Classification of feline hypertrophic cardiomyopathy-associated gene variants according to the American College of Medical Genetics and Genomics guidelines.

Introduction: The correct labeling of a genetic variant as pathogenic is important as breeding decisions based on incorrect DNA tests can lead to the unwarranted exclusion of animals, potentially compromising the long-term health of a population. In human medicine, the American college of Medical Genetics (ACMG) guidelines provide a framework for variant classification. This study aims to apply these guidelines to six genetic variants associated with hypertrophic cardiomyopathy (HCM) in certain cat breeds and to propose a modified criterion for variant classification. Methods: Genetic samples were sourced from five cat breeds: Maine Coon, Sphynx, Ragdoll, Devon Rex, and British Short- and Longhair. Allele frequencies were determined, and in the subset with phenotypes available, odds ratios to determine the association with HCM were calculated. In silico evaluation followed with joint evidence and data from other publications assisting in the classification of each variant. Results: Two variants, MYBPC3:c.91G > C [A31P] and MYBPC3:c.2453C > T [R818W], were designated as pathogenic. One variant, MYH7:c.5647G > A [E1883K], was found likely pathogenic, while the remaining three were labeled as variants of unknown significance. Discussion: Routine genetic testing is advised solely for the MYBPC3:c.91G > C [A31P] in the Maine Coon and MYBPC3:c.2453C > T [R818W] in the Ragdoll breed. The human ACMG guidelines serve as a suitable foundational tool to ascertain which variants to include; however, refining them for application in veterinary medicine might be beneficial.

Comparison of artificial intelligence to the veterinary radiologist's diagnosis of canine cardiogenic pulmonary edema.

Application of artificial intelligence (AI) to improve clinical diagnosis is a burgeoning field in human and veterinary medicine. The objective of this prospective, diagnostic accuracy study was to determine the accuracy, sensitivity, and specificity of an AI-based software for diagnosing canine cardiogenic pulmonary edema from thoracic radiographs, using an American College of Veterinary Radiology-certified veterinary radiologist's interpretation as the reference standard. Five hundred consecutive canine thoracic radiographs made after-hours by a veterinary Emergency Department were retrieved. A total of 481 of 500 cases were technically analyzable. Based on the radiologist's assessment, 46 (10.4%) of these 481 dogs were diagnosed with cardiogenic pulmonary edema (CPE+). Of these cases, the AI software designated 42 of 46 as CPE+ and four of 46 as cardiogenic pulmonary edema negative (CPE-). Accuracy, sensitivity, and specificity of the AI-based software compared to radiologist diagnosis were 92.3%, 91.3%, and 92.4%, respectively (positive predictive value, 56%; negative predictive value, 99%). Findings supported using AI software screening for thoracic radiographs of dogs with suspected cardiogenic pulmonary edema to assist with short-term decision-making when a radiologist is unavailable.

Immunofluorescent Localization of Plakoglobin Is Altered in Endomyocardial Biopsy Samples from Dogs with Clinically Relevant Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC).

Diagnosing the early stages of canine Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) is complicated by day-to-day arrhythmia variability, and absence of reliable, transthoracic echocardiographic features. Definitive diagnosis requires histopathologic identification of transmural fibrofatty replacement of the right ventricle. Reduction of immunofluorescent signal for plakoglobin (PG) at the intercalated disc (ID) is reported in ARVC-affected humans and boxers. Our objective was to determine whether reduced immunofluorescent signal for PG in endomyocardial biopsy samples (EMBs) correspond with a histopathologic diagnosis of ARVC. Here, 49 dogs were evaluated: 43 with advanced cardiac disease and 6 non-clinical boxers with mild to moderate ventricular arrhythmia (VA) burden. EMBs were obtained from all dogs; samples were prepared with antibodies recognizing cadherin (PC) and PG and evaluated with confocal microscopy. Investigators were blinded to breed and clinical status. ARVC was histopathologically diagnosed in 8 out of 49 dogs. Of these, three out of eight had clinical signs consistent with ARVC (two boxers, one English bulldog) and reduced PG signal at ID; five out of eight were non-clinical boxers with moderate VA and no reduction in PG. A total of 41 out of 49 dogs were histopathologically diagnosed with non-ARVC cardiac disease; 1 out of 41 showed reduction of PG at ID, while 40 out of 41 had no PG reduction. These results suggest that EMB PG signal is reduced in dogs with advanced ARVC, but not in the occult phase of the disease. Additionally, presence of PG at ID supports a diagnosis of non-ARVC cardiac disease in dogs with clinical signs. These results may offer an additional test that helps differentiate advanced ARVC from other myocardial diseases.

