Left atrial volume and function in dogs with naturally occurring myxomatous mitral valve disease.

OBJECTIVE: Myxomatous mitral valve disease (MMVD) induces progressive left atrial (LA) enlargement. The LA modulates left ventricular filling and performance through its reservoir, conduit, and contractile function. Assessment of LA size and function may provide valuable information on the level of cardiac compensation. Left atrial function in dogs with naturally occurring MMVD remains largely unexplored. The objective of this study was to evaluate LA volume and function in dogs with naturally occurring MMVD. ANIMALS: This prospective study included 205 client-owned dogs of different breeds, 114 healthy dogs, and 91 dogs with MMVD of different disease severities. METHODS: Using two-dimensional echocardiography, the biplane area-length method was applied to assess LA volume and calculate volumetric indices of LA reservoir, conduit, and contractile function. RESULTS: Left atrial volume and LA stroke volume increased, whereas LA reservoir and contractile function decreased with increasing disease severity. A maximal LA volume <2.25mL/kg was the optimal cut off identified for excluding congestive heart failure in dogs with chronic MMVD with a sensitivity of 96% and a specificity of 100%. An active LA emptying fraction <24% and/or a LA expansion index <126% were suggestive of congestive heart failure in dogs with chronic MMVD with a sensitivity of 77% and a specificity of 89% and a sensitivity of 82% and a specificity of 82%, respectively. CONCLUSION: Dogs with MMVD appear to have larger LA volumes with poorer LA function. Deteriorating LA function, characterized by a decreasing reservoir and active contractile function, was evident in dogs with MMVD with increasing disease severity.

Repeated measurements of blood lactate concentration as a prognostic marker in horses with acute colitis evaluated with classification and regression trees (CART) and random forest analysis.

The objective of this study was to investigate the prognostic value of single and repeated measurements of blood l-lactate (Lac) and ionised calcium (iCa) concentrations, packed cell volume (PCV) and plasma total protein (TP) concentration in horses with acute colitis. A total of 66 adult horses admitted with acute colitis (<24 h) to a referral hospital in the 2002-2011 period were included. The prognostic value of Lac, iCa, PCV and TP recorded at admission and 6 h post admission was analysed with univariate analysis, logistic regression, classification and regression trees, as well as random forest analysis. Ponies and Icelandic horses made up 59% of the population, whilst the remaining 41% were horses. Blood lactate concentration at admission was the only individual parameter significantly associated with probability of survival to discharge (P < 0.001). In a training sample, a Lac cut-off value of 7 mmol/L had a sensitivity of 0.66 and a specificity of 0.92 in predicting survival. In independent test data, the sensitivity was 0.69 and the specificity was 0.76. At the observed survival rate (38%), the optimal decision tree identified horses as non-survivors when the Lac at admission was ≥4.3 mmol/L and the Lac 6 h post admission stayed at >2 mmol/L (sensitivity, 0.72; specificity, 0.8). In conclusion, blood lactate concentration measured at admission and repeated 6 h later aided the prognostic evaluation of horses with acute colitis in this population with a very high mortality rate. This should allow clinicians to give a more reliable prognosis for the horse.

Comparison of four echocardiographic methods to determine left atrial size in dogs.

OBJECTIVES: To compare a linear and three volume-based two-dimensional echocardiographic methods for measuring LA size: left atrium to aorta ratio (LA/Ao ratio), biplane area-length, biplane modified Simpson and monoplane area-length. ANIMALS: One hundred seventy-six client-owned dogs of different breeds, 88 healthy dogs and 88 dogs with myxomatous mitral valve disease of different disease severity. METHODS: The left apical four- and two-chamber views were used to measure LA volumes. The right parasternal short-axis view at the level of the heart base was used to measure the LA/Ao ratio. RESULTS: The biplane area-length method yielded 2.8% larger values than those of the biplane modified Simpson method, consistent across the full range of LA volumes. The monoplane area-length method derived on average 5.8% larger values of LA volume than the biplane area-length method. The difference between these two methods was most pronounced at larger LA volumes. The relation between the LA/Ao ratio and LA volume was curvilinear and with increasing LA size these two methods derived very dissimilar values. CONCLUSIONS: All methods showed good feasibility and reproducibility, with the volume-based methods having the most favourable intra- and inter-observer variabilities. The LA/Ao ratio underestimates at higher values of LA size compared to the biplane area-length method. LA volume methods may be superior to the LA/Ao ratio in quantification of LA size. The biplane area-length method and biplane modified Simpson method can be used interchangeably. The monoplane area-length measurement may be used as a quick and reliable method for assessment of LA size in clinical practice.

Physical activity and the association with fatigue and sleep in Danish patients with rheumatoid arthritis.

