Chirinos, Julio A.

Abstract Background Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous syndrome comprising multiple pathophysiological phenotypes. HFpEF trials have largely enrolled diverse populations and reported average treatment effects, consistently yielding neutral results that may obscure drug-specific benefits within distinct subgroups. To address this issue, we employ an interaction-based that incorporates treatment-by-variable interactions to uncover drug-specific responses. Methods We leveraged four HFpEF clinical trials (TOPCAT, RELAX, NEAT-HFpEF, INDIE-HFpEF) and developed a framework comprising two complementary approaches. The first employed a prognostic responder model to evaluate whether conventional responder definitions reflect treatment-specific benefit or instead capture favorable clinical trajectories common to both treatment and placebo groups. The second used an interaction-based individual treatment effect (ITE) modeling to identify baseline variables that modify therapy effect, distinguishing drug-specific response from prognostic phenotypes. Results Although the prognostic responder model demonstrated good discrimination, further analisys suggested it primarily captured a prognostic signal associated with favorable clinical trajectories common to both treatment and placebo arms. In contrast, the ITE model identified distinct, drug-specific effect modifiers across trials (cardiorenal-inflammatory for spironolactone (TOPCAT), NO-mediated anti-inflammatory for isosorbide mononitrate (NEAT-HFpEF), afterload-reducing for inorganic nitrite (INDIE-HFpEF), and anti–volume-overload for sildenafil (RELAX). Each ITE model demonstrated significance only within its own trial suggesting drug-specific signal. Conclusions The proposed method identifies mechanism-specific effect modifiers, and uncovers clinically meaningful heterogeneity in treatment response, which is not captured by conventional MCID-based approaches. Although exploratory, these findings support phenotype-guided therapy in HFpEF and argue for phenotype-informed trial design to enhance treatment-effect detection and therapy targeting. Graphical Abstract

Introduction: Patients with heart failure with preserved ejection fraction (HFpEF) have a high burden of comorbidities. To recognize the complex interplay of obesity, diabetes, and chronic kidney disease (CKD) in patients with cardiovascular disease, the cardiovascular-kidney-metabolic (CKM) syndrome was recently defined, but data on the burden of CKM in HFpEF is limited. Aim: We sought to describe the prevalence of CKM components in HFpEF leveraging data from control participants in clinical trials and NHANES. Methods: We analyzed data presented in publications from four randomized clinical trials that enrolled participants with HFpEF (all of which are available via NHLBI BioLINCC and will be included in the extant HeartShare dataset): TOPCAT, RELAX, NEAT-HFpEF, and INDIE. We abstracted baseline demographic and clinical variables from study publications to define CKM components (e.g., body mass index [BMI], diabetes status, hypertension, CKD status). We compared prevalence of CKM in these trials with a representative sample of US adults with self-reported history of heart failure (HF) from NHANES 2011-2018. Results: We included 1937 patients with HFpEF from four trials with enrollment between 2006-2016 and 715 adults representing 5.6 million adults aged ≥40 years with a self-report of HF between 2011-2018 from NHANES ( Table ). Mean age was similar among enrolled trial participants with HFpEF and those with HF in NHANES (~68-69 years). Mean BMI was in the obesity range and was similar among trial participants with HFpEF and HF in NHANES (31-35 kg/m 2 ). A significant proportion of individuals had hypertension in HFpEF trials (>80%) and in the NHANES sample with HF (89%). The proportion of stage ≥ 3 CKD in HFpEF trials (≥ 37%) was similar to the NHANES sample with HF (37%). Results are shown in Table . Conclusions: Patients with HFpEF enrolled in clinical trials and those with HF in general population are significantly enriched with CKM components that may contribute to morbidity and mortality. Similar prevalence estimates were observed despite variability in trial inclusion criteria and heterogeneity in defining HFpEF and highlight CKM as a central target for HFpEF management.

