Background: Comorbidity-driven microvascular inflammation is posited as a unifying pathophysiologic mechanism for heart failure with preserved ejection fraction (HFpEF). Obesity is proinflammatory and common in HFpEF. We hypothesized that unique obesity-inflammation HFpEF phenotypes exist and are associated with differences in clinical features, fibrosis biomarkers, and functional performance. Methods: Patients (n=301) from 3 HFpEF clinical trials were studied. Unsupervised machine learning (hierarchical clustering) with obese status and 13 inflammatory biomarkers as input variables was performed. Associations of clusters with HFpEF severity and fibrosis biomarkers (PIIINP [procollagen III N-terminal peptide], CITP [C-telopeptide for type I collagen], IGFBP7 [insulin-like growth factor-binding protein-7], and GAL-3 [galectin-3]) were assessed. Results: Hierarchical clustering revealed 3 phenotypes: pan-inflammatory (n=129; 64% obese), noninflammatory (n=83; 55% obese), and obese high CRP (C-reactive protein; n=89; 98% obese). The pan-inflammatory phenotype had more comorbidities and heart failure hospitalizations; higher left atrial volume, NT-proBNP (N-terminal pro-B-type natriuretic peptide), and fibrosis biomarkers; and lower glomerular filtration rate, peak oxygen consumption, 6-minute walk distance, and active hours/day ( P <0.05 for all). The noninflammatory phenotype had the most favorable values for all measures. The obese high CRP phenotype resembled the noninflammatory phenotype except for isolated elevation of CRP and lower functional performance. Hierarchical cluster assignment was independent of CRP genotype combinations that alter CRP levels and more biologically plausible than other clustering approaches. Multiple traditional analytic techniques confirmed and extended the hierarchical clustering findings. Conclusions: Unique obesity-inflammation phenotypes exist in HFpEF and are associated with differences in comorbidity burden, HFpEF severity, and fibrosis. These data support comorbidity-driven microvascular inflammation as a pathophysiologic mechanism for many but not all HFpEF patients.
The transthyretin (TTR) and immunoglobulin light chain proteins do not exist in isolation in cardiac amyloid (CA) plaques. Laser microdissection followed by mass spectrometry-based proteomic (LMD-MS) typing techniques can identify hundreds of co-deposited proteins in the "nano-environment" of amyloid deposits. Some, such as the "amyloid signature" proteins (SAP, APOE, APOA4, vitronectin, clusterin), are specific for amyloid plaques across different tissues and amyloid types. However, many of the remaining proteins are also abundant in the serum or normal tissues making it difficult to discern if they are unique to the amyloid plaque or part of the normal tissue background. We included 288 patients/samples with TTR CA (of which 53 were mutated) diagnosed by endomyocardial biopsy and 5 normal control samples obtained from 3 patients during autopsy. At the time of the meeting updated analyses including 168 cardiac light chain amyloid patients and 15 controls from patients with restrictive and hypertensive cardiomyopathy will be presented. Normalized spectral counts were used as a semi-quantitative measure of abundance. Proteins were considered part of the proteome if their abundance in the amyloid plaque was increased by 1.5-fold compared to normal controls (FDR p<0.05). Of 2240 unique proteins identified across all samples, 42 were differentially expressed in amyloid plaques. These included a) signature proteins: SAP, APOE, APOA4, vitronectin, clusterin; b) serum proteins: albumin, b2-glycoprotein, 7 complement pathway proteins; c) matrix proteins: 2 collagen isoforms, fibulin 1, decorin, PCOLCE2, TIMP3; d) cytosketal and contractile proteins: 2 actin isoforms, MYL2, 8 myosin isoforms, 3 ankyrin isofroms, desmin; and "other" proteins: serpine2, MAGE-like protein-2, pleiotrophin, AMBP, SRPX and QSOX1). The signature and cytoskeletal proteins were the most abundant overall, however, proteins that were most increased compared to normal included (log2 fold change in parentheses): fibulin (24.5), PCOLCE2 (23.5), b2-glycoprotein (23.5), factor H related peptide-2 (24.2), serpine2 (24.7), mage-like protein-2 (22.8), pleiotrophin (23.8), QSOX1 (22.9), SRPX (23.5). B2 glycoprotein was more abundant in wild type TTR samples(p=0.003). APOE (p=0.002), fibulin (p=0.008) and serpine2 (p<0.0001) were more abundant in UK stage (Gilmore JD et al, Eur Heart J 2018) 2/3 patients. Unsupervised hierarchical clustering of patients by normalized protein abundance revealed two major distinct patterns of co-deposited proteins (figure). Patients with high levels of contractility proteins (myosin isoforms, desmin, actins) were characterized by low levels of most other proteins (clusters on the left). Most complement proteins co-deposited along with higher levels of signature proteins (clusters on the right). When comparing clinical and laboratory characteristics between those 2 groups of patients only cardiac strain was found to be significantly higher (worse) in patients with lower levels of contractility proteins (p=0.01). Our data shows that the TTR CA proteome includes signature, serum and cardiac tissue proteins with variable expression according to TTR mutation status and cardiac functional status, which could inform mechanisms of disease pathogenesis. Comparison with diseased controls may further clarify if this proteomic pattern is specific to CA. Figure Disclosures Dasari: The Binding Site: Patents & Royalties: US Patent Rights on Mass Spectroscopy Licensing agreement with The Binding Site, Research Funding. Dispenzieri:Akcea: Consultancy; Intellia: Consultancy; Janssen: Consultancy; Pfizer: Research Funding; Takeda: Research Funding; Celgene: Research Funding; Alnylam: Research Funding.
