Evaluation of hemostatic and fibrinolytic markers in dogs with ascites attributable to right-sided congestive heart failure

N-terminal brain natriuretic peptide, cardiac troponin-I, and point-of-care ultrasound in dogs with cardiac and noncardiac causes of nonhemorrhagic ascites

BACKGROUND

Nonhemorrhagic ascites (NHA) can be caused by cardiac diseases (cNHA) and noncardiac diseases (ncNHA). N-terminal brain natriuretic peptide (NT-proBNP), cardiac troponin-I (cTnI), and point-of-care ultrasound (POCUS) may differentiate between cNHA and ncNHA.

HYPOTHESIS/OBJECTIVES

We compared NT-proBNP and cTnI concentrations as well as POCUS findings in dogs presented with cNHA and ncNHA.

ANIMALS

Dogs (n = 60) were enrolled based on identification of NHA with an effusion packed cell volume < 10%.

METHODS

Blood samples were collected and POCUS was performed on all dogs. Dogs were diagnosed with cNHA (n = 28) or ncNHA (n = 32) based on echocardiography. The cNHA group was subdivided into cardiac non-pericardial disease (n = 17) and pericardial disease (n = 11).

RESULTS

The NT-proBNP concentration (median; range pmol/L) was significantly higher in the cNHA group (4510; 250-10 000) compared to the ncNHA group (739.5; 250-10 000; P = .01), with a sensitivity of 53.8% and specificity of 85.7% using a cut-off of 4092 pmol/L. The NT-proBNP concentrations were significantly higher in the cardiac non-pericardial disease group (8339; 282-10 000) compared with the pericardial disease group (692.5; 250-4928; P = .002). A significant difference in cTnI concentration (median; range ng/L) between the cNHA group (300; 23-112 612) and ncNHA group (181; 17-37 549) was not detected (P = .41). A significantly higher number of dogs had hepatic venous and caudal vena cava distension in the cNHA group compared to the ncNHA group, respectively (18/28 vs 3/29, P < .0001 and 13/27 vs 2/29, P < .001). Gall bladder wall edema was not significantly different between groups (4/28 vs 3/29, P = .74).

CONCLUSIONS AND CLINICAL IMPORTANCE

NT-proBNP concentration and POCUS help distinguish between cNHA and ncNHA.

Fibrinolysis in Dogs with Intracavitary Effusion: A Review

Simple Summary

In blood vessels there is a balance between clot formation and its dissolution. Fibrinolysis normally allows the breakdown of blood clots during the healing of injured blood vessels. This process is mediated by the activation of a blood enzyme (plasmin) which breaks down a meshed protein (fibrin) which holds blood clots at the site of the vessel injury. In some diseases, the activation of plasmin becomes excessive, leading to bleeding tendencies (hyperfibrinolysis). Under normal conditions, abdominal and thoracic cavities are filled with a small amount of fluid deriving from the blood. The results of recent studies have shown that, in dogs, all types of pathologic intracavitary fluids have an increased fibrinolytic activity. This increased fibrinolytic activity is also present in their blood, in some cases reaching a hyperfibrinolytic state. Hyperfibrinolysis and bleeding tendencies have also been documented in cardiopathic dogs with ascites. The latter result is surprising considering that thrombotic events are commonly documented in humans and cats with some cardiac diseases.

Abstract

Physiologic fibrinolysis is a localized process in which stable fibrin strands are broken down by plasmin in response to thrombosis. Plasmin activation can also take place separately from the coagulation process, resulting in pathologic fibrinolysis. When plasmin activation exceeds the neutralizing capacity of plasmin inhibitors, severe bleeding can potentially take place. Although the processes which regulate coagulation and fibrinolysis in the blood are well known, it is less clear as to what extent the same processes take place in the body cavities and whether they influence systemic hemostasis. The results of the studies herein cited demonstrate that coagulation followed by fibrinogenolytic/fibrinolytic activity takes place in all kinds of canine ascitic and pleural fluids. Moreover, systemic clotting abnormalities suggesting primary fibrinolysis/primary hyperfibrinolysis (i.e., elevated plasma fibrin/fibrinogen degradation products [FDPs] and normal D-dimer concentrations with fibrinogen concentrations ≤ 100 mg/dL or above this cut-off, respectively) occur in dogs with intracavitary effusion. Enhanced fibrinolytic activity in dogs with intracavitary effusion can also be detected using rotational thromboelastometry (ROTEM), although the degree of agreement between ROTEM and FDPs, D-dimer and fibrinogen concentrations is poor. Finally, contrary to the thrombotic events commonly documented in some humans and cats with cardiac diseases, bleeding tendencies due to primary fibrinolysis/primary hyperfibrinolysis have been documented in dogs with cardiogenic ascites.