Abstract Background Systemic arterial compliance and venous capacitance are typically impaired in patients with heart failure with preserved ejection fraction (HFpEF), contributing to hemodynamic congestion with stress. Sodium-glucose cotransporter-2 inhibitors (SGLT2i) reduce hemodynamic congestion and improve clinical outcomes in patients with HFpEF, but the mechanisms remain unclear. Purpose This study tested the hypothesis that SGLT2i dapagliflozin would improve systemic arterial compliance and venous capacitance during exercise in patients with HFpEF. Methods In this secondary analysis from the RCT trial, patients with HFpEF underwent invasive hemodynamic exercise testing at baseline and following treatment for 24 weeks with dapagliflozin or placebo. Patients were required to display pulmonary capillary wedge pressure (PCWP) ≥25 mmHg during exercise at the time of baseline evaluation. Radial artery pressure (BP) was measured continuously using a fluid-filled catheter with transformation to aortic pressure, central hemodynamics were measured using high-fidelity micromanometers, and stressed blood volume was estimated (eSBV) from hemodynamic indices fit to a comprehensive cardiovascular model. Results A total of 37 patients completed the study and were included in this analysis (21 dapagliflozin and 16 placebo). Patients were predominantly women (24/37, 65%) and older (mean age 67 years). There was no statistically significant effect of dapagliflozin on resting BP, but dapagliflozin reduced systolic BP during peak exercise (estimated treatment difference [ETD], -18.8 mmHg, 95% CI: -33.9 to -3.7, P=0.016) (Figure 1A). Dapagliflozin improved exertional total arterial compliance (TAC) index (ETD, 0.06 mL/mmHg/m2, 95% CI: 0.003 to 0.11, P=0.039) (Figure 1B) and aortic root characteristic impedance (ETD, -2.6 mmHg/ml*sec, 95% CI: -5.1 to -0.03, P=0.048) during peak exercise, with no significant effect on systemic vascular resistance. Dapagliflozin reduced eSBV at rest and during peak exercise (ETD, -292 mmHg, 95% CI: -530 to -53, P=0.018) (Figure 1C), and improved venous capacitance evidenced by a decline in ratio of eSBV to total blood volume (ETD, -7.3%, 95% CI -13.3 to -1.3, P=0.020). Each of these effects of dapagliflozin during peak exercise were also observed during matched 20W exercise intensity. Improvements in TAC index and eSBV were correlated with decreases in body weight, and reduction in systolic BP with treatment was correlated with the change in eSBV during exercise (r=0.40, P=0.019) (Figure 2A). Decreases in BP were correlated with reduction in PCWP during exercise (r=0.56, P<0.001) (Figure 2B). Conclusion In patients with HFpEF, treatment with dapagliflozin improved systemic arterial compliance and venous capacitance during exercise, while reducing aortic characteristic impedance, suggesting a reduction in arterial wall stiffness. These vascular effects may partially explain the clinical benefits with SGLT2i in HFpEF.

