Effect of sampling time on urinary electrolytes following oral furosemide administration in dogs with myxomatous mitral valve disease

Introduction/ObjectivesUrine chemistry has received growing attention to estimate the diuretic response in dogs with cardiac disease.The aim of the study was to evaluate the impact of time elapsed between the oral furosemide administration and sample collection on urine chemistry in dogs with myxomatous mitral valve disease (MMVD) receiving diuretic therapy in American College of Veterinary Internal Medicine (ACVIM) stage C.Materials and methodsSeventy-three dogs with MMVD ACVIM stage C and 106 healthy dogs were prospectively included. Dogs with MMVD were divided, based on the time of sampling, in morning group (MMVD-MG) of one to 6 h and an evening group (MMVD-EG) over 6 h from oral furosemide administration. Analogously, healthy dogs sampled between 9 a.m. and 1 p.m. and between 2 and 7 p.m. were divided in a morning group (H-MG) and an evening group (H-EG), respectively. Urine chemistry, including fractional excretion of electrolytes, was evaluated and compared among groups.ResultsHigher excretion of sodium and chloride and higher urine sodium to urine potassium ratio (uNa⁺:uK⁺) were detected in MMVD-MG than MMVD-EG (P = 0.021, P = 0.038, and P = 0.016, respectively). Natriuresis, chloriuresis, and uNa⁺:uK+ were higher in MMVD-MG than H-MG, while no differences were found in the comparison between H-MG and H-EG and between MMVD-EG and H-EG.ConclusionsUrinary electrolyte excretion is significantly increased within 6 h from furosemide administration in MMVD ACVIM stage C dogs. Time of sampling from furosemide administration significantly affects urine chemistry in MMVD dogs and should be considered in clinical practice and the research field.     

Association between atrial fibrillation and right-sided manifestations of congestive heart failure in dogs with degenerative mitral valve disease or dilated cardiomyopathy

IntroductionTo determine whether dogs with atrial fibrillation (AF) are more likely to develop right-sided manifestations of congestive heart failure (R-CHF) than dogs without AF.AnimalsTwo hundred twenty dogs diagnosed with congestive heart failure (CHF) secondary to degenerative mitral valve disease (DMVD, n = 155) or dilated cardiomyopathy (DCM, n = 65) at a referral institution.MethodsMedical records were reviewed to extract relevant clinical and echocardiographic data.ResultsFifty dogs had AF at the time of CHF diagnosis, including 17/155 (11.0%) dogs with DMVD and 33/65 (50.8%) dogs with DCM. Sixty dogs had R-CHF evidenced by cavitary effusions. Among DMVD dogs, R-CHF occurred in 13/17 (76.5%) dogs with AF compared with 10/138 (7.2%) dogs without AF; among DCM dogs, R-CHF occurred in 24/33 (72.7%) dogs with AF compared with 13/32 (40.6%) dogs without AF. Dogs with AF were more likely to manifest R-CHF signs than dogs without AF (p < 0.0001 for DMVD; p = 0.0125 for DCM). The presence of AF, diagnosis of DCM, and moderate to severe tricuspid regurgitation were associated with R-CHF in multivariate analysis. AF was the strongest predictor of R-CHF (odds ratio, 14.44; 95% confidence interval, 5.75–36.26).ConclusionsDogs with AF are more likely to manifest R-CHF than dogs without AF. Cavitary effusions are an expected finding in approximately three-quarters of dogs with AF and CHF secondary to either DCM or DMVD.     

