Usefulness of cardiac biomarker screening to detect dilated cardiomyopathy in Dobermanns.

OBJECTIVES: To assess the diagnostic accuracy of two cardiac biomarker assays (N-terminal pro-BNP , Troponin I) in detecting dilated cardiomyopathy in Dobermanns. MATERIALS AND METHODS: Dobermanns undergoing cardiac biomarker testing were screened by echocardiography and Holter monitoring, then assigned to a group: normal, equivocal, arrhythmia form of dilated cardiomyopathy, echocardiographic form of dilated cardiomyopathy or both. Some were reassessed to identify final status. Initial cardiac biomarker results were compared to final status. Receiver operating characteristic curves were used to identify area under the curve and corresponding sensitivity (Se), specificity (Sp) for different cut-offs (CO) for each cardiac biomarker. RESULTS: A total of 118 Dobermanns with cardiac biomarker data had echocardiography/Holter assessment. Repeat assessment was carried out in 47 Dobermanns after 394.5 ±151.0 days. Seventeen dogs changed group between initial and final status. The final status of 59 was normal, nine were equivocal and 50 had dilated cardiomyopathy (prevalence 42.4%). Of the dilated cardiomyopathy group, 25 had dilated cardiomyopathy-both, 13 dilated cardiomyopathy-echocardiography and 12 dilated cardiomyopathy-Holter. Receiver operating characteristic area under the curve=0.807 for N-terminal proBNP (Se 0.69 and Sp 0.81) and 0.873 for high-sensitivity cardiac Troponin I (Se 0.77 and Sp 0.86). When both Se and Sp were optimised for all forms of dilated cardiomyopathy, N-terminal proBNP cut-off was 626 pmol/L (Se and Sp 0.79) and high-sensitivity cardiac Troponin I cut-off was 0.056 ng/mL (Se and Sp 0.84). Receiver operating characteristic area under the curve was higher for dilated cardiomyopathy-echocardiography (NT-proBNP 0.883; high-sensitivity cardiac Troponin I 0.907) than dilated cardiomyopathy-Holter. CLINICAL SIGNIFICANCE: Cardiac biomarker screening may be useful to select Dobermanns which would benefit from further assessment by echocardiography and Holter.

Phenotypic description of cardiac findings in a population of Dogue de Bordeaux with an emphasis on atrial fibrillation.

The aim of this study was to describe the clinical phenotype of Dogue de Bordeaux (DdB) referred for cardiac investigation, with particular reference to the prevalence of atrial fibrillation and associated features. Review of canine medical records of two United Kingdom veterinary referral hospitals identified 64 DdB with available echocardiographic and electrocardiographic (ECG)/Holter data. Atrial fibrillation was documented in 25 (39%) dogs and supraventricular tachycardia was recorded in five (7.8%) dogs. In a subset of 34 dogs, excluding congenital heart disease (n=17), presence of a cardiac mass (n=7) and non-cardiac neoplasia (n=6), 19 (56%) dogs had atrial fibrillation, with a median heart rate of 200 beats per min (bpm) on presentation. Atrial fibrillation was inconsistently associated with cardiac chamber remodelling, but was frequently associated with systolic dysfunction (13/19, 68.4%) and right sided atrial or ventricular dilatation (14/19, 73.7%) in dogs with atrial fibrillation in this subset. No dogs in this subset had right sided atrial or ventricular dilatation in the absence of supraventricular arrhythmia or systolic dysfunction. The absence of structural heart disease in some dogs with supraventricular arrhythmias suggests that an underlying primary arrhythmic process might be responsible for initiating remodelling, although a primary cardiomyopathy cannot be ruled out.

Clinical findings and treatment outcomes for cats diagnosed with patent ductus arteriosus in the UK: a retrospective study of 19 cases (2004-2012).

