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OBJECTIVE: To characterize the dose-exposure-response effect of spironolactone on biomarkers of the classical and alternative arms of the renin-angiotensin-aldosterone system (RAAS) in healthy dogs. ANIMALS: Ten healthy purpose-bred Beagle dogs. PROCEDURES: Study dogs were randomly allocated to 2 spironolactone dosing groups (2 mg/kg PO q24hr, 4 mg/kg PO q24hr). The dogs received 7-day courses of spironolactone followed by a 14-day washout period in a crossover (AB/BA) design. Angiotensin peptides and aldosterone were measured in serum using equilibrium analysis, and plasma canrenone and 7-α-thiomethyl spironolactone (TMS) were quantified via liquid chromatography-mass spectrometry/mass spectroscopy (LC-MS/MS). Study results were compared before and after dosing and between groups. RESULTS: Following spironolactone treatment, dogs had a significant increase in serum aldosterone concentration (P = 0.07), with no statistical differences between dosing groups. Significant increases in angiotensin II (P = 0.09), angiotensin I (P = 0.08), angiotensin 1-5 (P = 0.08), and a surrogate marker for plasma renin activity (P = 0.06) were detected compared to baseline following spironolactone treatment during the second treatment period only. Overall, changes from baseline did not significantly differ between spironolactone dosages. RAAS analytes were weakly correlated (R < 0.4) with spironolactone dosage and plasma canrenone or plasma TMS. There were no adverse clinical or biochemical effects seen at any spironolactone dosage during treatment. CONCLUSIONS: Treatment with spironolactone increased serum aldosterone concentration in healthy dogs and impacted other biomarkers of the classical and alternative arms of the RAAS. There was no difference in effect on the RAAS between 2 and 4 mg/kg/day dosing. Dosage of 4 mg/kg/day was safe and well-tolerated in healthy dogs.
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Sistema Renina-Angiotensina , Espironolactona , Cães , Animais , Espironolactona/farmacologia , Espironolactona/uso terapêutico , Aldosterona , Antagonistas de Receptores de Mineralocorticoides/farmacologia , Receptores de Mineralocorticoides/metabolismo , Canrenona/farmacologia , Cromatografia Líquida , Espectrometria de Massas em Tandem , Angiotensina II/farmacologia , BiomarcadoresRESUMO
BACKGROUND: Systemic hypertension (SH) is a common cardiovascular disease in older cats that is treated primarily with the calcium channel blocker amlodipine besylate (AML). The systemic effect of AML on the classical and alterative arms of the renin-angiotensin-aldosterone system (RAAS) in cats is incompletely characterized. HYPOTHESIS/OBJECTIVES: To determine the effect of AML compared to placebo on circulating RAAS biomarkers in healthy cats using RAAS fingerprinting. ANIMALS: Twenty healthy client-owned cats. METHODS: Cats were administered amlodipine besylate (0.625 mg in toto) or placebo by mouth once daily for 14 days in a crossover design with a 4-week washout period. Plasma AML concentrations and RAAS biomarker concentrations were measured at multiple timepoints after the final dose in each treatment period. Time-weighted averages for RAAS biomarkers over 24 hours after dosing were compared between treatment groups using Wilcoxon rank-sum testing. RESULTS: Compared to placebo, AML treatment was associated with increases in markers of plasma renin concentration (median 44% increase; interquartile range [IQR] 19%-86%; P = .009), angiotensin I (59% increase; IQR 27-101%; P = .006), angiotensin II (56% increase; IQR 5-70%; P = .023), angiotensin IV (42% increase; -19% to 89%; P = .013); and angiotensin 1-7 (38% increase; IQR 9-118%; P = .015). CONCLUSIONS AND CLINICAL IMPORTANCE: In healthy cats, administration of AML resulted in nonspecific activation of both classical and alternative RAAS pathways.
