Background: Recent trial data suggest that stratification of patients with heart failure with preserved ejection fraction (HFpEF) according to left ventricular ejection fraction (LVEF) provides a means for dissecting different treatment responses. However, the differential pathophysiologic considerations have rarely been described. Methods: This prospective, single-center study analyzed consecutive symptomatic patients with HFpEF diagnosed according to the 2016 European Society of Cardiology heart failure guidelines. Patients were grouped into LVEF 50% to 60% and LVEF >60% cohorts. All patients underwent cardiac magnetic resonance imaging. Transfemoral cardiac catheterization was performed to derive load-dependent and load-independent left ventricular (LV) properties on pressure–volume loop analyses. Results: Fifty-six patients with HFpEF were enrolled and divided into LVEF 50% to 60% (n=21) and LVEF >60% (n=35) cohorts. On cardiac magnetic resonance imaging, the LVEF >60% cohort showed lower LV end-diastolic volumes ( P =0.019) and end-systolic volumes ( P =0.001) than the LVEF 50% to 60% cohort; stroke volume ( P =0.821) did not differ between the cohorts. Extracellular volume fraction was higher in the LVEF 50% to 60% cohort than in the LVEF >60% cohort (0.332 versus 0.309; P =0.018). Pressure-volume loop analyses demonstrated higher baseline LV contractility (end-systolic elastance, 1.85 vs 1.33 mm Hg/mL; P 60% cohort. Ventriculo-arterial coupling (end-systolic elastance/arterial elastance) at rest was in the range of optimized stroke work in the LVEF >60% cohort but was impaired in the LVEF 50% to 60% cohort (1.01 versus 0.80; P =0.005). During handgrip exercise, patients with LVEF >60% had higher increases in end-systolic elastance (1.85 versus 0.82 mm Hg/mL; P =0.023), attenuated increases in indexed end-systolic volume (−1 versus 7 mL/m²; P 60% cohort ( P =0.007) under exertion. Conclusions: Patients with HFpEF in whom LVEF ranged from 50% to 60% demonstrated reduced contractility, impaired ventriculo-arterial coupling, and higher extracellular volume fraction. In contrast, patients with HFpEF and a LVEF >60% demonstrated a hypercontractile state with excessive LV afterload and diminished preload reserve. A LVEF-based stratification of patients with HFpEF identified distinct morphologic and pathophysiologic subphenotypes.
Background: Arterial stiffening contributes to hemodynamic derangements in heart failure with preserved ejection fraction (HFpEF). We sought to investigate the impact of renal denervation on pulsatile left ventricular loading in patients with HFpEF and hypertensive patients without heart failure (control). Methods: Patients underwent renal denervation for treatment of hypertension and were followed up at 3 months at a single center. A validated computer model of the arterial tree, noninvasive aortic flow curves, left ventricular volumes, and E/e′ as inputs were used to determine key parameters of left ventricular vascular load. Results: In comparison to controls (n=30), patients with HFpEF (n=30) demonstrated lower total arterial compliance (mean difference, −0.41 [95% CI, −0.72 to −0.10] mL/mm Hg), higher impedance of the proximal aorta (Zc: 0.02; 0.01 to 0.04 mHg·s/mL), premature wave reflections (shorter backward wave transit time normalized to ejection time: −3.5; −6.5% to −0.5%), and higher wave reflection magnitude (reflection coefficient: 7.3; 2.8% to 11.9%). Overall, daytime systolic (−9.2; −12.2 to −6.2 mm Hg) and diastolic blood pressures (−5.9; −7.6 to −4.1 mm Hg) as well as blood pressure variability (−2.0; −3.0 to −0.9 mm Hg) decreased after renal denervation. In patients with HFpEF, total arterial compliance (0.42; 0.17 to 0.67 mL/mm Hg) and backward transit time normalized to ejection time (1.7; 0.4% to 3.0%) increased; Zc (−0.01; −0.02 to −0.01 mm Hg·s/mL) and reflection coefficient (−2.6; −5.0% to −0.3%) decreased after renal denervation. This was accompanied by a symptomatic improvement in patients with HFpEF. Conclusion: HFpEF is characterized by heightened aortic stiffness and unfavorable pulsatile left ventricular load. These abnormalities are partly normalized after renal denervation.
BACKGROUND: Activation of the immune system contributes to cardiovascular diseases. The role of human-specific long noncoding RNAs in cardioimmunology is poorly understood. METHODS: Single-cell sequencing in peripheral blood mononuclear cells revealed a novel human-specific long noncoding RNA called HEAT4 (heart failure–associated transcript 4). HEAT4 expression was assessed in several in vitro and ex vivo models of immune cell activation, as well as in the blood of patients with heart failure (HF), acute myocardial infarction, or cardiogenic shock. The transcriptional regulation of HEAT4 was verified through cytokine treatment and single-cell sequencing. Loss-of-function and gain-of-function studies and multiple RNA–protein interaction assays uncovered a mechanistic role of HEAT4 in the monocyte anti-inflammatory gene program. HEAT4 expression and function was characterized in a vascular injury model in NOD.CB17-Prkdc scid/Rj mice. RESULTS: HEAT4 expression was increased in the blood of patients with HF, acute myocardial infarction, or cardiogenic shock. HEAT4 levels distinguished patients with HF from people without HF and predicted all-cause mortality in a cohort of patients with HF over 7 years of follow-up. Monocytes, particularly anti-inflammatory CD16 + monocytes, which are increased in patients with HF, are the primary source of HEAT4 expression in the blood. HEAT4 is transcriptionally activated by treatment with anti-inflammatory interleukin-10. HEAT4 activates anti-inflammatory and inhibits proinflammatory gene expression. Increased HEAT4 levels result in a shift toward more CD16 + monocytes. HEAT4 binds to S100A9, causing a monocyte subtype switch, thereby reducing inflammation. As a result, HEAT4 improves endothelial barrier integrity during inflammation and promotes vascular healing after injury in mice. CONCLUSIONS: These results characterize a novel endogenous anti-inflammatory pathway that involves the conversion of monocyte subtypes into anti-inflammatory CD16 + monocytes. The data identify a novel function for the class of long noncoding RNAs by preventing protein secretion and suggest long noncoding RNAs as potential targets for interventions in the field of cardioimmunology.
