Volumetric quantification identifies some left atrial dilations undetected by left atrium:aorta ratio measurements: A prospective echocardiographic study in 155 Cavalier King Charles Spaniels with and without degenerative mitral valve disease.

INTRODUCTION: Degenerative mitral valve disease (DMVD) is the most common canine heart disease with a high predisposition in Cavalier King Charles Spaniels (CKCSs). Mitral regurgitation related to DMVD can lead to left atrial (LA) dilation, which is associated with survival time. Left-atrial-to-aortic (LA:Ao) ratio assessed by two-dimensional echocardiography is commonly used to evaluate LA size. The objectives of this prospective observational study were therefore 1) to compare different echocardiographic methods (i.e., monoplane and biplane Simpson's methods of discs (SMOD) and area-length methods (ALM)) in evaluating LA volume (LAvol) in CKCSs, 2) to assess LA volumes according to DMVD severity and, 3) compare the ability of LAvol and LA:Ao ratio to identify LA enlargement in CKCSs with subclinical DMVD (i.e., American College of Veterinary Internal Medicine (ACVIM) stage B). MATERIALS AND METHODS: 155 CKCSs, either healthy or affected by DMVD, were recruited. Variability and concordance between volumetric methods were evaluated. Values were analyzed according to 2019 ACVIM stages. RESULTS: All Lin's concordance correlation coefficients regarding intra- and inter-observer variability were considered as very good to excellent. Monoplane methods and ALM produced higher values of LAvol than biplane methods and SMOD, respectively. The upper limit of normal end-systolic LAvol/body weight (LASvol/BW) was defined as 0.90 mL/kg. Left atrial volumes significantly increased with ACVIM stages. Additionally, 37% of stage B1 CKCSs demonstrated LA enlargement using LASvol/BW assessment, with significantly lower LASvol/BW values in dogs with regurgitation fraction ≤30% than in others (p<0.01). CONCLUSION: In CKCSs, LAvol methods are not interchangeable. In ACVIM stage B CKCSs, LAvol quantification is more effective to detect LA enlargement than LA linear measurements.

Red blood cell abnormalities occur in dogs with congenital ventricular outflow tract obstruction.

OBJECTIVE: To document RBC abnormalities in dogs with congenital ventricular outflow tract obstruction. ANIMALS: 62 dogs with pulmonic stenosis (PS) or aortic stenosis (AS) and 20 control dogs were recruited. PROCEDURES: The proportions of RBCs that were schistocytes, acanthocytes, and keratocytes were assessed. Complete blood cell counts were performed. Tested variables included hemoglobin concentration, hematocrit, and erythrocyte count. RESULTS: Median (interquartile range [IQR]) peak systolic Doppler-derived trans-stenotic pressure gradient (∆P) values were 161 mm Hg (108 to 215 mm Hg) and 134 mm Hg (125 to 165 mm Hg) for dogs with PS and AS, respectively. Hematologic abnormalities were detected in most dogs with AS or PS (54/62 [87%]) versus 8/20 [40%] in control dogs, with schistocytes found in 40 of 62 (65%; median, 0.1% RBCs; IQR, 0% to 0.3%), acanthocytes in 29 of 62 (47%; median, 0.3% RBCs; IQR, 0% to 0.9%), keratocytes in 39 of 62 (63%; median, 0% RBCs; IQR, 0% to 0.2%), and hemolytic anemia in 4 dogs with PS. No significant association was identified between these abnormalities and ∆P. However, 3 of 4 dogs with anemia had a ∆P > 200 mm Hg (range, 242 to 340 mm Hg). The dog with the highest ∆P value also had the most severe anemia and schistocytosis, and both resolved after balloon valvuloplasty. CLINICAL RELEVANCE: Poikilocytosis is common in dogs with congenital ventricular outflow tract obstruction, with anemia only observed in few dogs with high ∆P values.

Tolerance of torasemide in cats with congestive heart failure: a retrospective study on 21 cases (2016-2019).

