Activation of endothelial cells in conduit veins of dogs with heart failure and veins of normal dogs after vascular stretch by acute volume loading

Venous congestion affects neuromuscular changes in pigs in terms of muscle electrical activity and muscle stiffness

Early detection of venous congestion (VC)-related diseases such as deep vein thrombosis (DVT) is important to prevent irreversible or serious pathological conditions. However, the current way of diagnosing DVT is only possible after recognizing advanced DVT symptoms such as swelling, pain, and tightness in affected extremities, which may be due to the lack of information on neuromechanical changes following VC. Thus, the goal of this study was to investigate acute neuromechanical changes in muscle electrical activity and muscle stiffness when VC was induced. The eight pigs were selected and the change of muscle stiffness from the acceleration and muscle activity in terms of integral electromyography (IEMG) was investigated in three VC stages. Consequently, we discovered a significant increase in the change in muscle stiffness and IEMG from the baseline to the VC stages (p < 0.05). Our results and approach can enable early detection of pathological conditions associated with VC, which can be a basis for further developing early diagnostic tools for detecting VC-related diseases.

Liver lobe-specific hydrodynamic gene delivery to baboons: A preclinical trial for hemophilia gene therapy

Hydrodynamics-based gene transfer has been successfully employed for in vivo gene delivery to the liver of small animals by tail vein injection and of large animals using a computer-assisted and image-guided protocol. In an effort to develop a hydrodynamic gene delivery procedure clinically applicable for gene therapy, we have evaluated the safety and effectiveness of a lobe-specific hydrodynamic delivery procedure for hepatic gene delivery in baboons. Reporter plasmid was used to assess the gene delivery efficiency of the lobe-specific hydrodynamic gene delivery, and plasmid-carrying human factor IX gene was used to examine the pattern of long-term gene expression. The results demonstrated liver lobe-specific gene delivery, therapeutic levels of human factor IX gene expression lasting for >100 days, and the efficacy of repeated hydrodynamic gene delivery into the same liver lobes. Other than a transient increase in blood concentration of liver enzymes right after the injection, no significant adverse events were observed in animals during the study period. The results obtained from this first non-human primate study support the clinical applicability of the procedure for lobe-specific hydrodynamic gene delivery to liver.

Pathophysiology-Based Management of Acute Heart Failure

Even though acute heart failure (AHF) is one of the most common admission diagnoses globally, its pathogenesis is poorly understood, and there are few effective treatments available. Despite an heterogenous onset, congestion is the leading contributor to hospitalization, making it a crucial therapeutic target. Complete decongestion, nevertheless, may be hard to achieve, especially in patients with reduced end organ perfusion. In order to promote a personalised pathophysiological-based therapy for patients with AHF, we will address in this review the pathophysiological principles that underlie the clinical symptoms of AHF as well as examine how to assess them in clinical practice, suggesting that gaining a deeper understanding of pathophysiology might result in significant improvements in HF therapy.

Cardiac Spinal Afferent Denervation Attenuates Renal Dysfunction in Rats With Cardiorenal Syndrome Type 2

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Epicardial application of RTX at the time of MI largely prevented renal dysfunction, attenuated renal congestion, and partially restored renal blood flow in rats with CHF.

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RNA sequencing analysis showed that renal injury, inflammation, hypoxia, and apoptosis genes were significantly up-regulated in the renal tissue of CHF rats, which was largely prevented by epicardial RTX at the time of MI.

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Cardiac afferent ablation by intra–stellate ganglia injection of RTX or unilateral renal denervation 4 weeks after MI had similar renal protective effects on renal tubular damage in CHF rats.

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These data provide evidence for cardiac spinal afferent modulation of renal function and a potential targeted therapy.

Cardiorenal syndrome type 2 (CRS2) is defined as a chronic cardiovascular disease, usually chronic heart failure (CHF), resulting in chronic kidney disease. We hypothesized that the cardiac spinal afferent reflex (CSAR) plays a critical role in the development of CRS2. Our data suggest that cardiac afferent ablation by resiniferatoxin not only improves cardiac function but also benefits the kidneys and increases long-term survival in the myocardial infarction model of CHF. We also found that renal denervation has a similar reno-protective effect in CHF rats. We believe this novel work contributes to the development of a unique neuromodulation therapy to treat CHF patients.