Global Pulmonary Vascular Remodeling in Pulmonary Hypertension Associated With Heart Failure and Preserved or Reduced Ejection Fraction
Background: We hypothesized that pulmonary venous hypertension in heart failure (HF) leads to predominate remodeling of pulmonary veins and that the severity of venous remodeling is associated with the severity of pulmonary hypertension (PH) in HF. Methods: Patients with HF (n=108; 53 preserved and 55 reduced ejection fraction) with PH (HF-PH; pulmonary artery systolic pressure [PASP] ≥40 mm Hg) were compared to normal controls (n=12) and patients with primary pulmonary veno-occlusive disease (PVOD; n=17). In lung specimens from autopsy (control, HF-PH, and 7 PVOD) or surgery (10 PVOD), quantitative histomorphometry was performed in all analyzable arteries (n=4949), veins (n=7630), and small indeterminate vessels (IV; n=2168) to define percent medial thickness (arteries) and percent intimal thickness (%IT) (arteries, veins, and IV) relative to external diameter. Results: The average arterial percent medial thickness (control, 6.9; HF-PH, 11.0; PVOD, 15.0), arterial %IT (control, 4.9; HF-PH, 14.9; PVOD, 31.1), venous %IT (control, 14.0; HF-PH, 24.9; PVOD, 43.9), and IV %IT (control, 10.6; HF-PH, 25.8; PVOD, 50.0) in HF-PH were higher than controls ( P <0.0001 for all) but lower than PVOD ( P ≤0.005 for all). PASP (mm Hg) was lower in HF-PH (median, 59 [interquartile range, 50–70]) than in PVOD (median, 91 [interquartile range, 82–103]). PASP correlated with arterial percent medial thickness ( r =0.41) and arterial %IT ( r =0.35) but more strongly with venous %IT ( r =0.49) and IV %IT ( r =0.55) ( P <0.0001 for all). Associations between PASP and venous or IV %IT remained significant after adjusting for arterial percent medial thickness and %IT and did not vary by HF type. In patients with right heart catheterization (30 HF-PH, 14 PVOD), similar associations between the transpulmonary gradient and pulmonary vascular remodeling existed, with numerically stronger associations for venous and IV %IT. Although the PASP was slightly higher in patients with HF-PH with right ventricular dysfunction, pulmonary vascular remodeling was not more severe. Pulmonary vascular remodeling severity was associated with reductions in the diffusing capacity of the lungs. Conclusions: In HF, PH is associated with global pulmonary vascular remodeling, but the severity of PH correlates most strongly with venous and small IV intimal thickening, similar to the pattern observed in PVOD. These findings expand our understanding of the pathobiology of PH in HF.
Myocardial Cobalt Levels Are Elevated in the Setting of Total Hip Arthroplasty
Background: Arthroplasty implants commonly contain elemental metal that may undergo wear-related release. Recently, cases of hip implant-associated myocardial injury have been reported. However, we are not aware of any previous study that has systematically measured myocardial metal levels or examined the relationship with total hip arthroplasty (THA). Methods: Archives of our institution were queried for autopsies of individuals who had undergone THA between 1990 and 2013. Myocardial tissue samples were analyzed for cobalt (Co) and chromium (Cr) levels with inductively coupled plasma mass spectroscopy. Seventy-five Co/Cr-on-polyethylene THA cases were included (mean age at time of death = 77.4 years; 49% women) as were 73 non-arthroplasty controls matched for age, sex, and history of hypertension and diabetes mellitus. Results: Significantly higher median myocardial concentrations of Co were observed in individuals with THA compared with controls (0.12 versus 0.06 μg/g, p < 0.0001). The median Co concentration was 69% higher in patients who had undergone THA revision (0.169 μg/g) than in those who underwent primary THA (0.100 μg/g; p = 0.004). In general, higher Co levels were observed in those with multiple replaced joints, although this finding only trended toward significance. Cardiomegaly, interstitial fibrosis, and decreased ejection fraction were observed more frequently in the postmortem samples of patients with implants than in those of controls (p = 0.0002, 0.044, and 0.0039, respectively). Conclusions: We believe this to be the first study to quantify metal levels in cardiac tissue in patients with and without joint replacement. The elevated Co levels, in concert with cardiomegaly and increased interstitial fibrosis found during autopsy, in the arthroplasty cohort are novel, important findings. Although Co levels were significantly elevated above those in controls, the majority were below those seen in clinical case reports of death from Co cardiotoxicity associated with metal-on-metal prostheses. Level of Evidence: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.