BACKGROUND: In dogs with congestive heart failure (CHF), the efficacy of torasemide, a loop diuretic, has been demonstrated. However, unlike in dogs and humans little has been described about the use of torasemide in the cat with spontaneous CHF. The objectives of this retrospective study were therefore to describe the therapeutic use of oral torasemide in cats with spontaneous CHF, document its potential adverse effects while reporting the clinical course of this feline population following torasemide administration in addition to standard medical therapy. RESULTS: Medical records of 21 client-owned cats with CHF (median age = 10.6 years [interquartile range (IQR) = 6.5-11.2]) receiving torasemide were reviewed. Data collected included torasemide dosages, other concurrent medications, physical examination features, echocardiographic data, and potential adverse effects during follow-up. A survival analysis was performed to estimate the time from diagnosis to cardiac death. Dyspnea related to CHF was identified in all cats (pleural effusion [8/21], pulmonary edema [5/21] or both [8/21]), associated with ascites in 4/21 cats. The CHF cause was determined by echocardiography in all cats: hypertrophic (n = 10), restrictive (n = 6), arrhythmogenic right ventricular (n = 3), dilated (n = 1) cardiomyopathies, and aortic valve abnormality (n = 1). At initiation, median torasemide dosage was 0.21 mg/kg [IQR = 0.17-0.23] q24h. Clinical signs declined in most cats (20/21) during the first 2 weeks with no remarkable adverse events. Median survival time after torasemide prescription was 182 days [IQR = 46-330]. A contemporary control group including 54 cats with CHF, receiving furosemide as sole loop diuretic treatment was compared with the study group. Median (IQR) survival time of cats in the control group was not significatively different (p = 0.962) from that of the torasemide group, i.e., 148 days (9-364), although the torasemide group included significantly more cats with recurrent episodes of CHF (52%) that the control group (19%). CONCLUSIONS: This case series demonstrates that torasemide can be used in cats with spontaneous CHF. This therapeutic interest needs to be confirmed by prospective clinical trials.

Long-term incidence and risk of noncardiovascular and all-cause mortality in apparently healthy cats and cats with preclinical hypertrophic cardiomyopathy.

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.

Clinical, epidemiological and echocardiographic features and prognostic factors in cats with restrictive cardiomyopathy: A retrospective study of 92 cases (2001-2015).

BACKGROUND: Restrictive cardiomyopathy (RCM) is a common primary cardiomyopathy of cats. However, little information is available regarding prognostic variables in large populations of cats with RCM. OBJECTIVES: To characterize the epidemiological, clinical, and echocardiographic features of cats with RCM and to document their survival times and risk factors for cardiac death (CD). ANIMALS: Ninety-two cats with RCM. METHODS: Retrospective study. Diagnosis of RCM was based on echocardiographic and Doppler criteria. Median survival time to CD and adjusted hazard ratios (HR) were estimated by the Kaplan-Meier method and multivariate Cox models, respectively. RESULTS: The feline population (median age [interquartile range], 8.6 years [4.1-12.4]; body weight, 4.0 kg [3.3-4.7]) included 83 cats (90%) with the myocardial RCM form and 9 (10%) with the endomyocardial fibrosis RCM form. Most RCM cats (64/92, 70%) were symptomatic at the time of diagnosis, with dyspnea related to congestive heart failure in 57 of 64 cats (89%). The median survival time of the 69 cats with the myocardial RCM form and available follow-up was 667 days (range, 2-3710 days) considering CD. Independent of age, biatrial enlargement, and arrhythmias, increase of the left atrium (LA)-to-aorta (Ao) ratio (hazard ration [HR], 2.5 per 0.5-unit increase; 95% confidence interval [CI], 1.5-4.2; P < .001) and presence of severe LA enlargement (end-diastolic LA : Ao ≥2; HR, 3.4; 95% CI, 1.3-8.7; P = .01) were significantly associated with shorter time to CD. CONCLUSIONS AND CLINICAL IMPORTANCE: Cardiac death is common in RCM cats, and LA enlargement seems independently associated with decreased survival time in these cats.

International collaborative study to assess cardiovascular risk and evaluate long-term health in cats with preclinical hypertrophic cardiomyopathy and apparently healthy cats: The REVEAL Study.

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.

Epidemiological, clinical, and echocardiographic features and survival times of dogs and cats with tetralogy of Fallot: 31 cases (2003-2014).