Prediction of first onset of congestive heart failure in dogs with degenerative mitral valve disease: The PREDICT cohort study

ObjectiveTo identify risk factors for first-onset congestive heart failure (CHF) in dogs with degenerative mitral valve disease (DMVD).AnimalsEighty-two dogs with and without CHF secondary to DMVD were retrospectively assigned to a derivation cohort. Sixty-five dogs with asymptomatic DMVD were recruited into a prospective validation cohort.MethodsVariables associated with risk of CHF in dogs were identified in a derivation cohort and used to construct a predictive model, which was then prospectively tested through longitudinal examination of a validation cohort.ResultsLogistic regression analysis of the derivation cohort yielded a predictive model that included the left atrial to aortic root dimension ratio (LA:Ao) and plasma concentration of N-terminal pro-B-type natriuretic peptide (NT-proBNP). When this model was prospectively applied to the validation cohort, it correctly predicted first-onset of CHF in 69.2% of cases. Analysis of the validation cohort revealed that plasma NT-proBNP concentration and indexed left ventricular end-diastolic diameter (LVIDd:Ao) were independent risk factors for development of first-onset CHF in dogs with DMVD (NT-proBNP ≥1500 pmol/L, odds ratio (OR), 5.76, 95% confidence interval (CI), 1.37–24.28, P = 0.017; LVIDd:Ao ≥3, OR, 6.11, 95% CI, 1.09–34.05, P = 0.039).ConclusionsMeasures of left heart size and plasma NT-proBNP concentration independently estimate risk of first-onset of CHF in dogs with DMVD. These parameters can contribute to the management of dogs with DMVD.     

Total bilirubin is an independent predictor of death in dogs with degenerative valvular disease and dilated cardiomyopathy

IntroductionThere is little published regarding the association between canine cardiovascular disease and the hepatic system. The objective of the study was to evaluate the relationship between hepatic parameters, survival, and disease stages of dogs with either dilated cardiomyopathy (DCM) or degenerative valvular disease (DVD).Animals, materials, and methodsRetrospective study analyzing hepatic parameters in dogs with DVD or DCM in American College of Veterinary Internal Medicine stage B or C and healthy control dogs. Associations between liver parameters, type and stage of disease, and survival were investigated.ResultsNinety-nine dogs were included in the study: 61 DVD, 22 DCM, and 16 controls. Differences in liver parameter concentrations between DCM, DVD, and disease stages were found. Univariate analysis identified alanine aminotransferase (P < 0.001), aspartate aminotransferase (P = 0.02), and total bilirubin (P = 0.005) as predictors of mortality. In the multivariate analysis, total bilirubin remained an independent predictor of mortality.ConclusionsThe observed differences between DCM, DVD, and disease stages are likely consistent with disease-specific hemodynamics and progression of disease. This and the role of total bilirubin as an independent predictor for mortality indicate that in dogs with DVD and DCM the cardiovascular–hepatic interaction might be of relevance for disease progression and outcome, as reported for humans with cardiac disease. Further studies into the role of hepatic function in canine cardiac disease are required.     

The outcome of surgical mitral valve repair with loop-in-loop technique in dogs with different stage myxomatous mitral valve disease

ObjectivesSurgical mitral valve repair is a possible option for dogs with myxomatous mitral valve disease. However, information on surgical results and postoperative echocardiography is limited. This study aimed to verify the stage-specific surgical results of mitral valve repair and postoperative echocardiographic changes for two years following surgery.AnimalsAdult dogs (n = 55) treated with surgical mitral valve repair using the loop-in-loop technique were included in this study. Medical records were retrospectively reviewed.ResultsNinety percent of cases (50/55) survived to discharge, which survival was significantly decreased in myxomatous mitral valve disease advanced-stage dogs, Stage B2 (n = 14): 100%, Stage C (n = 27): 96.2%, and Stage D (n = 14): 71.4%. Significant reductions of overall heart size (vertebral heart score: preoperative 11.4 vs. post one month 10.2, P < 0.001), left atrium (left atrium to aortic root ratio: preoperative 2.3 vs. post one month 1.5, P < 0.001) and left ventricle (left ventricular end-diastolic diameter [normalized for bodyweight]: preoperative 2.2 vs. post one month 1.5, P < 0.001) were documented one month after surgery, showing successful management of mitral regurgitation. All medications for mitral valve disease were discontinued three months after surgery. The recurrence of mitral regurgitation was not evident during the two-year follow-up period.ConclusionsSurgical mitral valve repair with the loop-in-loop technique is associated with significant decreases in indices of cardiac size at one-month post-repair. Disease stage influences operative survival after surgical mitral valve repair.     

