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1.
Stroke ; 55(6): 1676-1679, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38572634

RESUMO

BACKGROUND: The effects of lipid-lowering drug targets on different ischemic stroke subtypes are not fully understood. We aimed to explore the mechanisms by which lipid-lowering drug targets differentially affect the risk of ischemic stroke subtypes and their underlying pathophysiology. METHODS: Using a 2-sample Mendelian randomization approach, we assessed the effects of genetically proxied low-density lipoprotein cholesterol (LDL-c) and 3 clinically approved LDL-lowering drugs (HMGCR [3-hydroxy-3-methylglutaryl-CoA reductase], PCSK9 [proprotein convertase subtilisin/kexin type 9], and NPC1L1 [Niemann-Pick C1-Like 1]) on stroke subtypes and brain imaging biomarkers associated with small vessel stroke (SVS), including white matter hyperintensity volume and perivascular spaces. RESULTS: In genome-wide Mendelian randomization analyses, lower genetically predicted LDL-c was significantly associated with a reduced risk of any stroke, ischemic stroke, and large artery stroke, supporting previous findings. Significant associations between genetically predicted LDL-c and cardioembolic stroke, SVS, and biomarkers, perivascular space and white matter hyperintensity volume, were not identified in this study. In drug-target Mendelian randomization analysis, genetically proxied reduced LDL-c through NPC1L1 inhibition was associated with lower odds of perivascular space (odds ratio per 1-mg/dL decrease, 0.79 [95% CI, 0.67-0.93]) and with lower odds of SVS (odds ratio, 0.29 [95% CI, 0.10-0.85]). CONCLUSIONS: This study provides supporting evidence of a potentially protective effect of LDL-c lowering through NPC1L1 inhibition on perivascular space and SVS risk, highlighting novel therapeutic targets for SVS.


Assuntos
Doenças de Pequenos Vasos Cerebrais , LDL-Colesterol , AVC Isquêmico , Análise da Randomização Mendeliana , Pró-Proteína Convertase 9 , Humanos , AVC Isquêmico/genética , AVC Isquêmico/diagnóstico por imagem , LDL-Colesterol/sangue , Doenças de Pequenos Vasos Cerebrais/genética , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Pró-Proteína Convertase 9/genética , Biomarcadores/sangue , Proteínas de Membrana Transportadoras/genética , Hidroximetilglutaril-CoA Redutases/genética , Encéfalo/diagnóstico por imagem , Proteínas de Membrana/genética , Estudo de Associação Genômica Ampla , Feminino
2.
Circ Res ; 131(6): 545-554, 2022 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-35946401

RESUMO

BACKGROUND: Microvascular damage from large artery stiffness (LAS) in pancreatic, hepatic, and skeletal muscles may affect glucose homeostasis. Our goal was to evaluate the association between LAS and the risk of type 2 diabetes using prospectively collected, carefully phenotyped measurements of LAS as well as Mendelian randomization analyses. METHODS: Carotid-femoral pulse wave velocity (CF-PWV) and brachial and central pulse pressure were measured in 5676 participants of the FHS (Framingham Heart Study) without diabetes. We used Cox proportional hazards regression to evaluate the association of CF-PWV and pulse pressure with incident diabetes. We subsequently performed 2-sample Mendelian randomization analyses evaluating the associations of genetically predicted brachial pulse pressure with type 2 diabetes in the UKBB (United Kingdom Biobank). RESULTS: In FHS, individuals with higher CF-PWV were older, more often male, and had higher body mass index and mean arterial pressure compared to those with lower CF-PWV. After a median follow-up of 7 years, CF-PWV and central pulse pressure were associated with an increased risk of new-onset diabetes (per SD increase, multivariable-adjusted CF-PWV hazard ratio, 1.36 [95% CI, 1.03-1.76]; P=0.030; central pulse pressure multivariable-adjusted CF-PWV hazard ratio, 1.26 [95% CI, 1.08-1.48]; P=0.004). In United Kingdom Biobank, genetically predicted brachial pulse pressure was associated with type 2 diabetes, independent of mean arterial pressure (adjusted odds ratio, 1.16 [95% CI, 1.00-1.35]; P=0.049). CONCLUSIONS: Using prospective cohort data coupled with Mendelian randomization analyses, we found evidence supporting that greater LAS is associated with increased risk of developing diabetes. LAS may play an important role in glucose homeostasis and may serve as a useful marker of future diabetes risk.