The aim of this study was to examine physical activity behavior in patients with rheumatoid arthritis and to identify potential correlates of regular physical activity including fatigue, sleep, pain, physical function and disease activity. A total of 443 patients were recruited from a rheumatology outpatient clinic and included in this cross-sectional study. Physical activity was assessed by a four-class questionnaire, in addition to the Physical Activity Scale. Other instruments included the Multidimensional Fatigue Inventory (MFI), the Pittsburgh Sleep Quality Index and the Health Assessment Questionnaire. Disease activity was obtained from a nationwide clinical database. Of the included patients, 80 % were female and mean age was 60 (range 21-88 years). Hereof, 22 % (n = 96) were regularly physically active, and 78 % (n = 349) were mainly sedentary or having a low level of physical activity. An inverse univariate association was found between moderate to vigorous physical activity, and fatigue (MFI mental, MFI activity, MFI physical and MFI general), sleep, diabetes, depression, pain, patient global assessment, HAQ and disease activity. The multivariate prediction model demonstrated that fatigue-related reduced activity and physical fatigue were selected in >95 % of the bootstrap samples with median odds ratio 0.89 (2.5-97.5 % quantiles: 0.78-1.00) and 0.91 (2.5-97.5 % quantiles: 0.81-0.97), respectively, while disease activity was selected in 82 % of the bootstrap samples with median odds ratio 0.90. Moderate to vigorous physical activity in patients with rheumatoid arthritis is associated with the absence of several RA-related factors with the most important correlates being reduced activity due to fatigue, physical fatigue and disease activity.

Sleep quality and correlates of poor sleep in patients with rheumatoid arthritis.

The objective of this study is to examine sleep quality and correlates of poor sleep in patients with rheumatoid arthritis (RA). Five hundred patients with RA were recruited from a rheumatology outpatient clinic and included in this cross-sectional study. Sleep quality and disturbances were assessed using the Pittsburgh Sleep Quality Index (PSQI). Other instruments included the Multidimensional Fatigue Inventory, the Epworth Sleepiness Scale, and the Health Assessment Questionnaire. Disease activity was assessed according to disease activity score DAS28-CRP-based. Complete scores on PSQI were obtained from 384 patients (77 %). In those, the prevalence of poor sleep (PSQI >5) was 61 %, and the mean global PSQI score was 7.54 (SD 4.17). A linear association was found between poor sleep and mental fatigue, reduced activity related to fatigue, physical fatigue, and general fatigue. Mental fatigue and general fatigue were independently associated with sleep quality, sleep latency, sleep duration, sleep efficiency, and daytime dysfunction. However, in the linear multivariate analysis, only general fatigue 1.06 (95 % CI 1.03-1.09) and mental fatigue 1.03 (95 % CI 1.01-1.05) were found to be significant correlates for reporting poor sleep. This study shows that a majority of patients with RA experience poor sleep and that general fatigue and mental fatigue are associated with poor sleep.

Safety and efficacy of resistance training in germ cell cancer patients undergoing chemotherapy: a randomized controlled trial.

BACKGROUND: Bleomycin-etoposid-cisplatin (BEP) chemotherapy is curative in most patients with disseminated germ cell cancer (GCC) but also associated with toxic actions and dysfunction in non-targeted tissues. We investigated changes in muscle function during BEP and the safety and efficacy of resistance training to modulate these changes. METHODS: Thirty GCC patients were randomly assigned to resistance training (resistance training group (INT), n=15) or usual care (CON, n=15) during 9 weeks of BEP therapy. Resistance training consisted of thrice weekly sessions of four exercises, 3-4 sets/exercise of 10-15 repetitions at 12-15 repetition maximum load. The primary endpoint was muscle fibre size, assessed in muscle biopsies from musculus vastus lateralis. Secondary endpoints were fibre phenotype composition, body composition, strength, blood biochemistry and patient-reported endpoints. Healthy age-matched subjects (REF, n=19) performed the same RT-programme for comparison purposes. RESULTS: Muscle fibre size decreased by -322 µm(2) (95% confidence interval (CI): -899 to 255; P=0.473) in the CON-group and increased by +206 µm(2) (95% CI: -384 to 796; P=0.257) in the INT-group (adjusted mean difference (AMD), +625 µm(2), 95% CI: -253 to 1503, P=0.149). Mean differences in type II fibre size (AMD, +823 µm(2), P=0.09) and lean mass (AMD, +1.49 kg, P=0.07) in favour of the INT-group approached significance. The REF-group improved all muscular endpoints and had significantly superior changes compared with the INT-group (P<0.05). CONCLUSIONS: BEP was associated with significant reduction in lean mass and strength and trends toward unfavourable changes in muscle fibre size and phenotype composition. Resistance training was safe and attenuated dysfunction in selected endpoints, but BEP blunted several positive adaptations observed in healthy controls. Thus, our study does not support the general application of resistance training in this setting but larger-scaled trials are required to confirm this finding.

