The longitudinal outcome of canine (K9) myxomatous mitral valve disease (LOOK-Mitral) registry: Baseline treatment characteristics.

OBJECTIVES: To describe the medical treatment prescribed or modified by veterinary cardiologists at the enrollment visit in dogs included in the longitudinal outcome of canine (K9) myxomatous mitral valve disease (MMVD) registry (LOOK-mitral registry) and to evaluate the influence of the EPIC trial and other selected variables on cardiologist prescription habits. ANIMALS: The medical records of 6,102 dogs enrolled in the LOOK_mitral registry between 2015 and 2018 were retrospectively reviewed and 6,016 dogs were included. RESULTS: A medical treatment was prescribed by a cardiologist to 2,599 dogs (15% Stage-B1, 90% Stage-B2 and to all dogs in Stage-C). Angiotensin converting enzyme inhibitors (Ace-i) were the treatment most commonly prescribed for dogs in Stage-B1 (n = 352, 9%). The combination of pimobendan and an Ace-i was the most common treatment in Stage-B2 dogs (n = 367, 41%). Furosemide, an Ace-i, and pimobendan was the most common cardiac medical treatment prescribed for ACVIM Stage-C dogs (n = 704, 57%). Within each stage, dogs with larger left atrial and left ventricular dimensions were more likely to receive Ace-i, pimobendan or spironolactone. There was a four-fold increase in pimobendan prescription in Stage-B2 dogs after the publication of the EPIC trial. Moreover, a 15% reduction in Ace-i prescription and a 30% reduction in spironolactone prescription occurred after EPIC. In 974 dogs, a medical treatment was prescribed by the referring veterinarian. This was not changed (12%), modified (74%), or discontinued (14%) by the cardiologist. CONCLUSIONS: The EPIC trial and the echocardiographic assessment of left atrial and ventricular dimensions influence cardiologists' prescription habits.

Idioventricular tachycardia and unstable ventricular escape rhythm in a canine patient with third-degree atrioventricular block.

A 10-year-old female Labrador retriever was presented for evaluation and management of syncope. On presentation, idioventricular tachycardia (IT) was electrocardiographically evident but neither ventricular capture nor fusion complexes were recorded. Spontaneous termination of the IT resulted in prolonged ventricular asystole and revealed the underlying rhythm of third-degree atrioventricular block. The serum concentration of troponin-I was elevated, suggesting myocarditis, but this was not diagnostically confirmed. It is likely that overdrive suppression of subsidiary idioventricular pacemakers, and perhaps also disease of subsidiary ventricular pacemaker fibers, importantly contributed to the duration of asystole.

The Longitudinal Outcome Of Canine (K9) myxomatous mitral valve disease (LOOK-Mitral registry): Baseline characteristics.

INTRODUCTION: The Longitudinal Outcome Of Canine (K9) myxomatous mitral valve disease (MMVD) registry (LOOK-Mitral registry) was established to describe the natural history and predictors of outcome in dogs affected by MMVD. This study was intended to describe the baseline characteristics of dogs in the LOOK-mitral registry. ANIMALS: Dogs with echocardiographic evidence of MMVD were prospectively enrolled by thirteen referral centers. RESULTS: A total of 6102 dogs with MMVD were included. The median age was 10 years (1-19 years), and mixed breed was the most common breed (n = 1,360, 22%). Concomitant diseases were reported in 2459 dogs with chronic respiratory diseases occurring most frequently (14%), followed by the presence of azotemia (6%) and orthopedic diseases (5%). Regarding disease severity, 65% of dogs were in ACVIM Stage-B1, 15% in Stage-B2, and 20% in Stage-C. Dogs in Stage-B1 were younger (p<0.001) than dogs in other stages. Murmur intensity, heart rate during physical examination, and radiographic vertebral heart score were positively associated with the stage. Dogs in Stage-C were more likely to have tachypnea (p<0.001), dyspnea (p<0.001), cough (p<0.001), syncopal episodes (p<0.001), and tachyarrhythmias (p<0.001) compared to dogs in Stage-B1 and B2. Echocardiographic indices of left atrial and ventricular size were positively correlated with the ACVIM stage. Interestingly, 4% of dogs that weighed <20 kg had an increased normalized end-systolic left ventricle internal diameter (>1.26). CONCLUSIONS: This study contributes to a better understanding of the clinical characteristics of dogs affected by MMVD and provides new findings that may be of clinical relevance.