Assuntos
Diabetes Mellitus Tipo 2 , Rigidez Vascular , Bancos de Espécimes Biológicos , Artéria Braquial , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Glucose , Humanos , Estudos Longitudinais , Masculino , Estudos Prospectivos , Análise de Onda de Pulso , Rigidez Vascular/genética
3.
Arterioscler Thromb Vasc Biol ; 43(2): 359-366, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36601961

RESUMO

BACKGROUND: Observational studies identified elevated blood pressure (BP) as a strong risk factor for thoracic aortic dilation, and BP reduction is the primary medical intervention recommended to prevent progression of aortic aneurysms. However, although BP may impact aortic dilation, aortic size may also impact BP. The causal relationship between BP and thoracic aortic size has not been reliably established. METHODS: Genome-wide association studies summary statistics were obtained for BP and ascending thoracic aortic diameter (AscAoD). Causal effects of BP on AscAoD were estimated using 2-sample Mendelian randomization using a range of pleiotropy-robust methods. RESULTS: Genetically predicted increased systolic BP, diastolic BP, and mean arterial pressure all significantly associate with higher AscAoD (systolic BP: ß estimate, 0.0041 mm/mm Hg [95% CI, 0.0008-0.0074]; P=0.02, diastolic BP: ß estimate, 0.0272 mm/mm Hg [95% CI, 0.0224-0.0320]; P<0.001, and mean arterial pressure: ß estimate, 0.0168 mm/mm Hg [95% CI, 0.0130-0.0206]; P<0.001). Genetically predicted pulse pressure, meanwhile, had an inverse association with AscAoD (ß estimate, -0.0155 mm/mm Hg [95% CI, -0.0213 to -0.0096]; P<0.001). Multivariable Mendelian randomization analyses showed that genetically predicted increased mean arterial pressure and reduced pulse pressure were independently associated with AscAoD. Bidirectional Mendelian randomization demonstrated that genetically predicted AscAoD was inversely associated with pulse pressure (ß estimate, -2.0721 mm Hg/mm [95% CI, -3.1137 to -1.0306]; P<0.001) and systolic BP (ß estimate, -1.2878 mm Hg/mm [95% CI, -2.3533 to -0.2224]; P=0.02), while directly associated with diastolic BP (0.8203 mm Hg/mm [95% CI, 0.2735-1.3672]; P=0.004). CONCLUSIONS: BP likely contributes causally to ascending thoracic aortic dilation. Increased AscAoD likely contributes to lower systolic BP and pulse pressure, but not diastolic BP, consistent with the hemodynamic consequences of a reduced aortic diameter.


Assuntos
Hipertensão , Análise da Randomização Mendeliana , Humanos , Pressão Sanguínea , Estudo de Associação Genômica Ampla , Hipertensão/epidemiologia , Hipertensão/genética , Hemodinâmica
4.
Am J Physiol Heart Circ Physiol ; 325(4): H617-H628, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37477688

RESUMO

Aging increases arterial stiffness and wave reflections that augment left ventricular wasted pressure effort (WPE). A single bout of exercise may be effective at acutely reducing WPE via reductions in arterial wave reflections. In young adults (YA) acute aerobic exercise decreases, whereas handgrip increases, wave reflections. Whether acute exercise mitigates or exacerbates WPE and arterial wave reflection in healthy aging warrants further examination. The purpose of this study was to determine if there are age-related differences in WPE and wave reflection during acute handgrip and aerobic exercise. When compared with baseline, WPE increased substantially in older adults (OA) during handgrip (5,219 ± 2,396 vs. 7,019 ± 2,888 mmHg·ms, P < 0.001). When compared with baseline, there was a robust reduction in WPE in OA during moderate-intensity aerobic exercise (5,428 ± 2,084 vs. 3,290 ± 1,537 mmHg·ms, P < 0.001), despite absolute WPE remaining higher in OA compared with YA during moderate-intensity aerobic exercise (OA 3,290 ± 1,537 vs. YA 1,188 ± 962 mmHg·ms, P < 0.001). There was no change in wave reflection timing indexed to ejection duration in OA during handgrip (40 ± 6 vs. 38 ± 4%, P = 0.41) or moderate-intensity aerobic exercise (40 ± 5 vs. 42 ± 8%, P = 0.99). Conversely, there was an earlier return of wave reflection in YA during handgrip (60 ± 11 vs. 52 ± 6%, P < 0.001) and moderate-intensity aerobic exercise (59 ± 7 vs. 51 ± 9%, P < 0.001). Changes in stroke volume were not different between groups during handgrip (P = 0.08) or aerobic exercise (P = 0.47). The greater increase in WPE during handgrip and decrease in WPE during aerobic exercise suggest that aortic hemodynamic responses to acute exercise are exaggerated with healthy aging without affecting stroke volume.NEW & NOTEWORTHY We demonstrated that acute aerobic exercise attenuated, whereas handgrip augmented, left ventricular hemodynamic load from wave reflections more in healthy older (OA) compared with young adults (YA) without altering stroke volume. These findings suggest an exaggerated aortic hemodynamic response to acute exercise perturbations with aging. They also highlight the importance of considering exercise modality when examining aortic hemodynamic responses to acute exercise in older adults.


Assuntos
Envelhecimento Saudável , Rigidez Vascular , Adulto Jovem , Humanos , Idoso , Força da Mão , Artérias , Exercício Físico/fisiologia , Hemodinâmica , Pressão Sanguínea/fisiologia , Rigidez Vascular/fisiologia
5.
Circulation ; 141(12): 1001-1026, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32202936

RESUMO

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.


