The Cardiac Amyloidosis Registry Study (CARS): Rationale, Design and Methodology.

BACKGROUND: CARS (Cardiac Amyloidosis Registry Study) is a multicenter registry established in 2019 that includes patients with transthyretin (ATTR, wild-type and variant) and light chain (AL) cardiac amyloidosis (CA) evaluated at major amyloidosis centers between 1997 and 2025. CARS aims to describe the natural history of CA with attention to clinical and diagnostic variables at the time of diagnosis, real-world treatment patterns, and associated outcomes of patients in a diverse cohort that is more representative of the at-risk population than that described in CA clinical trials. METHODS AND RESULTS: This article describes the design and methodology of CARS, including procedures for data collection and preliminary results. As of February 2023, 20 centers in the United States enrolled 1415 patients, including 1155 (82%) with ATTR and 260 (18%) with AL CA. Among those with ATTR, wild-type is the most common ATTR (71%), and most of the 305 patients with variant ATTR have the p.V142I mutation (68%). A quarter of the total population identifies as Black. More individuals with AL are female (39%) compared to those with ATTR (13%). CONCLUSIONS: CARS will answer crucial clinical questions about CA natural history and permit comparison of different therapeutics not possible through current clinical trials. Future international collaboration will further strengthen the validity of observations of this increasingly recognized condition.

Myocardial Gene Expression Signatures in Human Heart Failure With Preserved Ejection Fraction.

BACKGROUND: Heart failure (HF) with preserved ejection fraction (HFpEF) constitutes half of all HF but lacks effective therapy. Understanding of its myocardial biology remains limited because of a paucity of heart tissue molecular analysis. METHODS: We performed RNA sequencing on right ventricular septal endomyocardial biopsies prospectively obtained from patients meeting consensus criteria for HFpEF (n=41) contrasted with right ventricular septal tissue from patients with HF with reduced ejection fraction (HFrEF, n=30) and donor controls (n=24). Principal component analysis and hierarchical clustering tested for transcriptomic distinctiveness between groups, effect of comorbidities, and differential gene expression with pathway enrichment contrasted HF groups and donor controls. Within HFpEF, non-negative matrix factorization and weighted gene coexpression analysis identified molecular subgroups, and the resulting clusters were correlated with hemodynamic and clinical data. RESULTS: Patients with HFpEF were more often women (59%), African American (68%), obese (median body mass index 41), and hypertensive (98%), with clinical HF characterized by 65% New York Heart Association Class III or IV, nearly all on a loop diuretic, and 70% with a HF hospitalization in the previous year. Principal component analysis separated HFpEF from HFrEF and donor controls with minimal overlap, and this persisted after adjusting for primary comorbidities: body mass index, sex, age, diabetes, and renal function. Hierarchical clustering confirmed group separation. Nearly half the significantly altered genes in HFpEF versus donor controls (1882 up, 2593 down) changed in the same direction in HFrEF; however, 5745 genes were uniquely altered between HF groups. Compared with controls, uniquely upregulated genes in HFpEF were enriched in mitochondrial adenosine triphosphate synthesis/electron transport, pathways downregulated in HFrEF. HFpEF-specific downregulated genes engaged endoplasmic reticulum stress, autophagy, and angiogenesis. Body mass index differences largely accounted for HFpEF upregulated genes, whereas neither this nor broader comorbidity adjustment altered pathways enriched in downregulated genes. Non-negative matrix factorization identified 3 HFpEF transcriptomic subgroups with distinctive pathways and clinical correlates, including a group closest to HFrEF with higher mortality, and a mostly female group with smaller hearts and proinflammatory signaling. These groupings remained after sex adjustment. Weighted gene coexpression analysis yielded analogous gene clusters and clinical groupings. CONCLUSIONS: HFpEF exhibits distinctive broad transcriptomic signatures and molecular subgroupings with particular clinical features and outcomes. The data reveal new signaling targets to consider for precision therapeutics.

A Stepwise Guide to the Diagnosis and Treatment of Heart Failure With Preserved Ejection Fraction.