ACVIM consensus statement guidelines for the classification, diagnosis, and management of cardiomyopathies in cats.

Cardiomyopathies are a heterogeneous group of myocardial disorders of mostly unknown etiology, and they occur commonly in cats. In some cats, they are well-tolerated and are associated with normal life expectancy, but in other cats they can result in congestive heart failure, arterial thromboembolism or sudden death. Cardiomyopathy classification in cats can be challenging, and in this consensus statement we outline a classification system based on cardiac structure and function (phenotype). We also introduce a staging system for cardiomyopathy that includes subdivision of cats with subclinical cardiomyopathy into those at low risk of life-threatening complications and those at higher risk. Based on the available literature, we offer recommendations for the approach to diagnosis and staging of cardiomyopathies, as well as for management at each stage.

Temporal changes in clinical and radiographic variables in dogs with preclinical myxomatous mitral valve disease: The EPIC study.

BACKGROUND: The Evaluation of pimobendan in dogs with cardiomegaly caused by preclinical myxomatous mitral valve disease (EPIC) study monitored dogs with myxomatous mitral valve disease (MMVD) as they developed congestive heart failure (CHF). OBJECTIVES: To describe the changes in clinical and radiographic variables occurring as dogs with MMVD and cardiomegaly develop CHF, compared to similar dogs that do not develop CHF. ANIMALS: One hundred and thirty-five, and 73 dogs that did or did not develop CHF, respectively. MATERIALS AND METHODS: The following variables were evaluated in 2 groups of dogs (dogs that did or did not develop CHF): Heart rate (HR), clinic respiratory rate (RR), home-measured resting respiratory rate (RRR), rectal temperature (RT), body weight (BW), and vertebral heart sum (VHS). Absolute value and rate of change of each variable were calculated for each day a dog was in study. Daily means were calculated and plotted against time. The onset of CHF or last visit before leaving the study were set as reference time points. RESULTS: The most extreme values and rate of change occurred in variables immediately before onset of CHF. Vertebral heart sum increased earliest. Heart rate, RR, and RRR also increased. Rectal temperature and BW decreased. Increases in RR and RRR were most extreme and occurred immediately before CHF. CONCLUSIONS AND CLINICAL IMPORTANCE: Dogs with MMVD and cardiomegaly experience increases in HR, RR, RRR, and VHS, and decreases in BW and RT as they develop CHF. The variables with highest absolute change and rate of change were RR and RRR. These findings reinforce the value of RR and RRR as indicators of impending or incipient CHF.

Long-term incidence and risk of noncardiovascular and all-cause mortality in apparently healthy cats and cats with preclinical hypertrophic cardiomyopathy.

BACKGROUND: Epidemiologic knowledge regarding noncardiovascular and all-cause mortality in apparently healthy cats (AH) and cats with preclinical hypertrophic cardiomyopathy (pHCM) is limited, hindering development of evidence-based healthcare guidelines. OBJECTIVES: To characterize/compare incidence rates, risk, and survival associated with noncardiovascular and all-cause mortality in AH and pHCM cats. ANIMALS: A total of 1730 client-owned cats (722 AH, 1008 pHCM) from 21 countries. METHODS: Retrospective, multicenter, longitudinal, cohort study. Long-term health data were extracted by medical record review and owner/referring veterinarian interviews. RESULTS: Noncardiovascular death occurred in 534 (30.9%) of 1730 cats observed up to 15.2 years. Proportion of noncardiovascular death did not differ significantly between cats that at study enrollment were AH or had pHCM (P = .48). Cancer, chronic kidney disease, and conditions characterized by chronic weight-loss-vomiting-diarrhea-anorexia were the most frequently recorded noncardiovascular causes of death. Incidence rates/risk of noncardiac death increased with age in AH and pHCM. All-cause death proportions were greater in pHCM than AH (65% versus 40%, respectively; P < .001) because of higher cardiovascular mortality in pHCM cats. Comparing AH with pHCM, median survival (study entry to noncardiovascular death) did not differ (AH, 9.8 years; pHCM, 8.6 years; P = .10), but all-cause survival was significantly shorter in pHCM (P = .0001). CONCLUSIONS AND CLINICAL IMPORTANCE: All-cause mortality was significantly greater in pHCM cats due to disease burden contributed by increased cardiovascular death superimposed upon noncardiovascular death.