BACKGROUND: Systemic arterial compliance and venous capacitance are typically impaired in patients with heart failure with preserved ejection fraction (HFpEF), contributing to hemodynamic congestion with stress. Sodium-glucose cotransporter-2 inhibitors reduce hemodynamic congestion and improve clinical outcomes in patients with HFpEF, but the mechanisms remain unclear. This study tested the hypothesis that Dapagliflozin would improve systemic arterial compliance and venous capacitance during exercise in patients with HFpEF. METHODS: In this secondary analysis from the CAMEO-DAPA trial (Cardiac and Metabolic Effects of Dapagliflozin in Heart Failure With Preserved Ejection Fraction Trial), 37 patients with HFpEF (mean age 68 ± 9 years, women 65%) underwent invasive hemodynamic exercise testing with simultaneous echocardiography at baseline and following treatment for 24 weeks with Dapagliflozin or placebo. Radial artery pressure (BP) was measured continuously using a fluid-filled catheter with transformation to aortic pressure, central hemodynamics were measured using high-fidelity micromanometers, and stressed blood volume was estimated from hemodynamic indices fit to a comprehensive cardiovascular model. RESULTS: There was no statistically significant effect of Dapagliflozin on resting BP, but Dapagliflozin reduced systolic BP during peak exercise (estimated treatment difference [ETD], −18.8 mm Hg [95% CI, −33.9 to −3.7] P =0.016). Reduction in BP was related to improved exertional total arterial compliance (ETD, 0.06 mL/mm Hg/m 2 [95% CI, 0.003–0.11] P =0.039) and aortic root characteristic impedance (ETD, −2.6 mm Hg/mL*sec [95% CI: −5.1 to −0.03] P =0.048), with no significant effect on systemic vascular resistance. Dapagliflozin reduced estimated stressed blood volume at rest and during peak exercise (ETD, −292 mm Hg [95% CI, −530 to −53] P =0.018), and improved venous capacitance evidenced by a decline in ratio of estimated stressed blood volume to total blood volume (ETD, −7.3% [95% CI, −13.3 to −1.3] P =0.020). Each of these effects of Dapagliflozin at peak exercise were also observed during matched 20W exercise intensity. Improvements in total arterial compliance and estimated stressed blood volume were correlated with decreases in body weight, and reduction in systolic BP with treatment was correlated with the change in estimated stressed blood volume during exercise (r=0.40, P =0.019). Decreases in BP were correlated with reduction in pulmonary capillary wedge pressure during exercise (r=0.56, P <0.001). CONCLUSIONS: In patients with HFpEF, treatment with Dapagliflozin improved systemic arterial compliance and venous capacitance during exercise, while reducing aortic characteristic impedance, suggesting a reduction in arterial wall stiffness. These vascular effects may partially explain the clinical benefits with sodium-glucose cotransporter-2 inhibitors in HFpEF. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT04730947.

Abstract BACKGROUND The purpose of this document is to provide clinicians with guidance, using expert consensus, to help summarize evidence and offer practical recommendations. METHODS Expert Consensus Documents are intended to provide guidance for clinicians in areas in which there are no clinical practice guidelines, especially for new and evolving tests such as arterial stiffness measurements, until any formal guidelines are released. RESULTS This expert consensus document is intended as a source of information for decision-making and to guide clinician–patient discussions in various clinical scenarios. CONCLUSIONS The goal is to help clinicians and patients make a more informed decision together.

Heart failure with preserved ejection fraction (HFpEF), a major public health problem that is rising in prevalence, is associated with high morbidity and mortality and is considered to be the greatest unmet need in cardiovascular medicine today because of a general lack of effective treatments. To address this challenging syndrome, the National Heart, Lung, and Blood Institute convened a working group made up of experts in HFpEF and novel research methodologies to discuss research gaps and to prioritize research directions over the next decade. Here, we summarize the discussion of the working group, followed by key recommendations for future research priorities. There was uniform recognition that HFpEF is a highly integrated, multiorgan, systemic disorder requiring a multipronged investigative approach in both humans and animal models to improve understanding of mechanisms and treatment of HFpEF. It was recognized that advances in the understanding of basic mechanisms and the roles of inflammation, macrovascular and microvascular dysfunction, fibrosis, and tissue remodeling are needed and ideally would be obtained from (1) improved animal models, including large animal models, which incorporate the effects of aging and associated comorbid conditions; (2) repositories of deeply phenotyped physiological data and human tissue, made accessible to researchers to enhance collaboration and research advances; and (3) novel research methods that take advantage of computational advances and multiscale modeling for the analysis of complex, high-density data across multiple domains. The working group emphasized the need for interactions among basic, translational, clinical, and epidemiological scientists and across organ systems and cell types, leveraging different areas or research focus, and between research centers. A network of collaborative centers to accelerate basic, translational, and clinical research of pathobiological mechanisms and treatment strategies in HFpEF was discussed as an example of a strategy to advance research progress. This resource would facilitate comprehensive, deep phenotyping of a multicenter HFpEF patient cohort with standardized protocols and a robust biorepository. The research priorities outlined in this document are meant to stimulate scientific advances in HFpEF by providing a road map for future collaborative investigations among a diverse group of scientists across multiple domains.