Incremental predictive value of echocardiographic indices of right ventricular function in the assessment of long-term prognosis in dogs with myxomatous mitral valve disease

IntroductionFew studies have evaluated the utility of echocardiographic indices of right ventricular (RV) function in predicting prognosis in dogs with myxomatous mitral valve disease (MMVD).AnimalsSixty-seven client-owned dogs were diagnosed with MMVD.Materials and methodsclinical cohort study. Dogs diagnosed with American college of veterinary internal medicine (ACVIM) stage B2, C or D between April 2014 and March 2017 were enrolled. Long-term outcomes were assessed by telephone or from the medical record. The primary end-point was defined as cardiac-related death. Echocardiographic indices of RV function, including the RV Tei index, free wall and septal RV longitudinal strain, were obtained. Univariable and multivariable Cox proportional hazard analyses were used to identify variables predictive of cardiac-related death.ResultsTwenty-four dogs died during the follow-up period. The median follow-up time was 482 days, and the median survival time for dogs with cardiac-related death was 230 days. For cardiac-related death, peak early diastolic mitral inflow velocity, ACVIM stage C or D, tricuspid regurgitation velocity, RV Tei index and RV end-diastolic area were predictors in univariable Cox proportional hazard analysis. In multivariable Cox proportional analysis adjusted for the left atrial to aorta ratio, peak early diastolic mitral inflow velocity and ACVIM stage, an increase in the Tei index by 0.1 increased the hazard ratio of cardiac-related death by 33% (95% confidence interval, 16–70%; P = 0.002).ConclusionsIn dogs with MMVD, RV dysfunction assessed by the Tei index is an independent predictor of cardiac-related death.     

Polymorphism,coupling interval and prematurity index in dogs with degenerative mitral valve disease and ventricular arrhythmias

Ventricular arrhythmias (VA) are a recognized concern in dogs with degenerative mitral valve disease (DMVD). The coupling interval (CI) and the prematurity index (PI) have been shown to accurately differentiate between benign and malignant VA in people, where ventricular arrhythmias are known to be associated with an increased risk of development of signs of heart failure or sudden death. In this study, we characterized ventricular arrhythmias in dogs with symptomatic and asymptomatic DMVD. Seventy dogs with naturally-occurring DMVD and ventricular arrhythmias were retrospectively studied. A cross-sectional investigation including dogs with either symptomatic (stages C/D; n?=?41) or asymptomatic (stages B1/B2; n?=?29) DMVD was performed. Electrocardiographic tracings were reviewed to calculate both the CI and PI. In eight dogs these indices were compared with those obtained from both a Holter recording and a standard ECG tracing and no statistical differences were found (CI, p?=?0.97; PI, p?=?0.17). Even though CI and PI were determined in all animals enrolled in the study, VPC characteristics were only compared between symptomatic and asymptomatic dogs when a 24-h Holter recording was available (n?=?49). The PI was different (p?=?0.01) between symptomatic (0.65?±?0.17) and asymptomatic (0.56?±?0.18) dogs, but CI was considered similar (p?=?0.91). Also, the symptomatic dogs had more polymorphic VPC (p?=?0.002) and supraventricular arrhythmias (p?=?0.0002) than the asymptomatic animals. Polymorphism, and repeating patterns of ventricular premature complexes, were characteristics frequently present in overtly symptomatic animals affected by mitral endocardiosis.     