Heart failure with preserved ejection fraction (HFpEF) is a growing epidemic owing to an increasingly obese and aging patient population. Making the diagnosis of HFpEF is often challenging because patients frequently have multiple comorbidities and alternative reasons for dyspnea and exercise intolerance, symptoms that are hallmark to the disease. Additionally, a universal diagnostic algorithm and definition of HFpEF is lacking. The treatment of HFpEF has been equally challenging, as there remain exceedingly few therapies show to improve survival in HFpEF and thus management to date has focused on intensive optimization of HFpEF risk factors. In this review, we highlight a stepwise approach to the diagnosis and treatment of HFpEF including (1) how to establish a clinical diagnosis of HFpEF, (2) when to refer for invasive diagnostic testing, (3) current treatment approaches to HFpEF including pharmacologic, nonpharmacologic, and risk factor modification interventions, and (4) when to refer to a dedicated HFpEF center or advanced heart failure specialist. With this systematic stepwise approach to HFpEF diagnosis and management, we aim to improve accurate diagnosis of the disease as well as raise awareness of available therapeutic options for this challenging patient population.

Under-Enrollment of Obese Heart Failure with Preserved Ejection Fraction Patients in Major HFpEF Clinical Trials.

BACKGROUND: Therapy for heart failure with preserved ejection fraction (HFpEF) remains an unmet need with lack of a consensus definition of HFpEF for inclusion into clinical trials. We evaluated whether hemodynamically characterized patients from a HFpEF referral center met inclusion criteria for 4 major HFpEF trials. METHODS AND RESULTS: Patients were assessed for theoretical inclusion into 4 major clinical trials (I-PRESERVE, RELAX, TOPCAT, and PARAGON-HF). Clinical, echocardiographic and hemodynamic characteristics and cardiovascular outcomes were compared between patients who met the inclusion criteria vs those who did not for each trial. Of 131 patients with HFpEF, 23% of patients met the enrollment criteria for I-PRESERVE, 38% for RELAX, 18% for TOPCAT, and 13% for PARAGON-HF. The top criteria that excluded patients included low natriuretic peptide level, obesity, uncontrolled hypertension, young age, and low hemoglobin. There was no difference in the probability of HF hospitalization or death in patients included or excluded into each clinical trial. CONCLUSIONS: In a cohort with hemodynamic evidence of HFpEF, a low proportion of patients met inclusion criteria for major HFpEF clinical trials, with no difference in outcomes in patients who did or did not meet inclusion criteria. Given relative the lack of proven therapies in HFpEF, consideration should be given to modifying clinical trial enrollment criteria to better represent contemporary patients with HFpEF in future clinical trials.

Management of heart failure in cardiac amyloidosis using an ambulatory diuresis clinic.

BACKGROUND: Recurrent congestion in cardiac amyloidosis (CA) remains a management challenge, often requiring high dose diuretics and frequent hospitalizations. Innovative outpatient strategies are needed to effectively manage heart failure (HF) in patients with CA. Ambulatory diuresis has not been well studied in restrictive cardiomyopathy. Therefore, we aimed to examine the outcomes of an ambulatory diuresis clinic in the management of congestion related to CA. METHODS AND RESULTS: We retrospectively studied patients with CA seen in an outpatient HF disease management clinic for (1) safety outcomes of ambulatory intravenous (IV) diuresis and (2) health care utilization. Forty-four patients with CA were seen in the clinic a total of 203 times over 6 months. Oral diuretics were titrated at 96 (47%) visits. IV diuretics were administered at 56 (28%) visits to 17 patients. There were no episodes of severe acute kidney injury or symptomatic hypotension. There was a significant decrease in emergency department and inpatient visits and associated charges after index visit to the clinic. The proportion of days hospitalized per 1000 patient days of follow-up decreased as early as 30 days (147.3 vs 18.1/1000 patient days of follow-up, P< .001) and persisted through 180 days (33.6 vs 22.9/1000 patient days of follow-up, P< .001) pre- vs post-index visit to the clinic. CONCLUSIONS: We demonstrate the feasibility of ambulatory IV diuresis in patients with CA. Our findings also suggest that use of a HF disease management clinic may reduce acute care utilization in patients with CA. Leveraging multidisciplinary outpatient HF clinics may be an effective alternative to hospitalization in patients with HF due to CA, a population who otherwise carries a poor prognosis and contributes to high health care burden.

Advances in the diagnosis and treatment of transthyretin amyloid cardiomyopathy.

Transthyretin amyloid cardiomyopathy (ATTR-CM) is an underrecognized cause of heart failure (HF). ATTR-CM can lead to a number of cardiovascular manifestations including HF, rhythm disturbances, and valvular disease that ultimately limit quality of life and prognosis. Due to advances in diagnostic modalities and therapeutic options, the prevalence of ATTR-CM is rising. There are several classes of medications under active investigation, though most therapies are most efficacious if instituted early on in the disease course. As such, early clinical recognition and prompt diagnosis are crucial to improving disease related outcomes. In this review, we highlight clinical manifestations of ATTR-CM as well as contemporary diagnostic and treatment approaches to the disease.