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Anlodipino , Sistema Renina-Angiotensina , Animais , Gatos , Aldosterona , Anlodipino/farmacologia , Anti-Hipertensivos/farmacologia , Biomarcadores , Sistema Renina-Angiotensina/efeitos dos fármacos , Sistema Renina-Angiotensina/fisiologiaRESUMO
BACKGROUND: Predicting progression of myxomatous mitral valve disease (MMVD) in dogs can be challenging. HYPOTHESIS/OBJECTIVES: The mitral regurgitation severity index (MRSI) will predict time to congestive heart failure (CHF) and all-cause death in dogs with MMVD. ANIMALS: Eight hundred sixty-nine client-owned dogs. METHODS: Retrospective study pooling data from 4 previous samples including dogs with MMVD stage B2 or C. MRSI was calculated as: (heart rate [HR]/120) × left atrium-to-aorta ratio (LA:Ao) × (age in years/10) × 100. Alternative MRSI formulas substituting radiographic measures of left atrial size were also calculated. Cox proportional hazard modeling and time-dependent receiver-operator characteristic curves quantified prognostic performance. RESULTS: For Stage B2 pooled samples, MRSI > 156 was predictive of time to CHF (median 407 vs 1404 days; area under the curve [AUC] 0.68; hazard ratio 3.02 [95% CI 1.9-4.9]; P < .001). MRSI > 173 was predictive of all-cause death (median survival 868 vs 1843 days; AUC 0.64; hazard ratio 4.26 [95% CI 2.4-7.5]; P < .001). MRSI showed superior predictive value compared to the individual variables of HR, LA:Ao, and age. Variations of the MRSI equation substituting radiographic vertebral left atrial size for LA:Ao were also significantly predictive of outcome in stage B2. MRSI was not consistently predictive of outcome in Stage C. CONCLUSIONS AND CLINICAL IMPORTANCE: MRSI was predictive of outcome (onset of CHF and all-cause death) in MMVD Stage B2, demonstrating utility as a useful prognostic tool. Echocardiographic LA:Ao can be effectively replaced by radiographically determined LA size in the MRSI formula.
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Doenças do Cão , Insuficiência Cardíaca , Doenças das Valvas Cardíacas , Insuficiência da Valva Mitral , Humanos , Cães , Animais , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/veterinária , Valva Mitral , Estudos Retrospectivos , Doenças do Cão/diagnóstico por imagem , Doenças das Valvas Cardíacas/veterinária , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/veterináriaRESUMO
Point-of-care ultrasound (POCUS) is a useful imaging tool for the diagnosis and monitoring of cardiac emergencies. Unlike complete echocardiography, POCUS is a time-sensitive examination involving a subset of targeted thoracic ultrasound views to identify abnormalities of the heart, lungs, pleural space, and caudal vena cava. When integrated with other clinical information, POCUS can be helpful in the diagnosis of left-sided and right-sided congestive heart failure, pericardial effusion and tamponade, and severe pulmonary hypertension and can help clinicians monitor resolution or recurrence of these conditions.
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BACKGROUND: The prevalence and clinical characteristics of different etiologies of peripheral edema in dogs are unknown. HYPOTHESIS/OBJECTIVES: To determine the prevalence of different etiologies of peripheral edema, describe clinical characteristics that vary among etiologies, and report survival times. ANIMALS: Five hundred twenty-seven dogs with peripheral edema. METHODS: Retrospective medical record review. Differences in clinical variables among etiology groups were assessed by Kruskal-Wallis testing with post hoc pairwise Dunn's testing and Chi-square testing with Monte Carlo simulation. RESULTS: The most common etiologies of peripheral edema in dogs were vasculitis (n = 193, 37%), lymphatic/venous obstruction (LVO; 114, 22%), and hypoalbuminemia (94, 18%). Right-sided congestive heart failure (R-CHF) was uncommon (25, 5%). Edema was localized in 377 (72%) dogs and generalized in 142 (27%) dogs, and hypoalbuminemia was more likely to cause generalized edema compared to LVO or vasculitis (P < .0001). Concurrent abdominal effusion (155, 29%) was more common than pleural (77, 15%) or pericardial (12, 2%) effusion. Abdominal and pleural effusion occurred more commonly in dogs with hypoalbuminemia or R-CHF compared to LVO or vasculitis (P < .0001). CONCLUSIONS AND CLINICAL IMPORTANCE: Distribution of edema, concurrent cavitary effusions, and clinicopathological data can help predict the underlying etiology of peripheral edema in dogs.