Direct Evidence of Endothelial Dysfunction and Glycocalyx Loss in Dermal Biopsies of Patients With Chronic Kidney Disease and Their Association With Markers of Volume Overload

Cardiovascular morbidity is a major problem in patients with chronic kidney disease (CKD) and endothelial dysfunction (ED) is involved in its development. The luminal side of the vascular endothelium is covered by a protective endothelial glycocalyx (eGC) and indirect evidence indicates eGC loss in CKD patients. We aimed to investigate potential eGC loss and ED in skin biopsies of CKD patients and their association with inflammation and volume overload. During living kidney transplantation procedure, abdominal skin biopsies were taken from 11 patients with chronic kidney disease stage 5 of whom 4 were treated with hemodialysis and 7 did not receive dialysis treatment. Nine healthy kidney donors served as controls. Biopsies were stained and quantified for the eGC marker Ulex europaeus agglutinin-1 (UEA1) and the endothelial markers vascular endothelial growth factor-2 (VEGFR2) and von Willebrand factor (vWF) after double staining and normalization for the pan-endothelial marker cluster of differentiation 31. We also studied associations between quantified log-transformed dermal endothelial markers and plasma markers of inflammation and hydration status. Compared to healthy subjects, there was severe loss of the eGC marker UEA1 (P < 0.01) while VEGFR2 was increased in CKD patients, especially in those on dialysis (P = 0.01). For vWF, results were comparable between CKD patients and controls. Skin water content was identical in the three groups, which excluded dermal edema as an underlying cause in patients with CKD. The dermal eGC/ED markers UEA1, VEGFR2, and vWF all associated with plasma levels of NT-proBNP and sodium (all R² > 0.29 and P < 0.01), except for vWF that only associated with plasma NT-proBNP. This study is the first to show direct histopathological evidence of dermal glycocalyx loss and ED in patients with CKD. In line with previous research, our results show that ED associates with markers of volume overload arguing for strict volume control in CKD patients.

The predominance and diagnostic value of neutrophils in differentiating transudates and exudates in dogs

BACKGROUND

There is disagreement in the literature about the proportion of neutrophils expected in canine transudates. A cutoff of <30% neutrophils has been recommended for distinguishing transudates from exudates, but its validity has not been established.

OBJECTIVE

The aim of this study was to evaluate differential cell counts in canine effusions and analyze the percentage and number of neutrophils in transudates and exudates.

METHODS

Effusion data were obtained retrospectively from 263 dogs with pleural or peritoneal effusion. Low-protein transudates, high-protein transudates, and exudates were classified using the total protein (TP) concentration and total nucleated cell count (TNCC). Differential percentages and absolute neutrophil counts were compared by the effusion type and underlying etiology.

RESULTS

Low-protein transudates (n = 63), high-protein transudates (n = 84), and exudates (n = 77) had a median (range) of 35% (0%-100%), 59% (0%-100%), and 90% (50%-98%) neutrophils (P < .0001). All effusions with <50% neutrophils were transudates, but 53% of transudates had ≥50% neutrophils, and 69% had ≥30%. Median neutrophil counts were 62/µL (0-892/µL), 538/µL (0-4550/µL), and 45 590/µL (5400-496 800/µL) in low-protein transudates, high-protein transudates, and exudates, respectively (P < .0001). Neutrophil counts correlated with TNCC (r²  = 0.99), such that using neutrophil cutoffs did not affect effusion classifications in most cases. Neutrophil percentages and counts were higher in effusions from dogs with uroabdomen and sepsis (P < .01); neutrophil counts were lower in dogs with hepatic insufficiency (P < .0001). Uroabdomen usually caused low-protein, high-neutrophil exudates.

CONCLUSIONS

Although effusions with <50% neutrophils are transudates, most transudates and exudates have ≥50% neutrophils, limiting the diagnostic usefulness of % neutrophils for classifying effusions. Absolute neutrophil cutoffs did not notably improve effusion classification but could warrant future studies.