Accuracy of echocardiographically estimated pulmonary artery pressure in dogs with myxomatous mitral valve disease.

INTRODUCTION: Echocardiographically identified pulmonary hypertension is an independent predictor of poor outcome in dogs affected by myxomatous valvular degeneration (MMVD). Systolic pulmonary arterial pressure is routinely estimated based on its relationship with the Doppler-determined velocity of tricuspid regurgitation as defined by the simplified Bernoulli equation (sPAP_D). Experimental studies suggest that the method is imperfect, but its accuracy in dogs with MMVD is not known. ANIMALS: Twenty dogs affected by MMVD that had cardiac remodeling and measurable tricuspid regurgitation. METHODS: A flow-directed thermodilution monitoring catheter was percutaneously placed in the right external jugular vein and advanced to the main pulmonary artery. Pulmonary arterial systolic pressure was recorded (systolic pulmonary arterial pressure obtained by right heart catheterization [sPAP_C]). A second operator contemporaneously acquired tricuspid regurgitant velocity spectra to calculate sPAP_D. Each operator was blinded to the result of the other techniques. RESULTS: Technical difficulties prevented the analysis of catheterization data in two dogs. Eighteen measurement pairs were therefore used for comparison of sPAP_C and sPAP_D through correlation and Bland-Altman analysis. A statistically significant bias between sPAP_C and sPAP_D (mean difference = 0.5 mmHg; confidence interval = -6.5 mmHg, +7.5 mmHg) was not detected. The interval of agreement between the techniques was wide (-27.3 mmHg, +28.2 mmHg). A significant linear association between the two techniques was not identified (r = 0.11, p=0.17). CONCLUSION: Echocardiographically estimated pulmonary artery pressure poorly agrees with sPAP_C measurement in dogs affected by MMVD and cardiac remodeling with or without previously diagnosed congestive heart failure. In these dogs, sPAP_D could under- or over-estimate sPAP_C by more than 20 mmHg, and therefore caution should be used when interpreting sPAP_D.

Predictors of reoccurrence of congestive signs within 180 days after successful treatment of the first episode of congestive heart failure in dogs with myxomatous mitral valve disease.

INTRODUCTION: Myxomatous mitral valve disease (MMVD) is the most common cause of left-sided congestive heart failure in dogs. We sought to identify predictors of first reoccurrence of congestive signs (CS) within 180 days in dogs with MMVD and clinically stable heart failure. ANIMALS: A total of 445 dogs affected by stable American College of Veterinary Internal Medicine (ACVIM)-Stage-C MMVD were included, 106 in the reoccurrence group (RG) and 339 in no reoccurrence group (NRG). Patients were considered "stable" if medical treatment had been unchanged for at least 4 weeks since the first identification of CS. METHODS: Medical records of dogs with stable ACVIM-Stage-C MMVD included in a registry of dogs affected by MMVD were reviewed. Follow-up was required for inclusion in this investigation. Logistic regression was used to identify clinical and echocardiographic variables that independently predict first reoccurrence of CS. RESULTS: Baseline left atrial-aortic ratio (p=0.022, OR: 1.89, 90% CI: 1.20-2.98), left ventricular internal diameter at end-diastole (LVIDd_N) (p=0.014, OR: 2.84, 90% CI: 1.41-5.77), peak velocity of early diastolic transmitral flow (p=0.049, OR: 1.81, 90% CI: 1.10-3.00) and furosemide daily dosage (p=0.039, OR: 1.19, 90% CI: 1.04-1.37) were associated with reoccurrence of CS in univariable analyses. The LVIDd_N (p=0.014) remained significant in the multivariable analysis, but the area under the receiver operator characteristic curve was 0.57. CONCLUSION: This study failed to identify accurate predictors of reoccurrence of CS. However, dogs with larger value of LVIDd_N are more likely to have reoccurrence of CS within 180 days.

Prevalence and incidence of endometriosis in Australian women: a data linkage cohort study.