Percutaneous Balloon Dilation in Two Dogs with Cor Triatriatum Dexter

Percutaneous balloon dilation was performed in a Rhodesian Ridgeback and in an American Staffordshire Terrier affected by cor triatriatum dexter (CTD). Both cases had ascites without jugular venous distension or pleural effusion. In both dogs the CTD presented a perforated membrane but with different morphology: in one case the coronary sinus entered the caudal chamber of the CTD together with the caudal vena cava. In the other case, the coronary sinus communicated with the cranial chamber of the CTD together with the cranial vena cava. Percutaneous balloon dilation of the CTD was successfully performed, and both dogs had uneventful surgery recoveries. At two years of follow-up, the dogs were free from clinical signs and cardiac medication.

Reduced risk of arterial thromboembolism in cats with pleural effusion due to congestive heart failure

OBJECTIVES

The aim of the study was to determine whether cardiogenic pleural effusion in cats is associated with a lower risk of arterial thromboembolism (ATE) compared with cats with cardiac disease without evidence of pleural effusion.

METHODS

A cross-sectional study was conducted on owned cats with natural occurring cardiac diseases. Cats included were classified in three groups: those with cardiac disease but no evidence of congestive heart failure (CHF); those with evidence of cardiogenic pulmonary oedema; and those with evidence of cardiogenic pleural effusion. Prevalence of ATE was calculated and the variables analysed for an association with this outcome were the presence and type of CHF, sex and neuter status, age, breed, type of cardiac diseases and left atrial (LA) dimension. A multivariable logistic regression model was used to fit the association between ATE and these variables.

RESULTS

A total of 366 cats with cardiac disease met the inclusion criteria: 179 were included in the group with cardiac disease but no evidence of CHF, 66 in the group with evidence of cardiogenic pulmonary oedema and 121 in the group with evidence of cardiogenic pleural effusion. Prevalence of ATE (58/366 [15.8%]) was significantly different among groups (with no evidence of CHF, 28/179 [15.6%]; with evidence of cardiogenic pulmonary oedema, 22/66 [33.3%]; with evidence of cardiogenic pleural effusion, 8/121 [6.6%]; P <0.001). Cats with ATE had a significantly higher LA to aortic root ratio (2.30 ± 0.46) than those without ATE (2.04 ± 0.46; P <0.001). Multivariable logistic regression analysis indicated that the group with evidence of cardiogenic pleural effusion was associated with a lower risk of developing ATE compared with groups with cardiac disease but no evidence of CHF and with evidence of cardiogenic pulmonary oedema (P = 0.005 and P <0.001, respectively).

CONCLUSIONS AND RELEVANCE

Presence of cardiogenic pleural effusion is associated with a lower risk of developing ATE, while LA enlargement is a risk factor for ATE.

Enhanced fibrinolysis detection in a natural occurring canine model with intracavitary effusions: Comparison and degree of agreement between thromboelastometry and FDPs, D-dimer and fibrinogen concentrations

Dogs with intracavitary effusion have coagulative abnormalities indicative of primary fibrinolysis/hyperfibrinolysis. The aim of this case control study was to investigate by rotational thromboelastometry (ROTEM) and standard coagulation tests (fibrin-fibrinogen degradation products, D-dimer and fibrinogen) fibrinolysis in dogs with intracavitary effusions. Thirty-two dogs with intracavitary effusion and 32 control sick dogs without effusion were studied. Frequency of fibrinolysis grade of severity (i.e., hypofibrinolysis/basal fibrinolysis vs increased fibrinolysis vs hyperfibrinolysis) by ROTEM and standard coagulation tests were compared between groups. Pattern of fibrinolysis by ROTEM (i.e., late vs intermediate vs fulminant) and type of fibrinolysis by standard coagulation tests (i.e., hypofibrinolysis/basal fibrinolysis vs primary fibrinolysis vs secondary fibrinolysis vs primary hyperfibrinolysis vs secondary hyperfibrinolysis) were also compared between groups. Dogs with intracavitary effusion had a lesser degree of hypofibrinolysis and basal fibrinolysis and a higher degree of increased fibrinolysis and hyperfibrinolysis compared to controls, both by ROTEM and by standard coagulation tests (P = 0.042 and P = 0.017, respectively). Nevertheless, there was a poor agreement between the two classification schemes (34.4%, K = 0.06, 95% CI = -0.14 ‒ +0.26). Dogs with intracavitary effusion showed, by ROTEM, a lesser degree of hypofibrinolysis and basal fibrinolysis and a higher degree of late, intermediate, and fulminant fibrinolysis compared to controls (P = 0.044). Finally, dogs with intracavitary effusion had, by standard coagulation tests, a higher frequency of primary fibrinolysis and primary hyperfibrinolysis and a lower frequency of secondary fibrinolysis compared to controls. Dogs with intracavitary effusion showed an increased frequency and a different and more severe pattern of fibrinolysis compared to controls.