Assuntos
Insuficiência Cardíaca/epidemiologia , Pesquisa/normas , Humanos , National Heart, Lung, and Blood Institute (U.S.) , Volume Sistólico , Estados Unidos
6.
Circulation ; 141(18): 1463-1476, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32237898

RESUMO

BACKGROUND: Apo (apolipoprotein) M mediates the physical interaction between high-density lipoprotein (HDL) particles and sphingosine-1-phosphate (S1P). Apo M exerts anti-inflammatory and cardioprotective effects in animal models. METHODS: In a subset of PHFS (Penn Heart Failure Study) participants (n=297), we measured apo M by Enzyme-Linked ImmunoSorbent Assay (ELISA). We also measured total S1P by liquid chromatography-mass spectrometry and isolated HDL particles to test the association between apo M and HDL-associated S1P. We confirmed the relationship between apo M and outcomes using modified aptamer-based apo M measurements among 2170 adults in the PHFS and 2 independent cohorts: the Washington University Heart Failure Registry (n=173) and a subset of TOPCAT (Treatment of Preserved Cardiac Function Heart Failure With an Aldosterone Antagonist Trial; n=218). Last, we examined the relationship between apo M and ≈5000 other proteins (SomaScan assay) to identify biological pathways associated with apo M in heart failure. RESULTS: In the PHFS, apo M was inversely associated with the risk of death (standardized hazard ratio, 0.56 [95% CI, 0.51-0.61]; P<0.0001) and the composite of death/ventricular assist device implantation/heart transplantation (standardized hazard ratio, 0.62 [95% CI, 0.58-0.67]; P<0.0001). This relationship was independent of HDL cholesterol or apo AI levels. Apo M remained associated with death (hazard ratio, 0.78 [95% CI, 0.69-0.88]; P<0.0001) and the composite of death/ventricular assist device/heart transplantation (hazard ratio, 0.85 [95% CI, 0.76-0.94]; P=0.001) in models that adjusted for multiple confounders. This association was present in both heart failure with reduced and preserved ejection fraction and was replicated in the Washington University cohort and a cohort with heart failure with preserved ejection fraction only (TOPCAT). The S1P and apo M content of isolated HDL particles strongly correlated (R=0.81, P<0.0001). The top canonical pathways associated with apo M were inflammation (negative association), the coagulation system (negative association), and liver X receptor/retinoid X receptor activation (positive association). The relationship with inflammation was validated with multiple inflammatory markers measured with independent assays. CONCLUSIONS: Reduced circulating apo M is independently associated with adverse outcomes across the spectrum of human heart failure. Further research is needed to assess whether the apo M/S1P axis is a suitable therapeutic target in heart failure.


Assuntos
Apolipoproteínas M/sangue , Insuficiência Cardíaca/sangue , Proteoma , Idoso , Biomarcadores/sangue , Regulação para Baixo , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/terapia , Humanos , Lipoproteínas HDL/sangue , Lisofosfolipídeos/sangue , Masculino , Pessoa de Meia-Idade , Prognóstico , Proteômica , Ensaios Clínicos Controlados Aleatórios como Assunto , Sistema de Registros , Medição de Risco , Fatores de Risco , Esfingosina/análogos & derivados , Esfingosina/sangue , Fatores de Tempo , Estados Unidos
7.
Am J Physiol Heart Circ Physiol ; 320(5): H1802-H1812, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33710924

RESUMO

Central aortic pressure waveforms contain valuable prognostic information in addition to central systolic pressure. Using pressure-flow relations, wave separation analysis can be used to decompose aortic pressure waveforms into forward- (Pf) and backward-traveling (Pb) components. Reflection magnitude, the ratio of pressure amplitudes (RM = Pb/Pf), is a predictor of heart failure and all-cause mortality. Aortic flow can be measured via Doppler echocardiography or estimated using a triangular flow waveform; however, the latter may underestimate the flow waveform convexity and overestimate Pb and RM. We sought to determine the accuracy of a personalized synthetic physiologic flow waveform, compared with triangular and measured flow waveforms, for estimating wave reflection indices in 49 healthy young (27 ± 6 yr) and 29 older adults [66 ± 6 yr; 20 healthy, 9 chronic kidney disease (CKD)]. Aortic pressure and measured flow waveforms were acquired via radial tonometry and echocardiography, respectively. Triangular and physiologic flow waveforms were constructed from aortic pressure waveforms. Compared with the measured flow waveform, the triangular waveform underestimated Pf in older, but not young, adults and overestimated Pb and RM in both groups. The physiologic waveform was equivalent to measured flow in deriving all wave reflection indices and yielded smaller mean absolute biases than the triangular waveform in all instances (P < 0.05). Lastly, central pulse pressure was associated with triangular, but not physiologic, mean biases for Pb and RM independent of age or central arterial stiffness (P < 0.05). These findings support the use of personalized physiologic flow waveforms as a more robust alternative to triangular flow waveforms when true flow cannot be measured.NEW & NOTEWORTHY We demonstrate that triangular flow waveforms overestimate wave reflection indices, particularly at higher central pulse pressures independent of age or carotid-femoral pulse wave velocity. In contrast, personalized physiologic flow waveforms provide equivalent wave reflection estimates as measured flow waveforms, thereby offering a more robust alternative to triangulation when aortic flow cannot be measured.