Evaluation of serum 25-hydroxyvitamin D concentrations in a heterogeneous canine ICU population.

OBJECTIVE: To identify the prevalence of low serum 25-hydroxyvitamin D (25-OH-D) concentrations in critically ill dogs and determine whether vitamin D concentration measured at admission correlates with illness severity and patient outcome. DESIGN: Prospective observational study from December 2013 to July 2014. SETTING: Private referral teaching hospital ICU. ANIMALS: One hundred eleven critically ill dogs admitted to the ICU, and 28 apparently healthy control dogs. INTERVENTIONS: Measurement of 25-OH-D concentration and assessment of physiological parameters required to calculate illness severity scores. MEASUREMENTS AND MAIN RESULTS: Blood was sampled to measure serum 25-OH-D concentration, point-of-care laboratory data (packed cell volume, total plasma protein, venous blood gas, electrolytes, plasma lactate, and blood glucose concentration), platelet count, and serum albumin within 12 hours of admission. Primary disease etiologies were determined. Mentation score, Acute Patient Physiologic and Laboratory Evaluation (APPLE) fast score, length of ICU hospitalization, and survival to discharge were recorded. Low serum 25-OH-D concentrations were detected in 25% (28/111) of the ICU cohort; 25-OH-D concentrations (median; IQR) (89.2; 26.3 ng/mL [222; 140.0 nmol/L]) were significantly lower in hospitalized dogs compared with the healthy cohort (127.5; 44.5 ng/mL [318; 111.0 nmol/L]) (P < 0.0001). Serum 25-OH-D concentrations had a weak positive correlation with albumin (r = 0.34, P = 0.0003), but not with any other blood analyte evaluated. Serum concentration of 25-OH-D was also weakly correlated with APPLEfast score (r = 0.31, P = 0.001). 25-OH-D concentrations (median; IQR) were significantly higher in ICU dogs that survived to discharge (95.5; 55 ng/mL [238; 137 nmol/L]) compared with nonsurvivors (60.0; 54 ng/mL [149; 135 nmol/L]; P < 0.001). CONCLUSIONS: Low serum 25-OH-D was recorded in one-quarter of critically ill dogs, and was significantly lower in nonsurvivors in comparison to survivors. There was weak correlation between serum 25-OH-D and illness severity. Further studies are required to clarify relationships between vitamin D status and outcome.

Utility of admission lactate concentration, lactate variables, and shock index in outcome assessment in dogs diagnosed with shock.

OBJECTIVE: To determine whether admission venous plasma lactate concentration, calculated lactate variables, or shock index (SI) could discriminate hospital survivors from nonsurvivors in dogs admitted with shock. DESIGN: Prospective investigation performed over a 19-month period. SETTING: Large urban private teaching hospital. ANIMALS: Twenty-three dogs consecutively admitted to the ICU from January 2008 to July 2009 with initial peripheral venous plasma lactate concentration >2 mmol/L (18.0 mg/dL) and clinical and hemodynamic parameters consistent with shock. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Heart rate, systolic blood pressure, and venous plasma lactate concentrations were serially recorded at predefined time points and used to calculate SI (SI = heart rate/systolic blood pressure) and lactate variables, including lactime (time lactate > 2.0 mmol/L), lactate clearance ([lactateinitial - lactatedelayed ]/lactateinitial × 100), and LACAREA (area under the lactate concentration versus time curve). Primary outcome was survival to discharge. Overall survival rate was 61%. Admission venous plasma lactate concentration did not differ between groups (P = 0.2). Lactime was shorter in survivors versus nonsurvivors (P = 0.02). Lactate clearance at 1, 10, 16, 24, and 36 hours, and final lactate clearance were greater in survivors versus nonsurvivors (P < 0.05). LACAREA at time intervals 0-1, 1-4, 4-10, 10-16, 16-24, 24-30, and 30-36 hours was larger in nonsurvivors versus survivors (P < 0.05). Total LACAREA did not differ between groups (P = 0.09). Admission SI and time to normalize SI (SI < 0.9) were not different between survivors and nonsurvivors (P > 0.05). CONCLUSIONS: While admission venous plasma lactate concentration could not discriminate between hospital survivors and nonsurvivors, lactate variables showed clinical utility to predict outcome in dogs with shock. Further studies are needed to determine SI reference ranges and optimal SI cut-off values to improve its prognostic ability in sick dogs.