OBJECTIVE To characterize the epidemiological, clinical, and echocardiographic features of dogs and cats with tetralogy of Fallot (TOF) and determine their survival times. DESIGN Retrospective case series. ANIMALS 15 dogs and 16 cats with a diagnosis of TOF as determined via echocardiography. PROCEDURES Medical records of dogs and cats were reviewed to extract information on signalment, clinical status at the time of TOF diagnosis, echocardiographic findings, and any outcome data. RESULTS The most common canine breeds were terrier types (n = 7). Most animals (28/31 [90%]) had clinical signs of TOF at the time of diagnosis, including cyanosis (16/31 [52%]). Pulmonic stenosis was characterized by a variable systolic Doppler-derived pressure gradient (median [range], 108 mm Hg [26 to 255 mm Hg]). Most ventricular septal defects were large, with a median (range) ratio of the diameter of the ventricular septal defect to that of the aorta of 0.60 (0.18 to 1.15). Median age at cardiac-related death was 23.4 months, with no significant difference between dogs and cats. Median survival time from TOF diagnosis to cardiac-related death was briefer for animals with no or low-grade heart murmur (3.4 months) than for those with higher-grade heart murmur (16.4 months). After adjustment for age and sex, having a lack of or a low- to mild-grade systolic heart murmur was significantly associated with a briefer survival time. CONCLUSIONS AND CLINICAL RELEVANCE With a few exceptions, cardiac-related death occurred predominantly in young adult dogs and cats with TOF, and most animals had severe clinical signs at the time of TOF diagnosis.

PREVALENCE OF VALVULAR REGURGITATIONS IN CLINICALLY HEALTHY CAPTIVE LEOPARDS AND CHEETAHS: A PROSPECTIVE STUDY FROM THE WILDLIFE CARDIOLOGY (WLC) GROUP (2008-2013).

The purpose of this prospective study was to evaluate transthoracic echocardiograms from clinically healthy large felids for the presence of valvular regurgitations (VR). Physiologic VR commonly occur in normal dogs and cats, but the percentage of large felids with VR has not been previously reported. During a 5-yr study period (2008-2013), 28 healthy animals were evaluated under general anesthesia: 16 cheetahs (Acinonyx jubatus soemmeringuii) with a mean age of 1.5±0.8 yr (range 0.7-3.5 yr), 5 Amur leopards (Panthera pardus orientalis), 1 snow leopard (Uncia uncia), and 6 clouded leopards (Neofelis nebulosa). For this study, all the leopards were gathered in one so-called "leopards group" with a mean age of 2.8±3.4 yr (range 0.3-10.7 yr). All valves observed in each view were examined for evidence of regurgitant jets and turbulent blood flow using the color-flow Doppler mode. Valves were also examined for structural changes. Mitral valve and aortic cusp abnormalities were considered to be of congenital origin. Mitral valve lesions led to mitral insufficiency in all the felids. Aortic cusp abnormalities led to aortic regurgitation in 94% of the cheetahs and 67% of the leopards. Leopards showed a predominance of early systolic mitral regurgitations, whereas all the mitral regurgitation jets in cheetahs were holosystolic. Tricuspid regurgitation was found in 81% of the cheetahs and in 50% of the leopards, whereas pulmonic regurgitation was detected in 44% of the cheetahs and 33% of the leopards. Interestingly, none of these tricuspid and pulmonic regurgitations were associated with two-dimensional structural valve abnormalities, thus suggesting their physiologic origin, as described in humans, cats, and dogs. In conclusion, subclinical valvular diseases are common in apparently healthy leopards and cheetahs. Longitudinal follow-up of affected animals is therefore required to assess their clinical outcome.

Surgical Treatment of Cor Triatriatum Sinister in a Cat Under Cardiopulmonary Bypass.