Assuntos
Aorta/fisiologia , Pressão Arterial , Determinação da Pressão Arterial , Adulto , Fatores Etários , Idoso , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/fisiopatologia , Velocidade da Onda de Pulso Carótido-Femoral , Estudos de Casos e Controles , Ecocardiografia Doppler de Pulso , Feminino , Humanos , Masculino , Manometria , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Insuficiência Renal Crônica/diagnóstico , Insuficiência Renal Crônica/fisiopatologia , Reprodutibilidade dos Testes , Fatores de Tempo , Rigidez Vascular , Adulto Jovem
8.
Exp Physiol ; 106(8): 1720-1730, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33999464

RESUMO

NEW FINDINGS: What is the central question of this study? There is a paradoxical reduction in augmentation index during lower-body dynamic (LBD) exercise in the face of an increase in central pressure. To determine causality, the amplitudes of forward and backward pressure waves were assessed separately using wave separation analysis. What is the main finding and its importance? Reflection magnitude decreased during LBD exercise in healthy young adults and was attributable to an increased forward pressure wave amplitude and decreased backward pressure wave amplitude. This vasoactive response might limit the adverse effects of wave reflection during LBD exercise, optimizing ventricular-arterial interactions. ABSTRACT: Acute lower-body dynamic (LBD) exercise decreases surrogate measures of wave reflection, such as the augmentation index. However, the augmentation index is influenced by the combined effects of wave reflection timing, magnitude and other confounding factors external to wave reflection, which make it difficult to discern the origin of changes in surrogate measures. The relative contributions of forward (Pf) and backward (Pb) pressure wave amplitudes to central pressure can be determined by wave separation analysis. Reflection magnitude (RM = Pb/Pf) and the timing of apparent wave reflection return can also be determined. We tested the hypothesis that acute LBD exercise decreases RM and reflected wave transit time (RWTT). Applanation tonometry was used to record radial artery pressure waveforms in 25 adults (24 ± 4 years of age) at baseline and during light-, moderate- and vigorous-intensity exercise. Wave separation analysis was conducted offline using a personalized physiological flow wave to determine Pf, Pb, RM and RWTT. The RM decreased during all intensities of exercise compared with baseline (all P < 0.001; baseline, 43 ± 5%; light, 33 ± 6%; moderate, 23 ± 7%; vigorous, 17 ± 5%). The reduction in RM was attributable to the combined effect of increased Pf and decreased Pb during exercise. The RWTT decreased during all intensities of exercise compared with baseline (all P < 0.04; baseline, 156 ± 17 ms; light, 144 ± 15 ms; moderate, 129 ± 16 ms; vigorous, 121 ± 17 ms). Lastly, in a stepwise multilinear regression, Pf, but not Pb and RWTT, contributed to increased central pulse pressure during LBD exercise. These data show that wave reflection decreased and that central pulse pressure is most influenced by Pf during LBD exercise.


Assuntos
Artérias , Exercício Físico , Pressão Sanguínea/fisiologia , Frequência Cardíaca , Ventrículos do Coração , Humanos , Adulto Jovem
9.
Nitric Oxide ; 106: 17-23, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33080411

RESUMO

BACKGROUND: Chronic Kidney Disease (CKD) patients exhibit a reduced exercise capacity that impacts quality of life. Dietary nitrate supplementation has been shown to have favorable effects on exercise capacity in disease populations by reducing the oxygen cost of exercise. This study investigated whether dietary nitrates would acutely improve exercise capacity in CKD patients. METHODS AND RESULTS: In this randomized, double-blinded crossover study, 12 Stage 3-4 CKD patients (Mean ± SEM: Age, 60 ± 5yrs; eGFR, 50.3 ± 4.6 ml/min/1.73 m2) received an acute dose of 12.6 mmol of dietary nitrate in the form of concentrated beetroot juice (BRJ) and a nitrate depleted placebo (PLA). Skeletal muscle mitochondrial oxidative function was assessed using near-infrared spectroscopy. Cardiopulmonary exercise testing was performed on a cycle ergometer, with intensity increased by 25 W every 3 min until volitional fatigue. Plasma nitric oxide (NO) metabolites (NOm; nitrate, nitrite, low molecular weight S-nitrosothiols, and metal bound NO) were determined by gas-phase chemiluminescence. Plasma NOm values were significantly increased following BRJ (BRJ vs. PLA: 1074.4 ± 120.4 µM vs. 28.4 ± 6.6 µM, p < 0.001). Total work performed (44.4 ± 10.6 vs 39.6 ± 9.9 kJ, p = 0.03) and total exercise time (674 ± 85 vs 627 ± 86s, p = 0.04) were significantly greater following BRJ. Oxygen consumption at the ventilatory threshold was also improved by BRJ (0.90 ± 0.08 vs. 0.74 ± 0.06 L/min, p = 0.04). These changes occurred in the absence of improved skeletal muscle mitochondrial oxidative capacity (p = 0.52) and VO2peak (p = 0.35). CONCLUSIONS: Our findings demonstrate that inorganic nitrate can acutely improve exercise capacity in CKD patients. The effects of chronic nitrate supplementation on CKD related exercise intolerance should be investigated in future studies.


