Petr Jarolim

BACKGROUND: Some, but not all, patients with heart failure (HF) develop pulmonary vascular disease (PVD), which contributes to poor prognosis. Mechanisms leading to PVD in HF are poorly understood. We aimed to analyze transpulmonary gradients of proteins consumed or elaborated across the lungs to identify mediators of PVD by unbiased proteomics. METHODS: Overall, 21 controls and 160 patients with HF with reduced ejection fraction underwent pulmonary artery catheterization with blood sampling from postcapillary (wedged balloon) and precapillary (unwedged) position to obtain transpulmonary gradients. The samples from controls and HF from the highest (Q4, n=40) and lowest quartile (Q1, n=40) of pulmonary vascular resistance (PVR) were analyzed using the proteomic proximity extension assay (Olink) of 275 proteins. Venous blood concentrations or transpulmonary gradients were analyzed to identify biomarkers or potential mediators of PVD. RESULTS: Comparison of Q1 and Q4 of PVR identified PSP-D (pulmonary surfactant-associated protein D) as a marker of PVD. Examination of gradients across the lungs in high PVR HF revealed significant uptake of 18 proteins, mostly associated with inflammation (chemokines, oncostatin-M, MMP9 [matrix metalloproteinase 9]) or with TGF (transforming growth factor)/activin pathway (GDF2 [growth differentiation factor 2]/BMP9 [bone morphogenic protein 9]), and release of 5 proteins, notably IL (interleukin) 6 and IL33. In contrast, these protein gradients were negligible in controls and low PVR patients with HF. Active pulmonary release of IL6 contributed to systemic elevation of IL6 and correlated with right ventricular function. CONCLUSIONS: The lungs of patients with HF with high PVR display abnormal uptake and release of proinflammatory cytokines from IL6/gp130 family (IL6, IL33, oncostatin-M), along with increased transpulmonary uptake of GDF2/BMP9. The study shows that proteins orchestrating inflammation or pulmonary vessel remodeling in group 1 pulmonary hypertension, are also operating in patients with PVD due to HF. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT06331208.

BACKGROUND: Hypertrophic cardiomyopathy (HCM) is a heterogeneous condition that can lead to atrial fibrillation, heart failure, and sudden cardiac death in many individuals but mild clinical impact in others. The mechanisms underlying this phenotypic heterogeneity are not well defined. The aim of this study was to use plasma proteomic profiling to help illuminate biomarkers that reflect or inform the heterogeneity observed in HCM. METHODS: The Olink antibody–based proteomic platform was used to measure plasma proteins in patients with genotype positive (sarcomeric) HCM participating in the HCM Registry. We assessed associations between plasma protein levels with clinical features, cardiac magnetic resonance imaging metrics, and the development of atrial fibrillation. RESULTS: We measured 275 proteins in 701 patients with sarcomeric HCM. There were associations between late gadolinium enhancement with proteins reflecting neurohormonal activation (NT-proBNP [N-terminal pro-B-type natriuretic peptide] and ACE2 [angiotensin-converting enzyme 2]). Metrics of left ventricular remodeling had novel associations with proteins involved in vascular development and homeostasis (vascular endothelial growth factor-D and TM [thrombomodulin]). Assessing clinical features, the European Society of Cardiology sudden cardiac death risk score was inversely associated with SCF (stem cell factor). Incident atrial fibrillation was associated with mediators of inflammation and fibrosis (MMP2 [matrix metalloproteinase 2] and SPON1 [spondin 1]). CONCLUSIONS: Proteomic profiling of sarcomeric HCM identified biomarkers associated with adverse imaging and clinical phenotypes. These circulating proteins are part of both established pathways, including neurohormonal activation and fibrosis, and less familiar pathways, including endothelial function and inflammatory proteins less well characterized in HCM. These findings highlight the value of plasma profiling to identify biomarkers of risk and to gain further insights into the pathophysiology of HCM.

Aims: We sought to characterize circulating protein biomarkers associated with cardiogenic shock (CS) using highly multiplex proteomic profiling. Methods and results: This analysis employed a cross-sectional case–control study design using a biorepository of patients admitted to a cardiac intensive care unit between 2017 and 2020. Cases were patients adjudicated to have CS, and controls were those presenting for cardiac critical care without shock, including subsets of patients with isolated hypotension or heart failure (HF). The Olink platform was used to analyse 359 biomarkers with Bonferroni correction. The analysis included 239 patients presenting for cardiac critical care (69 cases with CS, 170 non-shock controls). A total of 63 biomarkers (17.7%) were significantly associated with CS after Bonferroni correction compared with all controls. Of these, nine biomarkers remained significantly associated with CS when separately cross-validated in subsets of controls presenting with isolated hypotension and HF: cathepsin D, fibroblast growth factor (FGF)-21 and -23, growth differentiation factor (GDF)-15, insulin-like growth factor-binding protein-1, N-terminal pro-B-type natriuretic peptide, osteopontin, oncostatin-M-specific receptor subunit beta (OSMR), and soluble ST2 protein (sST2). Four biomarkers were identified as providing complementary information for CS diagnosis with development of a multi-marker model: sST2, FGF-23, CTSD, and GDF-15. Conclusion: In this pilot study of targeted proteomic profiling in CS, we identified nine biomarkers significantly associated with CS when cross-validated against non-shock controls including those with HF or isolated hypotension, illustrating the potential application of a targeted proteomic approach to identify novel candidates that may support the diagnosis of CS.

