Thin and hypokinetic myocardial segments in cats with cardiomyopathy.

INTRODUCTION/OBJECTIVES: Thin and hypokinetic myocardial segments (THyMS) represent adverse ventricular (LV) remodeling in human hypertrophic cardiomyopathy. We describe the echocardiographic features and outcome in cats with THyMS, and in a subpopulation, the echocardiographic phenotype before LV wall thinning was detected (pre-THyMS). ANIMALS: Eighty client-owned cats. MATERIALS AND METHODS: Retrospective multicenter study. Clinical records were searched for cats with THyMS, defined as LV segment(s) with end-diastolic wall thickness (LVWT) <3 mm and hypokinesis in the presence of ≥one LV segment(s) with LVWT >4 mm and normal wall motion. When available, echocardiograms pre-THyMS were assessed. Survival time was defined as time from first presentation with THyMS to death. RESULTS: Mean thickest LV wall segment (MaxLVWT) was 6.1 mm (95% CI 5.8-6.4 mm) and thinnest (MinLVWT) was 1.7 mm (95% CI 1.6-1.9 mm). The LV free wall was affected in 74%, apex in 13% and septum in 5%. Most cats (85%) presented with heart failure and/or arterial thromboembolism. Median circulating troponin I concentration was 1.4 ng/mL ([range 0.07-180 ng/mL]). Prior echocardiography results were available for 13/80 cats, a mean of 2.5 years pre-THyMS. In segments subsequently undergoing thinning, initial MaxLVWT measured 6.7 mm (95% CI 5.8-7.7 mm) vs. 1.9 mm (95% CI 1.5-2.4 mm) at last echocardiogram (P<0.0001). Survival data were available for 56/80 cats, median survival time after diagnosing THyMS was 153 days (95% CI 83-223 days). Cardiac histopathology in one cat revealed that THyMS was associated with severe transmural scarring. CONCLUSIONS: Cats with THyMS had advanced cardiomyopathy and a poor prognosis.

The next heartbeat: Creating dynamic and histographic Poincaré plots for the assessment of cardiac rhythms.

The rhythm of the heart is not a stationary phenomenon, and therefore, incorporation of the dynamic Poincaré plot and tachogram provides additional diagnostic information to complement and expand waveform (P-QRST) analyses from the electrocardiogram. Although pattern assessment of the Poincaré plot and tachogram can provide an appraisal for normal and abnormal rhythms and serve as a potential means for machine-learned rhythm diagnoses, time-selected windows of beat-to-beat variability permit more detailed examination. As such, expanded criteria for rhythm diagnoses, identification of arrhythmic triggers, global appreciation of rhythm changes, and recognition of patterns that provoke mechanistic questions may be gleaned from the use of the methods reviewed in this report. More specifically, these methods demonstrate that limitations exist in the reliance on traditional measures of heart rate variability in the dog due to the non-linear beat-to-beat rhythm of sinus arrhythmia in the species. Behavior of arrhythmias based on coupling intervals, repeating patterns, preceding triggers of beat-to-beat variability, and circumstantial evidence of atrioventricular nodal conduction during atrial flutter and fibrillation are a few examples of discovery founded in these techniques. The open access website, The Next Heartbeat (https://thenextheartbeat.com/), permits anyone to implement these methods in the assessment of long-term electrocardiographic examinations (Holter monitoring) so that, as yet to be revealed, features of the beating heart through time may be discovered.

The use of Amplatzer vascular plug II in 32 consecutive dogs for transvenous occlusion of patent ductus arteriosus.

