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Assessment of left atrial (LA) sizes in dogs informs clinical staging, risk assessment, treatment decisions, and prognosis. The objective of this study was to assess the diagnostic performance of observers with different levels of experience measuring the LA with three different techniques. Echocardiographic images from 36 dogs with different degrees of left atrial enlargement (LAE) were retrospectively retrieved, anonymized and measured in a blinded fashion by a veterinary student, a first-year cardiology resident, a third-year cardiology resident, and two board-certified veterinary cardiologists. The LA to aortic root ratio (LA:Ao), LA antero-postero diameter indexed to body weight (LAiAPD) and left atrial area were measured. Inter- and intra-observer intraclass correlation coefficients (ICCs) were calculated for all three variables. Bland-Altman plots and accuracy in identification of LAE were calculated for the three least experienced observers using LA:Ao and LAiAPD. Intra- and interobserver ICCs were greater than 0.9 for every variable. The observer with least experience had significant positive bias and a tendency to overestimate larger measurements using LA:Ao, but not using LAiAPD. The accuracy of identification of LAE also increased with the increasing level of experience and was higher for LAiAPD compared to LA:Ao. Combining both methods for identification of LAE, further increased accuracy.
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Pulmonary hypertension (PH), defined by increased pressure within the pulmonary vasculature, is a hemodynamic and pathophysiologic state present in a wide variety of cardiovascular, respiratory, and systemic diseases. The purpose of this consensus statement is to provide a multidisciplinary approach to guidelines for the diagnosis, classification, treatment, and monitoring of PH in dogs. Comprehensive evaluation including consideration of signalment, clinical signs, echocardiographic parameters, and results of other diagnostic tests supports the diagnosis of PH and allows identification of associated underlying conditions. Dogs with PH can be classified into the following 6 groups: group 1, pulmonary arterial hypertension; group 2, left heart disease; group 3, respiratory disease/hypoxia; group 4, pulmonary emboli/pulmonary thrombi/pulmonary thromboemboli; group 5, parasitic disease (Dirofilaria and Angiostrongylus); and group 6, disorders that are multifactorial or with unclear mechanisms. The approach to treatment of PH focuses on strategies to decrease the risk of progression, complications, or both, recommendations to target underlying diseases or factors contributing to PH, and PH-specific treatments. Dogs with PH should be monitored for improvement, static condition, or progression, and any identified underlying disorder should be addressed and monitored simultaneously.
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Doenças do Cão/diagnóstico , Hipertensão Pulmonar/veterinária , Sociedades Científicas/organização & administração , Medicina Veterinária/organização & administração , Animais , Doenças do Cão/terapia , Cães , Hipertensão Pulmonar/diagnóstico , Hipertensão Pulmonar/terapia , Guias de Prática Clínica como AssuntoRESUMO
Many viruses have been identified in pericardial fluid and in tissue samples from humans with pericarditis by means of molecular diagnostics. In canine idiopathic pericardial effusion there is as yet no conclusive evidence to support the involvement of an infectious agent. This study was designed to investigate a possible relationship between idiopathic pericardial effusion in dogs and viruses most commonly encountered in humans affected with viral pericarditis. Coxsackievirus B3 RNA, influenza virus type A RNA, human adenovirus type 2 DNA, human cytomegalovirus DNA, and parvovirus B19 DNA were investigated using PCR on pericardial effusion samples and pericardial tissue specimens collected from 14 dogs with idiopathic pericardial effusion. PCR was also used to test for two bacteria, Borrelia burgdorferi and Chlamydia pneumoniae. The same microorganisms were also looked for in pericardial effusions or pericardial washes from 10 dogs with neoplastic pericardial effusion, and in samples collected from 10 dogs which died of a non-cardiac disease. One pericardial effusion sample from a dog with the idiopathic form of the disease tested positive for influenza virus type A and sequencing of the amplicon confirmed the PCR result. In another dog from the same group a cytomegalovirus was detected by PCR in the effusion, but sequencing showed this to be a false-positive result. The genomes of the microorganisms investigated were not detected in neoplastic effusions or pericardial washes. The results indicate that viral and bacterial DNA/RNA of relevance for human pericarditis is rare in pericardial samples from dogs with idiopathic pericardial effusion. The finding of influenza type A viral RNA in pericardial fluid from one dog with the idiopathic form of the disease warrants further investigation.