Incidence of COVID-19 has been associated with sociodemographic factors. We investigated variations in SARS-CoV-2 seroprevalence at sub-national levels in the Dominican Republic and assessed potential factors influencing variation in regional-level seroprevalence. Data were collected in a three-stage cross-sectional national serosurvey from June to October 2021. Seroprevalence of antibodies against the SARS-CoV-2 spike protein (anti-S) was estimated and adjusted for selection probability, age, and sex. Multilevel logistic regression was used to estimate the effect of covariates on seropositivity for anti-S and correlates of 80% protection (PT₈₀) against symptomatic infection for the ancestral and Delta strains. A total of 6683 participants from 134 clusters in all 10 regions were enrolled. Anti-S, PT80 for the ancestral and Delta strains odds ratio varied across regions, Enriquillo presented significant higher odds for all outcomes compared with Yuma. Compared to being unvaccinated, receiving ≥2 doses of COVID-19 vaccine was associated with a significantly higher odds of anti-S positivity (OR 85.94, [10.95–674.33]) and PT₈₀ for the ancestral (OR 4.78, [2.15–10.62]) and Delta strains (OR 3.08, [1.57–9.65]) nationally and also for each region. Our results can help inform regional-level public health response, such as strategies to increase vaccination coverage in areas with low population immunity against currently circulating strains.

Incidence of COVID-19 has been associated with sociodemographic factors. We investigated variations in SARS-CoV-2 seroprevalence at sub-national levels in the Dominican Republic and assessed potential factors influencing variation in regional-level seroprevalence. Data were collected in a three-stage cross-sectional national serosurvey from June to October 2021. Seroprevalence of antibodies against the SARS-CoV-2 spike protein (anti-S) was estimated and adjusted for selection probability, age, and sex. Multilevel logistic regression was used to estimate the effect of covariates on seropositivity for anti-S and correlates of 80% protection (PT80) against symptomatic infection for ancestral and Delta strains. A total of 6,683 participants from 134 clusters in all 10 regions were enrolled. Anti-S, PT80 for ancestral and Delta strains odds ratio varied across regions, Enriquillo presented significant higher odds for all outcomes compared with Yuma. Compared to unvaccinated, receiving ≥2doses of COVID-19 vaccine was associated with a significantly higher odds of anti-S positivity (OR 85.94, [10.95-674.33]), and PT80 for ancestral (OR 4.78, [2.15-10.62]) and Delta strains (OR 3.08, [1.57-9.65]) nationally, and also for each region. Our results can help inform regional-level public health response, such as strategies to increase vaccination coverage in areas with low population immunity against currently circulating strains.

Background: The hypocretin/orexin system has been shown to play a role in heart failure. Whether it also influences myocardial infarction (MI) outcomes is unknown. We evaluated the effect of the rs7767652 minor allele T associated with decreased transcription of the hypocretin/orexin receptor‐2 and circulating orexin A concentrations on mortality risk after MI. Methods and Results: Data from a single‐center, prospectively designed registry of consecutive patients hospitalized for MI at a large tertiary cardiology center were analyzed. Patients without previous history of MI or heart failure were included. A random population sample was used to compare allele frequencies in the general population. Out of 1009 patients (aged 64±12 years, 74.6% men) after MI, 6.1% were homozygotes (TT) and 39.4% heterozygotes (CT) for minor allele. Allele frequencies in the MI group did not differ from 1953 subjects from general population (χ ² P =0.62). At index hospitalization, MI size was the same, but ventricular fibrillation and the need for cardiopulmonary resuscitation were more prevalent in the TT allele variant. Among patients with ejection fraction ≤40% at discharge, the TT variant was associated with a lower increase in left ventricular ejection fraction during follow‐up ( P =0.03). During the 27‐month follow‐up, there was a statistically significant association of the TT variant with increased mortality risk (hazard ratio [HR], 2.83; P =0.001). Higher circulating orexin A was associated with a lower mortality risk (HR, 0.41; P <0.05). Conclusions: Attenuation of hypocretin/orexin signaling is associated with increased mortality risk after MI. This effect may be partially explained by the increased arrhythmic risk and the effect on the left ventricular systolic function recovery.