Plasma and tissue angiotensin-converting enzyme 2 activity and plasma equilibrium concentrations of angiotensin peptides in dogs with heart disease.

BACKGROUND: Angiotensin-converting enzyme 2 (ACE2) is a homologue of angiotensin-converting enzyme (ACE) and produces angiotensin peptides (APs), such as angiotensin 1-9 and 1-7 that are vasodilatory and natriuretic, and act to counterbalance angiotensin II. HYPOTHESIS: Evidence of ACE2 can be found in tissues and plasma of dogs. Equilibrium concentrations of renin angiotensin aldosterone system (RAAS) APs differ in dogs with heart disease compared to healthy dogs and recombinant human ACE2 (rhACE2) alters relative concentrations of APs. ANIMALS: Forty-nine dogs with and 34 dogs without heart disease. METHODS: Immunohistochemistry and assays for tissue and plasma ACE2 activity and equilibrium concentrations of plasma RAAS APs were performed. RESULTS: Immunolabeling for ACE2 was present in kidney and myocardial tissue. Median plasma ACE2 activity was significantly increased in dogs with congestive heart failure (CHF; 6.9 mU/mg; interquartile range [IQR], 5.1-12.1) as compared to control (2.2 mU/mg; IQR, 1.8-3.0; P = .0003). Plasma equilibrium analysis of RAAS APs identified significant increases in the median concentrations of beneficial APs, such as angiotensin 1-7, in dogs with CHF (486.7 pg/mL; IQR, 214.2-1168) as compared to those with preclinical disease (41.0 pg/mL; IQR, 27.4-45.1; P < .0001) or control (11.4 pg/mL; IQR, 7.1-25.3; P = .01). Incubation of plasma samples from dogs with CHF with rhACE2 increased beneficial APs, such as angiotensin 1-9 (preincubation, 10.3 pg/mL; IQR, 4.4-37.2; postincubation, 2431 pg/mL; IQR, 1355-3037; P = .02), while simultaneously decreasing maladaptive APs, such as angiotensin II (preincubation, 53.4 pg/mL; IQR, 28.6-226.4; postincubation, 2.4 pg/mL; IQR, 0.50-5.8; P = .02). CONCLUSIONS AND CLINICAL IMPORTANCE: Recognition of the ACE2 system expands the conventional view of the RAAS in the dog and represents an important potential therapeutic target.

ACVIM consensus guidelines for the diagnosis and treatment of myxomatous mitral valve disease in dogs.

This report, issued by the ACVIM Specialty of Cardiology consensus panel, revises guidelines for the diagnosis and treatment of myxomatous mitral valve disease (MMVD, also known as endocardiosis and degenerative or chronic valvular heart disease) in dogs, originally published in 2009. Updates were made to diagnostic, as well as medical, surgical, and dietary treatment recommendations. The strength of these recommendations was based on both the quantity and quality of available evidence supporting diagnostic and therapeutic decisions. Management of MMVD before the onset of clinical signs of heart failure has changed substantially compared with the 2009 guidelines, and new strategies to diagnose and treat advanced heart failure and pulmonary hypertension are reviewed.

Effect of Targeted Pulsed Electromagnetic Field Therapy on Canine Postoperative Hemilaminectomy: A Double-Blind, Randomized, Placebo-Controlled Clinical Trial.