Noninvasive electrocardiographic parameters to assess interventricular dyssynchrony in dogs with bundle branch blocks

ObjectivesTo define electrocardiographic features of complete left bundle branch block (LBBB) and right bundle branch block (RBBB), and the use of R-peak time (RPT) to identify interventricular dyssynchrony in dogs with BBB.Animals, materials and methodsTwelve-lead ECG tracings of 20 dogs with RBBB, 20 with LBBB, and 60 healthy dogs were retrospectively analyzed and RPT was measured in precordial leads. Interventricular dyssynchrony index (IDI) was than calculated.ResultsIn RBBB, mean electrical axis (MEA) was −111° [−120/−100°], V₁RPT was significantly longer (61 ms [55–72 ms]) than left precordial leads RPT (V₂:25 ms [22–30 ms]; V₃:25 ms [22–29 ms]; V₄:24 ms [21–29 ms]; V₅:25 ms [22–29 ms]; V₆:25 ms [22–29 ms]) and when compared to normal dogs (P < 0.001). In LBBB, MEA was 76° [70/81°], RPT in left precordial leads was significantly longer (V₂:49 ms [34–58 ms]; V₃:49 ms [43–57 ms]; V₄:52 ms [45–62 ms]; V₅:53 ms [45–63 ms]; V₆:55 ms [45–63 ms]) than V₁RPT (17 ms [15–20 ms]) and when compared to normal dogs (P < 0.001). V₁RPT > 28 ms and V₅RPT > 36 ms were found to predict the presence of RBBB and LBBB with a sensitivity of 100% and 96.7%, and a specificity of 96.7% and 99.5%, respectively. The IDI was 23% [16–29%] in normal dogs and significantly greater in dogs with RBBB (33% [30–38%]; P < 0.001) and LBBB (32% [23–41%]; P = 0.006).ConclusionsThis study defines ECG features and RPT in dogs with BBB. Electrical interventricular dyssynchrony can be defined using IDI in dogs with BBB.     

Association of diet with clinical outcomes in dogs with dilated cardiomyopathy and congestive heart failure

IntroductionDilated cardiomyopathy (DCM) in dogs has been associated with feeding of grain-free (GF), legume-rich diets. Some dogs with presumed diet-associated DCM have shown improved myocardial function and clinical outcomes following a change in diet and standard medical therapy.HypothesisPrior GF (pGF) diet influences reverse cardiac remodeling and clinical outcomes in dogs with DCM and congestive heart failure (CHF).Animals and methodsA retrospective study was performed with 67 dogs with DCM and CHF for which diet history was known. Dogs were grouped by diet into pGF and grain-inclusive (GI) groups. Dogs in the pGF group were included if diet change was a component of therapy. Survival was analyzed using Kaplan–Meier curves and the Cox proportional-hazards model.ResultsThe median survival time was 344 days for pGF dogs vs. 253 days for GI dogs (P = 0.074). Statistically significant differences in median survival were identified when the analysis was limited to dogs surviving longer than one week (P = 0.033). Prior GF dogs had a significantly worse outcome the longer a GF diet was fed prior to diagnosis (P = 0.004) or if they were diagnosed at a younger age (P = 0.017). Prior GF dogs showed significantly greater improvement in normalized left ventricular internal diastolic diameter (P = 0.038) and E-point septal separation (P = 0.031) measurements and significant decreases in their furosemide (P = 0.009) and pimobendan (P < 0.005) dosages over time compared to GI dogs.ConclusionsPrior GF dogs that survived at least one week after diagnosis of DCM, treatment of CHF, and diet change had better clinical outcomes and showed reverse ventricular remodeling compared to GI dogs.     

Clinical assessment of systolic myocardial deformations in dogs with chronic mitral valve insufficiency using two-dimensional speckle-tracking echocardiography