OBJECTIVES: To describe the use of the Amplatzer vascular plug II (AVPII) for transvenous occlusion of patent ductus arteriosus in a non-selective population of dogs, with a focus on the surgical technique, short term outcome and associated complications. ANIMALS, MATERIALS AND METHODS: Retrospective study. Records of thirty-two consecutive dogs treated for a left-to-right shunting patent ductus arteriosus with the AVPII were reviewed. RESULTS: Ductal occlusion with an AVPII occlusion device was attempted in 32 dogs weighing 1.1-53.8 kg. Transvenous occlusion was successful in 30 dogs. One dog required a transarterial approach for occlusion. One dog died during catheterisation of the right heart but prior to transductal catheterisation. Mean ductal ampulla diameter was 7.9 mm (range, 4.1-15.4 mm) and median size of deployed devices was 10 mm (range 4-20 mm). Mean device to ampulla ratio was 1.34 ± 0.15. Device was positioned in situ with no residual flow on follow-up echocardiographic assessment (> one month) in all dogs where deployment was attempted. Occlusion success rate was 96.9% and mortality rate was 3.1%. Four dogs (13.3%) demonstrated minor complications, with none having long-term significance. CONCLUSIONS: The use of AVPII device via a transvenous approach is a feasible and effective method for occlusion of a left-to-right shunting patent ductus arteriosus in dogs of a wide range of weight. The method described may complement existing catheter-based occlusion methods.

Segmental septal dyskinesia associated with an accessory pathway and preexcitation in two Golden Retriever dogs.

Ventricular preexcitation secondary to anterograde conduction through an accessory pathway was diagnosed in two Golden Retriever dogs. Both dogs demonstrated similar segmental myocardial thinning and systolic dyskinesia of the basal interventricular wall on echocardiography. These changes are widely recognised in people with ventricular preexcitation but have not been previously described in dogs. Ventricular preexcitation should be considered as a potential cause for segmental wall motion abnormalities in these two dogs.

Supraventricular tachycardia in 23 cats; comparison with 21 cats with atrial fibrillation (2004-2014).

INTRODUCTION: Supraventricular tachycardia (SVT) has not been well described in cats. The aim of this study was to describe the signalment, clinical findings, and outcome for cats with SVT versus cats with atrial fibrillation (AF). ANIMALS: Forty-four client owned cats are included in the study. 23 cats with SVT and 21 with AF. METHODS: This is a retrospective study. Clinical characteristics were compared between groups using a two-sample t-test or Mann-Whitney U test. Kaplan-Meier survival curves were generated to assess for impact of rhythm diagnosis, presence of ventricular arrhythmia, left atrial diameter, heart rate and congestive heart failure (CHF) status on cardiac death. Differences in survival between groups were compared using Mantel-Cox logrank comparison of Kaplan-Meier survival curves. RESULTS: Cats with supraventricular arrhythmias most commonly presented with respiratory distress (10 of 44 cats). Cats with AF had a slower median heart rate (220 [range: 180-260 beats per minute (bpm)] compared with cats with SVT (300 [range: 150-380] bpm, p < 0.001). All cats with AF had structural heart disease, whereas 4 cats with SVT had no structural abnormalities. Left atrial diameter was significantly larger in cats with AF (23.7 (16.2-40.1) mm compared with 19.1 (12.8-31.4) mm in SVT cats; p = 0.02). Median survival was 58 days (1-780) in cats with AF and 259 days (2-2295) in cats with SVT (p = 0.1). Cats with signs of CHF had a shorter survival time (p = 0.001). CONCLUSIONS: Most cats with AF or SVT have advanced structural heart disease. Some cats with SVT had structurally normal hearts, suggesting that SVT in cats is not always a consequence of atrial enlargement.

Clarification and confocal imaging of the nonhuman primate placental micro-anatomy.

Geometry of the placental villous vasculature is a key determinant of maternal-fetal nutrient exchange for optimal fetal growth. Recent advances in tissue clarification techniques allow for deep high-resolution imaging with confocal microscopy; however, the methodology lacks a signal:noise ratio of sufficient magnitude to allow for quantitative analysis. Thus, we sought to develop a reproducible method to investigate the 3D vasculature of the nonhuman primate placenta for subsequent data analysis. Fresh placental tissue was dissected, formalin fixed, clarified using a modified Visikol® protocol and immunolabeled for CD31 (fetal endothelium) and cytokeratin-7 (villous trophoblast) for confocal imaging of the microanatomy. We present a detailed clarification and staining protocol augmented for imaging of nonhuman primate placental tissue. The image stacks generated by this refined staining method and our data acquisition parameters can be analyzed quantitatively to provide insights regarding the villous and vascular micro-anatomy of the placenta.