Intervertebral disc disease is one of the leading causes of paralysis in dogs. Pulsed electromagnetic field (PEMF) therapy has been advocated for improving wound healing and pain reduction; however, robust clinical trials are lacking. The present prospective, double-blind, placebo-controlled trial evaluated targeted PEMF therapy administered to 53 client-owned dogs who underwent hemilaminectomy for naturally occurring disk extrusion intervertebral disc disease. The dogs were randomized to receive either targeted PEMF (n = 27) or placebo treatment (n = 28). Wound healing, evaluated by visual analog score and wound evaluation scale, was significantly improved at 6 wk postoperatively in the treatment compared with the control group (P = .010 and .023, respectively). Pain medications were administered less frequently in dogs receiving PEMF treatment during the 7 day postoperative period compared with the control treatment group (P = .010) with codeine administered 1.8 times more frequently in the control group. No untoward effects were recorded in either treatment group. More frequent evaluation of outcome measures with larger patient numbers, as well as histologic samples, may be useful in future studies. Dogs receiving PEMF therapy following postoperative hemilaminectomy demonstrated improved wound scores at 6 wk and reduced mean number of owner-administered pain medications compared with the control group therapy.

Comparison of closed root planing with versus without concurrent doxycycline hyclate or clindamycin hydrochloride gel application for the treatment of periodontal disease in dogs.

OBJECTIVE To compare improvements in values for periodontal disease indices in dogs following treatment with closed root planing (CRP) alone, CRP with concurrent 8.5% doxycycline hyclate gel application, and CRP with concurrent 2% clindamycin hydrochloride reverse-polymer hydrogel application. DESIGN Randomized, blinded, controlled clinical trial. ANIMALS 34 client-owned dogs with periodontal pockets measuring 3.5 to 5.5 mm deep. PROCEDURES Dogs were randomly assigned to receive 1 of 3 treatments: CRP alone (n = 10) or CRP plus 8.5% doxycycline hyclate (12) or 2% clindamycin hydrochloride (12) gel applied within the periodontal pockets. Indices of periodontal disease severity were recorded before and 12 weeks after treatment, and outcomes were compared among treatment groups. RESULTS Except for gingivitis index, no significant differences were identified among the 3 treatment groups in the amount of improvement observed in values for periodontal disease indices following treatment. A minor but clinically unimportant improvement in mean gingivitis index values was identified for dogs treated with CRP plus doxycycline gel, which differed significantly from improvements in the other 2 groups. Teeth that were initially more severely affected (pocket depths, 5.0 to 5.5 mm) had the greatest amount of improvement, whereas teeth with only mildly high initial pocket depths (3.5 to 4.0 mm) had less improvement. CONCLUSIONS AND CLINICAL RELEVANCE Overall, addition of doxycycline or clindamycin gel application to CRP for the treatment of periodontal disease in dogs yielded no clinically relevant benefit over CRP during the 12-week follow-up period.

International collaborative study to assess cardiovascular risk and evaluate long-term health in cats with preclinical hypertrophic cardiomyopathy and apparently healthy cats: The REVEAL Study.

BACKGROUND: Hypertrophic cardiomyopathy is the most prevalent heart disorder in cats and principal cause of cardiovascular morbidity and mortality. Yet, the impact of preclinical disease is unresolved. HYPOTHESIS/OBJECTIVES: Observational study to characterize cardiovascular morbidity and survival in cats with preclinical nonobstructive (HCM) and obstructive (HOCM) hypertrophic cardiomyopathy and in apparently healthy cats (AH). ANIMALS: One thousand seven hundred and thirty client-owned cats (430 preclinical HCM; 578 preclinical HOCM; 722 AH). METHODS: Retrospective multicenter, longitudinal, cohort study. Cats from 21 countries were followed through medical record review and owner or referring veterinarian interviews. Data were analyzed to compare long-term outcomes, incidence, and risk for congestive heart failure (CHF), arterial thromboembolism (ATE), and cardiovascular death. RESULTS: During the study period, CHF, ATE, or both occurred in 30.5% and cardiovascular death in 27.9% of 1008 HCM/HOCM cats. Risk assessed at 1, 5, and 10 years after study entry was 7.0%/3.5%, 19.9%/9.7%, and 23.9%/11.3% for CHF/ATE, and 6.7%, 22.8%, and 28.3% for cardiovascular death, respectively. There were no statistically significant differences between HOCM compared with HCM for cardiovascular morbidity or mortality, time from diagnosis to development of morbidity, or cardiovascular survival. Cats that developed cardiovascular morbidity had short survival (mean ± standard deviation, 1.3 ± 1.7 years). Overall, prolonged longevity was recorded in a minority of preclinical HCM/HOCM cats with 10% reaching 9-15 years. CONCLUSIONS AND CLINICAL IMPORTANCE: Preclinical HCM/HOCM is a global health problem of cats that carries substantial risk for CHF, ATE, and cardiovascular death. This finding underscores the need to identify therapies and monitoring strategies that decrease morbidity and mortality.