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Doenças do Cão , Insuficiência Cardíaca , Hipoalbuminemia , Derrame Pleural , Vasculite , Cães , Animais , Hipoalbuminemia/complicações , Hipoalbuminemia/veterinária , Estudos Retrospectivos , Edema/etiologia , Edema/veterinária , Derrame Pleural/veterinária , Insuficiência Cardíaca/veterinária , Insuficiência Cardíaca/complicações , Vasculite/complicações , Vasculite/veterinária , Doenças do Cão/etiologia , Doenças do Cão/patologiaRESUMO
The functional capacities of animals are a primary factor determining survival in nature. In this context, understanding the biomechanical performance of animals can provide insight into diverse aspects of their biology, ranging from ecological distributions across habitat gradients to the evolutionary diversification of lineages. To survive and reproduce in the face of environmental pressures, animals must perform a wide range of tasks, some of which entail tradeoffs between competing demands. Moreover, the demands encountered by animals can change through ontogeny as they grow, sexually mature or migrate across environmental gradients. To understand how mechanisms that underlie functional performance contribute to survival and diversification across challenging and variable habitats, we have pursued diverse studies of the comparative biomechanics of amphidromous goby fishes across functional requirements ranging from prey capture and fast-start swimming to adhesion and waterfall climbing. The pan-tropical distribution of these fishes has provided opportunities for repeated testing of evolutionary hypotheses. By synthesizing data from the lab and field, across approaches spanning high-speed kinematics, selection trials, suction pressure recordings, mechanical property testing, muscle fiber-type measurements and physical modeling of bioinspired designs, we have clarified how multiple axes of variation in biomechanical performance associate with the ecological and evolutionary diversity of these fishes. Our studies of how these fishes meet both common and extreme functional demands add new, complementary perspectives to frameworks developed from other systems, and illustrate how integrating knowledge of the mechanical underpinnings of diverse aspects of performance can give critical insights into ecological and evolutionary questions.
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Evolução Biológica , Peixes , Animais , Fenômenos Biomecânicos , Peixes/fisiologia , Natação , EcossistemaRESUMO
Harmful algal blooms are a growing environmental concern in aquatic systems. Although it is known that some of the secondary metabolites produced by cyanobacteria can alter predator-prey dynamics in aquatic communities by reducing foraging and/or predator evasion success, the mechanisms underpinning such responses are largely unknown. In this study, we examined the effects of a potent algal neurotoxin, ß-N-methylamino-L-alanine (BMAA), on the development and behavior of larval Fathead Minnows, Pimephales promelas, during predator-prey interactions. We exposed eggs and larvae to environmentally relevant concentrations of BMAA for 21 days, then tested subjects in prey-capture and predator-evasion assays designed to isolate the effects of exposure at sequential points of the stimulus-response pathway. Exposure was associated with changes in the ability of larvae to detect and respond to environmental stimuli (i.e., a live prey item and a simulated vibrational predator), as well as changes in behavior and locomotor performance during the response. Our findings suggest that chronic exposure to neurodegenerative cyanotoxins could alter the outcomes of predator-prey interactions in natural systems by impairing an animal's ability to perceive, process, and respond to relevant biotic stimuli.
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Cyprinidae , Poluentes Químicos da Água , Animais , Larva , Comportamento Predatório , Poluentes Químicos da Água/toxicidade , Cyprinidae/fisiologiaRESUMO
OBJECTIVE: To determine the diagnostic utility of a smartphone-based ECG device (Alivecor KardiaMobile) in awake bonobos (Pan paniscus). ANIMALS: 7 adult bonobos in human care. PROCEDURES: Bonobos were trained with positive reinforcement to hold 1 finger from each hand onto the KardiaMobile sensors for 30 seconds to obtain an ECG reading. Ten ECG tracings were recorded from each bonobo and evaluated by a veterinarian, a veterinary cardiologist, and a human cardiologist for tracing quality, tracing length, heart rate, identification of P-waves, and presence and quantification of premature ventricular or atrial contractions. RESULTS: 6 of the 7 bonobos were trained within 21 weeks to allow the collection of 10 diagnostic quality ECG tracings. The average heart rate recorded was 87 bpm (range = 60 to 118 bpm). Potential abnormalities identified by the KardiaMobile included premature ventricular contractions in 2 male bonobos and 1 premature atrial contraction in another male. There was strong agreement by reviewers in all ECG parameters except for the identification of P-waves. CLINICAL RELEVANCE: The Alivecor KardiaMobile device has diagnostic utility as a screening tool for use in bonobos in human care. The training was accomplished to yield diagnostic ECG readings of acceptable duration in awake bonobos. Given the prevalence of cardiovascular disease in great apes, this technology may identify a subset of great apes who may benefit from early intervention and treatment in an effort to delay the progression of cardiac disease.