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DNA Bacteriano/análise , DNA Viral/análise , Doenças do Cão/microbiologia , Derrame Pericárdico/veterinária , Animais , Doenças do Cão/virologia , Cães , Feminino , Vírus da Influenza A/genética , Vírus da Influenza A/isolamento & purificação , Masculino , Derrame Pericárdico/microbiologia , Derrame Pericárdico/virologia , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/veterináriaRESUMO
The aim of this study was to analyse the results of 6years (1999-2004) of mandatory breed screening for congenital heart disease in Boxer dogs using physical examination and echocardiography. Records of 1283 Boxers were reviewed and 165 dogs (12.86%) were found to be affected by heart disease, with aortic and pulmonic stenosis being the most frequent cardiac lesions. Comparison of these results with those of a previous survey showed a lower overall prevalence of both outflow obstructions, particularly of the more severe forms. A male predisposition for both aortic and pulmonic stenosis was evident from the study. Consistent with reports from other countries, soft left basilar heart murmurs were detected in both healthy dogs and dogs affected with congenital heart disease.
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Cruzamento/métodos , Doenças do Cão/epidemiologia , Cardiopatias Congênitas/veterinária , Animais , Doenças do Cão/genética , Cães , Feminino , Cardiopatias Congênitas/genética , Cardiopatias/epidemiologia , Cardiopatias/genética , Cardiopatias/veterinária , Sopros Cardíacos/epidemiologia , Sopros Cardíacos/genética , Sopros Cardíacos/veterinária , MasculinoRESUMO
OBJECTIVE: To investigate use of signal analysis of heart sounds and murmurs in assessing severity of mitral valve regurgitation (mitral regurgitation [MR]) in dogs with myxomatous mitral valve disease (MMVD). ANIMALS: 77 client-owned dogs. PROCEDURES: Cardiac sounds were recorded from dogs evaluated by use of auscultatory and echocardiographic classification systems. Signal analysis techniques were developed to extract 7 sound variables (first frequency peak, murmur energy ratio, murmur duration > 200 Hz, sample entropy and first minimum of the auto mutual information function of the murmurs, and energy ratios of the first heart sound [S1] and second heart sound [S2]). RESULTS: Significant associations were detected between severity of MR and all sound variables, except the energy ratio of S1. An increase in severity of MR resulted in greater contribution of higher frequencies, increased signal irregularity, and decreased energy ratio of S2. The optimal combination of variables for distinguishing dogs with high-intensity murmurs from other dogs was energy ratio of S2 and murmur duration > 200 Hz (sensitivity, 79%; specificity, 71%) by use of the auscultatory classification. By use of the echocardiographic classification, corresponding variables were auto mutual information, first frequency peak, and energy ratio of S2 (sensitivity, 88%; specificity, 82%). CONCLUSIONS AND CLINICAL RELEVANCE: Most of the investigated sound variables were significantly associated with severity of MR, which indicated a powerful diagnostic potential for monitoring MMVD. Signal analysis techniques could be valuable for clinicians when performing risk assessment or determining whether special care and more extensive examinations are required.
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Doenças do Cão/diagnóstico , Sopros Cardíacos/veterinária , Ruídos Cardíacos/fisiologia , Insuficiência da Valva Mitral/veterinária , Animais , Análise Discriminante , Cães , Ecocardiografia/veterinária , Feminino , Sopros Cardíacos/diagnóstico , Masculino , Valva Mitral/patologia , Insuficiência da Valva Mitral/diagnóstico , Análise de Regressão , Sensibilidade e Especificidade , Índice de Gravidade de DoençaRESUMO
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.
