PubMed Health⌕ Search

Biomedical subjects

M Henroteaux

Publications and source records attributed to M Henroteaux.

At least 19 recordsLinked to original sources
PubMed2001

Usefulness of dobutamine stress tests for detection of cardiac abnormalities in dogs with experimentally induced early left ventricular dysfunction.

OBJECTIVE: To determine whether dobutamine stress tests (DST) can be used to detect cardiac dysfunction in dogs with early left ventricular dysfunction (ELVD) induced by rapid right ventricular pacing (RRVP). ANIMALS: 7 adult male Beagles. PROCEDURE: A pacemaker was surgically implanted in each dog at the level of the right ventricular apex. Electrocardiography, Doppler sphygmomanometry, and Doppler echocardiography were performed before and during a DST prior to activation of the pacemaker and every 3 to 4 days during the period of RRVP. Dobutamine stress tests were performed by infusing dobutamine at incremental dosages ranging from 12.5 to 42.5 microg/kg of body weight/min. RESULTS: Clinical signs of congestive heart failure were not observed during the pacing period. However, all dogs developed ELVD associated with significant changes in values for most Doppler echocardiographic variables obtained prior to DST Adverse cardiac effects were not detected during DST. Most Doppler echocardiographic indices of cardiac function were significantly altered in response to dobutamine infusion during the pacing period, compared with prepacing values. However, a dobutamine-induced 2-fold increase in cardiac output was maintained. CONCLUSIONS AND CLINICAL RELEVANCE: Dobutamine stress tests can be safely performed in dogs with experimentally induced ELVD. Dobutamine stress tests may be a sensitive, noninvasive diagnostic method, complementary to standard clinical examinations, for detection of early cardiac dysfunction in dogs asymptomatic for dilated cardiomyopathy.

Animals↗
PubMed2001

Metabolic and structural abnormalities in dogs with early left ventricular dysfunction induced by incessant tachycardia.

OBJECTIVE: To assess morphologic and metabolic abnormalities in dogs with early left ventricular dysfunction (ELVD) induced by rapid right ventricular pacing (RRVP). ANIMALS: 7 Beagles. PROCEDURE: Plasma carnitine concentrations were measured before and after development of ELVD induced by RRVP. At the same times, transvenous endomyocardial biopsy was performed, and specimens were submitted for determination of myocardial carnitine concentrations and histologic, morphometric, and ultrastructural examination. RESULTS: In 4 dogs in which baseline plasma total carnitine concentration was normal, RRVP induced a decrease in myocardial total and free carnitine concentrations and an increase in myocardial esterified carnitine concentration. In 3 dogs in which baseline plasma total carnitine concentration was low, plasma and myocardial carnitine concentrations were unchanged after pacing. Structural changes associated with pacing included perinuclear vacuolization in 3 dogs. Morphometric analyses indicated there was a decrease in myofiber cross-sectional diameter and area following pacing. Electron microscopy revealed changes in myofibrils and mitochondria following pacing. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that moderate to severe alterations in myocyte cytoarchitecture are present in dogs with ELVD induced by RRVP and that in dogs with normal plasma carnitine concentrations, myocardial carnitine deficiency may be a biochemical marker of ELVD. Results also indicated that transvenous endomyocardial biopsy can be used to evaluate biochemical and structural myocardial changes in dogs with cardiac disease.

Animals↗
PubMed2000

Use of ciliogenesis in the diagnosis of primary ciliary dyskinesia in a dog.

Primary ciliary dyskinesia is a congenital condition that may cause chronic rhinitis and bronchopneumonia. Primary ciliary dyskinesia may be diagnosed by induction of ciliogenesis by use of in vitro cell culture. Induction of ciliogenesis allows for differentiation between primary and secondary ciliary dyskinesia.

Animals↗
PubMed2000

Juvenile nephropathy in a boxer, a rottweiler, a collie and an Irish wolfhound.

Juvenile nephropathy was diagnosed in a Boxer, a Rottweiler, a Collie and an Irish Wolfhound dog, each presenting with signs compatible with chronic renal failure. The diagnosis in each case was based on the presence of persistence of poorly differentiated tissue (immature glomeruli and/or tubules, persistent mesenchyme) on histopathologic examination. Although juvenile nephropathy has been reported in many breeds of dog, this is the first report of the condition in the Collie and the Irish Wolfhound and only the second description in the Boxer and the Rottweiler. The possibility of an inherited origin of the condition in these four breeds is at present unknown.

Age Factors↗
PubMed1999

Doppler echocardiographic study of left and right ventricular function during dobutamine stress testing in conscious healthy dogs.