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Pan paniscus , Vigília , Humanos , Masculino , Animais , Pan paniscus/fisiologia , Smartphone , Frequência Cardíaca , Eletrocardiografia/veterinária , Pan troglodytesRESUMO
Borzoi are large, relatively uncommon sighthounds anecdotally reported to suffer from sudden death. This multicenter retrospective cohort study aimed to describe the sample of Borzoi presenting to veterinary cardiologists for evaluation, with records searched from 14 centers across a study period of up to 20 years. The study sample was comprised of 152 client-owned Borzoi, with dogs most commonly presenting for pre-breed screening in 87/152 (52%), followed by evaluation of an arrhythmia in 28/152 (18%). Of the 131/152 (86%) dogs that had an echocardiogram performed, 85/131 (65%) were structurally normal, with 40/85 (47%) structurally normal dogs having trace or mild atrioventricular valve regurgitation. Tricuspid valve dysplasia was the most commonly diagnosed congenital cardiac disease (n = 6). Myxomatous mitral valve disease (n = 12) and dilated cardiomyopathy (n = 13) were diagnosed at similar frequencies, though 92% of valve disease cases were mild. Only 48/152 (32%) Borzoi had a diagnostic electrocardiogram (ECG) and/or a Holter monitor for arrhythmia screening. Despite this, ventricular arrhythmias were identified during the entirety of the available cardiac evaluation including diagnostic ECG, contemporaneous ECG monitoring during the echocardiogram, and/or Holter monitor in 25/131 (19%) dogs in which an echocardiographic diagnosis was available. Of these 25 Borzoi, 76% had minimal or no structural cardiac disease identified, and five had a family history of sudden death. A sudden death outcome was reported in 3/55 (5%) Borzoi with long-term outcome data available. In conclusion, Borzoi commonly have trace or mild atrioventricular valve insufficiencies, and may develop ventricular arrhythmias and dilated cardiomyopathy.
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Angiotensin-converting enzyme inhibitors (ACEI) such as benazepril are commonly prescribed in both humans and dogs with heart disease to mitigate the renin-angiotensin-aldosterone system (RAAS); however, the dose-dependent effects of benazepril on comprehensive RAAS components remain unknown. In this study, nine purpose-bred healthy dogs received three different dosages of oral benazepril (0.125 mg/kg, 0.25 mg/kg, or 0.5 mg/kg) in a randomized crossover design following induction of RAAS activation by consuming a low-sodium diet. Blood samples were collected at serial time intervals after benazepril dosing to measure plasma benazeprilat (active metabolite of benazepril) and serum RAAS biomarkers. Blood pressure and echocardiogram were performed at baseline and after each benazepril administration. Time-weighted averages for RAAS biomarkers for 12 h post-dose and hemodynamic variables were compared between dosing groups using Wilcoxon rank-sum testing. Compared to the lowest dosage of benazepril (0.125 mg/kg), the highest dosage (0.5 mg/kg) resulted in lower time-weighted average values of angiotensin (Ang) II (- 38%, P = 0.004), Ang1-5 (- 53%, P = 0.001), ACE-S (surrogate for ACE activity; - 59%, P = 0.0002), and ALT-S (surrogate for alternative RAAS activity; - 22%, P = 0.004), and higher values of AngI (+ 78%, P = 0.014) and PRA-S (surrogate for plasma renin activity; + 58%, P = 0.040). There were no relevant differences between dosing groups for blood pressure or echocardiographic variables. Knowledge of dose-dependent alterations in biomarkers of the classical and alternative RAAS pathways could help inform clinical trials for dosage optimization in both dogs and humans.