Assuntos
Tolerância ao Exercício/efeitos dos fármacos , Nitratos/uso terapêutico , Insuficiência Renal Crônica/dietoterapia , Adulto , Idoso , Beta vulgaris/química , Estudos Cross-Over , Suplementos Nutricionais , Método Duplo-Cego , Teste de Esforço/efeitos dos fármacos , Feminino , Sucos de Frutas e Vegetais , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/efeitos dos fármacos , Projetos Piloto
10.
Arterioscler Thromb Vasc Biol ; 40(5): 1034-1043, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31875700

RESUMO

Despite the wide recognition of larger artery stiffness as a highly clinically relevant and independent prognostic biomarker, it has yet be incorporated into routine clinical practice and to take a more prominent position in clinical guidelines. An important reason may be the plethora of methods and devices claiming to measure arterial stiffness in humans. This brief review provides a concise overview of methods in use, indicating strengths and weaknesses. We classified and graded methods, highly weighing their scrutiny and purity in quantifying arterial stiffness, rather than focusing on their ease of application or the level at which methods have demonstrated their prognostic and diagnostic potential.


Assuntos
Artérias/diagnóstico por imagem , Determinação da Pressão Arterial , Doenças Cardiovasculares/diagnóstico , Técnicas de Imagem por Elasticidade , Análise de Onda de Pulso , Rigidez Vascular , Pressão Arterial , Artérias/fisiopatologia , Doenças Cardiovasculares/fisiopatologia , Elasticidade , Humanos , Valor Preditivo dos Testes , Prognóstico , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença
11.
J Cardiovasc Magn Reson ; 23(1): 55, 2021 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-34011382

RESUMO

BACKGROUND: Cardiovascular magnetic resonance (CMR) myocardial strain analysis using feature tracking (FT) is an increasingly popular method to assess cardiac function. However, different software packages produce different strain values from the same images and there is little guidance regarding which software package would be the best to use. We explored a framework under which different software packages could be compared and used based on their abilities to differentiate disease from health and differentiate disease severity based on outcome. METHOD: To illustrate this concept, we compared 4-chamber left ventricular (LV) peak longitudinal strain (GLS) analyzed from retrospective electrocardiogram gated cine imaging performed on 1.5 T CMR scanners using three CMR post-processing software packages in their abilities to discriminate a group of 45 patients with heart failure with preserved ejection fraction (HFpEF) from 26 controls without cardiovascular disease and to discriminate disease severity based on outcomes. The three different post-processing software used were SuiteHeart, cvi42, and DRA-Trufistrain. RESULTS: All three software packages were able to distinguish HFpEF patients from controls. 4-chamber peak GLS by SuiteHeart was shown to be a better discriminator of adverse outcomes in HFpEF patients than 4-chamber GLS derived from cvi42 or DRA-Trufistrain. CONCLUSION: We illustrated a framework to compare feature tracking GLS derived from different post-processing software packages. Publicly available imaging data sets with outcomes would be important to validate the growing number of CMR-FT software packages.


Assuntos
Insuficiência Cardíaca , Insuficiência Cardíaca/diagnóstico por imagem , Humanos , Imagem Cinética por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Valor Preditivo dos Testes , Estudos Retrospectivos , Software , Volume Sistólico , Função Ventricular Esquerda
12.
Circulation ; 139(11): 1435-1450, 2019 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-30856000

RESUMO

Heart failure with preserved ejection fraction (HFpEF) is a complex syndrome with an increasingly recognized heterogeneity in pathophysiology. Exercise intolerance is the hallmark of HFpEF and appears to be caused by both cardiac and peripheral abnormalities in the arterial tree and skeletal muscle. Mitochondrial abnormalities can significantly contribute to impaired oxygen utilization and the resulting exercise intolerance in HFpEF. We review key aspects of the complex biology of this organelle, the clinical relevance of mitochondrial function, the methods that are currently available to assess mitochondrial function in humans, and the evidence supporting a role for mitochondrial dysfunction in the pathophysiology of HFpEF. We also discuss the role of mitochondrial function as a therapeutic target, some key considerations for the design of early-phase clinical trials using agents that specifically target mitochondrial function to improve symptoms in patients with HFpEF, and ongoing trials with mitochondrial agents in HFpEF.