OBJECTIVE: To evaluate left and right ventricular filling and ejection performances by use of Doppler echocardiography in healthy, conscious dogs submitted to dobutamine stress testing. ANIMALS: 10 unsedated, healthy adult Beagles. PROCEDURE: Doppler echocardiography was performed during cardiac stress testing on each dog twice at 24-hour intervals. Dobutamine was infused in 10 micrograms/kg of body weight/min incremental dosages, from 12.5 to 42.5 micrograms/kg/min. Duration of each step was 15 minutes. Doppler measurements were recorded at baseline and at each stage of dobutamine infusion, whereas aortic diameter was measured at baseline and at peak dosage by use of two-dimensional echocardiography. RESULTS: Dobutamine infusion induced a significant increase in velocity time integrals and in peak flow velocities at the aortic, pulmonic, mitral, and tricuspid valves. Acceleration time-to-deceleration time ratio at the aortic wave also was increased significantly. On the other hand, ejection time, acceleration time, and deceleration time at the aortic and pulmonic valves and peak flow velocity of the E wave-to-peak flow velocity of the A wave ratio at the mitral and tricuspid valves decreased significantly during the test. The acceleration time-to-deceleration time ratio at the pulmonic wave was unchanged. A significant, progressive increase in cardiac index also was observed during dobutamine infusion, with a maximal increase of 104% from baseline. This was mediated initially by an increase in stroke index and, at higher dosages, by an increase in heart rate. CONCLUSIONS AND CLINICAL RELEVANCE: Doppler echocardiography performed during dobutamine stress testing may be a reliable method of assessing myocardial function in dogs with cardiovascular disease.

Animals↗
PubMed1998

Laryngeal rhabdomyoma in a golden retriever.

A three-year-old male golden retriever had had progressive dyspnoea, exercise intolerance, stridor, and a modified bark for five months. A mass 2 cm in diameter was present dorsal to the right side of the larynx. Histological examination revealed cross-striations in some elongated cells, consistent with a diagnosis of rhabdomyoma, a diagnosis which was confirmed by positive immunohistochemical staining for myoglobin and desmin. The mass could not be removed without total laryngectomy and a permanent tracheostomy and the dog was euthanased.

Animals↗
PubMed1998

Physiologic response to dobutamine infusion during cardiac stress testing of dogs.

OBJECTIVE: To evaluate response of various cardiovascular variables after administration of incremental doses of dobutamine in healthy conscious dogs, using standardized dobutamine stress echocardiography (DSE). ANIMALS: 8 healthy dogs. PROCEDURE: A DSE was performed twice on each dog within 24 hours. Dobutamine was infused at a rate of 12.5 to 42.5 microg/kg/min, using incremental increases of 10 microg/kg/min. Doppler sphygmomanometry, electrocardiography, and echocardiography were performed. Left ventricular size, global ventricular performance, and left ventricular systolic myocardial function were measured by means of echocardiography. RESULTS: At the highest dosage, dobutamine induced an increase of 20+/-3% and 109+/-12% in systolic blood pressure and cardiac index, respectively. The latter was associated with a significant increase in heart rate and stroke index. Fractional shortening of the left ventricle, fractional thickening of the left ventricular free wall and interventricular septum, ejection fraction, and mean velocity of fiber shortening had a progressive and significant increase during dobutamine infusion. Preejection period and left ventricular ejection time had a progressive and significative decrease during the stress test. CONCLUSIONS: The technique used was feasable, safe, and repeatable in healthy conscious dogs. Control values were determined. CLINICAL RELEVANCE: Data for these healthy dogs might be useful for comparison with results obtained from dogs with known or suspected cardiovascular disease.

Animals↗
PubMed1996

Cardiac performance in conscious healthy dogs during dobutamine infusion.

The aim of this study was to determine the cardiac performance of conscious healthy dogs during stimulation with dobutamine. Eight healthy unsedated beagle dogs were used. Cardiac output was measured by the thermodilution technique and blood pressures by extravascular pressure transducers. Dobutamine challenge at a dosage ranging from 27.5 to 50 micrograms kg-1 min-1 induced a significant rise in cardiac power index (CPI), cardiac index (CI), stroke index (SI) and heart rate (HR) and a significant decrease in pulmonary vascular resistance (PVR) and systemic vascular resistance (SVR). The highest CPI was 2.05 times greater than its basal resting value. The CI was primarily responsible for this increase in CPI. The SI and HR contributed approximately 55 per cent and 45 per cent respectively of the maximal increase in CI.

Analysis of Variance↗
PubMed1995

Closantel intoxication in a dog.

A case of overdosage with closantel, a salicynalide derivative, in a dog is described. The dog received 6 times the recommended dosage. Closantel induced optic neuritis, retinal degeneration, partial deafness, hepatotoxicosis and myopathy. Only the blindness was irreversible. The therapy included albumin administration to reduce the acute toxicity of closantel.