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Cardiomiopatia Hipertrófica/veterinária , Doenças do Gato/mortalidade , Animais , Cardiomiopatia Hipertrófica/mortalidade , Gatos , Feminino , Incidência , Masculino , Estudos Retrospectivos , Fatores de RiscoRESUMO
BACKGROUND: Myxomatous mitral valve disease (MMVD) is more prevalent in Cavalier King Charles Spaniels (CKCSs) compared to dogs of other breeds at a given age. Abnormal valvular stress is thought to contribute to the development and progression of MMVD, and a relationship exists between mitral valve (MV) morphology and stress acting on the valve. OBJECTIVES: To determine whether the MV morphology of healthy adult CKCSs differs from the morphology of healthy adult dogs of other breeds determined by RT-3DTTE. ANIMALS: Thirty-five healthy CKCSs and 41 healthy dogs of other breeds. METHODS: Prospective cross-sectional study. Dogs underwent physical examination, conventional echocardiography, and RT-3DTTE. RT-3DTTE datasets were analyzed using dedicated software for MV morphologic analysis. Morphologic variables were compared between CKCSs and dogs of other breeds. RESULTS: The MV of healthy CKCSs had a smaller annulus height (0.46 ± 0.11 vs. 0.56 ± 0.17; P = .0021), tenting height (0.26 ± 0.12 vs. 0.42 ± 0.18; P < .001), tenting area (0.42 ± 0.15 vs. 0.79 ± 0.34; P < .001), normalized tenting volume (0.09 [0.05-0.13] vs. 0.14 [0.10-0.20]; P < .001), and normalized area of the posterior leaflet (0.57 ± 0.15 vs. 0.66 ± 0.18; P = .016) compared to healthy dogs of other breeds; this results in CKCSs having a flatter MV with reduced tenting, compared to the MV of other breeds. CONCLUSIONS AND CLINICAL IMPORTANCE: These morphologic features could confer a mechanical disadvantage and play a role in the predisposition of CKCSs to the early development of MMVD.
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Ecocardiografia Tridimensional/veterinária , Valva Mitral/anatomia & histologia , Animais , Estudos Transversais , Cães , Feminino , Predisposição Genética para Doença , Masculino , Insuficiência da Valva Mitral/genéticaRESUMO
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.
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Cardiomiopatia Hipertrófica/veterinária , Doenças do Gato/mortalidade , Fatores Etários , Animais , Cardiomiopatia Hipertrófica/complicações , Cardiomiopatia Hipertrófica/mortalidade , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/veterinária , Estudos de Casos e Controles , Gatos , Ecocardiografia/veterinária , Feminino , Incidência , Masculino , Estudos Retrospectivos , Fatores de Risco , Análise de SobrevidaRESUMO
BACKGROUND: Systolic dysfunction associated with chronic mitral valve insufficiency (CMVI) has been demonstrated in experimental animal models and large breed (LB) dogs but has been reported as an uncommon finding in small breed (SB) dogs with naturally occurring disease. It has been suggested the myocardial failure could be, in part, because of an insufficient increase in left ventricular mass. HYPOTHESIS: To test if SB and LB dogs with CMVI and moderate heart failure have systolic dysfunction and if they have adequate eccentric hypertrophy. ANIMALS: Data from 38 SB and 18 LB dogs affected with CMVI were compared retrospectively with results from 2 groups of normal dogs (17 SB and 32 LB). METHODS: Systolic function was investigated echocardiographically by using percentage fractional shortening (FS), the ratio between observed and expected end-systolic diameter (ESD/ESDe), and end-systolic volume index (ESVI). Left ventricular hypertrophy was estimated by using the ratio between the thickness of the left ventricular free wall and the radius in diastole (h/R). RESULTS: Both affected SB and LB dogs had a significantly increased FS and ESVI (FS% SB 45.6 + 8.04 versus 40.06 + 8.9, P < .05; FS% LB 33.64 + 8.61 versus 27.3 + 7.3 P < .05; ESVI SB 30.0 +/- 2.3 mL/m2 versus 21.18 +/- 13.9 mL/m2, P < .05; ESVI LB 83.22 +/- 43.84 mL/m2 versus 36.43 +/- 13.30 mL/m2 versus P < .001). The h/R in affected animals was decreased (0.53 +/- 0.11 versus 0.41 +/- 0.12, P < .05 SB; 0.47 +/- 0.11 versus 0.38 +/- 0.09, P < .05, LB). CONCLUSIONS AND CLINICAL IMPORTANCE: Data from this study indicate that dogs with moderate heart failure caused by CMVI have systolic dysfunction. Inadequate hypertrophy of the left ventricle may be, in part, responsible for this finding.