Phenotypic description of cardiac findings in a population of Dogue de Bordeaux with an emphasis on atrial fibrillation.

The aim of this study was to describe the clinical phenotype of Dogue de Bordeaux (DdB) referred for cardiac investigation, with particular reference to the prevalence of atrial fibrillation and associated features. Review of canine medical records of two United Kingdom veterinary referral hospitals identified 64 DdB with available echocardiographic and electrocardiographic (ECG)/Holter data. Atrial fibrillation was documented in 25 (39%) dogs and supraventricular tachycardia was recorded in five (7.8%) dogs. In a subset of 34 dogs, excluding congenital heart disease (n=17), presence of a cardiac mass (n=7) and non-cardiac neoplasia (n=6), 19 (56%) dogs had atrial fibrillation, with a median heart rate of 200 beats per min (bpm) on presentation. Atrial fibrillation was inconsistently associated with cardiac chamber remodelling, but was frequently associated with systolic dysfunction (13/19, 68.4%) and right sided atrial or ventricular dilatation (14/19, 73.7%) in dogs with atrial fibrillation in this subset. No dogs in this subset had right sided atrial or ventricular dilatation in the absence of supraventricular arrhythmia or systolic dysfunction. The absence of structural heart disease in some dogs with supraventricular arrhythmias suggests that an underlying primary arrhythmic process might be responsible for initiating remodelling, although a primary cardiomyopathy cannot be ruled out.

Surgical treatment of pulmonic stenosis in dogs under cardiopulmonary bypass: outcome in nine dogs.

OBJECTIVES: To describe the outcome for nine dogs with pulmonic stenosis treated by open patch grafting using expanded polytetrafluoroethylene under cardiopulmonary bypass. MATERIALS AND METHODS: Data were collected from the hospital records of all dogs that had undergone right ventricular outflow tract grafting with an expanded polytetrafluoroethylene patch under cardiopulmonary bypass between 2006 and 2012 for the treatment of pulmonic stenosis. Echocardiographic images were reviewed and the pressure gradient across the right ventricular outflow tract re-measured. Owners of dogs still alive at the time of writing were invited to return to the hospital for reassessment. RESULTS: Nine dogs met the inclusion criteria. Median pressure gradient preoperatively was 118 mmHg, (range 102 to 259 mmHg) reducing to a median of 20 mmHg (range 7 to 53 mmHg) at 48 hours postoperatively and 14 mmHg (range 10 to 70 mmHg), with a median percentage reduction of 89% (range 41 to 94%) at long-term follow-up. Eight of nine dogs survived surgery, with six of nine surviving to hospital discharge. Two dogs were still alive over 6 and 8 years postoperatively. No long-term deaths were believed to be attributable to pulmonic stenosis. CLINICAL SIGNIFICANCE: Expanded polytetrafluoroethylene patch grafting of the right ventricular outflow tract for treatment of severe pulmonic stenosis in dogs is feasible and can be an effective method to reduce the severity of right ventricular outflow tract obstruction.

Outcome of bioprosthetic valve replacement in dogs with tricuspid valve dysplasia.

OBJECTIVES: To describe the short-term and long-term outcome in dogs with tricuspid valve dysplasia undergoing tricuspid valve replacement under cardiopulmonary bypass. METHODS: Data were collected from the hospital records of all dogs that had undergone tricuspid valve replacement under cardiopulmonary bypass between 2006 and 2012. Dogs were considered candidates for tricuspid valve replacement if they had severe tricuspid valve regurgitation associated with clinical signs of cardiac compromise. RESULTS: Nine dogs of six different breeds were presented. Median age was 13 months (range 7 to 61 months), median weight 26·5 kg (range 9·7 to 59 kg). Eight bovine pericardial valves and one porcine aortic valve were used. One non-fatal intraoperative complication occurred. Complications during hospitalisation occurred in six dogs, four of which were fatal. Of the five dogs discharged, one presented dead due to haemothorax after minor trauma seven days later. The four remaining dogs survived a median of 533 days; all of these dogs received a bovine pericardial valve. CLINICAL SIGNIFICANCE: Based on our results, tricuspid valve replacement with bovine or porcine prosthetic valves is associated with a high incidence of complications.