An in vitro comparison of the effects of voluven (6% hydroxyethyl starch 130/0.4) and hespan (6% hydroxyethyl starch 670/0.75) on measures of blood coagulation in canine blood.

OBJECTIVE: To assess primary and secondary hemostasis following in vitro dilution of canine whole blood (WB) with hydroxyethyl starch (HES) 130/0.4 and HES 670/0.75. DESIGN: In vitro experimental study. SETTING: Private practice, teaching hospital. ANIMALS: Twenty-five healthy dogs. INTERVENTIONS: Each dog underwent venipuncture and 18 mL of venous blood was sampled once. MEASUREMENTS AND MAIN RESULTS: Collected blood was separated in 4 aliquots. Aliquot A served as baseline sample. The remaining tubes of WB were diluted with 0.9% saline, HES 670/0.75 and HES 130/0.4 at a ratio of 1:5.5. Dilutional effects were evaluated using prothrombin time (PT), activated partial thromboplastin time (aPTT), packed cell volume (PCV), thromboelastography (TEG), and platelet closure time (Ct), which was measured using a platelet function analyzer (PFA). Clot strength (ie, G value) was calculated from measured TEG values. Significant increases in PT (P < 0.05) and aPTT (P < 0.05) were documented following WB dilution with saline. Dilution of WB with HES 670/0.75 and HES 130/0.4 resulted in significant hypocoagulable changes in K, MA and G (P < 0.05) compared to baseline and saline. When comparing saline to HES 670/0.75, both R and K values were significantly increased (P < 0.05). K value was significantly increased (P < 0.05) when comparing baseline to HES 130/0.4 and HES 670/0.75. Ct (P < 0.05) was significantly prolonged after WB dilution with HES solutions but not after saline. CONCLUSIONS: Dilution of WB with HES 670/0.75 and HES 130/0.4 resulted in changes in primary and secondary hemostasis. Although there were small differences between saline and HES 670/0.75, no differences between HES solutions were evident in this small study. This may suggest there would be minimal increases in bleeding risk when either solution is administered to dogs at low doses. Clinical relevance of our findings requires further investigation.

Survey of referring veterinarians' perceptions of and reasons for referring patients to rehabilitation facilities.

OBJECTIVE To identify patterns of referral to US small animal rehabilitation facilities, document referring veterinarians' perceptions of rehabilitation services, and examine factors that encouraged and impeded referral of veterinary patients to rehabilitation facilities. DESIGN Cross-sectional survey. SAMPLE 461 completed surveys. PROCEDURES Referral lists were obtained from 9 US rehabilitation facilities, and surveys were emailed or mailed to 2, 738 veterinarians whose names appeared on those lists. Data obtained from respondents were used to generate descriptive statistics and perform χ(2) tests to determine patterns for referral of patients to rehabilitation facilities. RESULTS 461 surveys were completed and returned, resulting in a response rate of 16.8%. The margin of error was < 5% for all responses. Most respondents (324/461 [70.3%]) had referred patients for postoperative rehabilitation therapy. Respondents ranked neurologic disorder as the condition they would most likely consider for referral for future rehabilitation therapy. The most frequently cited reason for not referring a patient for rehabilitation therapy was perceived cost (251/461 [54.4%]) followed by distance to a rehabilitation facility (135/461 [29.3%]). Specialists were more likely than general practitioners to refer patients for rehabilitation therapy. The majority (403/461 [87.4%]) of respondents felt that continuing education in the field of veterinary rehabilitation was lacking. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated a need for continuing education in small animal rehabilitation for veterinarians. Improved knowledge of rehabilitation therapy will enable veterinarians to better understand and more specifically communicate indications and benefits for pets receiving this treatment modality.

