate the proposed method. Compared with traditional binary cross entropy loss and Focal loss, the Highest-k loss improved the precision (positive predictive value) for the highest 1% scores by 0.05 (95% CI: 0.041-0.055), the highest 5% scores by 0.03 (95% CI: 0.024-0.032), and the highest 10% scores by 0.02 (95% CI: 0.016-0.021). The introduced Highest-k loss function addresses the problem of prevailing risk prediction models and offers a practical solution that focuses on patients with the k highest predictive scores who can realistically receive an intervention as opposed to the entire patient population.

Purpose: Impact of significant post-implant mitral regurgitation (PI-MR) on left ventricular assist device (LVAD) outcomes remains controversial. We investigated the effect of PI-MR from a real-world experience.

BACKGROUND Left ventricular assist device (LVAD) use remains uncommon in advanced heart failure (HF) patients not dependent on inotropes. OBJECTIVES Before considering a randomized trial comparing a strategy of earlier use of LVAD to continued medical therapy, a better understanding is needed of the clinical trajectory of ambulatory patients with advanced systolic HF on optimal guideline-directed medical therapy (GDMT). METHODS REVIVAL enrolled 400 patients with advanced ambulatory systolic HF, >= 1 HF mortality risk marker (>= 2 HF hospitalizations past year; or HF hospitalization and high natriuretic peptide; or no HF hospitalizations but low peak oxygen consumption, 6-minute walk, serum sodium, HF survival score or Seattle HF model predicted survival), and no LVAD contraindication at 21 LVAD centers from July 2015 to June 2016. Patients were followed for 2 years or until a primary outcome (death, durable ventricular assist device, or urgent transplant). Clinical outcomes and health-related quality of life were evaluated. RESULTS Mean baseline left ventricular ejection fraction was 21%, median 6-minute walk was 341 m, and 92% were Interagency Registry for Mechanically Assisted Circulatory Support profiles 5 to 7. Adherence to GDMT and electrical device therapies was robust. Composite primary outcome occurred in 22% and 37% at 1 and 2 years, with death alone in 8% and 16%, respectively. Patients surviving for 2 years maintained GDMT intensity and had no decline in health-related quality of life. CONCLUSIONS Structured, serial follow-up at programs with expertise in caring for advanced ambulatory systolic HF patients facilitates triage for advanced therapies. Better strategies are still needed to avoid deaths in a small but significant group of patients who die without advanced therapies. REVIVAL patients not selected for VAD or transplant have robust survival and patient-reported outcomes, which challenges advocacy for earlier VAD implantation. (Registry Evaluation of Vital Information for VADs in Ambulatory Life [REVIVAL]; NCT01369407) (JACC Heart Fail. 2024;12:1734-1746) (c) 2024 the American College of Cardiology Foundation. Published by Elsevier. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Purpose: Intermacs Patient Profiles (IPP) are subjective assessments of patient acuity of illness assigned at the time of durable left ventricular assist device implantation (dLVAD). Previous studies have demonstrated provider variability with IPP assignment. We developed a novel algorithm to derive a patient's IPP acuity of illness to assist clinicians with IPP assignment.

Background: Despite well-known morbidity and mortality benefits, implementation of guideline-directed medical therapy (GDMT) for HFrEF patients remains suboptimal. Understanding the center-level variation in observed-to-expected GDMT prescribing could support targeted improvement initiatives. Hypothesis: The risk-adjusted observed to expected (O/E) ratio for GDMT prescribing would vary between hospitals and be associated with mortality and readmissions. Methods: This cohort study included 100% of Medicare fee-for-service beneficiaries admitted for HFrEF and discharged between Jan 2009 and Dec 2017. Patients were excluded if they were readmitted or died within 60 days of discharge. The primary outcomes were: (1) prescription filling of ≥2 of 3 classes of GDMT (proposed quality measure of GDMT; SGLT2i not yet approved for HFrEF) within 60 days and (2) composite endpoint of death and readmission within 61-120 days post-discharge. The exposures of interest were: (1) center O/E GDMT prescription ratios to evaluate interhospital hospital variability and (2) GDMT quality measure prescription. Risk adjustment was performed via logistic regression, conditioning on demographics, comorbidities, neighborhood distress score, and pre-admission medication utilization. Results: In total, 296,900 patients were treated at 1,917 hospitals. Patients had a mean (SD) age of 77 (12) years and were 47.0% female (n=139,398). BB, ACE/ARB, and MRA were filled by 56.5%, 48.5%, and 21.2% of patients, respectively. In total, 42% were prescribed and filled ≥2 GDMT classes. Interhospital variability existed in O/E GDMT prescription (Figure). The adjusted difference in GDMT quality metric prescribing was 23.2% between top and bottom quartile hospitals (52.6% and 29.5%). GDMT prescription was associated with a 5.98% (95% CI -5.5 - -6.46%) lower probability of risk-adjusted death or readmission per patient in the subsequent two months. Conclusions: Large-scale interhospital variability exists in GDMT prescribing for HFrEF patients. While optimal GDMT is indicated for all HFrEF patients, assessing center-level O/E GDMT prescribing enables comparisons against achievable performance benchmarks and should be considered a potential quality indicator.