ObjectiveThe objective of this study was to clinically assess myocardial deformations in dogs with chronic mitral valve insufficiency (CMVI) using two-dimensional speckle-tracking echocardiography (2D-STE).Animals87 dogs with CMVI.MethodsDogs were placed into 1 of 3 classes, based on the International Small Animal Cardiac Health Council classification. In addition, 20 weight- and age-matched healthy dogs were enrolled as controls. The dogs were examined for myocardial deformations using 2D-STE, and strain and strain rate in the longitudinal, circumferential, and radial directions were evaluated.ResultsClass II and III dogs had higher circumferential strain than class I dogs (P = 0.002 and P = 0.001, respectively) and controls (P < 0.001 and P < 0.001, respectively). Class III dogs had higher radial strain than class I dogs (P = 0.001) and controls (P < 0.001). Class III dogs had higher radial strain rate than class I dogs (P = 0.006) and controls (P = 0.001). Other deformations, including longitudinal deformations, were not significantly different between classes of CMVI or between CMVI dogs and controls.ConclusionsIn the clinical progression of CMVI in dogs, myocardial deformations, as assessed by 2D-STE, differed according to myocardial contractile direction. Thus, assessments of multidirectional myocardial deformations may be important for better assessment of clinical cardiac function in dogs with CMVI.     

Effect of age on myocardial function assessed by two-dimensional speckle-tracking echocardiography in healthy beagle dogs

ObjectivesThe objective of this study was to evaluate the effect of age on myocardial function assessed by two-dimensional speckle-tracking echocardiography (2D-STE) in healthy dogs.AnimalsThirty-two healthy Beagles were used.MethodsMyocardial function was assessed in each dog by using 2D-STE, and the results were compared between young and old dogs.ResultsThe myocardial deformations in systole, besides the apical rotation rate, were not significantly different between young and old dogs. In contrast, the early diastolic circumferential strain rate, basal rotation rate, and torsion rate were significantly lower in old dogs than in young dogs (P = 0.03, P = 0.033, and P = 0.015, respectively). Late diastolic longitudinal and radial strain rates were significantly higher in old dogs than in young dogs (P = 0.002 and P = 0.018, respectively).ConclusionsYoung and old dogs showed similar systolic myocardial deformations, but significant differences in the values of some diastolic deformation variables were found between young and old dogs, highlighting the need for using age-matched control subjects in studies of diastolic function.     

Prevalence of and Risk Factors for Degenerative Mitral Valve Disease in Dogs Attending Primary‐care Veterinary Practices in England

Background

To date, epidemiological studies on degenerative mitral valve disease (DMVD) in dogs have largely reported referral caseloads or been limited to predisposed breeds. Analysis of primary‐care data to identify factors associated with DMVD would help clinicians identify high‐risk individuals and improve understanding.

Objectives

To estimate the prevalence of and identify risk factors for DMVD in dogs attending primary‐care veterinary practices in England.

Animals

Cases were identified within the electronic patient records of 111,967 dogs attending 93 practices. Four hundred and 5 dogs were diagnosed with DMVD (diagnosed cases) and a further 3,557 dogs had a heart murmur (HM) consistent with DMVD (possible cases).

Methods

Retrospective cross‐sectional study design. Prevalence was adjusted for the sampling approach. Mixed effects logistic regression models identified factors associated with DMVD.

Results

Prevalence estimates of diagnosed DMVD and HMs consistent with DMVD (both diagnosed and possible cases) were 0.36% (95% confidence interval [CI]: 0.29–0.45) and 3.54% (95% CI: 3.26–3.84) respectively. In the multivariable analysis, males had higher odds of diagnosed DMVD than did females (odds ratio [OR] 1.40, 95% CI: 1.12–1.74). Insured dogs had increased odds of DMVD compared with noninsured dogs (OR 3.56, 95% CI: 2.79–4.55) and dogs ≥20 kg had approximately half the odds of DMVD diagnosis compared with dogs <20 kg (OR 0.51, 95% CI: 0.36–0.74). Strong associations between a DMVD diagnosis and individual breeds and age were identified.

Conclusions and Clinical Importance

Degenerative mitral valve disease was a common disorder in practice‐attending dogs. Knowledge of identified risk factors for DMVD could improve clinical diagnosis and direct future research.     