Albumins↗
PubMed1994

Acute polymyopathy after carbamate poisoning in a dog.

The acute polymyopathy in a seven-year-old German shepherd dog was attributed to the muscular hypertonia, tremors and seizures which developed during the acute phase of carbamate poisoning. After two days of generalised muscular rigidity, the dog adopted a characteristic fetal position which could be explained by the imbalance between the injuries to the extensor and flexor muscles. The polymyopathy resolved gradually over the course of a week.

Acute Disease↗
PubMed1975

Feline infectious peritonitis. Proteins of plasma and ascitic fluid.

Electrophoreses of sera, plasma and ascitic fluids of cats with natural or experimental infectious peritonitis show important modifications. Special stainings of electrophoreses and chromatographic and immunoelectrophoretic technics characterized some of the modified proteins. In the experimental disease, fibrinogen, haptoglobin, transferrin, and probably orosomucoid are increased; in the natural disease, in addition to these modifications, the gamma-globulins are strongly increased; the immunoglobulins found in the often abundant ascitic fluid belong to the IgG class. Increased proteins such as fibrinogen, haptoglobin and orosomucoid and decreased albumin are aspecific aspects of inflammatory processes, whereas hypergammaglobulinemia appears in the course of immunological response. The rapid evolution of the experimental disease explains the fact that immunoglobulins do not increase.

Alpha-Globulins↗
PubMedDate not supplied

Effects of dobutamine on isovolumic and ejection phase indices of cardiac contractility in conscious healthy dogs.

The aim of this study was to determine cardiac contractility using indices derived from cardiac catheterisation in conscious healthy dogs during dobutamine infusion. Eight dogs were studied. An ECG was recorded together with left ventricular pressure and volume which were measured using a conductance catheter with an integrated microtip pressure sensor. Eight indices of left ventricular systolic performance were derived from these records. Measurements were realised under basal conditions and during an incremental dobutamine challenge. The maximal rate of rise in ventricular pressure (max dP/dt), max dP/dt divided by the developed pressure and the mean systolic ejection rate were the most sensitive indices to detect dobutamine induced changes in contractility with maximal percentage changes of 122+/-11 per cent, 130+/-7 per cent and 102+/-24 per cent respectively. Ejection fraction increased significantly during dobutamine infusion (maximal percentage change of 43+/-9 per cent) whereas the pre-ejection period (PEP) and the left ventricular ejection time (LVET) decreased significantly (maximal percentage change of -41+/-2 per cent and -28+/-3 per cent respectively). All these six indices were significantly correlated with each other. Conversely, the ratio PEP/LVET and the LVET corrected for heart rate dependency showed a maximal percentage change of only -10+/-1 per cent and -16+/-7 per cent, respectively, during the dobutamine infusion and were not significantly correlated with the other contractility indices. This study demonstrated the feasibility of the conductance method to determine cardiac contractility in conscious healthy dogs submitted to a pharmacological stress testing and provides control values for eight indices of left ventricular contractility during dobutamine infusion at increasing dosages.

Animals↗
PubMedDate not supplied

Eosinophilic bronchopneumopathy in dogs.

Eosinophilic bronchopneumopathy was diagnosed in 23 young dogs. Clinical signs included cough, gagging, and retching in all dogs, dyspnea in 21 dogs (91%), and nasal discharge in 12 dogs (52%). The most common radiographic findings were a moderate to severe bronchointerstitial pattern (68%, 13 of 19 dogs). Bronchoscopic findings included the presence of abundant yellow-green mucus or mucopurulent material (70%, 16 of 23 dogs) and severe mucosal thickening with an irregular or polypoid appearance (52%, 12 of 23 dogs), with partial airway closure during expiration in 3 dogs (13%). Peripheral blood eosinophilia was noted in 14 of 23 dogs (61%). Inflammatory cells in brush or bronchoalveolar lavage fluid cytologic preparations comprised more than 50% eosinophils in 14 of 23 dogs (61%), and 20-50% eosinophils in 6 dogs (26%). Eosinophilic infiltration of the bronchial mucosa was observed in biopsies from 19 dogs and was graded as mild (37%, 7 dogs), moderate (32%, 6 dogs), or severe (32%, 6 dogs). The mean serum immunoglobulin A concentration was almost double that of a population of 20 healthy dogs of various breeds. Oral glucocorticoids were administered on alternate days with progressive tapering of the dose; the dosage at maintenance varied between 0.1 and 1.0 mg/kg every other day. No relationship was found between the duration of clinical signs and the maintenance dosage or the cytologic and histopathologic grades.

Animals↗