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Tamanho Corporal , Doenças do Cão/patologia , Hipertrofia Ventricular Esquerda/veterinária , Insuficiência da Valva Mitral/veterinária , Remodelação Ventricular , Animais , Doença Crônica , Cães , Feminino , Hipertrofia Ventricular Esquerda/patologia , Masculino , Insuficiência da Valva Mitral/patologiaRESUMO
The most common heart disease that affects dogs is myxomatous mitral valve disease. In this article, we review the current diagnostic and therapeutic approaches to this disease, and we also present some of the latest technological advancements in this field.
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The purpose of this study was to investigate the prognostic value of various clinical, ECG, echocardiographic, and Doppler echocardiographic variables in dogs with dilated cardiomyopathy. The relationship to survival of 11 variables was evaluated in 63 dogs. Studied variables were age at time of diagnosis, class of heart failure (HF), dyspnea, ascites, atrial fibrillation (AF), ejection fraction (EF), E-point septal separation, end-diastolic volume index, end-systolic volume index (ESV-I), and restrictive or nonrestrictive transmitral flow (TMF) pattern. Median survival time was 671 days (lower 95% confidence limit, 350 days). Survival curves showed that severity of HF, ascites, ESV-I greater than 140 mL/m2, EF less than 25%, and restrictive TMF pattern had a significant negative relation to survival time. Thirty-nine dogs with both sinus rhythm and AF presented adequate TMF recordings; in these dogs, after stratification by TMF pattern, the restrictive TMF pattern was the most important negative prognostic indicator. We conclude that in dogs with dilated cardiomyopathy the restrictive TMF pattern appears to represent a useful prognostic indicator. Class of HF, ascites, ESV-I, and EF are also useful indexes if an adequate TMF pattern is not recorded.
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Cardiomiopatia Dilatada/veterinária , Doenças do Cão/diagnóstico , Animais , Cardiomiopatia Dilatada/diagnóstico , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/mortalidade , Doenças do Cão/diagnóstico por imagem , Doenças do Cão/mortalidade , Cães , Ecocardiografia/veterinária , Eletrocardiografia/veterinária , Feminino , Insuficiência Cardíaca/veterinária , Masculino , Prognóstico , Estudos RetrospectivosRESUMO
Renal biopsies were carried out on 229 dogs using an echo-assisted, semi-automatic method. Complications arising after the biopsy were also evaluated. The biopsies were examined for the accuracy of diagnosis and the presence of histologically demonstrable primary renal pathologies. A retrospective study of the observed lesions and parenchymal echogenicity showed a correlation between these factors involving the tubulo-interstitial compartment. Histopathological renal lesions and their correlation with laboratory methods are the only parameters that allow a correct diagnostic, prognostic, and therapeutic work-up in cases of clinical kidney disease in canines.
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Biópsia por Agulha Fina/veterinária , Doenças do Cão/patologia , Proteinúria/patologia , Insuficiência Renal/patologia , Animais , Biópsia por Agulha Fina/métodos , Cães , Feminino , Masculino , Estudos RetrospectivosRESUMO
OBJECTIVE: To histologically identify glomerular lesions in dogs infected with Leishmania organisms. ANIMALS: 41 dogs (17 sexually intact males and 14 sexually intact and 10 ovariohysterectomized females) that had positive results when tested for leishmaniosis as determined by use of serologic evaluation (indirect fluorescent antibody test, titers of 1:80 to 1:640) and direct microscopic identification of the protozoal organisms. PROCEDURE: Urine samples were collected by use of cystocentesis and examined by qualitative SDS-agarose gel electrophoresis (AGE). All dogs had non-selective (glomerular) or mixed (glomerular and tubular) proteinemia. Specimens were obtained from each dog during ultrasound-assisted renal biopsy and used for histologic examination. Each specimen was stained with H&E, periodic acid-Schiff, Goldner's trichrome, methenamine silver, and Congo Red stains. Specimens were adequate for evaluation when they contained at least 5 glomeruli/section, except for specimens stained with Congo Red in which 1 glomerulus/section was adequate. RESULTS: Examination of renal biopsy specimens revealed various glomerular lesions in all dogs and interstitial or tubular (or both) lesions in 23 of 41 (55%) dogs. CONCLUSIONS AND CLINICAL RELEVANCE: Glomerular lesions that develop in dogs during infection with Leishmania organisms can be classified histologically as mesangial glomerulonephritis, membranous glomerulonephritis, membranoproliferative glomerulonephritis, and focal segmental glomerulonephritis. Tubulointerstitial histopathologic conditions were not observed as the primary lesion, despite being evident in 23 of 41 (55%) dogs. Use of SDS-AGE for qualitative evaluation of proteinuria and successive collection of specimens during renal biopsies following diagnosis of nonselective glomerular proteinuria provides the possibility for early identification of renal lesions.