FOXO3a regulates BNIP3 and modulates mitochondrial calcium, dynamics, and function in cardiac stress
The forkhead box O3a (FOXO3a) transcription factor has been shown to regulate glucose metabolism, muscle atrophy, and cell death in postmitotic cells. Its role in regulation of mitochondrial and myocardial function is not well studied. Based on previous work, we hypothesized that FOXO3a, through BCL2/adenovirus E1B 19-kDa protein-interacting protein 3 (BNIP3), modulates mitochondrial morphology and function in heart failure (HF). We modulated the FOXO3a-BNIP3 pathway in normal and phenylephrine (PE)-stressed adult cardiomyocytes (ACM) in vitro and developed a cardiotropic adeno-associated virus serotype 9 encoding dominant-negative FOXO3a (AAV9.dn-FX3a) for gene delivery in a rat model of HF with preserved ejection fraction (HFpEF). We found that FOXO3a upregulates BNIP3 expression in normal and PE-stressed ACM, with subsequent increases in mitochondrial Ca2+, leading to decreased mitochondrial membrane potential, mitochondrial fragmentation, and apoptosis. Whereas dn-FX3a attenuated the increase in BNIP3 expression and its consequences in PE-stressed ACM, AAV9.dn-FX3a delivery in an experimental model of HFpEF decreased BNIP3 expression, reversed adverse left ventricular remodeling, and improved left ventricular systolic and, particularly, diastolic function, with improvements in mitochondrial structure and function. Moreover, AAV9.dn-FX3a restored phospholamban phosphorylation at S16 and enhanced dynamin-related protein 1 phosphorylation at S637. Furthermore, FOXO3a upregulates maladaptive genes involved in mitochondrial apoptosis, autophagy, and cardiac atrophy. We conclude that FOXO3a activation in cardiac stress is maladaptive, in that it modulates Ca2+ cycling, Ca2+ homeostasis, and mitochondrial dynamics and function. Our results suggest an important role of FOXO3a in HF, making it an attractive potential therapeutic target. Listen to this article's corresponding podcast at http://ajpheart.podbean.com/e/role-of-foxo3a-in-heart-failure/ .
Correlation of histomorphological pattern of cardiac amyloid deposition with amyloid type: a histological and proteomic analysis of 108 cases
Aims Prognostication and treatment selection for cardiac amyloidosis requires accurate amyloid typing. The aim of this study was to investigate the utility of histomorphology for predicting type. Methods and results Autopsy cases with cardiac amyloidosis (1998–2010) were typed by the use of mass spectrometry‐based proteomics. Deposition patterns were correlated with amyloid type. Among 108 decedents (mean age 75 years; 69% men), 107 had a single type, including transthyretin (ATTR) (60 cases), amyloid light chain (AL) (32 λ; 12 κ), amyloid A (AA) (two), and apolipoprotein AIV (AApoAIV) (one). Interstitial deposition was more extensive in AL amyloidosis cases than in ATTR cases [odds ratio (OR) 6.8, P = 0.0004]. Histomorphological patterns of interstitial deposition were mixed in 61% of AL amyloidosis cases and in 61% of ATTR cases, but diffuse pericellular deposits favoured AL amyloidosis (OR 10.7, P = 0.0001), nodular deposits favoured ATTR (OR 3.1, P = 0.0229), and discrete pericellular deposits tended to partially favour ATTR (OR 1.7, P = 0.1970). Arterial and venous deposits each favoured AL amyloidosis (OR ranging from 9.3 to 192.0, P‐value ranging from 0.0022 to <0.0001), and were severe in AL amyloidosis. Endocardial deposits favoured AL amyloidosis (OR 46.3, P < 0.0001) and were also more severe in AL amyloidosis. Conclusions The extent and distribution of cardiac amyloidosis strongly correlate with amyloid type, suggesting fundamental differences in the pathobiology of deposition. The tendency for mixed patterns to occur limits the practicality and accuracy of using histopathology for amyloid typing.