Programming of glucose-insulin homoeostasis: long-term consequences of pre-natal versus early post-natal nutrition insults. Evidence from a sheep model.

AIM: Exposure to adverse intra-uterine conditions can predispose for metabolic disorders later in life. By using a sheep model, we studied (i) how programming of glucose-insulin homoeostasis during late gestation is manifested later in life depending on the early post-natal dietary exposure and (ii) whether dietary alteration in obese individuals can prevent adverse outcomes of early life programming. METHODS: During late gestation, twin-pregnant sheep were fed 100% (NORM) or 50% (LOW) of energy and protein requirements. After birth, offspring were exposed to a moderate (CONV) or high-carbohydrate-high-fat (HCHF) diet until around puberty. Offspring remaining thereafter (exclusively females) were fed a moderate diet until young adulthood. RESULTS: LOW lambs had increased insulin secretory responses during intravenous glucose tolerance tests indicative of reduced insulin sensitivity. HCHF lambs were hypertriglyceridaemic, 75% had mild pancreatic collagen infiltration, and their acute insulin secretory response and insulin clearance during intravenous glucose and insulin tolerance tests, respectively, were reduced. However, NORM-HCHF in contrast to LOW-HCHF lambs had normal glucose tolerance, indicating that later health outcomes are highly influenced by pre-natal nutrition. Dietary alteration normalized glucose-insulin homoeostasis in adult HCHF females, whereas late-gestation undernutrition (LOW) permanently depressed insulin sensitivity. CONCLUSION: Maintenance of glucose tolerance in sheep exposed to pre-natal undernutrition relied on pancreatic hypersecretion of insulin to compensate for reduced insulin sensitivity. A mismatching high-fat diet in early post-natal life interfered with this pancreatic hypersecretion resulting in reduced glucose tolerance. Early post-natal, but not late pre-natal, impacts on glucose-insulin homoeostasis could be reversed by dietary correction later in life.

Left atrial volume and phasic function in clinically healthy dogs of 12 different breeds.

The left atrium (LA) of the heart is a validated marker of clinical and subclinical cardiovascular disease. Since the LA is a three-dimensional structure, volume-based methods of chamber quantification might be more accurate than linear methods. The aims of this study were to establish the feasibility and reproducibility of biplane two-dimensional echocardiographic LA volume measurements and to provide reference ranges for LA volume and phasic function in adult dogs (n=237) without cardiovascular disease. The study also assessed the effects of bodyweight (BW), breed, sex, age and heart rate (HR) on LA volume and function. The biplane area-length method was used to calculate LA volumes from the left apical four- and two-chamber views. LA volume and function were correlated with body size and there were significant breed differences. For dogs of all sizes and breeds, LA maximal volume had a 95th percentile of 0.92 mL/kg. There was no correlation between age or sex and LA volume or LA reservoir function, but conduit function decreased and booster pump function increased with age. LA volume and function varied with HR. LA size was calculated using the biplane area-length method, with good reproducibility and little inter-observer variability. The reference ranges presented for LA volume and function in healthy dogs could be used to refine the diagnostic criteria for the assessment of LA enlargement and altered function by conventional echocardiography.

Efficacy of multimodal exercise-based rehabilitation on physical activity, cardiorespiratory fitness, and patient-reported outcomes in cancer survivors: a randomized, controlled trial.

BACKGROUND: Sedentary behavior and impaired cardiovascular reserve capacity are common late effects of cancer therapy emphasizing the need for effective strategies to increase physical activity (PA) in cancer survivors. We examined the efficacy of a 12-month exercise-based rehabilitation program on self-reported PA, cardiorespiratory fitness (VO2peak), strength, and patient-reported outcomes. PATIENTS AND METHODS: Two hundred fourteen post-treatment cancer survivors were randomly assigned to a 12-month rehabilitation program consisting of individual (x3) and group-based (x6) counseling in combination with once weekly high-intensity group-based exercise training (the Copenhagen Physical Activity after Cancer Treatment, PACT; n = 108) or to a health evaluation program (HE, n = 106). Study outcomes were assessed at baseline, 6 months, and 12 months. RESULTS: After 12 months, the percentage of patients reporting meeting PA goal behavior (≥3 h/week) was significantly increased in the PACT group versus the HE group (70.4% versus 43.4%, P = 0.001). Repeated measures analyses indicated a statistically significant improvement in VO2peak (l min(-1)) in favour of PACT (treatment effect ratio = 1.04; 95% confidence interval 1.00-1.07; P = 0.032). Significant between group differences were also observed for strength (P < 0.001), depression (P = 0.020) and mental health (P = 0.040). CONCLUSION: A 12-month exercise-based rehabilitation program is an effective strategy to promote PA and improve VO2peak in cancer survivors.