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Doenças do Cão/patologia , Doenças do Cão/parasitologia , Glomérulos Renais/patologia , Leishmaniose/patologia , Leishmaniose/veterinária , Animais , Doenças do Cão/urina , Cães , Feminino , Leishmaniose/complicações , Leishmaniose/urina , Masculino , Proteinúria/complicaçõesRESUMO
The therapeutic effect of mesenchymal stromal cells (MSCs) following myocardial infarction (MI) is small. This may be due to differences in cellular sources and donor age, route of administration, in vitro cellular manipulations and the short time course of follow up in many animal studies. Here, we compared MSCs from two different sources (adult bone marrow or Wharton's jelly from umbilical cord) for their long-term therapeutic effect following MI in a rat model to evaluate the effect of donor age. MSCs (or control infusions) were given intravenously 24-48 hr after myocardial ischemia (MI) induced by coronary artery ligation. Cardiac function was assessed by ultrasound at time points starting from before MSC infusion through 68 weeks after MI. A significant improvement in ejection fraction was seen in animals that received MSCs in time points 25 to 31 wks after treatment (p < 0.01). These results support previous work that show that MSCs can cause improvement in cardiac function and extend that work by showing that the beneficial effects are durable. To investigate MSCs' cardiac differentiation potential, Wharton's jelly MSCs were co-cultured with fetal or adult bone-derived marrow MSCs. When Wharton's jelly MSCs were co-cultured with fetal MSCs, and not with adult MSCs, myotube structures were observed in two-three days and spontaneous contractions (beating) cells were observed in fiveseven days. The beating structures formed a functional syncytium indicated by coordinated contractions (beating) of independent nodes. Taken together, these results suggest that MSCs given 24-48 hr after MI have a significant and durable beneficial effect more than 25 weeks after MI and that MSC treatment can home to damaged tissue and improve heart function after intravenous infusion 24-48 hrs after MI, and that WJCs may be a useful source for off-the-shelf cellular therapy for MI.
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Medula Óssea , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Infarto do Miocárdio/prevenção & controle , Geleia de Wharton/citologia , Animais , Diferenciação Celular , Separação Celular , Células Cultivadas , Técnicas de Cocultura , Feminino , Feto , Infarto do Miocárdio/patologia , RatosRESUMO
Chronic mitral valve disease due to myxomatous degeneration (MMVD) is the most common cardiovascular disease in dogs and has been known to cause congestive heart failure for more than 100 years. This article presents an historical perspective of the disease and reviews the most updated data on epidemiology and natural history of MMVD in dogs.
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Doenças do Cão/epidemiologia , Insuficiência da Valva Mitral/veterinária , Envelhecimento , Animais , Doenças do Cão/genética , Doenças do Cão/patologia , Cães , Insuficiência da Valva Mitral/epidemiologia , Insuficiência da Valva Mitral/genética , Insuficiência da Valva Mitral/patologiaRESUMO
OBJECTIVE: To evaluate reproducibility of ejection fraction (EF), myocardial perfusion (MP), and pulmonary transit time (PTT) measured in a group of dogs by use of contrast echocardiography and to examine safety of this method by evaluating cardiac troponin I concentrations. ANIMALS: 6 healthy dogs. PROCEDURES: 2 bolus injections and a constant rate infusion of contrast agent were administered IV. Echocardiographic EF was determined by use of the area-length method and was calculated without and with contrast agent. The PTT and normalized PTT (PTT/mean R-R interval) were measured for each bolus. Constant rate infusion was used for global MP evaluation, and regional MP was calculated by use of a real-time method in 4 regions of interest of the left ventricle. Cardiac troponin I concentration was analyzed before and after contrast agent administration. Intraoberserver and interobserver variability was calculated. RESULTS: EF was easier to determine with the ultrasonographic contrast agent. For the first and second bolus, mean ± SD PTT was 1.8 ± 0.2 seconds and 2.1 ± 0.3 seconds and normalized PTT was 3.4 ± 0.3 seconds and 3.5 ± 0.3 seconds, respectively. A coefficient of variation < 15% was obtained for global MP but not for the regional MPs. No differences were detected between precontrast and postcontrast cardiac troponin I concentrations. CONCLUSIONS AND CLINICAL RELEVANCE: Contrast echocardiography appeared to be a repeat-able and safe technique for use in the evaluation of global MP and PTT in healthy dogs, and it improved delineation of the endocardial border in dogs.