OBJECTIVE: To estimate the prevalence and incidence of endometriosis among Australian women. DESIGN: Population-based cohort study linked to administrative health records. SETTING: Secondary analysis of seven surveys collected between 2000 and 2018 from a population-based cohort study. POPULATION: A total of 13 508 Australian women, born 1973-78, from a prospective cohort study of 14 247 women conducted between 1996 and 2018. METHODS: During 2000 and 2018, self-reported longitudinal survey data were linked to three administrative health databases to separately identify women with clinically confirmed or suspected endometriosis across the multiple data sources. MAIN OUTCOME MEASURES: Prevalence and incidence of clinically confirmed endometriosis in the cohort were first estimated using national hospital data. Data were then combined with other administrative health databases and the survey data to capture all clinically confirmed and suspected diagnoses of endometriosis. RESULTS: The cumulative prevalence of clinically confirmed endometriosis was 6.0% (95% CI 5.8-6.2%) by age 40-44 years. The cumulative prevalence increased to 11.4% (95% CI 11.1-11.7%) when adding diagnoses of clinically suspected endometriosis. Age-specific incidence estimates peaked to 6 per 1000 person-years at age 30-34 years. CONCLUSIONS: Among 13 508 Australian women followed for 20 years, one in nine women had clinically confirmed or suspected endometriosis by the age of 44, with most diagnosed during their early thirties. Endometriosis is a significant public health issue requiring increased surveillance, clinical awareness and management. Efforts to expand knowledge on the aetiology of the disease and optimal methods for disease management are crucial to women's health. TWEETABLE ABSTRACT: In a national study of 13 508 Australian women, one in nine women were diagnosed with endometriosis by age 44.

Morphometry of the nulliparous pelvic floor.

OBJECTIVES: To describe morphometry of the pelvic floor in a large population of nulliparous women, comparing those with and those without pelvic pain. We also aimed to assess its association with characteristics such as age and body mass index (BMI). METHODS: This was a prospective study performed between January 2013 and November 2015 in non-pregnant nulliparous women attending a general gynecology clinic. Following collection of demographic data, women were examined using translabial four-dimensional (4D) ultrasound. Dynamic volumes of pelvic floor muscle were obtained at rest, on maximal contraction and on Valsalva maneuver, and analyzed at a later date by an assessor blinded to demographic details. Standard measurements for each volume included levator hiatal area and anteroposterior and transverse diameters, and pubovisceral muscle length and width. Subanalysis was performed comparing women with and those without pelvic pain. Linear regression analysis was performed to assess the association between characteristics, including age and BMI, and levator hiatal area at rest. RESULTS: Three hundred and sixty eight nulliparous women were examined using translabial 4D ultrasound. Median levator hiatal area was 10.62 cm2 at rest, 11.95 cm2 on Valsalva maneuver and 8.18 cm2 on maximal contraction. There was no difference between women with and those without pelvic pain when comparing biometric measurements of the pelvic floor musculature, except for in pubovisceral muscle width during the contraction phase. Regression analysis demonstrated that higher age and BMI were associated with increased levator hiatal area measurement. CONCLUSIONS: Pelvic floor morphometry in nulliparous women is unchanged by pelvic pain, but levator hiatal area is increased in women with higher BMI and age. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Longitudinal Analysis of Quality of Life, Clinical, Radiographic, Echocardiographic, and Laboratory Variables in Dogs with Preclinical Myxomatous Mitral Valve Disease Receiving Pimobendan or Placebo: The EPIC Study.