Coexistence of Light Chain and Transthyretin Cardiac Amyloidosis.

Although most patients with cardiac amyloidosis are diagnosed with either light chain (AL) or transthyretin (ATTR) disease, coexisting amyloid subtypes can occur. We present three cases of coexisting AL and ATTR cardiac amyloidosis and demonstrate the importance of clinical history and endomyocardial biopsy in diagnosis of this rare entity.

Race and Socioeconomic Status Impact Diagnosis and Clinical Outcomes in Transthyretin Cardiac Amyloidosis.

Background: Transthyretin amyloid cardiomyopathy (ATTR-CM) is associated with significant mortality. The Val122Ile variant, highly prevalent in Black patients, portends poorer survival compared with other ATTR-CM subtypes. Although Val122Ile is biologically more aggressive, the contribution of race and socioeconomic status (SES) to disease outcomes in patients with ATTR-CM is undefined. Objectives: The aim of this study was to evaluate the impact of race and SES on clinical outcomes in patients with ATTR-CM. Methods: Patients with ATTR-CM who received care at Johns Hopkins Hospital between 2006 and 2022 were included. SES was assessed using area deprivation index (ADI). Associations of race and ADI with heart failure (HF) hospitalization and/or death were measured using multivariable logistic or Cox proportional hazards models. Results: Of 282 patients, 225 (80%) were men, and 129 (46%) were Black. Black vs White patients disproportionately constituted the highest ADI (most deprived) category (66% vs 28%; P = 0.004), and Black patients were more likely to have HF hospitalization or death over 5 years compared with White patients (log-rank P < 0.001). Among those with ADI >25, Black patients had a significantly greater hazard of HF hospitalization or death compared with White patients, independent of disease stage at diagnosis (HR: 2.77; 95% CI: 1.45-5.32; P = 0.002). Conclusions: Black patients with low SES may be at greater risk for underdiagnosis and adverse outcomes compared with White patients. Ongoing efforts are needed to improve outcomes in this subset of patients with ATTR-CM.

Phenotypes Associated With the Val122Ile, Leu58His, and Late-Onset Val30Met Variants in Patients With Hereditary Transthyretin Amyloidosis.

BACKGROUND AND OBJECTIVES: Hereditary transthyretin amyloidosis (hATTR) is a rare autosomal dominant systemic disease with variable penetrance and heterogeneous clinical presentation. Several effective treatments can reduce mortality and disability, though diagnosis remains challenging, especially in the United States where disease is nonendemic. Our aim is to describe the neurologic and cardiac characteristics of common US ATTR variants V122I, L58H, and late-onset V30M at presentation. METHODS: We conducted a retrospective case series of patients with a new diagnosis of ATTRv between January 2008 and January 2020 to characterize features of prominent US variants. The neurologic (examination, EMG, and skin biopsy), cardiac (echo), and laboratory assessments (pro b-type natriuretic peptide [proBNP] and reversible neuropathy screens) are described. RESULTS: A total of 56 patients with treatment-naïve ATTRv with symptoms/signs of peripheral neuropathy (PN) or cardiomyopathy and confirmatory genetic testing presenting with Val122Ile (N = 31), late-onset Val30Met (N = 12), and Leu58His ATTRv (N = 13) were included. The age at onset and sex distributions were similar (V122I: 71.5 ± 8.0, V30M: 64.8 ± 2.6, and L58H: 62.4 ± 9.8 years; 26, 25, 31% female). Only 10% of patients with V122I and 17% of patients with V30M were aware of an ATTRv family history, while 69% of patients with L58H were aware. PN was present in all 3 variants at diagnosis (90%, 100%, and 100%), though neurologic impairment scores differed: V122I: 22 ± 16, V30M: 61 ± 31, and L58H: 57 ± 25. Most points (deficits) were attributed to loss of strength. Carpal tunnel syndrome (CTS) and a positive Romberg sign were common across all groups (V122I: 97%, 39%; V30M: 58%, 58%; and L58H: 77%, 77%). ProBNP levels and interventricular septum thickness were highest among patients with V122I (5,939 ± 962 pg/mL, 1.70 ± 0.29 cm), followed by V30M (796 ± 970 pg/mL, 1.42 ± 0.38 cm) and L58H (404 ± 677 pg/mL, 1.23 ± 0.36 cm). Atrial fibrillation was present among 39% of cases with V122I and only 8% of cases with V30M and L58H. Gastrointestinal symptoms were rare (6%) among patients with V122I and common in patients with V30M (42%) and L58H (54%). DISCUSSION: Important clinical differences exist between ATTRv genotypes. While V122I is perceived to be a cardiac disease, PN is common and clinically relevant. Most patients with V30M and V122I were diagnosed de novo and therefore require clinical suspicion for diagnosis. A history of CTS and a positive Romberg sign are helpful diagnostic clues.