Fibrosis, the Bad Actor in Cardiorenal Syndromes: Mechanisms Involved

Cardiorenal syndrome is a term that defines the complex bidirectional nature of the interaction between cardiac and renal disease. It is well established that patients with kidney disease have higher incidence of cardiovascular comorbidities and that renal dysfunction is a significant threat to the prognosis of patients with cardiac disease. Fibrosis is a common characteristic of organ injury progression that has been proposed not only as a marker but also as an important driver of the pathophysiology of cardiorenal syndromes. Due to the relevance of fibrosis, its study might give insight into the mechanisms and targets that could potentially be modulated to prevent fibrosis development. The aim of this review was to summarize some of the pathophysiological pathways involved in the fibrotic damage seen in cardiorenal syndromes, such as inflammation, oxidative stress and endoplasmic reticulum stress, which are known to be triggers and mediators of fibrosis.

Intraoperative venous congestion and acute kidney injury in cardiac surgery: an observational cohort study

BACKGROUND

Increased intravascular volume has been associated with protection from acute kidney injury (AKI), but in patients with congestive heart failure, venous congestion is associated with increased AKI. We tested the hypothesis that intraoperative venous congestion is associated with AKI after cardiac surgery.

METHODS

In patients enrolled in the Statin AKI Cardiac Surgery trial, venous congestion was quantified as the area under the curve (AUC) of central venous pressure (CVP) >12, 16, or 20 mm Hg during surgery (mm Hg min). AKI was defined using Kidney Disease Improving Global Outcomes (KDIGO) criteria and urine concentrations of tissue inhibitor of metalloproteinase-2 and insulin-like growth factor binding protein 7 ([TIMP-2]⋅[IGFBP7]), a marker of renal stress. We measured associations between venous congestion, AKI and [TIMP-2]⋅[IGFBP7], adjusted for potential confounders. Values are reported as median (25th-75th percentile).

RESULTS

Based on KDIGO criteria, 104 of 425 (24.5%) patients developed AKI. The venous congestion AUCs were 273 mm Hg min (81-567) for CVP >12 mm Hg, 66 mm Hg min (12-221) for CVP >16 mm Hg, and 11 mm Hg min (1-54) for CVP >20 mm Hg. A 60 mm Hg min increase above the median venous congestion AUC above each threshold was independently associated with increased AKI (odds ratio=1.06; 95% confidence interval [CI], 1.02-1.10; P=0.008; odds ratio=1.12; 95% CI, 1.02-1.23; P=0.013; and odds ratio=1.30; 95% CI, 1.06-1.59; P=0.012 for CVP>12, >16, and >20 mm Hg, respectively). Venous congestion before cardiopulmonary bypass was also associated with increased [TIMP-2]⋅[IGFBP7] measured during cardiopulmonary bypass and after surgery, but neither venous congestion after cardiopulmonary bypass nor venous congestion throughout surgery was associated with postoperative [TIMP-2]⋅[IGFBP7].

CONCLUSION

Intraoperative venous congestion was independently associated with increased AKI after cardiac surgery.

Renal dysfunction in cardiovascular diseases and its consequences

It is well known that the heart and kidney and their synergy is essential for hemodynamic homeostasis. Since the early XIX century it has been recognized that cardiovascular and renal diseases frequently coexist. In the nephrological field, while it is well accepted that renal diseases favor the occurrence of cardiovascular diseases, it is not always realized that cardiovascular diseases induce or aggravate renal dysfunctions, in this way further deteriorating cardiac function and creating a vicious circle. In the same clinical field, the role of venous congestion in the pathogenesis of renal dysfunction is at times overlooked. This review carefully quantifies the prevalence of chronic and acute kidney abnormalities in cardiovascular diseases, mainly heart failure, regardless of ejection fraction, and the consequences of renal abnormalities on both organs, making cardiovascular diseases a major risk factor for kidney diseases. In addition, with regard to pathophysiological aspects, we attempt to substantiate the major role of fluid overload and venous congestion, including renal venous hypertension, in the pathogenesis of acute and chronic renal dysfunction occurring in heart failure. Furthermore, we describe therapeutic principles to counteract the major pathophysiological abnormalities in heart failure complicated by renal dysfunction. Finally, we underline that the mild transient worsening of renal function after decongestive therapy is not usually associated with adverse prognosis. Accordingly, the coexistence of cardiovascular and renal diseases inevitably means mediating between preserving renal function and improving cardiac activity to reach a better outcome.