OBJECTIVE: To report the surgical repair of cor triatriatum sinister (CTS) incorporating heart-beating cardiopulmonary bypass (CPB) in a cat. STUDY DESIGN: Clinical case report. ANIMAL: Fourteen-month-old, 5.9-kg male castrated Maine Coon cat. MATERIALS AND METHODS: The cat had a 3 month history of inappetance, weight loss, and recurrent pulmonary edema. CTS with severe systolic pulmonary arterial (SPA) hypertension (124 mm Hg) was diagnosed by 2D echocardiography, color flow and continuous wave Doppler modes, and left atrial and pulmonary angiography. Surgery was performed through a left intercostal thoracotomy. CPB was initiated and the heart was kept beating. The left atrial appendage was opened and the intra-atrial membrane was excised. RESULTS: After 48 hours, the cat was doing well. Reduced SPA pressure (52 mm Hg) with decreased right heart enlargement was observed on ultrasound examination and the cat was discharged 6 days after surgery with oral antibiotics for 10 days, aspirin, and furosemide. Four months after surgery, the cat presented with increased activity and weight gain and was completely asymptomatic. Transthoracic echocardiography showed a marked improvement of all echo-Doppler variables with disappearance of SPA hypertension (24 mm Hg). Four years after surgery, the cat was still doing well with no recurrence of clinical signs despite the lack of medical treatment. CONCLUSION: CTS in the cat may be successfully treated by surgery facilitated by use of CPB leading to early and long-term substantial improvement in clinical status and cardiac function. CTS can safely be repaired under CPB in cats.

Signalment, clinical features, echocardiographic findings, and outcome of dogs and cats with ventricular septal defects: 109 cases (1992-2013).

OBJECTIVE: To determine the signalment, clinical features, echocardiographic findings, and outcome of dogs and cats with ventricular septal defects (VSDs). DESIGN: Retrospective case series. ANIMALS: 56 dogs and 53 cats with VSDs. PROCEDURES: Medical records of dogs and cats with VSDs diagnosed by means of conventional and Doppler echocardiography were reviewed. Signalment, clinical status, echocardiographic findings, and outcome data were recorded. Variables of interest were analyzed for the study population and subgroups according to species and clinical status. RESULTS: VSDs were isolated (ie, solitary defects) in 53 of 109 (48.6%) patients. Most (82/109 [75.2%]) VSDs were membranous or perimembranous. Terriers and French Bulldogs were commonly represented canine breeds. Most isolated VSDs were subclinical (43/53 [81%]) and had a pulmonary-to-systemic flow ratio < 1. 5 (24/32 [75%]). The VSD diameter and VSD-to-aortic diameter ratio were significantly correlated with pulmonary-to-systemic flow ratio in dogs (r = 0.529 and r = 0.689, respectively) and in cats (r = 0.713 and r = 0.829, respectively). One dog underwent open surgical repair for an isolated VSD and was excluded from survival analysis. Of the remaining animals with isolated VSDs for which data were available (37/52 [71%]), no subclinically affected animals developed signs after initial diagnosis, and median age at death from all causes was 12 years. CONCLUSIONS AND CLINICAL RELEVANCE: Most dogs and cats with isolated VSDs had a long survival time; few had clinical signs at diagnosis, and none with follow-up developed clinical signs after diagnosis.

Basal plasma concentrations of routine variables and packed cell volume in clinically healthy adult small-sized dogs: effect of breed, body weight, age, and gender, and establishment of reference intervals.

BACKGROUND: Plasma variables may be affected by breed or body weight (BW). Small-sized dogs are very common, but no specific reference intervals (RI) are used. OBJECTIVES: The primary objective of this prospective study was to assess the potential effect of breed, BW, age, and sex on routine plasma analytes and packed cell volume (PCV) in small-sized dogs. A secondary objective was to establish RI in this small-sized population. METHODS: Blood was sampled under standardized conditions from healthy dogs. PCV and 15 routine plasma variables were measured at the same laboratory. Effects of breed, BW, age, and sex were tested using a general linear model. The procedure recommended by the Clinical and Laboratory Standards Institute was used to establish RI. RESULTS: In this study, 154 healthy dogs from 7 breeds were prospectively included. Although a significant effect of breed, BW, sex, or age was evidenced for most variables (except plasma sodium, phosphates, and triglycerides), it was considered as clinically irrelevant. More strikingly, the percentage of values in the reference sample group under the lower limit of the laboratory's RI ranged from 3.8% to 76.6% for 9 variables, and those higher than the upper limit of the laboratory's RI ranged from 4.5% to 9.7% for 7 variables. For example, the RI for creatinine in small-sized dogs was 45-90 µmol/L (vs 54-144 µmol/L for the general dog population). CONCLUSION: Specific RI should be considered for PCV and selected plasma variables in small-sized dogs.