BACKGROUND: Changes in clinical variables associated with the administration of pimobendan to dogs with preclinical myxomatous mitral valve disease (MMVD) and cardiomegaly have not been described. OBJECTIVES: To investigate the effect of pimobendan on clinical variables and the relationship between a change in heart size and the time to congestive heart failure (CHF) or cardiac-related death (CRD) in dogs with MMVD and cardiomegaly. To determine whether pimobendan-treated dogs differ from dogs receiving placebo at onset of CHF. ANIMALS: Three hundred and fifty-four dogs with MMVD and cardiomegaly. MATERIALS AND METHODS: Prospective, blinded study with dogs randomized (ratio 1:1) to pimobendan (0.4-0.6 mg/kg/d) or placebo. Clinical, laboratory, and heart-size variables in both groups were measured and compared at different time points (day 35 and onset of CHF) and over the study duration. Relationships between short-term changes in echocardiographic variables and time to CHF or CRD were explored. RESULTS: At day 35, heart size had reduced in the pimobendan group: median change in (Δ) LVIDDN -0.06 (IQR: -0.15 to +0.02), P < 0.0001, and LA:Ao -0.08 (IQR: -0.23 to +0.03), P < 0.0001. Reduction in heart size was associated with increased time to CHF or CRD. Hazard ratio for a 0.1 increase in ΔLVIDDN was 1.26, P = 0.0003. Hazard ratio for a 0.1 increase in ΔLA:Ao was 1.14, P = 0.0002. At onset of CHF, groups were similar. CONCLUSIONS AND CLINICAL IMPORTANCE: Pimobendan treatment reduces heart size. Reduced heart size is associated with improved outcome. At the onset of CHF, dogs treated with pimobendan were indistinguishable from those receiving placebo.

Four-dimensional ultrasound guidance for pelvic floor Botulinum toxin-A injection in chronic pelvic pain: a novel technique.

OBJECTIVE: Botulinum toxin-A (BoNT-A) is used in the treatment of pelvic floor muscle overactivity associated with chronic pelvic pain (CPP) when conservative methods such as physiotherapy are not effective or appropriate. Traditional injection techniques require finger-guided palpation of pelvic floor muscles with concurrent insertion of the needle. The aim of this study was to describe a novel technique for the injection of BoNT-A into the pelvic floor musculature using four-dimensional ultrasound (4D-US) guidance. METHODS: Thirty-one BoNT-A injections were performed using the new technique between October 2013 and January 2016, on women scheduled to have BoNT-A injection for pelvic floor muscle overactivity and CPP. The pelvic floor was assessed by 4D-US. A test injection of saline was performed to confirm location of the needle, then BoNT-A was injected into the muscle under ultrasound guidance, using 4D-US to confirm that the fluid expanded and tracked along muscle fibers. RESULTS: The saline test confirmed correct location of the needle following a median of 1 (range, 1-3) attempt at needle placement. In all 31 instances, satisfactory injection of BoNT-A, with 4D-US confirmation of fluid expansion within the muscle body, was performed. CONCLUSIONS: Injection of BoNT-A under 4D-US guidance is feasible and allows accurate placement into the target muscle in women with pelvic floor muscle overactivity associated with CPP. This technique may provide a safer alternative to finger-guided methods, owing to a lower likelihood of operator needle-stick injury. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Measurement Variation and Repeatability of Echocardiographic Variables Used to Estimate Pulmonary Artery Pressure in Dogs.

BACKGROUND: Pulmonary hypertension (PH) is an important clinical entity in dogs. Pulmonary hypertension is generally identified based on echocardiographic findings, but measurement variation of the variables most often used in this context has not been reported. OBJECTIVE: To define measurement variation of echocardiographic variables that are used to estimate pulmonary artery pressure. ANIMALS: Four dogs with subclinical tricuspid valve regurgitation were selected from a hospital population. METHODS: Prospective descriptive study - dogs were subject to repeated echocardiographic examination by 2 operators. Each dog was echocardiographically examined 12 times, once by each operator during mornings and afternoons of 3 nonconsecutive days. Measurement variation was defined by coefficients of variation and by mean square errors (MSE) from ANOVA models. Repeatability coefficients (RC) were calculated from MSE. RESULTS: Of 50 within-day, between-day, and interoperator coefficients of variation (CVs), 37 were less than 10% and 46 were less than 15%. The range of peak velocity of tricuspid valve regurgitation (VTR) VTR was 1.87-3.34 m/s. Analysis of variance revealed a significant effect (P < 0.05) of operator for 7 of 10 measurements. Within-operator/between-day/within-subject and between-operator/between-day/within-subject RCs of VTR were, respectively, 0.3 and 0.6 m/s. CONCLUSIONS AND CLINICAL IMPORTANCE: With regard to repeatability, VTR is superior to other methods used for echocardiographic estimation of systolic pulmonary artery pressure. When TR is absent, the acceleration time of pulmonary ejection and the acceleration-to-ejection time ratio are alternative measures. A change in VTR exceeding 0.3 m/s might be outside the range of expected within-operator variation.