Right Heart Failure and Cardiorenal Syndrome

Cardiorenal syndrome is a complex interplay of dysregulated heart and kidney interaction that leads to multiorgan system dysfunction, which is not an uncommon occurrence in the setting of right heart failure. The traditional concept of impaired perfusion and forward flow recently has been modified to include the recognition of systemic venous congestion as a contributor, with direct and indirect mechanisms, including elevated renal venous pressure, reduced renal perfusion pressure, increased renal interstitial pressure, tubular dysfunction, splanchnic congestion, and neurohormonal and inflammatory activation. Treatment options beyond diuretics and vasoactive drugs remain limited and lack supportive evidence.

Reinterpreting Renal Hemodynamics: The Importance of Venous Congestion and Effective Organ Perfusion in Acute Kidney Injury

The significance of effective renal perfusion is relatively underemphasized in the current literature. From a renal standpoint, besides optimizing cardiac output, renal perfusion should be maximized as well. Among the several additional variables of the critically ill, such as intra-abdominal pressure, the presence of venous congestion and elevated central venous pressures, airway pressures generated by mechanical ventilation do affect net renal perfusion. These forces represent both a potential danger and an ongoing opportunity to improve renal outcomes in the critically ill and an opportunity to move beyond the simplified viewpoint of optimizing volume status. Therefore, to optimize nephron-protective therapies, nephrologists and intensive care physicians should be familiar with the concept of net renal perfusion pressure. This review appraises the background literature on renal perfusion pressure, including the initial animal data and historical human studies up to the most current developments in the field, exploring potential avenues to assess and improve renal blood supply.

High central venous pressure is associated with acute kidney injury and mortality in patients underwent cardiopulmonary bypass surgery

PURPOSE

We sought to investigate the relationship between high CVP, AKI, and mortality in patients undergoing cardiac surgery with cardiopulmonary bypass.

MATERIALS

All patients aged 18 years or older who underwent cardiac surgery with CPB were prospectively reviewed. Patients were excluded when renal artery were involved before and during surgery. Patients were dichotomized into high CVP group(>10 mmHg) and low CVP group(<10 mmHg). All patients were followed by telephone.

RESULTS

A total of 1941 patients were included in observed study. In high CVP group, three hundred forty-seven patients (43.32%) developed AKI, while eighty-six (7.543%) in low CVP group(P <0.0001). Furthermore, in every KDIGO stage, patients of AKI in high CVP group were more than those in low CVP group(P <0.0001). The incidence of AKI increased as CVP increased, especially when CVP was higher than 10cmH2O. In a median follow-up time of 9.2 months, Crude mortality is 8.365% in the high CVP group compared to 1.929% in the low CVP group (p<0.0001). In multivariate analysis, CVP remained the independent predictor of survival.

CONCLUSIONS

High CVP is associated with AKI , and it is independently related to all-cause mortality in patients underwent cardiovascular surgery with cardiopulmonary bypass.

Venous congestion, endothelial and neurohormonal activation in acute decompensated heart failure: cause or effect?

Venous congestion and endothelial and neurohormonal activation are known to occur in acute decompensated heart failure (ADHF), yet the temporal role of these processes in the pathophysiology of decompensation is not fully understood. Conventional wisdom presumes congestion to be a consequence of worsening cardiovascular function; however, the biomechanically driven effects of venous congestion are biologically plausible contributors to ADHF that remain largely unexplored in vivo. Recent experimental evidence from human models suggests that fluid accumulation and venous congestion are not simply consequences of poor cardiovascular function, but rather are fundamental pro-oxidant, pro-inflammatory, and hemodynamic stimuli that contribute to acute decompensation. The latest advances in the monitoring of volume status using implantable devices allow for the detection of venous congestion before symptoms arise. This may ultimately lead to improved treatment strategies including not only diuretics, but also specific, adjuvant interventions to counteract endothelial and neurohormonal activation during early preclinical decompensation.