Multimodality Imaging in the Evaluation and Prognostication of Cardiac Amyloidosis.

Cardiac amyloidosis (CA) is an infiltrative cardiomyopathy resulting from deposition of misfolded immunoglobulin light chains (AL-CA) or transthyretin (ATTR-CA) proteins in the myocardium. Survival varies between the different subtypes of amyloidosis and degree of cardiac involvement, but accurate diagnosis is essential to ensure initiation of therapeutic interventions that may slow or potentially prevent morbidity and mortality in these patients. As there are now effective treatment options for CA, identifying underlying disease pathogenesis is crucial and can be guided by multimodality imaging techniques such as echocardiography, magnetic resonance imaging, and nuclear scanning modalities. However, as use of cardiac imaging is becoming more widespread, understanding optimal applications and potential shortcomings is increasingly important. Additionally, certain imaging modalities can provide prognostic information and may affect treatment planning. In patients whom imaging remains non-diagnostic, tissue biopsy, specifically endomyocardial biopsy, continues to play an essential role and can facilitate accurate and timely diagnosis such that appropriate treatment can be started. In this review, we examine the multimodality imaging approach to the diagnosis of CA with particular emphasis on the prognostic utility and limitations of each imaging modality. We also discuss how imaging can guide the decision to pursue tissue biopsy for timely diagnosis of CA.

Large Pleural Effusion: A Pitfall in the Quantitation of 99m Tc-PYP Imaging for ATTR Cardiac Amyloidosis.

ABSTRACT: Transthyretin cardiac amyloidosis (ATTR and ATTRv) is an underrecognized cause of heart failure that results from myocardial deposition of misfolded protein (TTR or prealbumin). The diagnosis can be confirmed by uptake of 99m Tc-pyrophosphate ( 99m Tc-PYP) in the heart with serologic studies to rule out light chain disease. We present the case of a 70-year-old woman who underwent a 99m Tc-PYP scan. The patient had a large right-sided pleural effusion that lowered counts in the right chest on planar imaging, interfered with ratio-based grading of PYP uptake, and highlighted the importance of obtaining SPECT/CT for problem-solving in cases where uptake ratios may be spurious.

Atrial fibrillation is an independent risk factor for heart failure hospitalization in heart failure with preserved ejection fraction.

AIMS: Atrial fibrillation (AF) is a common comorbid condition in heart failure with preserved ejection fraction (HFpEF). The effect of AF on heart failure (HF) exacerbation in HFpEF has not been well described. This study investigated how AF modifies the clinical trajectory of HFpEF patients after hospitalization for decompensated HF. METHODS AND RESULTS: We stratified HFpEF subjects by AF diagnosis and performed longitudinal analysis to compare risk for HF hospitalization after index hospitalization for decompensated HF. All-cause mortality, 30 day all-cause readmissions, and response to inpatient diuresis were also evaluated. Of 90 subjects enrolled, 35.6% (n = 32) had AF. Subjects with AF were older (72.5 vs. 60.5 years; P < 0.01), more often male (46.9% vs. 24.1%; P = 0.03), and had greater left atrial diameter (4.9 vs. 3.8 cm; P < 0.01) compared with those without AF. Subjects with AF had a higher risk for HF hospitalization than their counterparts without AF (P = 0.02); this relationship remained significant following multivariable competing risk regression with propensity score weighting (hazard ratio 2.53, P = 0.04 and hazard ratio 2.91, P = 0.04, with overlap and inverse probability weighting, respectively). Although having AF appeared to increase the risk of all-cause hospital readmission within 30 days of discharge (37.5% vs. 17.5%; P = 0.036), this relationship failed to remain significant following propensity score adjustment for clinical covariates. CONCLUSIONS: Atrial fibrillation is an independent risk factor for HF rehospitalization in HFpEF. Further understanding of the interplay between AF and HFpEF will be critical to guide the selection of appropriate rhythm management strategies in this population.