Cardiovascular effects of dietary salt intake in aged healthy cats: a 2-year prospective randomized, blinded, and controlled study.

High salt dry expanded diets are commercially available for cats to increase water intake and urine volume, as part of the prevention or treatment of naturally occurring urinary stone formation (calcium oxalates and struvites). However, chronic high salt intake may have potential cardiovascular adverse effects in both humans, especially in aging individuals, and several animal models. The objective of this prospective, randomized, blinded, and controlled study was to assess the long-term cardiovascular effects of high salt intake in healthy aged cats. Twenty healthy neutered cats (10.1 ± 2.4 years) were randomly allocated into 2 matched groups. One group was fed a high salt diet (3.1 g/Mcal sodium, 5.5 g/Mcal chloride) and the other group a control diet of same composition except for salt content (1.0 g/Mcal sodium, 2.2 g/Mcal chloride). Clinical examination, systolic and diastolic arterial blood pressure measurements, standard transthoracic echocardiography and conventional Doppler examinations were repeatedly performed on non-sedated cats by trained observers before and over 24 months after diet implementation. Radial and longitudinal velocities of the left ventricular free wall and the interventricular septum were also assessed in systole and diastole using 2-dimensional color tissue Doppler imaging. Statistics were performed using a general linear model. No significant effect of dietary salt intake was observed on systolic and diastolic arterial blood pressure values. Out of the 33 tested imaging variables, the only one affected by dietary salt intake was the radial early on late diastolic velocity ratio assessed in the endocardium of the left ventricular free wall, statistically lower in the high salt diet group at 12 months only (P = 0.044). In conclusion, in this study involving healthy aged cats, chronic high dietary salt intake was not associated with an increased risk of systemic arterial hypertension and myocardial dysfunction, as observed in some elderly people, salt-sensitive patients and animal models.

Echocardiography and conventional Doppler examination in clinically healthy adult Cavalier King Charles Spaniels: effect of body weight, age, and gender, and establishment of reference intervals.

OBJECTIVES: The objectives of this study were (1) to assess the potential effect of body weight (BW), age, and gender on the most commonly used echocardiographic and conventional Doppler variables in a large population of healthy Cavalier King Charles Spaniels (CKCS), and (2) to establish the corresponding reference intervals (RI). ANIMALS: 134 healthy adult CKCS. METHODS: Ultrasound examinations were performed by trained observers in awake dogs. M-mode variables included left ventricular (LV) end-diastolic and end-systolic diameters, LV free wall and interventricular septal thicknesses at end-diastole and end-systole, and LV fractional shortening (FS%). The left atrium (LA) and aortic (Ao) diameters were measured using a 2D method, and the LA/Ao was calculated. Pulsed-wave Doppler variables included peak systolic aortic and pulmonary flow velocities, mitral E and A waves, and E/A ratio. Effects of BW, age, and gender on these 15 variables were tested using a general linear model, and RIs were determined by applying the statistical procedures recommended by the Clinical and Laboratory Standards Institute. RESULTS: A significant BW effect was observed for all variables, except LA/Ao, FS%, and mitral E/A ratio. A significant but negligible effect of gender and age was also observed for 5/15 and 4/15 of the tested variables, respectively. Only the BW effect on M-mode variables was considered as clinically relevant and the corresponding regression-based RIs were calculated. CONCLUSIONS: Body weight should be taken into account when interpreting echocardiographic values in CKCS, except for LA/Ao, FS%, and mitral E/A ratio.

Basal plasma concentrations of N-terminal pro-B-type natriuretic peptide in clinically healthy adult small size dogs: effect of body weight, age, gender and breed, and reference intervals.

Plasma NT-proBNP has previously been evaluated in dogs with degenerative mitral valve disease (DMVD). However, reference intervals (RI) established according to the Clinical Laboratory and Standards Institute (CLSI) recommendations have never been provided. The objectives of this prospective study were to assess effects of breed, body weight, age, and sex on plasma NT-proBNP, and to establish RI according to CLSI for this biomarker in a large population of dogs predisposed to DMVD. 183 Healthy small-sized dogs from 7 breeds were included. Assays were performed by ELISA. Effects of covariates were tested using a general linear model. Although a sex effect was demonstrated (P=0.01), no significant effect of breed, body weight or age was shown. The proposed RI was 157-2842 pmol/L. 7% of dogs had plasma NT-proBNP >2617 pmol/L, and were considered as outliers despite normal cardiovascular examination. In conclusion, plasma NT-proBNP may be high in a few healthy small-sized dogs.