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Inibidores da Enzima Conversora de Angiotensina , Sistema Renina-Angiotensina , Animais , Cães , Aldosterona/farmacologia , Angiotensina II/farmacologia , Inibidores da Enzima Conversora de Angiotensina/farmacologia , BiomarcadoresRESUMO
OBJECTIVE: To describe the clinical presentation and outcome in dogs diagnosed with Trypanosoma cruzi infection in nonendemic areas and to survey veterinary cardiologists in North America for Chagas disease awareness. ANIMALS: 12 client-owned dogs; 83 respondents from a veterinary cardiology listserv. PROCEDURES: A retrospective, multicenter medical records review to identify dogs diagnosed with American trypanosomiasis between December 2010 and December 2020. An anonymous online survey was conducted August 9 to 22, 2022. RESULTS: Diagnosis was made using indirect fluorescent antibody titer (n = 9), quantitative PCR assay (1), or postmortem histopathology (2). Time spent in Texas was < 1 year (n = 7) or 2 to 8 years (5). Time in nonendemic areas prior to diagnosis was < 1 year (n = 10) and > 3 years (2). Eleven had cardiac abnormalities. Of the 12 dogs, 5 had died unexpectedly (range, 1 to 108 days after diagnosis), 4 were still alive at last follow-up (range, 60 to 369 days after diagnosis), 2 were euthanized because of heart disease (1 and 98 days after diagnosis), and 1 was lost to follow-up. Survey results were obtained from 83 cardiologists in North America, of which the self-reported knowledge about Chagas disease was limited in 49% (41/83) and 69% (57/83) expressed interest in learning resources. CLINICAL RELEVANCE: Results highlight the potential for encountering dogs with T cruzi infection in nonendemic areas and need for raising awareness about Chagas disease in North America.
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Doença de Chagas , Doenças do Cão , Trypanosoma cruzi , Animais , Cães , Estudos Retrospectivos , Doença de Chagas/diagnóstico , Doença de Chagas/epidemiologia , Doença de Chagas/veterinária , Texas , Inquéritos e Questionários , Doenças do Cão/diagnóstico , Doenças do Cão/epidemiologiaRESUMO
BACKGROUND: Kidney injury (KI) has been documented in dogs treated with furosemide for left-sided congestive heart failure (CHF). HYPOTHESIS/OBJECTIVES: Determine risk factors for development of KI in furosemide-treated dogs and determine the effect of KI on survival. ANIMALS: Seventy-nine client-owned dogs receiving parenteral furosemide for CHF. METHODS: Serum creatinine (sCr) and electrolyte concentrations were determined during hospitalization and at first outpatient reevaluation to detect and stage KI (increase in sCr ≥0.3 mg/dL). Furosemide dosage administered between timepoints was calculated. Multivariable modeling was performed to identify predictors of KI and percent change in serum biochemistry results over time. RESULTS: Kidney injury was identified in 38/79 (48%) dogs and mostly occurred during hospitalization. Kidney injury was Grade I in 25 dogs, Grade II in 9 dogs, and Grade III in 4 dogs. Higher blood pressure was associated with acute KI during hospitalization (odds ratio, 1.03; 95% confidence interval [95% CI] 1.01-1.07; P = .03) whereas PO furosemide dosage was associated with KI after hospital discharge (odds ratio, 7.77; 95% CI, 2.05-68.6; P = .02). Baseline sCr and use of a furosemide continuous rate infusion were not associated with increased risk of KI. Kidney injury was not associated with long-term outcome. Of 13 dogs with Grade II-III KI, azotemia was reversible in 9 dogs, and 6 dogs survived >1 year after KI. CONCLUSIONS AND CLINICAL IMPORTANCE: In this cohort of dogs receiving parenteral furosemide for CHF, KI was common, mostly nonazotemic (Grade I), and did not impact survival.