Television food advertisement exposure and FTO rs9939609 genotype in relation to excess consumption in children.

BACKGROUND/OBJECTIVE: Exposure to food advertisements may cue overeating among children, especially among those genetically predisposed to respond to food cues. We aimed to assess how television food advertisements affect eating in the absence of hunger among children in a randomized trial. We hypothesized that the fat mass and obesity-associated gene (FTO) rs9939609 single-nucleotide polymorphism would modify the effect of food advertisements. SUBJECTS/METHODS: In this randomized experiment, 200 children aged 9-10 years were served a standardized lunch and then shown a 34-min television show embedded with either food or toy advertisements. Children were provided with snack food to consume ad libitum while watching the show and we measured caloric intake. Children were genotyped for rs9939609 and analyses were conducted in the overall sample and stratified by genotype. A formal test for interaction of the food advertisement effect on consumption by rs9939609 was conducted. RESULTS: About 172 unrelated participants were included in this analysis. Children consumed on average 453 (s.d.=185) kcals during lunch and 482 (s.d.=274) kcals during the experimental exposure. Children who viewed food advertisements consumed an average of 48 kcals (95% confidence interval: 10, 85; P=0.01) more of a recently advertised food than those who viewed toy advertisements. There was a statistically significant interaction between genotype and food advertisement condition (P for interaction=0.02), where the difference in consumption of a recently advertised food related to food advertisement exposure increased linearly with each additional FTO risk allele, even after controlling for body mass index percentile. CONCLUSIONS: Food advertisement exposure was associated with greater caloric consumption of a recently advertised food, and this effect was modified by an FTO genotype. Future research is needed to understand the neurological mechanism underlying these associations.

Room temperature housing results in premature cancellous bone loss in growing female mice: implications for the mouse as a preclinical model for age-related bone loss.

UNLABELLED: Room temperature housing (22 °C) results in premature cancellous bone loss in female mice. The bone loss was prevented by housing mice at thermoneutral temperature (32 °C). Thermogenesis differs markedly between mice and humans and mild cold stress induced by standard room temperature housing may introduce an unrecognized confounding variable into preclinical studies. INTRODUCTION: Female mice are often used as preclinical models for osteoporosis but, in contrast to humans, mice exhibit cancellous bone loss during growth. Mice are routinely housed at room temperature (18-23 °C), a strategy that exaggerates physiological differences in thermoregulation between mice (obligatory daily heterotherms) and humans (homeotherms). The purpose of this investigation was to assess whether housing female mice at thermoneutral (temperature range where the basal rate of energy production is at equilibrium with heat loss) alters bone growth, turnover and microarchitecture. METHODS: Growing (4-week-old) female C57BL/6J and C3H/HeJ mice were housed at either 22 or 32 °C for up to 18 weeks. RESULTS: C57BL/6J mice housed at 22 °C experienced a 62 % cancellous bone loss from the distal femur metaphysis during the interval from 8 to 18 weeks of age and lesser bone loss from the distal femur epiphysis, whereas cancellous and cortical bone mass in 32 °C-housed mice were unchanged or increased. The impact of thermoneutral housing on cancellous bone was not limited to C57BL/6J mice as C3H/HeJ mice exhibited a similar skeletal response. The beneficial effects of thermoneutral housing on cancellous bone were associated with decreased Ucp1 gene expression in brown adipose tissue, increased bone marrow adiposity, higher rates of bone formation, higher expression levels of osteogenic genes and locally decreased bone resorption. CONCLUSIONS: Housing female mice at 22 °C resulted in premature cancellous bone loss. Failure to account for species differences in thermoregulation may seriously confound interpretation of studies utilizing mice as preclinical models for osteoporosis.

Differentiation of Cardiac from Noncardiac Pleural Effusions in Cats using Second-Generation Quantitative and Point-of-Care NT-proBNP Measurements.