Evaluation of the relationship between clinical variables and thromboelastographic findings in dogs with protein-losing nephropathy.

OBJECTIVE: To determine whether hypercoagulability in proteinuric dogs, defined by thromboelastography (TEG), is related to the degree of proteinuria, presence of systemic arterial hypertension, presence of hypoalbuminemia, or reduced antithrombin activity. DESIGN: Prospective study of client-owned dogs. Data collected from each patient included signalment, body weight, urine protein-to-creatinine ratio (UPC), serum albumin concentration, TEG values, noninvasive arterial blood pressure, and AT activity. Hypercoagulability was diagnosed by TEG and odds ratios for other measurements were assessed by univariate logistic regression. SETTING: Urban referral center and teaching hospital. ANIMALS: Seventy-six dogs with protein-losing nephropathy (PLN) based on UPC, diagnosed between Oct 2009 and Oct 2012. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The prevalence of hypercoagulability was 89%. No statistically significant associations were detected between hypercoagulability and UPC, serum albumin, noninvasive blood pressure, or AT activity (all P > 0.05). The prevalence of thromboembolism was 6.6%. CONCLUSIONS: Hypercoagulability was prevalent in dogs with PLN but could not be predicted based upon the presence or degree of proteinuria, systemic arterial hypertension, hypoalbuminemia, or low AT activity. The prevalance of thromboembolism was low in this population with PLN.

Management of asymptomatic (occult) feline cardiomyopathy: Challenges and realities.

BACKGROUND: Cardiomyopathy distinguishes a heterogeneous group of myocardial disorders that represent the most prevalent cause of feline heart disease. Etiology is uncertain and the natural history is presently unresolved. Hypertrophic cardiomyopathy is the most common of these conditions, and while the majority of affected cats are asymptomatic, a proportion is at risk to develop serious morbidities--the most devastating of which include congestive heart failure, arterial thromboembolism, and cardiac death. Predicting when or whether an asymptomatic cat might develop morbidity is hindered by lack of evidence-based clinical trials. Superimposed, these issues create an irresolvable predicament that presently confounds medical decision-making. METHODS: Review of current perspectives for managing asymptomatic (occult) feline cardiomyopathy. RESULTS: Complex pathophysiology and (likely) sarcomeric mutations give rise to heterogeneous cardiac phenotypes and variable clinical findings. Echocardiography remains the gold standard to clarify cardiac morphology. Frequently, however, detection of echocardiographic alterations--though often of unproven clinical significance--extrapolates by inference or implication a specter of disease, and with this, leads to a path of long-term treatment and testing. Presently, there is no proof that any particular therapy reduces morbidity or prolongs survival of cats affected with occult cardiomyopathy. Recently, however, evidence has accumulated to support the belief that certain prognostic indicators suggest risk for poor outcome. Accordingly, and in absence of evidence-based clinical trials, current practice has shifted to view therapy with the intent to target pathophysiology underlying documented or perceived clinical markers, whose presence portends high risk in certain patients. Affected animals and potentially siblings should be monitored using clinical testing that also takes into account age-related comorbidities. CONCLUSIONS: Asymptomatic (occult) feline cardiomyopathy includes complex and heterogeneous diseases whose outcomes are challenging to predict. Review of available evidence-based treatment data leaves no uncertainties regarding drugs with established efficacy. There presently are none. Current management focuses upon identification of documented risk factors, individualized and tailored therapy, and cogent monitoring. Drugs most commonly considered in this paradigm include those that might reduce thromboembolic risk in cases with substantial left atrial enlargement or dysfunction, agents to counteract left ventricular remodeling, or medications that ameliorate systolic or diastolic dysfunction. Discovering reliable prognostic indicators may further improve stratification to identify patients at highest risk, or detect subsets that respond favorably. These issues shape the challenge to identify sensible preventative management and cost-effective, long-term monitoring strategies.