Heart transplantation strategies in arrhythmogenic right ventricular cardiomyopathy: a tertiary ARVC centre experience.

AIMS: End-stage heart failure necessitating evaluation for heart transplantation is increasingly recognized in arrhythmogenic right ventricular cardiomyopathy (ARVC). These patients present unique challenges in pre-transplant and peri-transplant management given their predominantly right ventricular (RV) failure and propensity for ventricular arrhythmias. We sought to utilize a tertiary ARVC referral and heart transplant centre experience to describe management of a series of patients with ARVC undergoing heart transplantation at our centre. METHODS AND RESULTS: We queried the Johns Hopkins ARVC Registry for all patients who underwent heart transplantation and further studied the subset undergoing transplantation at the Johns Hopkins Hospital. Patient demographics, clinical characteristics, and pre-transplant clinical course were obtained from the registry and electronic medical records. Of the 532 patients in the ARVC Registry, 63 (12%) underwent heart transplantation. Nine (six male) of these patients both had known ARVC prior to transplant and were transplanted at Johns Hopkins Hospital between 2006 and 2020 at a mean age of 42 ± 14 years old. Pathogenic ARVC genetic variants were identified in six (67%) patients, all of whom had variants in the plakophilin-2 (PKP2) gene. RV failure was universal with median right atrial to pulmonary capillary wedge pressure (RA/PCWP) ratio of 1.4 [interquartile range (IQR) 1.2-1.5] and median right ventricular stroke work index (RVSWI) of 0 g·m/m2 /beat (IQR 0-0.3). Six had a history of catheter ablation for ventricular arrhythmia with five of the six having at least three ablations. Transplant evaluation was initiated an average of 344 ± 407 days after first developing heart failure symptoms. The most common bridge to transplant support included inotropes (n = 3) and extracorporeal membrane oxygenation (ECMO) (n = 2). Contraindication to inotropes or mechanical support was common due to ventricular arrhythmia and RV predominant cardiomyopathy. CONCLUSIONS: Heart transplantation is a curative treatment for ARVC, but due to frequent ventricular arrhythmias and RV predominant pathology, patients require unique considerations in regard to timing of evaluation, haemodynamic support options, and wait listing qualification.

Anomalous Origin of the Right Coronary Artery Causing Myocardial Ischemia: A Case for a Multimodality Imaging Approach.

A 46-year-old man was admitted with non-ST elevation myocardial infarction and newly diagnosed acutely decompensated heart failure. Echocardiogram demonstrated left ventricular ejection fraction of 30% with basal inferior and inferolateral akinesis. Coronary angiography showed mild diffuse coronary artery disease and an anomalous right coronary artery arising from the left coronary cusp. Further imaging was consistent with ischemia in the right coronary distribution. Etiology of ischemia was thought to be the anomalous right coronary artery, and surgical unroofing of the right coronary ostium was performed. Here, we report a multimodality imaging approach, including cardiac magnetic resonance, cardiac computed tomographic angiography, and single-photon emission computed tomography, to support the diagnosis and management of a patient with anomalous right coronary artery arising from the left coronary cusp.

Highest Obesity Category Associated With Largest Decrease in N-Terminal Pro-B-Type Natriuretic Peptide in Patients Hospitalized With Heart Failure With Preserved Ejection Fraction.