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Ecocardiografia/veterinária , Imagem de Perfusão do Miocárdio/veterinária , Circulação Pulmonar/fisiologia , Animais , Meios de Contraste/farmacologia , Cães , Feminino , Masculino , Microbolhas , Imagem de Perfusão do Miocárdio/métodos , Reprodutibilidade dos Testes , Volume Sistólico/fisiologiaRESUMO
OBJECTIVE: To describe the pharmacokinetics of oral pimobendan in healthy cats. ANIMALS: 18 purpose-bred cats. METHODS: In 10 cats, blood samples were collected before, and at multiple time points after, a single oral dose of pimobendan (0.28 ± 0.04 mg/kg). In 8 cats, blood samples were collected at 3 various time points on the first and third days of twice daily oral dosing of pimobendan for a total of 7 doses (0.31 ± 0.04 mg/kg). Plasma concentrations of pimobendan were quantified by high pressure liquid chromatography coupled to tandem mass spectrometry. RESULTS: A 1-compartment open model with first order absorption in and elimination from the central compartment with a lag time best describes the disposition of pimobendan. Two cats were removed from final pharmacokinetic descriptive analysis due to delayed minimal absorption from gastrointestinal adverse effects. After a lag time (0.3 ± 0.06 h), pimobendan was rapidly absorbed (absorption half-life = 0.2 ± 0.08 h) and eliminated (elimination half-life = 1.3 ± 0.2 h). Maximum plasma concentrations (34.50 ± 6.59 ng/mL) were high and were predicted 0.9 h after drug administration. Apparent volume of distribution at steady state (per bioavailability) was large (8.2 ± 2.5 L/kg). The multi-dose study showed the pharmacokinetic model to be robust. CONCLUSION: When administered a similar dose on a per weight basis, pimobendan has a substantially longer elimination half-life and maximal drug plasma concentration in cats as compared to those previously reported in dogs.
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Cardiotônicos/farmacocinética , Gatos/metabolismo , Piridazinas/farmacocinética , Administração Oral , Animais , Disponibilidade Biológica , Cardiotônicos/administração & dosagem , Cardiotônicos/sangue , Gatos/sangue , Esquema de Medicação , Feminino , Meia-Vida , Masculino , Projetos Piloto , Piridazinas/administração & dosagem , Piridazinas/sangue , Fatores de TempoRESUMO
OBJECTIVE: To compare echocardiographic variables of dogs with postmortem anatomic measurements and histologic characteristics of the mitral valve (MV). ANIMALS: 21 cardiologically normal dogs. PROCEDURES: The MV was measured echocardiographically by use of the right parasternal 5-chamber long-axis view. Dogs were euthanized, and anatomic measurements of the MV annulus (MVa) were performed at the level of the left circumflex coronary artery. Mitral valve leaflets (MVLs) and chordae tendineae were measured. Structure of the MVLs was histologically evaluated in 3 segments (proximal, middle, and distal). RESULTS: Echocardiographic measurements of MVL length did not differ significantly from anatomic measurements. A positive correlation was detected between body weight and MVa area. There was a negative correlation between MVa area and the percentage by which the MVL area exceeded the MVa area. Anterior MVLs had a significantly higher number of chordae tendineae than did posterior MVLs. Histologically, layering of MVLs was less preserved in the distal segment, whereas the muscular component and adipose tissue were significantly more diffuse in the proximal and middle segments. CONCLUSIONS AND CLINICAL RELEVANCE: The MV in cardiologically normal dogs had wide anatomic variability. Anatomic measurements of MVL length were correlated with echocardiographic measurements.