Retrospective review of carvedilol administration in 38 dogs with preclinical chronic valvular heart disease

ObjectivesReport the effect of carvedilol administration on clinical and echocardiographic parameters and outcome in dogs with preclinical (ACVIM Stage B) chronic valvular heart disease (CVD).Animals, materials and methodsRetrospective case series of 38 client-owned dogs.Demographic, physical examination and diagnostic imaging findings, blood pressure (BP), administration details and outcome were obtained from medical records of dogs receiving carvedilol for preclinical CVD. When possible, additional follow-up information was obtained through telephone interviews with referring veterinarians and owners.ResultsBaseline data and follow-up were evaluated. Median and interquartile range (IQR) for age and weight were 8.6 (7.2–10.8) years and 8.5 (7.6–9.6) kg. 14/38 were male; 33/38 were Cavalier King Charles Spaniels; 33/38 had Stage B2 CVD. The initial dose of carvedilol was 0.31 (0.26–0.35) mg/kg PO twice daily. The carvedilol dose achieved following up titration was 1.11 (0.81–1.32) mg/kg twice daily. No adverse effects were recorded during up titration. Median survival for all dogs was 48.5 months with a 95% CI of 38.3–58.6.ConclusionsThis study suggests that carvedilol at the dose reported herein is well tolerated in small breed dogs with preclinical CVD. Prospective studies to evaluate efficacy are warranted.     

Anatomic regurgitant orifice area obtained using 3D-echocardiography as an indicator of severity of mitral regurgitation in dogs with myxomatous mitral valve disease

Objectives

To determine feasibility and repeatability of measuring the anatomic regurgitant orifice area (AROA) using real-time three-dimensional transthoracic echocardiography (RT3DE) in dogs with myxomatous mitral valve disease (MMVD), and to investigate differences in the AROA of dogs with different disease severity and in different American College of Veterinary Internal Medicine (ACVIM) stages.

Volumetric evaluation of fluid responsiveness using a modified passive leg raise maneuver during experimental induction and correction of hypovolemia in anesthetized dogs

ObjectiveTo demonstrate if modified passive leg raise (PLR_M) maneuver can be used for volumetric evaluation of fluid responsiveness (FR) by inducing cardiac output (CO) changes during experimental induction and correction of hypovolemia in healthy anesthetized dogs. The effects of PLR_M on plethysmographic variability index (PVI) and pulse pressure variation (PPV) were also investigated.Study designProspective, crossover study.AnimalsA total of six healthy anesthetized Beagle dogs.MethodsDogs were anesthetized with propofol and isoflurane. They were mechanically ventilated under neuromuscular blockade, and normothermia was maintained. After instrumentation, all dogs were subjected to four stages: 1, baseline; 2, removal of 27 mL kg^–1 circulating blood volume; 3, after blood re-transfusion; and 4, after 20 mL kg^–1 hetastarch infusion over 20 minutes. A 10 minute stabilization period was allowed after induction of each stage and before data collection. At each stage, CO via pulmonary artery thermodilution, PVI, PPV and cardiopulmonary variables were measured before, during and after the PLR_M maneuver. Stages were sequential, not randomized. Statistical analysis included repeated measures anova and Tukey’s post hoc test, considering p < 0.05 as significant.ResultsDuring stage 2, PLR_M at a 30° angle significantly increased CO (mean ± standard deviation, 1.0 ± 0.1 to 1.3 ± 0.1 L minute^–1; p < 0.001), with a simultaneous significant reduction in PVI (38 ± 4% to 21 ± 4%; p < 0.001) and PPV (27 ± 2% to 18 ± 2%; p < 0.001). The PLR_M did not affect CO, PPV and PVI during stages 1, 3 and 4.Conclusions and clinical relevanceIn anesthetized dogs, PLR_M at a 30° angle successfully detected FR during hypovolemia, and identified fluid nonresponsiveness during normovolemia and hypervolemia. Also, in hypovolemic dogs, significant decreases in PVI and PPV occurred in response to PLR_M maneuver.     