Endometriosis fertility index predicts live births following surgical resection of moderate and severe endometriosis.

STUDY QUESTION: Can live birth be accurately predicted following surgical resection of moderate-severe (Stage III-IV) endometriosis? SUMMARY ANSWER: Live births can accurately be predicted with the endometriosis fertility index (EFI), with adnexal function being the most important factor to predict non-assisted reproductive technology (non-ART) fertility or the requirement for ART (www.endometriosisefi.com). WHAT IS KNOWN ALREADY: Fertility prognosis is important to many women with severe endometriosis. Controversy persists regarding optimal post-operative management to achieve pregnancy and the counselling of patients regarding duration of conventional treatments before undergoing ART. The EFI is reported to correlate with expectant management pregnancy rate, although external validation has been performed without specifically addressing fertility in women with moderate and severe endometriosis. STUDY DESIGN, SIZE, DURATION: Retrospective cohort study of 279 women from September 2001 to June 2016. PARTICIPANTS/MATERIALS, SETTINGS, METHODS: We included women undergoing laparoscopic resection of Stage III-IV endometriosis who attempted pregnancy post-operatively. The EFI was calculated based on detailed operative reports and surgical images. Fertility outcomes were obtained by direct patient contact. Kaplan-Meier model, log rank test and Cox regression were used for analyses. MAIN RESULTS AND THE ROLE OF CHANCE: The follow-up rate was 84% with a mean duration of 4.1 years. A total of 147 women (63%) had a live birth following surgery, 94 of them (64%) without ART. The EFI was highly associated with live births (P < 0.001): for women with an EFI of 0-2 the estimated cumulative non-ART live birth rate at five years was 0% and steadily increased up to 91% with an EFI of 9-10, while the proportion of women who attempted ART and had a live birth, steadily increased from 38 to 71% among the same EFI strata (P = 0.1). A low least function score was the most significant predictor of failure (P = 0.003), followed by having had a previous resection (P = 0.019) or incomplete resection (P = 0.028), being older than 40 compared to <35 years of age (P = 0.027), and having leiomyomas (P = 0.037). LIMITATIONS REASONS FOR CAUTION: The main limitation of this study is its retrospective design. Imprecision was higher with low EFI due to smaller sample size in this subgroup. Finally, the EFI is somewhat subjective and could be prone to intra- and inter-observer variations. WIDER IMPLICATIONS OF THE FINDINGS: Women with a high EFI score have excellent fertility prognosis and may be advised to try to become pregnant with timed intercourse compared to women with a low score, for which prompt referral to ART seems more reasonable. Other prognostic factors can be used to guide the management of women with an intermediate EFI score. These data follow women over many years post-resection and represent longitudinal fertility data rarely demonstrated in such a cohort. The location and impact of lesions on the ability of the adnexa to function seems crucial for the fertility prognosis and should be further investigated. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by the GRACE Research funds. S.M.-L. is the recipient of a Training Award from the Fonds de Recherche Quebec-Sante. D.A. is the primary author of the Endometriosis Fertility Index. All authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.

Mitral valve repair in dogs using an ePTFE chordal implantation device: a pilot study.

OBJECTIVE: Mitral valve (MV) regurgitation due to degenerative MV disease is the leading cause of cardiac death in dogs. We carried out preliminary experiments to determine the feasibility and short-term effects of beating-heart MV repair using an expanded polytetrafluorethylene (ePTFE) chordal implantation device (Harpoon TSD-5) in dogs. ANIMALS: This study involved six healthy purpose-bred Beagles (weight range 8.9-11.4 kg). MATERIAL AND METHODS: Following a mini-thoracotomy performed under general anesthesia, the TSD-5 was used to place 1 or 2 artificial ePTFE cords on the anterior MV leaflet or the posterior MV leaflet via a left-ventricular transapical approach. The procedure was guided and monitored by transesophageal echocardiography. Postoperative antithrombotic treatment consisted of clopidogrel or a combination of clopidogrel and apixaban. Dogs were serially evaluated by transthoracic echocardiography at day 1, 7, 14, 21, and 30. The hearts were then examined for evaluation of tissues reactions and to detect signs of endothelialization. RESULTS: One or two chords were successfully implanted in five dogs. Four dogs completed the 30 days follow-up. One dog died intra-operatively because of aortic perforation. One dog died early post-operatively from a hemorrhagic pleural effusion attributed to overly aggressive antithrombotic treatment. One dog developed a thrombus surrounding both the knot and the synthetic cord. Postmortem exam confirmed secure placement of ePTFE knots in the mitral leaflets in all dogs and the presence of endothelialization of the knots and chords. CONCLUSIONS: These preliminary results demonstrate the feasibility of artificial chordal placement using an ePTFE cordal implantation device in dogs.