Assuntos
Metabolismo Energético , Tolerância ao Exercício , Insuficiência Cardíaca/metabolismo , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Musculares/metabolismo , Músculo Esquelético/metabolismo , Miócitos Cardíacos/metabolismo , Volume Sistólico , Função Ventricular Esquerda , Trifosfato de Adenosina/metabolismo , Animais , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Mitocôndrias Cardíacas/patologia , Mitocôndrias Musculares/patologia , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Miócitos Cardíacos/patologia , Consumo de Oxigênio
13.
Am J Hematol ; 95(12): 1578-1589, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32857878

RESUMO

Thrombotic complications are frequent in COVID-19 and contribute significantly to mortality and morbidity. We review several mechanisms of hypercoagulability in sepsis that may be upregulated in COVID-19. These include immune-mediated thrombotic mechanisms, complement activation, macrophage activation syndrome, antiphospholipid antibody syndrome, hyperferritinemia, and renin-angiotensin system dysregulation. We highlight biomarkers within each pathway with potential prognostic value in COVID-19. Lastly, recent observational studies have evaluated a role for the expanded use of therapeutic anticoagulation in COVID-19. We review strengths and weaknesses of these studies, and we also discuss the hypothetical benefit and anticipated challenges of fibrinolytic therapy in COVID-19.


Assuntos
COVID-19/complicações , SARS-CoV-2 , Trombose/epidemiologia , Anticoagulantes/uso terapêutico , Síndrome Antifosfolipídica , COVID-19/imunologia , COVID-19/terapia , Ativação do Complemento , Estado Terminal/epidemiologia , Síndrome da Liberação de Citocina/epidemiologia , Coagulação Intravascular Disseminada , Ferritinas/sangue , Humanos , Hiperferritinemia/epidemiologia , Ativação de Macrófagos , Embolia Pulmonar/epidemiologia , Sistema Renina-Angiotensina/fisiologia , Trombofilia/sangue , Trombofilia/epidemiologia , Trombofilia/imunologia , Trombose/sangue , Trombose/imunologia , Tratamento Farmacológico da COVID-19
14.
Circ Res ; 120(7): 1151-1161, 2017 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-27927683

RESUMO

RATIONALE: Nitrate-rich beetroot juice has been shown to improve exercise capacity in heart failure with preserved ejection fraction, but studies using pharmacological preparations of inorganic nitrate are lacking. OBJECTIVES: To determine (1) the dose-response effect of potassium nitrate (KNO3) on exercise capacity; (2) the population-specific pharmacokinetic and safety profile of KNO3 in heart failure with preserved ejection fraction. METHODS AND RESULTS: We randomized 12 subjects with heart failure with preserved ejection fraction to oral KNO3 (n=9) or potassium chloride (n=3). Subjects received 6 mmol twice daily during week 1, followed by 6 mmol thrice daily during week 2. Supine cycle ergometry was performed at baseline (visit 1) and after each week (visits 2 and 3). Quality of life was assessed with the Kansas City Cardiomyopathy Questionnaire. The primary efficacy outcome, peak O2-uptake, did not significantly improve (P=0.13). Exploratory outcomes included exercise duration and quality of life. Exercise duration increased significantly with KNO3 (visit 1: 9.87, 95% confidence interval [CI] 9.31-10.43 minutes; visit 2: 10.73, 95% CI 10.13-11.33 minute; visit 3: 11.61, 95% CI 11.05-12.17 minutes; P=0.002). Improvements in the Kansas City Cardiomyopathy Questionnaire total symptom (visit 1: 58.0, 95% CI 52.5-63.5; visit 2: 66.8, 95% CI 61.3-72.3; visit 3: 70.8, 95% CI 65.3-76.3; P=0.016) and functional status scores (visit 1: 62.2, 95% CI 58.5-66.0; visit 2: 68.6, 95% CI 64.9-72.3; visit 3: 71.1, 95% CI 67.3-74.8; P=0.01) were seen after KNO3. Pronounced elevations in trough levels of nitric oxide metabolites occurred with KNO3 (visit 2: 199.5, 95% CI 98.7-300.2 µmol/L; visit 3: 471.8, 95% CI 377.8-565.8 µmol/L) versus baseline (visit 1: 38.0, 95% CI 0.00-132.0 µmol/L; P<0.001). KNO3 did not lead to clinically significant hypotension or methemoglobinemia. After 6 mmol of KNO3, systolic blood pressure was reduced by a maximum of 17.9 (95% CI -28.3 to -7.6) mm Hg 3.75 hours later. Peak nitric oxide metabolites concentrations were 259.3 (95% CI 176.2-342.4) µmol/L 3.5 hours after ingestion, and the median half-life was 73.0 (interquartile range 33.4-232.0) minutes. CONCLUSIONS: KNO3 is potentially well tolerated and improves exercise duration and quality of life in heart failure with preserved ejection fraction. This study reinforces the efficacy of KNO3 and suggests that larger randomized trials are warranted. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT02256345.