Prospective echocardiographic and tissue Doppler screening of a large Sphynx cat population: reference ranges, heart disease prevalence and genetic aspects.

OBJECTIVES: (1) To investigate heart morphology and function using echocardiography and tissue Doppler imaging (TDI), (2) to determine heart disease prevalence and characteristics, and (3) to assess potential genetic features in a population of Sphynx cats presented for cardiovascular screening. ANIMALS: A total of 147 echocardiographic examinations, including 33 follow-ups, were performed by trained observers on 114 Sphynx cats of different ages (2.62 ± 1.93 years [0.5-10.0]) from 2004 to 2011. METHODS: Sphynx cats underwent a physical examination, conventional echocardiography, and, if possible, two-dimensional color TDI. RESULTS: Conventional echocardiographic findings included 75/114 normal (65.8%) and 39/114 (34.2%) abnormal examinations with a diagnosis of either congenital heart diseases (n = 16) or hypertrophic cardiomyopathy (HCM, n = 23). In adult healthy cats, a significant body weight effect was observed for several echocardiographic variables, including end-diastolic left ventricular (LV) free wall (P < 0.01), interventricular septum (P < 0.001), and LV diameter (P < 0.001). Mitral valve dysplasia (MVD) was observed as a single or associated defect in 15/16 cats with congenital heart diseases. A significant increase in HCM prevalence (P < 0.001) was observed according to age. The pedigree analysis of a large family (n = 81) suggested an autosomal dominant mode of inheritance with incomplete penetrance for HCM. CONCLUSIONS: Body weight should be taken into account when interpreting values of diastolic myocardial wall thicknesses in Sphynx cats. Additionally, HCM and MVD are two relatively common heart diseases in this feline breed. More pedigree data are required to confirm the inheritance pattern of HCM at the breed level.

Within-day and between-day variability of transthoracic anatomic M-mode echocardiography in the awake bottlenose dolphin (Tursiops truncatus).

The use of transthoracic echocardiography in dolphins has been limited so far owing to technical and anatomical specificities. Anatomic M-mode (AMM) is a postprocessing echocardiographic technique generating M-mode studies from two-dimensional (2D) cineloops independently of the ultrasound beam orientation. The aim of the present study was to determine the within-day (repeatability) and between-day (reproducibility) variability of AMM echocardiography in awake healthy bottlenose dolphins (BN, Tursiops truncatus). Four adult BN trained to lie in left recumbency at the water surface were involved in the protocol. A total of 96 echocardiographic examinations were performed on 4 different days by a trained observer examining each BN 6 times per day. Video clips of 2D left parasternal long-axis views showing the left ventricle (LV) ventrally and the aortic root dorsally were recorded at each examination and analyzed for AMM measurements in a random order. A general linear model was used to determine the within-day and between-day coefficients of variation (CV). All examinations were interpretable allowing calculation of 10 AMM variables (i.e., end-diastolic and end-systolic ventral and dorsal LV myocardial wall thicknesses as well as LV and aortic diameters, mean aortic diameter, and LV shortening fraction). Most within- and between-day CV values (18/20) were <15%, the lowest being observed for the end-diastolic LV diameter (1.6%). In conclusion, AMM provides a simple non-invasive evaluation of heart morphology and function in the awake BN with good repeatability and reproducibility of the measurements. Further studies are required to determine the corresponding reference intervals.

Relationship between paradoxical breathing and pleural diseases in dyspneic dogs and cats: 389 cases (2001-2009).