Agents with vasodilator properties in acute heart failure: how to design successful trials

Agents with vasodilator properties (AVDs) are frequently used in the treatment of acute heart failure (AHF). AVDs rapidly reduce preload and afterload, improve left ventricle to aorta and right ventricle to pulmonary artery coupling, and may improve symptoms. Early biomarker changes after AVD administration have suggested potentially beneficial effects on cardiac stretch, vascular tone, and renal function. AVDs that reduce haemodynamic congestion without causing hypoperfusion might be effective in preventing worsening organ dysfunction. Existing AVDs have been associated with different results on outcomes in randomized clinical trials, and observational studies have suggested that AVDs may be associated with a clinical outcome benefit. Lessons have been learned from past AVD trials in AHF regarding preventing hypotension, selecting the optimal endpoint, refining dyspnoea measurements, and achieving early randomization and treatment initiation. These lessons have been applied to the design of ongoing pivotal clinical trials, which aim to ascertain if AVDs improve clinical outcomes. The developing body of evidence suggests that AVDs may be a clinically effective therapy to reduce symptoms, but more importantly to prevent end-organ damage and improve clinical outcomes for specific patients with AHF. The results of ongoing trials will provide more clarity on the role of AVDs in the treatment of AHF.

Safety assessment of liver-targeted hydrodynamic gene delivery in dogs

Evidence in support of safety of a gene delivery procedure is essential toward gene therapy. Previous studies using the hydrodynamics-based procedure primarily focus on gene delivery efficiency or gene function analysis in mice. The current study focuses on an assessment of the safety of computer-controlled and liver-targeted hydrodynamic gene delivery in dogs as the first step toward hydrodynamic gene therapy in clinic. We demonstrate that the impacts of the hydrodynamic procedure were limited in the injected region and the influences were transient. Histological examination and the hepatic microcirculation measurement using reflectance spectrophotometry reveal that the liver-specific impact of the procedure involves a transient expansion of the liver sinusoids. No systemic damage or toxicity was observed. Physiological parameters, including electrocardiogram, heart rate, blood pressure, oxygen saturation, and body temperature, remained in normal ranges during and after hydrodynamic injection. Body weight was also examined to assess the long-term effects of the procedure in animals who underwent 3 hydrodynamic injections in 6 weeks with 2-week time interval in between. Serum biochemistry analysis showed a transient increase in liver enzymes and a few cytokines upon injection. These results demonstrate that image-guided, liver-specific hydrodynamic gene delivery is safe.

Acute mechanical stretch promotes eNOS activation in venous endothelial cells mainly via PKA and Akt pathways

In the vasculature, physiological levels of nitric oxide (NO) protect against various stressors, including mechanical stretch. While endothelial NO production in response to various stimuli has been studied extensively, the precise mechanism underlying stretch-induced NO production in venous endothelial cells remains incompletely understood. Using a model of continuous cellular stretch, we found that stretch promoted phosphorylation of endothelial NO synthase (eNOS) at Ser¹¹⁷⁷, Ser⁶³³ and Ser⁶¹⁵ and NO production in human umbilical vein endothelial cells. Although stretch activated the kinases AMPKα, PKA, Akt, and ERK1/2, stretch-induced eNOS activation was only inhibited by kinase-specific inhibitors of PKA and PI3K/Akt, but not of AMPKα and Erk1/2. Similar results were obtained with knockdown by shRNAs targeting the PKA and Akt genes. Furthermore, inhibition of PKA preferentially attenuated eNOS activation in the early phase, while inhibition of the PI3K/Akt pathway reduced eNOS activation in the late phase, suggesting that the PKA and PI3K/Akt pathways play distinct roles in a time-dependent manner. Finally, we investigated the role of these pathways in stretch-induced endothelial exocytosis and leukocyte adhesion. Interestingly, we found that inhibition of the PI3K/Akt pathway increased stretch-induced Weibel-Palade body exocytosis and leukocyte adhesion, while inhibition of the PKA pathway had the opposite effects, suggesting that the exocytosis-promoting effect of PKA overwhelms the inhibitory effect of PKA-mediated NO production. Taken together, the results suggest that PKA and Akt are important regulators of eNOS activation in venous endothelial cells under mechanical stretch, while playing different roles in the regulation of stretch-induced endothelial exocytosis and leukocyte adhesion.