Assuntos
Insuficiência Cardíaca/tratamento farmacológico , Nitratos/farmacocinética , Compostos de Potássio/farmacocinética , Volume Sistólico , Idoso , Exercício Físico , Feminino , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/reabilitação , Humanos , Masculino , Pessoa de Meia-Idade , Nitratos/efeitos adversos , Compostos de Potássio/efeitos adversos , Qualidade de Vida
15.
Eur Heart J ; 39(43): 3847-3854, 2018 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-29947746

RESUMO

Due to the cyclic function of the human heart, pressure and flow in the circulation are pulsatile rather than continuous. Addressing pulsatile haemodynamics starts with the most convenient measurement, brachial pulse pressure, which is widely available, related to development and treatment of heart failure (HF), but often confounded in patients with established HF. The next level of analysis consists of central (rather than brachial) pressures and, more importantly, of wave reflections. The latter are closely related to left ventricular late systolic afterload, ventricular remodelling, diastolic dysfunction, exercise capacity, and, in the long-term, the risk of new-onset HF. Wave reflection may also represent a suitable therapeutic target. Treatments for HF with preserved and reduced ejection fraction, based on a reduction of wave reflection, are emerging. A full understanding of ventricular-arterial coupling, however, requires dedicated analysis of time-resolved pressure and flow signals, which can be readily accomplished with contemporary non-invasive imaging and modelling techniques. This review provides a summary of our current understanding of pulsatile haemodynamics in HF.


Assuntos
Pressão Sanguínea/fisiologia , Insuficiência Cardíaca/fisiopatologia , Fluxo Pulsátil/fisiologia , Idoso , Feminino , Hemodinâmica , Humanos , Masculino , Modelos Cardiovasculares
16.
JAMA ; 322(22): 2191-2202, 2019 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-31821430

RESUMO

Importance: Hereditary transthyretin (TTR) amyloid cardiomyopathy (hATTR-CM) due to the TTR V122I variant is an autosomal-dominant disorder that causes heart failure in elderly individuals of African ancestry. The clinical associations of carrying the variant, its effect in other African ancestry populations including Hispanic/Latino individuals, and the rates of achieving a clinical diagnosis in carriers are unknown. Objective: To assess the association between the TTR V122I variant and heart failure and identify rates of hATTR-CM diagnosis among carriers with heart failure. Design, Setting, and Participants: Cross-sectional analysis of carriers and noncarriers of TTR V122I of African ancestry aged 50 years or older enrolled in the Penn Medicine Biobank between 2008 and 2017 using electronic health record data from 1996 to 2017. Case-control study in participants of African and Hispanic/Latino ancestry with and without heart failure in the Mount Sinai BioMe Biobank enrolled between 2007 and 2015 using electronic health record data from 2007 to 2018. Exposures: TTR V122I carrier status. Main Outcomes and Measures: The primary outcome was prevalent heart failure. The rate of diagnosis with hATTR-CM among TTR V122I carriers with heart failure was measured. Results: The cross-sectional cohort included 3724 individuals of African ancestry with a median age of 64 years (interquartile range, 57-71); 1755 (47%) were male, 2896 (78%) had a diagnosis of hypertension, and 753 (20%) had a history of myocardial infarction or coronary revascularization. There were 116 TTR V122I carriers (3.1%); 1121 participants (30%) had heart failure. The case-control study consisted of 2307 individuals of African ancestry and 3663 Hispanic/Latino individuals; the median age was 73 years (interquartile range, 68-80), 2271 (38%) were male, 4709 (79%) had a diagnosis of hypertension, and 1008 (17%) had a history of myocardial infarction or coronary revascularization. There were 1376 cases of heart failure. TTR V122I was associated with higher rates of heart failure (cross-sectional cohort: n = 51/116 TTR V122I carriers [44%], n = 1070/3608 noncarriers [30%], adjusted odds ratio, 1.7 [95% CI, 1.2-2.4], P = .006; case-control study: n = 36/1376 heart failure cases [2.6%], n = 82/4594 controls [1.8%], adjusted odds ratio, 1.8 [95% CI, 1.2-2.7], P = .008). Ten of 92 TTR V122I carriers with heart failure (11%) were diagnosed as having hATTR-CM; the median time from onset of symptoms to clinical diagnosis was 3 years. Conclusions and Relevance: Among individuals of African or Hispanic/Latino ancestry enrolled in 2 academic medical center-based biobanks, the TTR V122I genetic variant was significantly associated with heart failure.


Assuntos
Neuropatias Amiloides Familiares/genética , Negro ou Afro-Americano/genética , Insuficiência Cardíaca/genética , Hispânico ou Latino/genética , Pré-Albumina/genética , Centros Médicos Acadêmicos , Idoso , Neuropatias Amiloides Familiares/complicações , Neuropatias Amiloides Familiares/etnologia , Bancos de Espécimes Biológicos , Estudos de Casos e Controles , Estudos Transversais , Feminino , Variação Genética , Insuficiência Cardíaca/etnologia , Humanos , Masculino , Pessoa de Meia-Idade
18.
Arterioscler Thromb Vasc Biol ; 37(4): 623-632, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28153876

RESUMO

Calcific aortic valve disease (CAVD) is a highly prevalent cardiovascular disorder accounting for a rising economic and social burden on aging populations. In spite of continuing study on the pathophysiology of disease, there remain no medical therapies to prevent the progression of CAVD. The discovery of biomarkers represents a potentially complementary approach in stratifying risk and timing of intervention in CAVD and has the advantage of providing insight into causal factors for the disease. Biomarkers have been studied extensively in atherosclerotic cardiovascular disease, with success as additive for clinical and scientific purposes. Similar research in CAVD is less robust; however, the available studies of biomarkers in CAVD show promise for enhanced clinical decision making and identification of causal factors for the disease. This comprehensive review summarizes available established and novel biomarkers in CAVD, their contributions toward an understanding of pathophysiology, their potential clinical utility, and provides an outline to direct future research in the field.