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Injúria Renal Aguda , Doenças do Cão , Insuficiência Cardíaca , Cães , Animais , Furosemida/efeitos adversos , Diuréticos/efeitos adversos , Estudos Retrospectivos , Insuficiência Cardíaca/induzido quimicamente , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/veterinária , Rim , Fatores de Risco , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/veterinária , Injúria Renal Aguda/complicações , Doenças do Cão/induzido quimicamente , Doenças do Cão/tratamento farmacológicoRESUMO
BACKGROUND: Activity of the circulating renin-angiotensin-aldosterone system (RAAS) has not been comprehensively characterized in cats with systemic hypertension (SH) or cardiomyopathy (CM), and the effects of furosemide or amlodipine treatment on the RAAS have not been fully evaluated in cats. HYPOTHESIS/OBJECTIVES: To document RAAS activity in cats with SH or CM compared to healthy cats and determine how RAAS profiles change with furosemide or amlodipine treatment. ANIMALS: Sixty-six client-owned cats: 15 with SH (7 amlodipine-treated, 8 untreated), 17 with advanced CM (7 furosemide-treated, 10 not furosemide-treated), and 34 healthy cats. METHODS: Equilibrium concentrations of RAAS peptides and aldosterone were quantified in serum samples by liquid chromatography-mass spectrometry. Variables were compared between groups using Kruskal-Wallis analysis with post hoc Holms-corrected Dunn's testing. RESULTS: Compared with healthy cats, cats with CM had higher concentrations of angiotensin I, aldosterone, and plasma renin activity (all P < .01), and these differences remained significant (P < .03) after considering subgroups of untreated or furosemide-treated cats. Compared with healthy cats, untreated cats with SH showed no differences in RAAS biomarkers, whereas amlodipine-treated cats had higher concentrations of angiotensins I, II, III, IV, and 1-7, aldosterone, and plasma renin activity (all P < .03). Multivariable analysis determined that furosemide and amlodipine treatments were independent predictors of increased RAAS biomarker concentrations. CONCLUSIONS AND CLINICAL IMPORTANCE: Cats with CM had increased RAAS activity, whereas cats with untreated SH did not. Furosemide and amlodipine both led to nonspecific activation of both classical and alternative RAAS pathways in cats.
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Cardiomiopatias , Doenças do Gato , Hipertensão , Aldosterona , Anlodipino/farmacologia , Anlodipino/uso terapêutico , Animais , Biomarcadores , Cardiomiopatias/tratamento farmacológico , Cardiomiopatias/veterinária , Doenças do Gato/tratamento farmacológico , Gatos , Furosemida/farmacologia , Furosemida/uso terapêutico , Hipertensão/tratamento farmacológico , Hipertensão/veterinária , Renina , Sistema Renina-Angiotensina/fisiologiaRESUMO
Policy changes in response to the coronavirus disease 2019 (COVID-19) pandemic at Iowa State University College of Veterinary Medicine (ISU-CVM) included the administrative directive that fourth-year (VM4) clinical rotations immediately transition from in-person to virtual format. This article summarizes the efforts, successes, and challenges experienced by ISU-CVM clinical faculty during this transition. Numerous data sources were reviewed, including college records and announcements, faculty survey results, and student rotation evaluations. Data were explored using quantitative and qualitative methods. Between March and July 2020, 36 faculty from 15 different clinical services invested approximately 5,000 hours in delivering virtual content to 165 VM4 students from ISU-CVM and Caribbean veterinary schools. With departmental, college, and university assistance, faculty effectively used educational technologies (Zoom, Canvas, Echo360) and developed adaptive and innovative methods for virtual content delivery. Virtual VM4 rotations were collectively well received and appreciated by students, and student evaluation scores for virtual rotations were statistically equivalent to or higher than those for the corresponding in-person rotations in the preceding year. Although certain hands-on skills could not be adequately acquired in a virtual environment, students gained theoretical knowledge and case-based problem-solving skills in the online format. Faculty reported satisfaction with their adaptability and resilience in these challenging circumstances. These findings demonstrate that ISU-CVM clinical faculty invested substantial time and effort to transition in-person clinical rotations to virtual format during the early COVID-19 pandemic. This is particularly noteworthy given that many of these same faculty simultaneously served as essential personnel managing clinical cases in the university's teaching hospital.