Ultrasonographic measurement of flow-mediated vasodilation in dogs with chronic valvular disease

ObjectivesTo measure flow-mediated vasodilation (FMD) in healthy dogs and in client-owned dogs with chronic valvular disease (CVD) and to investigate possible correlations between markers of CVD severity and FMD.AnimalsTwelve dogs with CVD and 11 healthy weight-matched dogs.MethodsBrachial artery FMD following 5 min inflation of a cuff around the antebrachium was measured in 12 dogs with CVD and 11 healthy weight-matched dogs. Measurements were also obtained in the healthy dogs 5 min after cuff placement but without inflation (‘sham cuff placement’). Dogs with CVD underwent echocardiography to confirm and characterize their disease.ResultsIn healthy dogs (median age 4 [2–6] years), median FMD was 7.7% versus 3.4% with sham cuff placement (P = 0.003). In dogs with CVD (median age 8 [4–16] years) median FMD was 5.5% versus 7.7% in healthy dogs (P = 0.131). FMD showed an inverse correlation with left ventricular end-diastolic diameter normalized for body weight (r = ?0.76, P = 0.0043).ConclusionsBrachial FMD in dogs with early CVD inversely correlates with severity of left ventricular remodelling.     

Effects of vatinoxan in dogs premedicated with medetomidine and butorphanol followed by sevoflurane anaesthesia: a randomized clinical study

ObjectiveTo investigate effects of vatinoxan in dogs, when administered as intravenous (IV) premedication with medetomidine and butorphanol before anaesthesia for surgical castration.Study designA randomized, controlled, blinded, clinical trial.AnimalsA total of 28 client-owned dogs.MethodsDogs were premedicated with medetomidine (0.125 mg m^?2) and butorphanol (0.2 mg kg^?1) (group MB; n = 14), or medetomidine (0.25 mg m^?2), butorphanol (0.2 mg kg^?1) and vatinoxan (5 mg m^?2) (group MB-VATI; n = 14). Anaesthesia was induced 15 minutes later with propofol and maintained with sevoflurane in oxygen (targeting 1.3%). Before surgical incision, lidocaine (2 mg kg^?1) was injected intratesticularly. At the end of the procedure, meloxicam (0.2 mg kg^?1) was administered IV. The level of sedation, the qualities of induction, intubation and recovery, and Glasgow Composite Pain Scale short form (GCPS-SF) were assessed. Heart rate (HR), respiratory rate (f_R), mean arterial pressure (MAP), end-tidal concentration of sevoflurane (Fe′Sevo) and carbon dioxide (Pe′CO₂) were recorded. Blood samples were collected at 10 and 30 minutes after premedication for plasma medetomidine and butorphanol concentrations.ResultsAt the beginning of surgery, HR was 61 ± 16 and 93 ± 23 beats minute^?1 (p = 0.001), and MAP was 78 ± 7 and 56 ± 7 mmHg (p = 0.001) in MB and MB-VATI groups, respectively. No differences were detected in f_R, Pe′CO₂, Fe′Sevo, the level of sedation, the qualities of induction, intubation and recovery, or in GCPS-SF. Plasma medetomidine concentrations were higher in group MB-VATI than in MB at 10 minutes (p = 0.002) and 30 minutes (p = 0.0001). Plasma butorphanol concentrations were not different between groups.Conclusions and clinical relevanceIn group MB, HR was significantly lower than in group MB-VATI. Hypotension detected in group MB-VATI during sevoflurane anaesthesia was clinically the most significant difference between groups.     

Renal resistive index in 55 dogs with degenerative mitral valve disease

Background

Azotemia occurs frequently in dogs with degenerative mitral valve disease (DMVD). It could indicate changes in renal hemodynamics.

Hypothesis/Objectives

To assess the renal resistive index (RI) in dogs with DMVD, and the statistical link between heart failure class, azotemia, echo‐Doppler parameters, several plasma variables, and RI.

Animals

Fifty‐five dogs with naturally occurring DVMD were used (ISACHC class 1 [n = 28], 2 [n = 19], and 3 [n = 8]).