BACKGROUND: Heart failure with preserved ejection fraction (HFpEF) is a heterogeneous clinical picture that is closely related to extracardiac comorbidities such as obesity, hypertension, and diabetes and is associated with chronic, low-grade systemic inflammation. Previous studies on myocardial biopsies of patients with HFpEF showed intramyocardial inflammatory activity, suggesting that the inflammatory processes in HFpEF are predominantly systemic and exhibit compartment-specific patterns. METHODS: We performed single-cell RNA sequencing of peripheral blood mononuclear cells of patients with HFpEF (n=6), patients with heart failure with reduced ejection fraction (HFrEF, n=8), and healthy controls (n=7), taking obesity status into account. For validation, bulk RNA sequencing was performed on whole blood samples. In parallel, the systemic immune cell response was investigated in an HFpEF mouse model (induced by a high-fat diet plus Nω -nitro-L-arginine methyl ester hydrochloride [L-NAME]), with one group additionally administered the anti-inflammatory agent nitro-oleic acid (NO 2 -OA). RESULTS: Analysis of human peripheral blood mononuclear cells revealed an HFpEF-specific inflammatory fingerprint, which manifested in obesity-related increased expression of cytokine signaling genes (eg, CCL2 and TNF ) and obesity-independent increases in mitochondrial-associated activity. In the mouse model, HFpEF animals showed a comparable increase in inflammatory markers, with treatment with nitro-oleic acid leading to a partial normalization of immunologic signatures and a significant improvement in diastolic function. CONCLUSIONS: Our results demonstrate that the immune cells of patients with HFpEF are characterized by a distinct transcriptional immune signature that differs from that of patients with HFrEF analyzed in this study. The conserved immunologic signatures between the human and murine data sets analyzed here, and the beneficial effect of nitro-oleic acid in the preclinical model induced by high-fat diet and L-NAME, provide translational insights and generate hypotheses for personalized interventions in HFpEF.
Osteoporosis is a common metabolic disorder diagnosed by lower bone density and higher risk of fracture. Fragility fractures because of osteoporosis are associated with high mortality rate. Deep understanding of fracture healing in osteoporosis is important for successful treatment. Therefore, the FDA approved the use of small and large animal models for preclinical testing. This study investigated the clinical relevance of a fracture defect model in the iliac crest of the osteoporotic sheep model and its several advantages over other models. The osteoporosis was achieved using ovariectomy (OVX) in combination with diet deficiency (OVXD) and steroid administration (OVXDS). Fluorochrome was injected to examine the rate of bone remodelling and bone mineralization. The defect areas were collected and embedded in paraffin and polymethyl metha acrylate (PMMA) for histological staining. OVXDS showed significantly lower bone mineral density (BMD) and bone mineral content (BMC) at all time points. Furthermore, variations in healing patterns were noticed, while the control, OVX and OVXD showed complete healing after 8 months. Bone quality was affected mostly in the OVXDS group showing irregular trabecular network, lower cortical bone thickness and higher cartilaginous tissue at 8 months. The mineral deposition rate showed a declining pattern in the control, OVX, and OVXD from 5 months to 8 months. One the contrary, the OVXDS group showed an incremental pattern from 5 months to 8 months. The defect zone in osteoporotic animals showed impaired healing and the control showed complete healing after 8 months. This unique established model serves as a dual-purpose model and has several advantages: no intraoperative and postoperative complications, no need for fixation methods for biomaterial testing, and reduction in animal numbers, which comply with 3R principles by using the same animal at two different time points.
15 August 2023 in Journal of the American Heart Association
BACKGROUND: Renal denervation has proven its efficacy to lower blood pressure in comparison to sham treatment in recent randomized clinical trials. Although there is a large body of evidence for the durability and safety of radiofrequency‐based renal denervation, there are a paucity of data for endovascular ultrasound–based renal denervation (uRDN). We aimed to assess the long‐term efficacy and safety of uRDN in a single‐center cohort of patients. METHODS AND RESULTS: Data from 2 previous studies on uRDN were pooled. Ambulatory 24‐hour blood pressure measurements were taken before as well as 3, 6, 12, and 24 months after treatment with uRDN. A total of 130 patients (mean age 63±9 years, 24% women) underwent uRDN. After 3, 6, 12, and 24 months, systolic mean 24‐hour ambulatory blood pressure values were reduced by 10±12, 10±14, 8±15, and 10±15 mm Hg, respectively, when compared with baseline ( P <0.001). Corresponding diastolic values were reduced by 6±8, 6±8, 5±9, and 6±9 mm Hg, respectively ( P <0.001). Periprocedural adverse events occurred in 16 patients, and all recovered without sequelae. CONCLUSIONS: In this single‐center study, uRDN effectively lowered blood pressure up to 24 months after treatment.