BACKGROUND: Pleural effusion is a common cause of dyspnea in cats. N-terminal pro-B-type natriuretic peptide (NT-proBNP) measurement, using a first-generation quantitative ELISA, in plasma and pleural fluid differentiates cardiac from noncardiac causes of pleural effusion. HYPOTHESIS/OBJECTIVES: To determine whether NT-proBNP measurements using second-generation quantitative ELISA and point-of-care (POC) tests in plasma and pleural fluid distinguish cardiac from noncardiac pleural effusions and how results compare to the first-generation ELISA. ANIMALS: Thirty-eight cats (US cohort) and 40 cats (UK cohort) presenting with cardiogenic or noncardiogenic pleural effusion. METHODS: Prospective cohort study. Twenty-one and 17 cats in the US cohort, and 22 and 18 cats in the UK cohort were classified as having cardiac or noncardiac pleural effusion, respectively. NT-proBNP concentrations in paired plasma and pleural fluid samples were measured using second-generation ELISA and POC assays. RESULTS: The second-generation ELISA differentiated cardiac from noncardiac pleural effusion with good diagnostic accuracy (plasma: sensitivity, 95.2%, specificity, 82.4%; pleural fluid: sensitivity, 100%, specificity, 76.5%). NT-proBNP concentrations were greater in pleural fluid (719 pmol/L (134-1500)) than plasma (678 pmol/L (61-1500), P = 0.003), resulting in different cut-off values depending on the sample type. The POC test had good sensitivity (95.2%) and specificity (87.5%) when using plasma samples. In pleural fluid samples, the POC test had good sensitivity (100%) but low specificity (64.7%). Diagnostic accuracy was similar between first- and second-generation ELISA assays. CONCLUSIONS AND CLINICAL IMPORTANCE: Measurement of NT-proBNP using a quantitative ELISA in plasma and pleural fluid or POC test in plasma, but not pleural fluid, distinguishes cardiac from noncardiac causes of pleural effusion in cats.

Assessment of mitral regurgitation in dogs: comparison of results of echocardiography with magnetic resonance imaging.

OBJECTIVES: Echocardiography is used routinely to assess mitral regurgitation severity, but echocardiographic measures of mitral regurgitation in dogs have not been compared with other quantitative methods. The study aim was to compare echocardiographic measures of mitral regurgitation with cardiac magnetic resonance imaging-derived mitral regurgitant fraction in small-breed dogs. METHODS: Dogs with myxomatous mitral valve disease scheduled for magnetic resonance imaging assessment of neurological disease were recruited. Correlations were tested between cardiac magnetic resonance imaging-derived mitral regurgitant fraction and the following echocardiographic measures: vena contracta/aortic diameter, transmitral E-wave velocity, amplitude of mitral prolapse/aortic diameter, diastolic left ventricular diameter:aortic diameter, left atrium:aortic diameter, mitral regurgitation jet area ratio and regurgitant fraction calculated using the proximal isovelocity surface area method. RESULTS: Measurement of cardiac magnetic resonance imaging-derived mitral regurgitant fraction was attempted in 21 dogs. Twelve consecutive, complete studies were obtained and 10 dogs were included in the final analysis: vena contracta/aortic diameter (r = 0 · 89, p = 0 · 001) and E-wave velocity (r = 0 · 86, p = 0 · 001) had the strongest correlations with cardiac magnetic resonance imaging-derived mitral regurgitant fraction. E velocity had superior repeatability and could be measured in all dogs. The presence of multiple jets precluded vena contracta/aortic diameter measurement in one dog. CLINICAL SIGNIFICANCE: Measurement of cardiac magnetic resonance imaging-derived mitral regurgitant fraction is feasible but technically demanding. The echocardiographic measures that correlated most closely with cardiac magnetic resonance imaging-derived mitral regurgitant fraction were vena contracta/aortic diameter and E-wave velocity.

Differentiating between feline pleural effusions of cardiac and non-cardiac origin using pleural fluid NT-proBNP concentrations.