A re-appraisal of volume status and renal function impairment in chronic heart failure: combined effects of pre-renal failure and venous congestion on renal function

The association between cardiac failure and renal function impairment has gained wide recognition over the last decade. Both structural damage in the form of systemic atherosclerosis and (patho) physiological hemodynamic changes may explain this association. As regards hemodynamic factors, renal impairment in chronic heart failure is traditionally assumed to be mainly due to a decrease in cardiac output and a subsequent decrease in renal perfusion. This will lead to a decrease in glomerular filtration rate and a compensatory increase in tubular sodium retention. The latter is a physiological renal response aimed at retaining fluids in order to increase cardiac filling pressure and thus renal perfusion. In heart failure, however, larger increases in cardiac filling pressure are needed to restore renal perfusion and thus more volume retention. In this concept, in chronic heart failure, an equilibrium exists where a certain degree of congestion is the price to be paid to maintain adequate renal perfusion and function. Recently, this hypothesis was challenged by new studies, wherein it was found that the association between right-sided cardiac filling pressures and renal function is bimodal, with worse renal function at the highest filling pressures, reflecting a severely congested state. Renal hemodynamic studies suggest that congestion negatively affects renal function in particular in patients in whom renal perfusion is also compromised. Thus, an interplay between cardiac forward failure and backward failure is involved in the renal function impairment in the congestive state, presumably along with other factors. Only few data are available on the impact of intervention in volume status on the cardio-renal interaction. Sparse data in cardiac patients as well as evidence from cohorts with primary renal disease suggest that specific targeting of volume overload may be beneficial for long-term outcome, in spite of a certain further decrease in renal function, at least in the context of current treatment where possible reflex neurohumoral activation is ameliorated by the background treatment by blockers of the renin-angiotensin-aldosterone system.

Inflammatory activation: cardiac, renal, and cardio-renal interactions in patients with the cardiorenal syndrome

Although inflammation is a physiologic response designed to protect us from infection, when unchecked and ongoing it may cause substantial harm. Both chronic heart failure (CHF) and chronic kidney disease (CKD) are known to cause elaboration of several pro-inflammatory mediators that can be detected at high concentrations in the tissues and blood stream. The biologic sources driving this chronic inflammatory state in CHF and CKD are not fully established. Traditional sources of inflammation include the heart and the kidneys which produce a wide range of pro-inflammatory cytokines in response to neurohormones and sympathetic activation. However, growing evidence suggests that non-traditional biomechanical mechanisms such as venous and tissue congestion due to volume overload are also important as they stimulate endotoxin absorption from the bowel and peripheral synthesis and release of pro-inflammatory mediators. Both during the chronic phase and, more rapidly, during acute exacerbations of CHF and CKD, inflammation and congestion appear to amplify each other resulting in a downward spiral of worsening cardiac, vascular, and renal functions that may negatively impact patients' outcome. Anti-inflammatory treatment strategies aimed at attenuating end organ damage and improving clinical prognosis in the cardiorenal syndrome have been disappointing to date. A new therapeutic paradigm may be needed, which involves different anti-inflammatory strategies for individual etiologies and stages of CHF and CKD. It may also include specific (short-term) anti-inflammatory treatments that counteract inflammation during the unsettled phases of clinical decompensation. Finally, it will require greater focus on volume overload as an increasingly significant source of systemic inflammation in the cardiorenal syndrome.

Renal dysfunction in heart failure

Renal dysfunction is a common, important comorbidity in patients with both chronic and acute heart failure (HF). Chronic kidney disease and worsening renal function (WRF) are associated with worse outcomes, but our understanding of the complex bidirectional interactions between the heart and kidney remains poor. When addressing these interactions, one must consider the impact of intrinsic renal disease resulting from medical comorbidities on HF outcomes. WRF may result from any number of important processes. Understanding the role of each of these factors and their interplay are essential in understanding how to improve outcomes in patients with renal dysfunction and HF.

Venous congestion and endothelial cell activation in acute decompensated heart failure

Despite accumulating clinical evidence supporting a key role for venous congestion in the development of acute decompensated heart failure (ADHF), there remain several gaps in our knowledge of the pathophysiology of ADHF. Specifically, the biomechanically driven effects of venous congestion on the vascular endothelium (the largest endocrine/paracrine organ of the body), on neurohormonal activation, and on renal and cardiac dysfunction remain largely unexplored. We propose that venous congestion is a fundamental, hemodynamic stimulus for vascular inflammation, which plays a key role in the development and possibly the resolution of ADHF through vascular, humoral, renal, and cardiac mechanisms. A better understanding of the role of venous congestion and endothelial activation in the pathophysiology of ADHF may provide a strong rationale for near-future testing of treatment strategies that target biomechanically driven inflammation. Targeting vascular and systemic inflammation before symptoms arise may prevent progression to overt clinical decompensation in the ADHF syndrome.