Assuntos
Estenose da Valva Aórtica/sangue , Valva Aórtica/metabolismo , Valva Aórtica/patologia , Remodelação Óssea , Calcinose/sangue , Mediadores da Inflamação/sangue , Metabolismo dos Lipídeos , Remodelação Ventricular , Animais , Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/epidemiologia , Estenose da Valva Aórtica/terapia , Biomarcadores/sangue , Calcinose/epidemiologia , Calcinose/terapia , Humanos , Valor Preditivo dos Testes , Prognóstico , Fatores de Risco
19.
Heart Lung Circ ; 27(6): 745-747, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28807581

RESUMO

BACKGROUND: New-onset or worsening heart failure is the most common extra-pulmonary complication of community-acquired pneumonia (CAP) during the first 30 days after diagnosis. METHODS: We evaluated the changes in the right ventricular function amongst adult CAP survivors from the time of acute infection to its resolution. We performed comprehensive transthoracic echocardiographic examinations to assess right heart function during the acute illness and the convalescent period (4 to 6 weeks after hospital discharge). RESULTS: Twenty-six patients underwent acute measurements, of which convalescent measurements were completed in 19 subjects. There was no significant change in any of the right heart function parameters from the acute to convalescent stage of CAP. CONCLUSIONS: Our results suggest that right ventricular function does not meaningfully change in the transition from the acute to convalescent stage of CAP in non-critically ill adult CAP survivors.


Assuntos
Insuficiência Cardíaca/complicações , Ventrículos do Coração/fisiopatologia , Pneumonia/fisiopatologia , Função Ventricular Direita/fisiologia , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Infecções Comunitárias Adquiridas , Ecocardiografia , Feminino , Seguimentos , Insuficiência Cardíaca/fisiopatologia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Ontário/epidemiologia , Pneumonia/complicações , Pneumonia/epidemiologia , Prognóstico , Radiografia Torácica , Estudos Retrospectivos , Taxa de Sobrevida/tendências
20.
Clin Infect Dis ; 64(11): 1486-1493, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28205683

RESUMO

BACKGROUND.: Previous reports suggest that community-acquired pneumonia (CAP) is associated with an enhanced risk of cardiovascular complications. However, a contemporary and comprehensive characterization of this association is lacking. METHODS.: In this multicenter study, 1182 patients hospitalized for CAP were prospectively followed for up to 30 days after their hospitalization for this infection. Study endpoints included myocardial infarction, new or worsening heart failure, atrial fibrillation, stroke, deep venous thrombosis, cardiovascular death, and total mortality. RESULTS.: Three hundred eighty (32.2%) patients experienced intrahospital cardiovascular events (CVEs) including 281 (23.8%) with heart failure, 109 (9.2%) with atrial fibrillation, 89 (8%) with myocardial infarction, 11 (0.9%) with ischemic stroke, and 1 (0.1%) with deep venous thrombosis; 28 patients (2.4%) died for cardiovascular causes. Multivariable Cox regression analysis showed that intrahospital Pneumonia Severity Index (PSI) class (hazard ratio [HR], 2.45, P = .027; HR, 4.23, P < .001; HR, 5.96, P < .001, for classes III, IV, and V vs II, respectively), age (HR, 1.02, P = .001), and preexisting heart failure (HR, 1.85, P < .001) independently predicted CVEs. One hundred three (8.7%) patients died by day 30 postadmission. Thirty-day mortality was significantly higher in patients who developed CVEs compared with those who did not (17.6% vs 4.5%, P < .001). Multivariable Cox regression analysis showed that intrahospital CVEs (HR, 5.49, P < .001) independently predicted 30-day mortality (after adjustment for age, PSI score, and preexisting comorbid conditions). CONCLUSIONS.: CVEs, mainly those confined to the heart, complicate the course of almost one-third of patients hospitalized for CAP. More importantly, the occurrence of CVEs is associated with a 5-fold increase in CAP-associated 30-day mortality.


Assuntos
Doenças Cardiovasculares/complicações , Infecções Comunitárias Adquiridas/complicações , Infecções Comunitárias Adquiridas/mortalidade , Pneumonia/mortalidade , Idoso , Arritmias Cardíacas/epidemiologia , Arritmias Cardíacas/mortalidade , Doenças Cardiovasculares/mortalidade , Estudos de Coortes , Infecções Comunitárias Adquiridas/epidemiologia , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/mortalidade , Pneumonia/complicações , Pneumonia/epidemiologia , Modelos de Riscos Proporcionais , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/mortalidade
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