AIMS:Benefits of mineralocorticoid receptor antagonists (MRAs) in heart failure with preserved and mildly reduced ejection fraction (HFpEF/HFmrEF) have not been established. Conventional randomized controlled trials are complex and expensive. The Spironolactone Initiation Registry Randomized Interventional Trial in Heart Failure with Preserved Ejection Fraction (SPIRRIT-HFpEF) is a unique pragmatic registry-based randomized controlled trial. METHODS:SPIRRIT-HFpEF is a multicentre, prospective, randomized, open-label, blinded endpoint trial conducted on platforms in the Swedish Heart Failure Registry (SwedeHF) and the United States (US) Trial Innovation Network. Patients with HFpEF/HFmrEF are randomized 1:1 to spironolactone (or eplerenone) in addition to usual care, versus usual care alone. The primary outcome is total number of cardiovascular deaths and hospitalizations for heart failure. Outcomes are collected from Swedish administrative complete coverage registries and a US call centre and subsequently adjudicated. Simple eligibility criteria were based on data available in SwedeHF: heart failure as outpatient or at discharge from hospital, left ventricular ejection fraction ≥40%, N-terminal pro-B-type natriuretic peptide >300 ng/L (in sinus rhythm) or >750 ng/L (in atrial fibrillation), with pre-specified adjustment for elevated body mass index, and chronic loop diuretic use. Power and sample size assessments were based on an event-driven design allowing enrolment over approximately 6 years, and application of hazard ratios from the TOPCAT trial, Americas subset. The final sample size is expected to be approximately 2400 patients. CONCLUSION:SPIRRIT-HFpEF will be informative on the effectiveness of generic MRAs in HFpEF and HFmrEF, and on the feasibility of conducting pragmatic and registry-based trials in heart failure and other chronic conditions.

Purpose: Cardiac rehabilitation (CR) is an evidence-based, guideline-endorsed therapy for patients with heart failure with reduced ejection fraction (HFrEF) but is broadly underutilized. Identifying structural factors contributing to increased CR use may inform quality improvement efforts. The objective here was to associate hospitalization at a center providing advanced heart failure (HF) therapies and subsequent CR participation among patients with HFrEF. Methods: A retrospective analysis was performed on a 20% sample of Medicare beneficiaries primarily hospitalized with an HFrEF diagnosis between January 2008 and December 2018. Outpatient claims were used to identify CR use (no/yes), days to first session, number of attended sessions, and completion of 36 sessions. The association between advanced HF status (hospitals performing heart transplantation or ventricular assist device implantations) and CR participation was evaluated with logistic regression, accounting for patient, hospital, and regional factors. Results: Among 143 392 Medicare beneficiaries, 29 487 (20.6%) were admitted to advanced HF centers (HFCs) and 5317 (3.7%) attended a single CR session within 1 yr of discharge. In multivariable analysis, advanced HFC status was associated with significantly greater relative odds of participating in CR (OR = 2.20: 95% CI, 2.08-2.33; P < .001) and earlier initiation of CR participation (-8.5 d; 95% CI, -12.6 to 4.4; P < .001). Advanced HFC status had little to no association with the intensity of CR participation (number of visits or 36 visit completion). Conclusions: Medicare beneficiaries hospitalized for HF were more likely to attend CR after discharge if admitted to an advanced HFC than a nonadvanced HFC.

BACKGROUND: Gastrointestinal bleeding (GIB) results in frequent hospitalizations and impairs quality of life in durable left ventricular assist device (LVAD) recipients. Anticipation of these events before implantation could have important implications for patient selection and management. METHODS: The study population included all adult HeartMate 3 (HM3) primary LVAD recipients enrolled in the STS Intermacs registry from January 2017 to December 2020. Using multivariable modeling methodologies, we investigated the relationships between preimplantation characteristics and postimplant bleeding, bleeding and death, and additional bleeding episodes on subsequent bleeding episodes and created a risk score to predict the likelihood of post-LVAD GIB based solely on preimplantation factors. RESULTS: Of 6,425 patients who received an HM3 LVAD, 1,010 (15.7%) patients experienced GIB. Thirteen preimplantation factors were independent predictors of post-LVAD GIB. A risk score was created from these factors and calculated for each patient. By 3 years postimplant, GIB occurred in 11%, 26%, and 43% of low-, medium- and high -risk patients, respectively. Experiencing 1 post-LVAD GIB event was associated with an increased risk for further GIB events, with 33.9% of patients experiencing at least 1 recurrence. While post-LVAD GIB was associated with mortality, there was no relationship between number of GIB events and death. CONCLUSIONS: The Michigan Bleeding Risk Model is a simple tool, which facilitates the prediction of post-LVAD GIB in HM3 recipients using 13 preimplant variables. The implementation of this tool may help in the risk stratification process and may have therapeutic and clinical implications in HM3 LVAD recipients. J Heart Lung Transplant 2024;43:604-614 (c) 2023 International Society for Heart and Lung Transplantation. All rights reserved.