Patent ductus arteriosus (PDA) is infrequently reported in cats and represents between 1-7.3 per cent of left to right shunting cardiac congenital anomalies. The objective of this study was to report the presenting complaints, clinical examination findings, diagnostic findings, treatment outcomes and survival times in cats diagnosed with a PDA in the UK. Medical records from three major UK referral centres were searched for cats that were diagnosed with PDA from January 2004 to December 2012. Data obtained for analysis included: signalment, clinical examination findings including murmur characteristics, diagnostic imaging findings, treatment outcomes and survival times. Nineteen cats were included in the analysis. The most common reason for referral was investigation of an incidentally detected heart murmur without clinical signs (13/19; 68 per cent). Pulmonary arterial hypertension (PAH) was diagnosed in seven (37 per cent) cats and those cats with PAH were significantly more likely to present with signs of disease (P=0.004). Median survival time in cats that were diagnosed with PDA and died due to cardiac causes was 898 days (interquartile range 459-1011 days). The median survival time of those cats that had an additional congenital anomaly was significantly shorter to those cats without a congenital anomaly (P=0.008).

Assessment of mitral regurgitation in dogs: comparison of results of echocardiography with magnetic resonance imaging.

OBJECTIVES: Echocardiography is used routinely to assess mitral regurgitation severity, but echocardiographic measures of mitral regurgitation in dogs have not been compared with other quantitative methods. The study aim was to compare echocardiographic measures of mitral regurgitation with cardiac magnetic resonance imaging-derived mitral regurgitant fraction in small-breed dogs. METHODS: Dogs with myxomatous mitral valve disease scheduled for magnetic resonance imaging assessment of neurological disease were recruited. Correlations were tested between cardiac magnetic resonance imaging-derived mitral regurgitant fraction and the following echocardiographic measures: vena contracta/aortic diameter, transmitral E-wave velocity, amplitude of mitral prolapse/aortic diameter, diastolic left ventricular diameter:aortic diameter, left atrium:aortic diameter, mitral regurgitation jet area ratio and regurgitant fraction calculated using the proximal isovelocity surface area method. RESULTS: Measurement of cardiac magnetic resonance imaging-derived mitral regurgitant fraction was attempted in 21 dogs. Twelve consecutive, complete studies were obtained and 10 dogs were included in the final analysis: vena contracta/aortic diameter (r = 0 · 89, p = 0 · 001) and E-wave velocity (r = 0 · 86, p = 0 · 001) had the strongest correlations with cardiac magnetic resonance imaging-derived mitral regurgitant fraction. E velocity had superior repeatability and could be measured in all dogs. The presence of multiple jets precluded vena contracta/aortic diameter measurement in one dog. CLINICAL SIGNIFICANCE: Measurement of cardiac magnetic resonance imaging-derived mitral regurgitant fraction is feasible but technically demanding. The echocardiographic measures that correlated most closely with cardiac magnetic resonance imaging-derived mitral regurgitant fraction were vena contracta/aortic diameter and E-wave velocity.

Association of tricuspid annular plane systolic excursion with survival time in Boxer dogs with ventricular arrhythmias.

BACKGROUND: Tricuspid annular plane systolic excursion (TAPSE) is a useful estimate of right ventricular function in humans. Reference intervals for dogs have been generated, but the value of measuring TAPSE in other diseases, or investigating the association between TAPSE and outcome, is unknown. HYPOTHESIS: TAPSE is lower in Boxer dogs with ≥50 VPCs/24 h on Holter than in dogs with fewer ventricular ectopics, and lower TAPSE is associated with a shorter survival time. ANIMALS: Fifty Boxer dogs that presented for investigation of syncope or suspected arrhythmogenic right ventricular cardiomyopathy (ARVC) at a veterinary teaching hospital (2004-2011). METHODS: Retrospective study. Clinical records, Holter, and echocardiographic data were reviewed. TAPSE was measured in a blinded manner on stored echocardiographic cine-loops using anatomic M-mode. Outcome information was obtained and death was classified as cardiac or noncardiac. Survival analysis was performed using Kaplan-Meier curves and Cox proportional hazards models. RESULTS: TAPSE was lower in Boxers with ≥50 VPCs/24 h (13.9 ± 4.04 mm) than Boxers with <50 VPCs/24 h (16.8 ± 3.21 mm; P < .001). TAPSE <15.1 mm was associated with shorter cardiac survival time in all dogs (P = .004) and also in dogs without left ventricular dysfunction (P = .035). When controlling for other variables, including ventricular tachycardia on Holter and left ventricular systolic dysfunction, multivariable analysis showed that TAPSE remained an independent predictor of time to cardiac death (HR >4.09, 95%CI 1.15-16.9, P < .029). CONCLUSIONS AND CLINICAL IMPORTANCE: TAPSE offers prognostic value for Boxer dogs, including those with apparently normal systolic function and ≥50 VPCs/24 h on Holter analysis.