Background Cardiac resynchronization therapy results in improved ejection fraction in patients with heart failure. We sought to determine whether these effects were mediated by changes in contractility, afterload, or volumes. Methods and Results In 610 patients with New York Heart Association class I/ II heart failure from the Re synchronization Reverses Remodeling in Systolic Left Ventricular Dysfunction ( REVERSE ) study, we performed detailed quantitative echocardiography assessment prior to and following cardiac resynchronization therapy. We derived measures of contractility (the slope [end‐systolic elastance] and the volume intercept of the end‐systolic pressure–volume relationship, stroke work, and preload recruitable stroke work), measures of arterial load and ventricular–arterial coupling, and measures of chamber size (volume intercept, end‐systolic and end‐diastolic volumes). At 6 and 12 months, cardiac resynchronization therapy was associated with a reduction in the volume intercept and end‐systolic and end‐diastolic volumes ( P <0.01). There were no consistent effects on end‐systolic elastance, stroke work, preload recruitable stroke work, or ventricular–arterial coupling. In the active cardiac resynchronization therapy population, baseline measures of arterial load were associated with the clinical composite score (odds ratio 1.30, 95% CI 1.04 to 1.63, P =0.02). The volume intercept was associated with mortality (hazard ratio 1.90, 95% CI 1.01 to 3.59, P =0.047) and more modestly with the combined end point of mortality or heart failure hospitalization (hazard ratio 1.48, 95% CI 0.8 to 2.25, P =0.06). In contrast, end‐systolic elastance, stroke work, preload recruitable stroke work, and ventricular–arterial coupling were not associated with any outcomes. Conclusion In patients with NYHA Class I/ II heart failure, cardiac resynchronization therapy exerts favorable changes in left ventricular end‐systolic and end‐diastolic volumes and the volume intercept. The volume intercept may be useful to gain insight into prognosis in heart failure. Clinical Trial Registration URL : https://www.clinicaltrials.gov/ . Unique identifier: NCT 00271154.

The use of pulse wave analysis may guide the provider in making choices about blood pressure treatment in prehypertensive or hypertensive patients. However, there is little clinical guidance on how to interpret and use pulse wave analysis data in the management of these patients. A panel of clinical researchers and clinicians who study and clinically use pulse wave analysis was assembled to discuss strategies for using pulse wave analysis in the clinical encounter. This manuscript presents an approach to the clinical application of pulse waveform analysis, how to interpret central pressure waveforms, and how to use existing knowledge about the pharmacodynamic effect of antihypertensive drug classes in combination with brachial and central pressure profiles in clinical practice. The discussion was supplemented by case‐based examples provided by panel members, which the authors hope will provoke discussion on how to understand and incorporate pulse wave analysis into clinical practice.

Background The utility of longitudinal, circumferential, and radial strain and strain rate in determining prognosis in chronic heart failure is not well established. Methods and Results In 416 patients with chronic systolic heart failure, we performed speckle‐tracking analyses of left ventricular longitudinal, circumferential, and radial strain and strain rate on archived echocardiography images (30 frames per second). Cox regression models were used to determine the associations between strain and strain rate and risk of all‐cause mortality, cardiac transplantation, and ventricular‐assist device placement. The area under the time‐dependent ROC curve ( AUC ) was also calculated at 1 year and 5 years. Over a maximum follow‐up of 8.9 years, there were 138 events (33.2%). In unadjusted models, all strain and strain rate parameters were associated with adverse outcomes ( P <0.001). In multivariable models, all parameters with the exception of radial strain rate ( P =0.11) remained independently associated, with patients in the lowest tertile of strain or strain rate parameter having a ≈2‐fold increased risk of adverse outcomes compared with the reference group ( P <0.05). Addition of strain to ejection fraction ( EF ) led to a significantly improved AUC at 1 year (0.697 versus 0.633, P =0.032) and 5 years (0.700 versus 0.638, P =0.001). In contrast, strain rate did not provide incremental prognostic value to EF alone. Conclusions Longitudinal and circumferential strain and strain rate, and radial strain are associated with chronic heart failure prognosis. Strain provides incremental value to EF in the prediction of adverse outcomes, and with additional study may be a clinically relevant prognostic tool.