While mixed methods research is increasingly used to examine determinants of unwarranted variability in healthcare delivery and outcomes, novel integrative approaches are required to meet the needs of mixed methods healthcare delivery research. This article describes novel refining strategies that enhance the linkage between qualitative and quantitative dimensions of a mixed methods healthcare delivery research study. Leveraging our study experiences, this paper demonstrates several refining strategies: (1) using mediated allocation concealment to facilitate qualitative sampling; (2) informing qualitative inquiry through quantitative analytics; and (3) training and immersing multidisciplinary researchers in qualitative data collection and analysis. Developing and implementing strategies in mixed methods healthcare delivery research could advance methodological rigor and strengthen multidisciplinary collaboration.

BACKGROUND:Heart transplantation (HT) survival and waitlist times are established outcome metrics. Patient-centered HT outcomes are insufficiently characterized. This study evaluates the role of days alive and outside the hospital (DAOH) as a candidate patient-centered HT performance measure. METHODS:The study cohort included Medicare beneficiaries undergoing HT (July 2008-December 2017). The percent of days outside of hospital (%DOH) 6 months before (%DOH-BF) and percent of days alive outside of hospital 12 months after HT (%DAOH-AF) were evaluated along with adverse events (AEs, early: ≤3 months; late: 4-12 months). Patients were stratified by patient %DAOH-AF terciles. Risk-adjusted %DAOH was evaluated across hospitals. RESULTS:A total of 5,104 beneficiaries underwent HT across 108 hospitals. Median [interquartile range (IQR)] age was 62 [53-67] years, 23.9% were female, and 21.4% were African-American. The overall median %DOAH-AF was 92.9% [83.8%, 95.9%], varying by tercile: low 71.8% [4.9%, 83.6%], intermediate 92.9% [91%, 94%]; high 96.4% [95.9%, 97.3%]. The lowest (vs highest) tercile %DAOH-AF had a lower median %DOH-BF (88% [73%-97%] vs 92% [81%-98%]) and longer post-HT inpatient stay (54 [36-81] vs 13 [10-15] days). After HT, the lowest versus highest tercile had greater AEs burden in the early (allograft failure [16.1% vs 1.6%], stroke [12.1% vs 2.3%]) and late (stroke [5.1% vs 1.9%], sternal wound infection [5.0% vs 0.8%]) phases post-HT. The mean hospital %DAOHadj was 80.5% (min:max 57.7%-96.7%). CONCLUSIONS:Post-HT %DAOH varies across beneficiaries and hospitals and is associated with AEs. Further research is warranted to assess the role and validity of %DAOH as an HT quality metric.

Heart failure (HF) is a progressive disease. It is estimated that more than 250,000 patients suffer from advanced HF with reduced ejection fraction refractory to medical therapy. With limited donor pool for heart transplant, continue flow left ventricle assist device (LVAD) is a lifesaving treatment option for patients with advanced HF. This review will provide an update on indications, contraindications, and associated adverse events for LVAD support with a summary of the current outcomes data.

Background Adult patients surviving with congenital heart disease (ACHD) is growing. We examine the factors associated with heart transplant outcomes in this challenging population with complex anatomy requiring redo-surgeries. Methods We reviewed the United Network for Organ Sharing-Standard Transplant Analysis and Research database and analyzed 35,952 heart transplants from January 1st, 2000, to September 30th, 2018. We compared transplant characteristics for ischemic cardiomyopathy (ICM) (n = 14,236), nonischemic cardiomyopathy (NICM) (n = 20,676), and ACHD (n = 1040). Mean follow-up was 6.20 ± 4.84 years. Kaplan–Meier survival curves and Cox-proportional hazards analysis were used to analyze survival data. Results Multivariable analysis confirmed that ACHD was associated greater in-hospital death compared to ICM (HR = 0.54, P < 0.001) and NICM (HR = 0.46, P < 0.001). Notable factors associated with increased mortality were history of cerebrovascular disease (HR = 1.11, P = 0.026), prior history of malignancy (HR = 1.12, P = 0.006), pre-transplant biventricular support (HR = 1.12, P = 0.069), postoperative stroke (HR = 1.47, P < 0.001) and postoperative dialysis (HR = 1.71, P < 0.001). ACHD transplants had a longer donor heart ischemic time ( P < 0.001) and trend towards more deaths from primary graft dysfunction ( P = 0.07). In-hospital deaths were more likely with ACHD and use of mechanical support such as use of right ventricular assist device (HR = 2.20, P = 0.049), biventricular support (HR = 1.62, P < 0.001) and extracorporeal membrane oxygenation (HR = 2.36, P < 0.001). Conditional survival after censoring hospital deaths was significantly higher in ACHD ( P < 0.001). Conclusion Heart transplant in ACHD is associated with a higher post-operative mortality given anatomical complexity but a better long-term conditional survival. Normothermic donor heart perfusion may improve outcomes in the ACHD population by reducing the impact of longer ischemic times.