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COVID-19 , Educação em Veterinária , Animais , COVID-19/epidemiologia , COVID-19/veterinária , Humanos , Iowa/epidemiologia , Pandemias , UniversidadesRESUMO
Scandium-47 (47Sc) is of high value for targeted radiotherapy and theranostics; we report a novel, cost-effective approach to produce high-purity 47Sc via photonuclear reactions with natural vanadium. Irradiation at 20 MeV photon end-point energy produces >99.998% pure 47Sc, while irradiation at 38 MeV produces 98.8 ± 1.6% pure 47Sc. Experimental data suggest producing greater than 100 mCi (3700 MBq) of 47Sc using this approach may be feasible. Future research into refinement and scale-up to support pre-clinical research is recommended.
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Focused cardiac ultrasound (FCU) is a useful point-of-care imaging tool to assess cardiovascular status in symptomatic dogs in the acute care setting. Unlike complete echocardiography, FCU is a time-sensitive examination involving a subset of targeted ultrasound views to identify severe cardiac abnormalities and is performed as part of an integrated thoracic ultrasound including interrogation of the pleural space and lungs. When integrated with other clinical information, FCU can be helpful in the diagnosis of left-sided and right-sided congestive heart failure, pericardial effusion and tamponade, and severe pulmonary hypertension, and can provide estimates of fluid responsiveness in hypotensive dogs.
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Doenças do Cão , Cardiopatias Congênitas , Insuficiência Cardíaca , Derrame Pericárdico , Animais , Doenças do Cão/diagnóstico por imagem , Cães , Ecocardiografia/veterinária , Cardiopatias Congênitas/veterinária , Insuficiência Cardíaca/veterinária , Derrame Pericárdico/diagnóstico por imagem , Derrame Pericárdico/veterináriaRESUMO
BACKGROUND: Angiotensin-converting enzyme inhibitors (ACEIs) are commonly prescribed in dogs, but the ideal dosage is unknown. HYPOTHESIS/OBJECTIVES: In dogs with cardiac disease, a dose-response relationship exists for ACEIs with respect to long-term outcome. ANIMALS: One hundred forty-four dogs with cardiac disease, 63 with current or prior congestive heart failure. METHODS: Retrospective medical record review. Cox proportional hazards models were used to determine variables associated with 2-year survival or survival from first-onset congestive heart failure (CHF). RESULTS: Median initial ACEI dosage was 0.84 (interquartile range [IQR], 0.56-0.98) mg/kg/day, and 108/144 (75%) of dogs received q12h dosing. No clinically relevant changes in renal function test results, serum electrolyte concentrations, or blood pressure occurred between initial prescription of ACEI and first reevaluation (median, 14 days later). In univariable analysis, higher ACEI dose was associated with increased survival from first-onset CHF (P = .005), and within the subgroup of dogs in CHF at the time of ACEI prescription, higher ACEI dose was associated with improved survival at 2 years (P = .04). In multivariable analysis, q12h dose frequency of ACEI (hazard ratio [HR], 0.30; 95% CI, 0.10-0.88; P = .03) and higher serum potassium concentration at visit 1 (HR, 0.39; 95% CI, 0.16-0.97; P = .04) were predictive of 2-year survival. The ACEIs were well-tolerated, with only 8/144 (5.6%) dogs having ACEI dose decreased or discontinued because of adverse effects. CONCLUSIONS AND CLINICAL IMPORTANCE: Twice daily dose frequency might optimize the cardioprotective benefit of ACEIs.