OBJECTIVE: To assess whether pleural fluid and urine amino terminal proB-type natriuretic peptide (NT-proBNP) can distinguish cardiac from non-cardiac causes of pleural effusion. METHODS: Blood, urine and pleural fluid were prospectively collected from cats presenting with pleural effusion categorised as cardiac or non-cardiac in origin. NT-ProBNP concentrations were measured using a feline-specific enzyme-linked immunosorbent assay. Groups were statistically compared and receiver operating characteristic curves constructed to determine cut-offs to distinguish cardiac from non-cardiac pleural effusion in plasma, pleural fluid and urine. RESULTS: Forty cats with pleural effusion (22 cardiac and 18 non-cardiac) were studied. NT-proBNP concentrations in plasma and pleural fluid were strongly correlated. Plasma (P<0·001) and pleural fluid (P<0·001) NT-proBNP concentrations and urinary NT-proBNT/creatinine ratios (P=0·035) were significantly higher in the cardiac group. After receiver operating characteristic curve analysis a plasma NT-proBNP cut-off of 214·3 pmol/mL was suggested [sensitivity=86·4% (95% CI: 66·7 to 95·3%), specificity=88·9% (95% CI: 67·2 to 96·9%)] and a pleural fluid NT-proBNP cut-off of 322·3 pmol/mL was suggested [sensitivity=100% (95% CI: 85·1 to 100%), specificity=94·4% (95% CI: 74·2 to 99·0%)]. No cut-off with adequate sensitivity and specificity for urinary NT-proBNP/creatinine ratios was suggested. CLINICAL SIGNIFICANCE: Measurement of NT-proBNP in pleural fluid distinguishes cardiac from non-cardiac causes of pleural effusion in cats.

[Smoking in movies and established smoking in adolescence]. / Rauchen in Filmen und Etablierung des Rauchens im Jugendalter.

AIM: The aim of this study was to examine whether smoking in movies can predict established smoking in adolescence. METHODS: A longitudinal study was conducted over a period of 13 months with 4112 German students. Adolescents' exposure to smoking in movies was assessed by asking each student to indicate which film he or she had seen from a unique list of 50 movies, which was randomly selected for each individual survey from a sample of 398 popular contemporary movies. We calculated exposure to movie smoking for each respondent by summing the number of smoking occurrences for each movie that the respondent reported seeing. RESULTS: At follow-up, a total of 272 young people had smoked more than 100 cigarettes during their lifetime. While 2.1% of the young people with the lowest exposure to movie smoking initiated established smoking, 13.4% of the group with the highest exposure to movie smoking initiated established smoking. The adjusted relative risk of initiation of established smoking was 2.05 times higher in the group with the highest movie smoking exposure compared to the group with the lowest exposure (95% confidence interval: 1.25-3.35). CONCLUSION: Our data indicate that smoking in movies can be regarded as an independent risk factor for the initiation of established smoking in adolescence.

Comparing the effects of entertainment media and tobacco marketing on youth smoking.

OBJECTIVES: To examine the concurrent effects of exposure to movie smoking and tobacco marketing receptivity on adolescent smoking onset and progression. METHODS: Cross-sectional study of 4524 northern New England adolescents aged 10-14 in 1999 with longitudinal follow-up of 2603 baseline never-smokers. Cross-sectional outcomes included ever tried smoking and higher level of lifetime smoking among 784 experimenters. The longitudinal outcome was onset of smoking among baseline never-smokers two years later. Movie smoking exposure was modelled as four population quartiles, tobacco marketing receptivity included two levels-having a favourite tobacco advert and wanting/owning tobacco promotional items. All analyses controlled for sociodemographics, other social influences, personality characteristics of the adolescent and parenting style. RESULTS: In the full cross-sectional sample, 17.5% had tried smoking; both exposure to movie smoking and receptivity to tobacco marketing were associated with having tried smoking. Among experimental smokers, the majority (64%) were receptive to tobacco marketing, which had a multivariate association with higher level of lifetime smoking (movie smoking did not). In the longitudinal study 9.5% of baseline never-smokers tried smoking at follow-up. Fewer never-smokers (18.5%) were receptive to tobacco marketing. Movie smoking had a multivariate association with trying smoking (receptivity to tobacco marketing did not). CONCLUSIONS: The results suggest separate roles for entertainment media and tobacco marketing on adolescent smoking. Both exposures deserve equal emphasis from a policy standpoint.