Interest in targeted screening programmes for atrial fibrillation (AF) has increased, yet the role of genetics in identifying patients at highest risk of developing AF is unclear. A total of 36,662 subjects without prior AF were analyzed from four TIMI trials. Subjects were divided into quintiles using a validated polygenic risk score (PRS) for AF. Clinical risk for AF was calculated using the CHARGE-AF model. Kaplan–Meier event rates, adjusted hazard ratios (HRs), C-indices, and net reclassification improvement were used to determine if the addition of the PRS improved prediction compared with clinical risk and N-terminal pro-B-type natriuretic peptide (NT-proBNP). Over 2.3 years, 1018 new AF cases developed. AF PRS predicted a significant risk gradient for AF with a 40% increased risk per 1-SD increase in PRS [HR: 1.40 (1.32–1.49); P < 0.001]. Those with high AF PRS (top 20%) were more than two-fold more likely to develop AF [HR 2.45 (1.99–3.03), P < 0.001] compared with low PRS (bottom 20%). Furthermore, PRS provided an additional gradient of risk stratification on top of the CHARGE-AF clinical risk score, ranging from a 3-year incidence of 1.3% in patients with low clinical and genetic risk to 8.7% in patients with high clinical and genetic risk. The subgroup of patients with high clinical risk, high PRS, and elevated NT-proBNP had an AF risk of 16.7% over 3 years. The C-index with the CHARGE-AF clinical risk score alone was 0.65, which improved to 0.67 (P < 0.001) with the addition of NT-proBNP, and increased further to 0.70 (P < 0.001) with the addition of the PRS. In patients with cardiovascular conditions, AF PRS is a strong independent predictor of incident AF that provides complementary predictive value when added to a validated clinical risk score and NT-proBNP. Classification of study population by genetic, clinical, and biomarker risk for atrial fibrillation (AF). PRS, polygenic risk score; CHARGE-AF, Cohorts for Heart and Aging Research in Genomic Epidemiology for Atrial Fibrillation (risk score including age, height, weight, systolic blood pressure, diastolic blood pressure, current tobacco use, antihypertensive medication use, diabetes, heart failure, and prior myocardial infarction). Rates of incident AF by genetic, clinical, and biomarker risk categories are shown.

Objectives: Poor phlebotomy technique can introduce pseudohyperkalemia without hemolysis, requiring additional workup and placing a significant burden on patients, clinical teams, and laboratories. Such preanalytical biases can be detected through systematic evaluation of potassium concentrations on a per-phlebotomist basis. We report our long-term experience with a potassium-based quality-of-service phlebotomy metric and its effects on resource utilization. Methods: Potassium monitoring and retraining of 26 full-time phlebotomists were piloted as a quality-of-service intervention. Changes in potassium concentrations and impact on resource utilization were assessed. An algorithm for data monitoring and phlebotomist feedback was developed, followed by institution-wide implementation. Results: Systematic intervention and retraining normalized K+ concentrations and lowered the percentage of venipunctures with K+ above 5.2 mmol/L, leading to a marked increase in phlebotomist compliance. This change resulted in resources savings of 13% to 100% for individual phlebotomists, reducing the total extra laboratory time required for repeat phlebotomies to determine hyperkalemia, mostly in the high-volume phlebotomist group. Conclusions: A quality-of-service algorithm that involved monitoring potassium concentrations on a per-phlebotomist basis with feedback and retraining contributed to a concrete, data-based quality improvement plan. The institution-wide implementation of this metric allowed for significant cost savings and a reduction in critical value alerts, directly affecting the quality of patient care.

Heart transplantation is the optimal therapy for patients with end-stage heart disease, but its long-term outcome remains inadequate. Recent studies have highlighted the importance of the melanocortin receptors (MCRs) in inflammation, but how MCRs regulate the balance between alloreactive T cells and Tregs, and whether they impact chronic heart transplant rejection, is unknown. Here, we found that Tregs express MC2R, and MC2R expression was highest among all MCRs by Tregs. Our data indicate that adrenocorticotropic hormone (ACTH), the sole ligand for MC2R, promoted the formation of Tregs by increasing the expression of IL-2Rα (CD25) in CD4 ⁺ T cells and activation of STAT5 in CD4 ⁺ CD25 ⁺ T cells. ACTH treatment also improved the survival of heart allografts and increased the formation of Tregs in CD28KO mice. ACTH treatment synergized with the tolerogenic effect of CTLA-4–Ig, resulting in long-term survival of heart allografts and an increase in intragraft Tregs. ACTH administration also demonstrated higher prolongation of heart allograft survival in transgenic mouse recipients with both complete KO and conditional KO of PI3Kγ in T cells. Finally, ACTH treatment reduced chronic rejection markedly. These data demonstrate that ACTH treatment improved heart transplant outcomes, and this effect correlated with an increase in Tregs.