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Cordas Tendinosas/anatomia & histologia , Cães/anatomia & histologia , Ecocardiografia/métodos , Valva Mitral/anatomia & histologia , Animais , Cordas Tendinosas/diagnóstico por imagem , Ecocardiografia/veterinária , Feminino , Masculino , Valva Mitral/diagnóstico por imagemRESUMO
OBJECTIVE: To investigate whether plasma activity of matrix metalloproteinase (MMP)-2 and -9 was associated with severity of myxomatous mitral valve disease (MMVD) in dogs and to assess potential associations between MMP activity and dog characteristics, echocardiographic variables, systolic arterial blood pressure (SAP), heart rate, cardiac troponin I (cTnI) concentration, and C-reactive protein concentration. ANIMALS: 75 client-owned dogs. PROCEDURES: Severity of MMVD was assessed by use of echocardiography. Plasma activity of latent (pro-MMP) and active MMP-2 and -9 was analyzed via zymography. Plasma concentration of cTnI was analyzed with a high-sensitivity cTnI assay, and C-reactive protein concentration was analyzed with a canine-specific ELISA. RESULTS: Pro-MMP-9, active MMP-9, and pro-MMP-2 were detected, but active MMP-2 was not. No significant differences were found in MMP concentrations among the 4 MMVD severity groups. Activity of pro-MMP-9 decreased with decreases in SAP and was higher in male dogs than in female dogs. Activity of MMP-9 decreased with increases in left ventricular end-systolic dimension and with decreases in SAP and cTnI concentration. Left ventricular end-systolic dimension was the variable most strongly associated with MMP-9 activity. No associations were found between the activity of pro-MMP-2 and investigated variables. CONCLUSIONS AND CLINICAL RELEVANCE: Plasma MMP-9 activity decreased with increases in the end-systolic left ventricular internal dimension and decreases in SAP. Hence, evaluation of MMP-9 activity has the potential to provide unique information about the myocardial remodeling process in dogs with MMVD.
Assuntos
Proteína C-Reativa/análise , Doenças do Cão/fisiopatologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Insuficiência da Valva Mitral/veterinária , Troponina I/sangue , Animais , Biomarcadores , Pressão Sanguínea , Doenças do Cão/sangue , Doenças do Cão/patologia , Cães , Ecocardiografia/veterinária , Eletroforese em Gel de Poliacrilamida/veterinária , Precursores Enzimáticos/sangue , Precursores Enzimáticos/metabolismo , Ensaio de Imunoadsorção Enzimática/veterinária , Feminino , Coração/fisiopatologia , Frequência Cardíaca , Masculino , Metaloproteinase 2 da Matriz/sangue , Metaloproteinase 9 da Matriz/sangue , Valva Mitral/patologia , Insuficiência da Valva Mitral/sangue , Insuficiência da Valva Mitral/patologia , Insuficiência da Valva Mitral/fisiopatologia , Análise Multivariada , Análise de Regressão , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Especificidade da EspécieRESUMO
Myxomatous mitral valve disease is a common condition in geriatric dogs. Most dogs affected are clinically asymptomatic for a long time. However, about 30% of these animals present a progression to heart failure and eventually die as a consequence of the disease. Left atrial enlargement, and particularly a change in left atrial size, seems to be the most reliable predictor of progression in some studies, however further studies are needed to clarify how to recognize asymptomatic patients at higher risk of developing heart failure. According to the published data on the natural history of the disease and the results of published studies evaluating the effect of early therapy on delaying the progression of the disease, it seems that no currently available treatment delays the onset of clinical signs of congestive heart failure (CHF). Although the ideal treatment of more severely affected dogs is probably surgical mitral valve repair or mitral valve replacement, this is not a currently available option. The results of several clinical trials together with clinical experience suggest that dogs with overt CHF can be managed with acceptable quality of life for a relatively long time period with medical treatment including furosemide, an angiotensin-converting enzyme inhibitor, pimobendan, and spironolactone.