Prognostic value of 24-hour ambulatory ECG (Holter) monitoring in Boxer dogs.

BACKGROUND: Boxer dogs are reported to be predisposed to arrhythmogenic right ventricular cardiomyopathy (ARVC), but the natural history has not been well characterized and inconsistent diagnostic criteria have been applied to identify affected dogs. Echocardiographic examination findings are unremarkable in many affected Boxer dogs, and in these dogs, 24-hour ambulatory ECG (Holter) monitoring often is used for diagnostic and prognostic purposes, despite limited information available relating Holter findings to outcome. HYPOTHESIS/OBJECTIVES: Boxers with complex ventricular arrhythmias at initial presentation will have shorter survival times. The objective was to investigate the prognostic value of Holter monitoring in Boxer dogs. ANIMALS: One hundred and twenty-two Boxer dogs seen at 3 university referral hospitals. METHODS: Retrospective study. Survival times were obtained for Boxer dogs evaluated by echocardiography and a 24-hour Holter ECG. Kaplan-Meier survival analysis was used to estimate the median survival time and Cox proportional hazards analysis was used to identify variables independently associated with cardiac mortality. RESULTS: Outcome data were obtained for 122/163 dogs meeting the inclusion criteria. Of the 70 dogs that had died, 45 were considered to have suffered cardiac-related deaths. Median survival was significantly longer in dogs with a left ventricular systolic diameter (LVIDs) ≤ 35 mm compared with those with LVIDs > 35 mm (P < .001). Multivariable analysis in dogs with LVIDs ≤ 35 mm showed that the presence of ventricular tachycardia, age >4.5 years, and male sex were independent predictors of cardiac mortality. CONCLUSIONS AND CLINICAL IMPORTANCE: Holter monitoring in Boxer dogs provides valuable prognostic information.

Comparison of histopathologic findings in duodenal and ileal endoscopic biopsies in dogs with chronic small intestinal enteropathies.

BACKGROUND: The current tendency when investigating dogs with chronic upper gastrointestinal signs is to perform endoscopy and biopsy only the duodenum. This approach could lead to overlooking important ileal lesions and affect the clinical management. OBJECTIVES: To compare concurrent duodenal and ileal endoscopic biopsies in dogs with chronic enteropathies and evaluate their correlation with clinicopathologic findings. ANIMALS: Thirty-eight dogs with chronic enteropathies. METHODS: Duodenal and ileal biopsies were retrospectively reviewed. Nine histologic variables, 5 structural (villous stunting, epithelial injury, crypt distension, lacteal dilatation, and mucosal fibrosis) and 4 inflammatory (intraepithelial lymphocytes, lamina propria lymphocytes and plasma cells, eosinophils, and neutrophils) were scored. Clinical severity scores and relevant clinicopathologic variables were evaluated. RESULTS: There was only slight agreement between duodenal and ileal histologic scores (κ = 0.003). There was slight agreement between the presence of any of the morphological and inflammatory variables, with the exception of mucosal fibrosis (κ = 0.44). Statistically significant correlation was found between clinical severity and duodenal crypt distension (P = .031), ileal lacteal dilatation (P = .038), and ileal mucosal lymphoplasmacytic inflammation (P = .035). A significant correlation was found between hypoalbuminemia and ileal lacteal dilatation (P = .033) and number of ileal intraepithelial lymphocytes (P = .019). A statistically significant correlation was found between hypocobalaminemia and number of ileal intraepithelial lymphocytes (P = .012). CONCLUSIONS AND CLINICAL IMPORTANCE: When investigating dogs with chronic upper gastrointestinal signs, the collection of concurrent duodenal and ileal endoscopic biopsies is recommended.