Characteristics of hyperfibrinolysis in dogs and cats demonstrated by rotational thromboelastometry (ROTEM)

Hyperfibrinolysis (HFL) is a pathophysiological mechanism that has not been described in dogs or cats extensively. The aim of this study was to describe rotational thromboelastometry (ROTEM) parameters and underlying diagnosis in dogs and cats with HFL and evaluate association with bleeding diathesis. The ROTEM database was retrospectively searched for EXTEM (ROTEM activated with proprietary tissue factor) tracings with maximum lysis at 60min ≥15%. Concurrent ROTEM and plasma coagulation tests, thrombocyte number, diagnosis and survival to hospital discharge were extracted from medical records. Analysis of differences between dogs and cats and of factors associated with bleeding, fulminant HFL (clot breakdown within 30min) and survival to hospital discharge were performed. Hyperfibrinolysis was detected in eight cats presenting with haemoabdomen or haemothorax (n=4/8, 50%) and trauma (n=3/8, 38%) and in 36 dogs with angiostrongylosis (n=12, 33%), neoplasia (n=7, 19%), liver disease (n=4, 11%) and others including apparently healthy dogs (n=3, 8%). Hyperfibrinolysis was associated with prolonged EXTEM and APTEM (EXTEM with added apoprotein for inhibition of HFL) clotting time and decreased FIBTEM (EXTEM with added cytochalasin D for inhibition of thrombocytes) maximum clot firmness (MCF) in dogs and cats and with decreased EXTEM MCF in dogs. Bleeding dogs had significantly hypocoagulable EXTEM tracings. Fulminant HFL was associated with severe hypofibrinogenaemia in dogs (P=0.005) and was not associated with survival to hospital discharge. Evidence of HFL was demonstrated in dogs and cats with bleeding, trauma, parasitic and neoplastic disease. HFL is associated with late and weak clot formation.

Hemostatic findings of pleural fluid in dogs and the association between pleural effusions and primary hyperfibrino(geno)lysis: A cohort study of 99 dogs

The primary objective of this study was to determine if activation of coagulation and fibrinolysis occurs in canine pleural effusions. Thirty-three dogs with pleural effusions of different origin were studied. Pleural effusion fibrinogen concentrations were significantly lower, while pleural fibrin-fibrinogen degradation products (FDPs) and D-dimer concentrations were significantly higher than those in plasma (P < 0.001 for all comparisons). These results show that, in canine pleural fluids, there is evidence of coagulation activation and fibrinolysis. The secondary aims of the current study were to determine if primary hyperfibrinolysis ([PHF] i.e., elevated plasma FDPs with a normal D-dimer concentrations), occurs in dogs with pleural effusion, and whether the presence of a concurrent inflammatory process may have activated the hemostatic cascade, with its intrinsically linked secondary hyperfibrinolysis, masking the concurrent PHF. The previously 33 selected dogs with pleural effusion (group 1) were compared to two control groups of 33 healthy (group 2) and 33 sick dogs without pleural effusion (group 3). Serum fibrinogen, FDPs, D-dimer, C-reactive protein (CRP), fibrinogen/CRP ratio, and frequency of PHF were determined. Fibrinogen, FDPs, D-dimer and CRP concentrations in group 1 were significantly increased compared to group 2 (P < 0.001 for all comparisons). FDPs and CRP concentrations in group 1 were also significantly increased compared to group 3 (P = 0.001 and P < 0.001, respectively). The fibrinogen/CRP ratio was significantly decreased in group 1 compared to groups 2 and 3 (P < 0.001 for both comparison). The frequency of PHF was significantly higher in group 1 compared to groups 2 (P = 0.004), but not compared to group 3. These results support the hypothesis that PHF occurs significantly more often in dogs with pleural effusion compared to healthy dogs. Nevertheless, the decrease in the fibrinogen/CRP ratio in group 1 compared to group 3, considering the higher FDPs and similar D-dimer concentrations, would suggest that PHF is also more frequent in dogs with pleural effusion compared to sick control dogs, and that this phenomenon is hidden due to concurrent secondary hyperfibrinolysis.