e-TC: Development and pilot testing of a web-based intervention to reduce anxiety and depression in survivors of testicular cancer.

e-TC is an online intervention designed to address common psychosocial concerns of testicular cancer survivors. It aims to reduce anxiety, depression and fear of cancer recurrence by providing evidence-based information and psychological intervention. This paper details the development and pilot testing of e-TC. During pilot testing, 25 men (with varying psychological profiles) who had completed treatment for testicular cancer, 6 months to 5 years ago (which had not recurred), used e-TC over a 10-week period and provided quantitative and qualitative feedback on the feasibility and acceptability of the programme. Six men also completed a qualitative interview to provide detailed feedback on their experiences using e-TC. Fourteen men (56%) completed at least 80% of the programme. Participants reported a high level of satisfaction with the programme. Men's limited time was a barrier to programme use and completion, and participants suggested that men with a more recent diagnosis and a higher level of distress may be more likely to engage with the programme. e-TC appears to be a feasible and acceptable online intervention for survivors of testicular cancer. Findings from this study are currently being used to refine e-TC and guide the design of a larger efficacy study.

Mitral valve morphology assessed by three-dimensional transthoracic echocardiography in healthy dogs and dogs with myxomatous mitral valve disease.

OBJECTIVE: To assess differences in morphology of the mitral valve (MV) between healthy dogs and dogs affected by myxomatous mitral valve disease (MMVD) using real-time transthoracic three-dimensional echocardiography (RT3DE). ANIMALS: Thirty-four were normal dogs and 79 dogs were affected by MMVD. METHODS: Real-time transthoracic three-dimensional echocardiography mitral datasets were digitally recorded and analyzed using dedicated software. The following variables were obtained and compared between healthy dogs and dogs with MMVD at different stages: antero-posterior annulus diameter, anterolateral-posteromedial annulus diameter, commissural diameter, annulus height, annulus circumference, annulus area, anterior leaflet length, anterior leaflet area, posterior leaflet length, posterior leaflet area, non-planar angle, annulus sphericity index, tenting height, tenting area, tenting volume, the ratio of annulus height and commissural diameter. RESULTS: Dogs with MMVD had a more circular MV annulus compared to healthy dogs as demonstrated by an increased annulus sphericity index (p=0.0179). Affected dogs had a less saddle-shaped MV manifest as a decreased annulus height to commissural width ratio (p=0.0004). Tenting height (p<0.0001), area (p<0.0001), and volume (p<0.0001) were less in affected dogs. CONCLUSIONS: Real-time transthoracic three-dimensional echocardiography analysis demonstrated that dogs affected by MMVD had a more circular and less saddle-shaped MV annulus, as well as reduced tenting height area and volume, compared to healthy dogs. Multiple variables differed between dogs at different stages of MMVD. Diagnostic and prognostic utility of these variables, and the significance of these changes in the pathogenesis and natural history of MMVD, require further attention.

Effect of Pimobendan in Dogs with Preclinical Myxomatous Mitral Valve Disease and Cardiomegaly: The EPIC Study-A Randomized Clinical Trial.