Methods

Observational, blinded study, performed under standardized conditions. Physical examination, renal ultrasonography, and echo‐Doppler examinations were performed in awake dogs. The RI of the renal, interlobar, and arcuate arteries were measured. Plasma creatinine, urea, and N‐terminal pro‐B‐type natriuretic peptide concentrations (NT‐proBNP) were determined. Statistical links between variables and RI were tested by means of a general linear model.

Results

Although the RI of renal and arcuate arteries were unaffected by ISACHC class, the left interlobar RI increased (P < .001) from 0.62 ± 0.05 (mean ± SD) in class 1 to 0.76 ± 0.08 in class 3. It was also higher (P < .001) in azotemic (0.74 ± 0.08) than in non‐azotemic (0.62 ± 0.05) dogs. Similar findings were observed for right interlobar RI. Univariate analysis showed a positive statistical link between NT‐proBNP (P = .002), urea (P < .001), creatinine (P = .002), urea‐to‐creatinine ratio (P < .001), left atrium‐to‐aorta ratio (P < .001), regurgitation fraction (P < .001), systolic pulmonary arterial pressure (P < .001), shortening fraction (P = .035), and RI.

Conclusion and Clinical Importance

In dogs with DMVD, interlobar RI increases with heart failure severity and azotemia but a cause and effect relationship remains to be established.     

Entamoeba infections in different populations of dogs in an endemic area of Lahore,Pakistan

Entamoeba histolytica, a protozoan parasite that affects humans and other primates all over the world. It is a common waterborne pathogen in endemic areas that have fecal oral transmission cycle. The aim of the present study was to examine the prevalence of E. histolytica and other Entamoeba species cysts in three different dog populations. Fecal samples from 600 dogs were collected and processed to detect Entamoeba cysts using the triple fecal test (light microscopy) and fecal antigens of E. histolytica were detected using a fecal antigen ELISA (TechLab E. histolytica II). Because it is impossible to differentiate E. histolytica from Entamoeba dispar and E. moshkovskii, using light microscopy we referred to all cysts morphologically consistent with E. histolytica as E. histolytica/dispar/moskovskii to reflect this uncertainty. Samples from 197 household dogs without clinical signs, 122 samples from household dogs exhibiting clinical signs of diarrhea, dysentery and vomiting and 281 stray dogs with no specific clinical signs were examined. Entamoeba histolytica-like cysts were observed in 94 (15.6%, 95% CI = ±3.88) by triple fecal test microscopy and E. histolytica antigens were demonstrated in 66 (11%, 95% CI = ±4.41) by fecal antigen ELISA in 600 fecal samples. Significant differences (P ≤ 0.05) in prevalence were found between the three populations. Twenty (10.1%, 95% CI = ±7.86) and 11 (5.6%, 95% CI = ±7.70) of 197 fecal samples from household dogs without clinical signs were positive by microscopy and by antigen ELISA, respectively. Twenty-nine (23.8%, 95% CI = ±6.58) and 23 (18.8%, 95% CI = ±7.81) of 122 the fecal samples from household dogs with clinical signs were positive by microscopy and by antigen ELISA, respectively. Forty-five (16.01%, 95% CI = ±5.62) and 32 (11.3%, 95% CI = ±6.38) of 281 fecal samples from stray dogs were positive by microscopy and by fecal antigen ELISA, respectively. Dogs from the youngest age group (6 months to 1 year) were more likely to be E. histolytica antigen positive than were dogs from the other two older age groups, with a significant difference (P ≤ 0.05) between all age groups. Statistically, no significant (P ≥ 0.05) difference of prevalence was seen in male and female dogs. The local dogs had the highest prevalence rate of E. histolytica antigens (36 of 246, 14.2%, 95% CI = ±6.32) followed by imported breeds (11 of 115, 9.5%, 95% CI = ±10.4) and crossbred (19 of 239, 8.3%, 95% CI = ±7.47), indicating a significant (P ≤ 0.05) trend of positivity between various breeds of dogs. These findings suggest that dogs may play an important role in the epidemiology of this pathogen.