Hemostatic Findings in Ascitic Fluid: A Cross-Sectional Study in 70 Dogs

BACKGROUND

Ascitic fluids of horses and humans have fibrinolytic activity, independent of the underlying mechanism of fluid formation.

OBJECTIVE

To determine whether coagulation and fibrinogenolytic/fibrinolytic activity (ie, low fibrinogen and increased fibrin-fibrinogen degradation products [FDPs], D-dimer, or both) occur in all types of ascitic fluid in dogs.

ANIMALS

A total of 70 client-owned dogs with ascites.

METHODS

In this cross-sectional study, dogs were categorized based on the pathophysiology of fluid formation into 4 groups: transudates due to decreased osmotic pressure, transudates due to increased hydrostatic pressure, exudates, and hemorrhagic ascites. Fibrinogen, FDPs, and D-dimer concentrations were measured and then compared in both ascitic fluid and plasma.

RESULTS

Ten dogs had transudates due to decreased colloid osmotic pressure, 18 had transudates due to increased hydrostatic pressure, 13 had exudates, and 29 had hemorrhagic ascites. Ascitic fibrinogen concentrations (n = 70) were significantly lower (median = 59 mg/dL; range: 59-122 mg/dL) than those in the plasma (median = 168 mg/dL, range: 59-879 mg/dL; P < .0001). Ascitic FDPs concentrations (n = 70) were significantly higher (<5 μg/mL: 3/70 dogs, ≥5 to <20 μg/mL: 11/70 dogs, ≥20 μg/mL: 56/70 dogs) than those in the plasma (<5 μg/mL: 17/70 dogs, ≥5 to <20 μg/mL: 28/70 dogs, ≥20 μg/mL: 25/70 dogs; P < .0001). Ascitic D-dimer concentrations (n = 70) were significantly higher (median = 3.98 μg/mL, range: 0.02-9.19) than those in the plasma (median = 0.11 μg/mL, range: 0.01-4.08; P < .0001). Analysis of the data for each of the 4 different types of ascites showed similar results to those of all the data analyzed together.

CONCLUSIONS AND CLINICAL IMPORTANCE

Ascitic fluid of dogs has evidence of coagulation activation and fibrinogenolytic/fibrinolytic activity and that this phenomenon occurs independent of the underlying mechanism that leads to the formation of ascites.

Thromboelastographic Evaluation of Dogs with Acute Liver Disease

BACKGROUND

Given the liver's pivotal role in hemostasis and fibrinolysis, the coagulopathy accompanying hepatic disease is complex.

HYPOTHESIS/OBJECTIVES

To prospectively evaluate kaolin-activated thromboelastography (TEG) in dogs with acute liver disease (ALD) and compare with plasma-based coagulation tests.

ANIMALS

Twenty-one dogs with a diagnosis of ALD based on recent onset of clinical signs accompanied by increases in serum bilirubin concentration and alanine aminotransferase activity.

METHODS

Clinical presentation, CBC, serum biochemistry, platelet count, prothrombin time (PT), activated partial thromboplastin time (aPTT), and TEG analysis were evaluated in 21 dogs with a subset also having fibrinogen, antithrombin (AT) activity, protein C (PC) activity, d-dimers, and von Willebrand's factor (vWF) activity analyzed. A PT >1.5 times the upper limit of normal defined acute liver failure (ALF).

RESULTS

Dogs with ALD had mean increases in R, K, LY30, PT, aPTT, and vWF activity, and decreases in angle, maximal amplitude (MA), G, AT activity, and PC activity. The TEG results defined dogs as hypocoagulable (11/21), normocoagulable (8/21), or hypercoagulable (2/21). Increases in LY30 defined 8/21 dogs as hyperfibrinolytic. Hypocoagulable and hyperfibrinolytic dogs had lower fibrinogen and PC activity than dogs without these abnormalities. Overall, ALF dogs had greater increases in K and LY30, and decreases in MA, G, and PC activity than dogs with less severe hepatic impairment. Results for MA and LY30 were positively correlated with serum bilirubin concentration and white blood cell count, and negatively correlated with serum cholesterol concentration.

CONCLUSIONS AND CLINICAL IMPORTANCE

ALD dogs have a range of coagulation abnormalities that trend toward hypocoagulability and hyperfibrinolysis as functional impairment occurs.