BACKGROUND: Pimobendan is effective in treatment of dogs with congestive heart failure (CHF) secondary to myxomatous mitral valve disease (MMVD). Its effect on dogs before the onset of CHF is unknown. HYPOTHESIS/OBJECTIVES: Administration of pimobendan (0.4-0.6 mg/kg/d in divided doses) to dogs with increased heart size secondary to preclinical MMVD, not receiving other cardiovascular medications, will delay the onset of signs of CHF, cardiac-related death, or euthanasia. ANIMALS: 360 client-owned dogs with MMVD with left atrial-to-aortic ratio ≥1.6, normalized left ventricular internal diameter in diastole ≥1.7, and vertebral heart sum >10.5. METHODS: Prospective, randomized, placebo-controlled, blinded, multicenter clinical trial. Primary outcome variable was time to a composite of the onset of CHF, cardiac-related death, or euthanasia. RESULTS: Median time to primary endpoint was 1228 days (95% CI: 856-NA) in the pimobendan group and 766 days (95% CI: 667-875) in the placebo group (P = .0038). Hazard ratio for the pimobendan group was 0.64 (95% CI: 0.47-0.87) compared with the placebo group. The benefit persisted after adjustment for other variables. Adverse events were not different between treatment groups. Dogs in the pimobendan group lived longer (median survival time was 1059 days (95% CI: 952-NA) in the pimobendan group and 902 days (95% CI: 747-1061) in the placebo group) (P = .012). CONCLUSIONS AND CLINICAL IMPORTANCE: Administration of pimobendan to dogs with MMVD and echocardiographic and radiographic evidence of cardiomegaly results in prolongation of preclinical period and is safe and well tolerated. Prolongation of preclinical period by approximately 15 months represents substantial clinical benefit.

Conventional echocardiographic assessment of the canine right heart: reference intervals and repeatability.

INTRODUCTION: We sought to define reference intervals for echocardiographic dimensions of the canine right heart. Secondarily, we intended to describe measurement variability of these dimensions. ANIMALS: Forty-five healthy adult pet dogs of diverse somatotype. MATERIALS AND METHODS: To obtain normative data used to define reference intervals, dogs underwent one echocardiographic examination by the same operator. Raw data were subject to logarithmic (log10) transformation and allometric relationships between body weight and echocardiographic variables were determined; reference intervals intended to include 95% of the population were defined. Six of the 45 dogs were randomly selected and subject to repeated echocardiographic examination by two operators. Measurement variability was quantified through calculation of coefficients of variation and repeatability coefficients. RESULTS: The strength of the linear relationships between log10 transformed echocardiographic variables and body weight varied; the range of coefficients of determination (R(2)) was 0.055-0.872. For most variables the scaling exponents were close to values expected based on presumed allometric relationships. Of the 190 within-day, between-day and inter-operator coefficients of variation generated, 165 (87%) were less than 15%. Analysis of variance revealed the operator to be a significant source of variation for 25 of 38 measurements. CONCLUSIONS: Reference intervals for echocardiographic dimensions and indices of right heart function are proposed. Repeatability of selected linear dimensions and areas obtained from two-dimensional echocardiography likely is sufficient for longitudinal clinical evaluations.

Assessment of mitral valve morphology using three-dimensional echocardiography. Feasibility and reference values.

OBJECTIVES: To evaluate the feasibility of real time transthoracic three-dimensional echocardiography (RT3DE) for evaluation of normal canine mitral valves (MVs), and to provide reference values for this technique. ANIMALS: Forty-three cardiologically healthy, not sedated dogs. METHODS: Transthoracic RT3DE mitral datasets were acquired during two consecutive 6-month periods. The datasets were analyzed using commercially available software. An MV model was drawn using a semiautomated procedure and MV variables were obtained and calculated. The ratio between annulus height and commissural diameter was used as an index of the annulus' saddle-shaped non-planarity. After evaluation of associations between measured variables and body size, the datasets were used to generate reference intervals. Coefficients of variation (CVs), variance components, and repeatability coefficients were calculated for the evaluation of intra-observer, inter-observer, and day-to-day variability. RESULTS: Datasets could be analyzed in 34 of 43 (79%) dogs. 68 percent of datasets obtained during the first 6-month period could be analyzed and 90% obtained during the second period could be analyzed. An allometric relationship was identified for most MV variables. The MV annulus appeared elliptical and saddle-shaped. Inter- and intra-observer CVs were less than 20%. Coefficient of variation greater than 20% was calculated for the inter-day variation for some variables. Operator and observer were primarily responsible for the variation of most of the variables. CONCLUSIONS: Evaluation of canine mitral valves by transthoracic RT3DE is feasible. Canine MVs of healthy dogs analyzed using RT3DE are elliptical and saddle-shaped. Reference intervals for the measured MV variables are proposed.