OBJECTIVE: To determine the strength of the relationship between paradoxical breathing (PB) and spontaneous pleural diseases in dyspneic dogs and cats. DESIGN: Cross-sectional study. ANIMALS: Dogs (n = 195) and cats (194) with a recorded diagnosis of dyspnea examined at the National Veterinary Schools of Alfort and Toulouse (France) between January 2001 and October 2009. PROCEDURES: Dogs and cats were divided into 2 groups according to the presence or absence of PB. Stratified analysis by species was performed. Signalment of affected animals and occurrence of PB were recorded. The relationship between PB and pleural diseases among dyspneic dogs and cats was analyzed. RESULTS: A strong relationship between PB and pleural diseases was highlighted in multivariate analysis (dogs, OR = 12.6 and 95% confidence interval = 4.6 to 31.2; cats, OR = 14.1 and 95% confidence interval = 6.0 to 33.5). Paradoxical breathing prevalence among dyspneic dogs and cats was 27% and 64%, respectively. Occurrence of pleural diseases in dyspneic animals with and without PB was 49% and 9% in dogs and 66% and 13% in cats, respectively. The sensitivity and specificity of PB as a predictor of pleural diseases were 0.67 and 0.83 in dyspneic dogs and 0.90 and 0.58 in dyspneic cats, respectively. The positive and negative predictive values of PB were 0.49 and 0.91 in dyspneic dogs and 0.66 and 0.87 in dyspneic cats, respectively. Age, sex, feline breeds, and canine morphotypes in patients with PB were not significantly different from those of other dyspneic animals. CONCLUSIONS AND CLINICAL RELEVANCE: PB was strongly associated with pleural diseases in dyspneic dogs and cats. The presence of this clinical sign should prompt small animal practitioners to implement appropriate emergency procedures and guide their diagnostic strategy.

Echoguided closed commissurotomy for mitral valve stenosis in a dog.

Surgical treatment of mitral stenosis (MS) usually consists of open mitral commissurotomy (MC) or percutaneous balloon MC, which require a cardiopulmonary bypass or transseptal approach, respectively. We describe here the first surgical management of congenital MS in a dog using a less invasive procedure, a surgical closed MC under direct echo guidance. A 5-year-old female Cairn terrier was referred for ascites, weakness, and marked exercise intolerance for 2 months, which was refractory to medical treatment. Diagnosis of severe MS associated with atrial fibrillation (AF) was confirmed by echo-Doppler examination and electrocardiography. Poor response to medical treatment suggested a corrective procedure on the valve was indicated. However, due to the cost and high mortality rate associated with cardiopulmonary bypass, a hybrid MC was recommended. A standard left intercostal thoracotomy was performed and three balloon valvuloplasty catheters of differing diameters were sequentially inserted through the left atrium under direct echo guidance. Transesophageal echocardiography revealed a 62% reduction in the pressure half-time compared to the pre-procedure. Thirteen months after surgery the dog is still doing well with resolution of ascites and a marked improvement of most echo-Doppler variables.

Prevalence of the MYBPC3-A31P mutation in a large European feline population and association with hypertrophic cardiomyopathy in the Maine Coon breed.

OBJECTIVES: The MYBPC3-A31P mutation has been identified in the USA in a colony of Maine Coon cats with an autosomal dominant hypertrophic cardiomyopathy (HCM). The objectives of this prospective study were: 1) to evaluate the prevalence of this mutation in a large feline population from Europe; 2) to compare these data with the prevalence of HCM in the Maine Coon breed. ANIMALS AND METHODS: 1) 3757 cats from different breeds including 2744 Maine Coon cats were screened for the mutation. 2) 164/2744 Maine Coon cats were subjected to echocardiography (Echo-Group, mean age = 2.6 years [0.3-11.5]). RESULTS: 1) In the whole study population, the mutation was only found in Maine Coon cats (prevalence = 41.5%), except for one British Longhair cat. 2) 55/164 (34%) cats from the Echo-Group carried the mutation while only 12/164 (7%; 5/48 heterozygous, 5/7 homozygous mutated, 2/109 homozygous wild-type cats) showed HCM. MYBPC3-A31P was associated with a significant increased risk of HCM (relative risk = 9.91). CONCLUSION: The MYBPC3-A31P mutation is highly prevalent in Maine Coon cats in Europe and appears to be breed specific with potential marginal events. Young unaffected mutated cats and affected homozygous wild-type cats illustrate the phenotypic and etiological heterogeneity of feline HCM, as demonstrated in humans.