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Doenças do Cão , Insuficiência Cardíaca , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Animais , Doenças do Cão/tratamento farmacológico , Cães , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/veterinária , Potássio , Modelos de Riscos Proporcionais , Estudos RetrospectivosRESUMO
OBJECTIVES: To compare the use of curvilinear-array (microconvex) and phased-array transducers for ultrasonographic examination of the lungs in dogs. ANIMALS: 13 client-owned dogs with left-sided congestive heart failure. PROCEDURES: In a prospective methods comparison study, 24 ultrasonographic examinations of the lungs (4 sites/hemithorax) were performed with both curvilinear-array and phased-array transducers at 3 clinical time points. Two observers independently assessed the number of B lines (scored per site and in total), number of sites strongly positive for B lines (ie, those with > 3 B lines/site), and image quality (scored on a 5-point scale). Analyses included assessment of interobserver agreement with κ analysis, comparison of quality scores between transducers with mixed-effects modeling, and investigation of agreement and bias for B-line data and quality scores between transducers with Passing-Bablok regression. RESULTS: Interobserver agreement for total B-line scores and number of strong-positive sites was excellent (κ > 0.80) for both transducers. There was no evidence of analytic bias for the number of B lines or strong-positive sites between transducers. Interobserver agreement for image quality scores was moderate (κ, 0.498 and 0.517 for the curvilinear-array and phased-array transducers, respectively). Both observers consistently assigned higher-quality scores to curvilinear-array images than to phased-array images. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated both curvilinear-array (microconvex) and phased-array transducers can be used by experienced sonographers to obtain diagnostic ultrasonographic images of the lungs in dogs with acute or resolving left-sided congestive heart failure and suggested the former transducer may be preferred, particularly to aid identification of anatomic landmarks for orientation.
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Pulmão , Transdutores , Animais , Cães , Pulmão/diagnóstico por imagem , Estudos Prospectivos , Ultrassonografia/veterináriaRESUMO
INTRODUCTION: Ultrasonographic indices of the inferior vena cava are useful for predicting right heart filling pressures in people. OBJECTIVES: To determine whether ultrasonographic indices of caudal vena cava (CVC) differ between dogs with right-sided CHF (R-CHF), left-sided CHF (L-CHF), and noncardiac causes of cavitary effusion (NC). MATERIALS AND METHODS: 113 dogs diagnosed with R-CHF (n = 51), L-CHF (30), or NC effusion (32) were enrolled. Seventeen of the R-CHF dogs had pericardial effusion and tamponade. Focused ultrasound was performed prospectively to obtain 2-dimensional and M-mode subxiphoid measures of CVC maximal and minimal size (CVCmax and CVCmin), CVCmax indexed to aortic dimension (CVC:Ao), and CVC collapsibility index (CVC-CI). Variables were compared between study groups using Kruskal-Wallis and Dunn's-Bonferroni testing, and receiver operating characteristics curves were used to assess sensitivity and specificity. RESULTS: All sonographic CVC indices were significantly different between R-CHF and NC dogs (P < 0.001). Variables demonstrating the highest diagnostic accuracy for discriminating R-CHF versus NC were CVC-CI <33% in 2D (91% sensitive and 96% specific) and presence of hepatic venous distension (84% sensitive and 90% specific). L-CHF dogs had higher CVC:Ao and lower CVC-CI compared to NC dogs (P = 0.016 and P = 0.043 in 2D, respectively) but increased CVC-CI compared to the R-CHF group (P < 0.001). CONCLUSIONS: Ultrasonographic indices of CVC size and collapsibility differed between dogs with R-CHF compared to NC causes of cavitary effusions. Dogs with L-CHF have CVC measurements intermediate between R-CHF and NC dogs.
Assuntos
Insuficiência Cardíaca/diagnóstico , Veia Cava Inferior/diagnóstico por imagem , Animais , Cães , Feminino , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/veterinária , Masculino , Derrame Pericárdico/diagnóstico , Derrame Pericárdico/veterinária , Estudos Prospectivos , UltrassonografiaRESUMO
Aortic body tumors, specifically chemodectomas, are the second most common type of canine cardiac tumor; however, information about treatment is currently lacking. This study included dogs with a presumptive or definitive diagnosis of an aortic body chemodectoma that underwent treatment with toceranib phosphate. Cases were solicited via the American College of Veterinary Internal Medicine Cardiology, Internal Medicine, and Oncology listservs using an electronic survey. Cox multivariate analysis of factors potentially impacting survival time was completed. Twenty-seven (27) cases were included in analysis. The clinical benefit rate (complete remission, partial remission, or stable disease >10 weeks) was 89%. A median survival time of 478 days was found for those receiving toceranib alone (n = 14), which was not statistically different from those treated with additional modalities (521 days). No factors evaluated statistically impacted outcome. Further, prospective studies are warranted to evaluate the use of toceranib for the treatment of canine aortic body chemodectomas.