Background Heart failure with preserved ejection fraction (HFpEF) constitutes half of hospitalized heart failure cases and is commonly associated with obesity. The role of natriuretic peptide levels in hospitalized obese patients with HFpEF, however, is not well defined. We sought to evaluate change in NT-proBNP (N-terminal pro-B-type natriuretic peptide) levels by obesity category and related clinical outcomes in patients with HFpEF hospitalized for acute heart failure. Methods and Results A total of 89 patients with HFpEF hospitalized with acute decompensated heart failure were stratified into 3 obesity categories: nonobese (body mass index [BMI] <30.0 kg/m2, 19%), obese (BMI 30.0-39.9 kg/m2, 29%), and severely obese (BMI ≥40.0 kg/m2, 52%), and compared for percent change in NT-proBNP during hospitalization and clinical outcomes. Clinical characteristics were compared between patients with normal NT-proBNP (≤125 pg/mL) and elevated NT-proBNP. Admission NT-proBNP was inversely related to BMI category (nonobese, 2607 pg/mL [interquartile range, IQR: 2112-5703]; obese, 1725 pg/mL [IQR: 889-3900]; and severely obese, 770.5 pg/mL [IQR: 128-1268]; P<0.01). Severely obese patients had the largest percent change in NT-proBNP with diuresis (-64.8% [95% CI, -85.4 to -38.9] versus obese -40.4% [95% CI, -74.3 to -12.0] versus nonobese -46.9% [95% CI, -57.8 to -37.4]; P=0.03). Nonobese and obese patients had significantly worse 1-year survival compared with severely obese patients (63% versus 76% versus 95%, respectively; P<0.01). Patients with normal NT-proBNP (13%) were younger, with higher BMI, less atrial fibrillation, and less structural heart disease than those with elevated NT-proBNP. Conclusions In hospitalized patients with HFpEF, NT-proBNP was inversely related to BMI with the largest decrease in NT-proBNP seen in the highest obesity category. These findings have implications for the role of NT-proBNP in the diagnosis and assessment of treatment response in obese patients with HFpEF.

Dual-Organ Transplantation in a Woman With Right Ventricular Failure Secondary to Arrhythmogenic Right Ventricular Cardiomyopathy.

We report a case of a woman with arrhythmogenic right ventricular cardiomyopathy (ARVC) who presented with severe right-sided heart failure and cardiac cirrhosis that mandated heart-liver transplantation. This case highlights an emerging sex-based difference in ARVC where female sex is associated with a higher risk of heart failure than in male patients with ARVC. (Level of Difficulty: Advanced.).

Crossing the Bridge to Heart Transplantation: Biventricular Impella to Support an Unstable LVAD Patient.

We report the first case of a patient with a durable left ventricular assist device admitted with cardiogenic shock and managed with biventricular Impella support as a successful bridge to heart transplantation. (Level of Difficulty: Advanced.).

Endomyocardial Biopsy Characterization of Heart Failure With Preserved Ejection Fraction and Prevalence of Cardiac Amyloidosis.

OBJECTIVES: This study prospectively evaluated endomyocardial biopsies in patients with heart failure with preserved ejection fraction (HFpEF) to identify histopathologic phenotypes and their association with clinical characteristics. BACKGROUND: Myocardial tissue analysis from a prospectively defined HFpEF cohort reflecting contemporary comorbidities is lacking. METHODS: Patients with HFpEF (EF ≥50%) referred to the Johns Hopkins HFpEF Clinic between August 2014 and September 2018 were enrolled for right heart catheterization and endomyocardial biopsy. Clinical features, echocardiography, hemodynamics, and tissue histology were determined and compared with controls (unused donor hearts) and HF with reduced EF (HFrEF). RESULTS: Of the 108 patients enrolled, median age was 66 years (25th to 75th percentile: 57 to 74 years), 61% were women, 57% were African American, 62% had a previous HF hospitalization, median systolic blood pressure was 141 mm Hg (25th to 75th percentile: 125 to 162 mm Hg), body mass index (BMI) was 37 kg/m2 (25th to 75th percentile: 32 to 45 kg/m2), and 97% were on a loop diuretic. Myocardial fibrosis and myocyte hypertrophy were often present (93% and 88%, respectively); however, mild in 71% with fibrosis and in 52% with hypertrophy. Monocyte infiltration (CD68+ cells/mm2) was greater in patients with HFpEF versus controls (60.4 cells/mm2 [25th to 75th percentile: 36.8 to 97.8] vs. 32.1 cells/mm2 [25th to 75th percentile: 22.3 to 59.2]; p = 0.02) and correlated with age and renal disease. Cardiac amyloidosis (CA) was diagnosed in 15 (14%) patients (HFpEF-CA: 7 patients with wild-type transthyretin amyloidosis [ATTR], 4 patients with hereditary ATTR, 3 patients with light-chain amyloidosis, and 1 patient with AA (secondary) amyloidosis), of which 7 cases were unsuspected. Patients with HFpEF-CA were older, with lower BMI, higher left ventricular mass index, and higher N-terminal pro-B-type natriuretic peptide and troponin I levels. CONCLUSIONS: In this large, prospective myocardial tissue analysis of HFpEF, myocardial fibrosis and hypertrophy were common, CD68+ inflammation was increased, and CA prevalence was 14%. Tissue analysis in HFpEF might improve precision therapies by identifying relevant myocardial mechanisms.