Prevalence of iatrogenic heart murmurs in apparently healthy cats
Katie Howell and others, Sarah Smith Cardiology, Etwall, Derbyshire
Heart murmurs have an estimated presence of 20 to 40 percent in cats, and it can be difficult for veterinary clinicians to distinguish between pathological and non-pathological signs. The authors examined 106 apparently healthy cats to determine the prevalence of murmurs and identify any predisposing factors. They report that abnormalities were found in 28.2 percent of the sample, with a strong agreement between the two clinicians involved on both the presence and severity of the murmur. There was a significant association between the presence of abnormal sounds and increasing age and decreasing body condition score.
Journal of Small Animal Practice, 63, 597-602
Cardiopulmonary arrest and resuscitation in hospitalised birds
Amanda Crawford and others, Tufts University, New Grafton, Massachusetts
Birds present a particular challenge for emergency service clinicians as the patients are likely to be severely ill on arrival, and their small size and fast metabolic rate mean their condition can deteriorate further rapidly. The authors examined the records from 41 avian cases that experienced cardiopulmonary arrest during hospitalisation and the strategies employed in their treatment. Three cases saw a return of spontaneous circulation (ROSC), but only one of these patients survived. In cases where ROSC did occur, the patients were under general anaesthesia, were ventilated and had direct monitoring by a clinician, so emergency medications were immediately available.
Journal of Veterinary Emergency and Critical Care, 32, 491-499
Significance of changes in vertebral left atrial size in preclinical mitral valve disease
Dohee Lee and others, Chungbuk National University, South Korea
Measurements of vertebral left atrial size (VLAS) on thoracic radiographs can indicate the extent of left atrial enlargement in dogs with myxomatous mitral valve disease (MMVD). However, it is unclear whether such measurements can accurately identify dogs at greater risk of going on to develop congestive heart failure. The authors examined a sequence of radiographs of 41 dogs with MMVD and retrospectively classified them into groups that did or did not develop heart failure. Their findings suggest that changes in VLAS measures show a high level of accuracy in identifying dogs that will develop congestive heart failure in the next 180 days.
Journal of Veterinary Cardiology, 42, 23-33
Effect of obesity and subsequent weight loss on cardiac structure and function in dogs
Catheryn Partington and others, University of Liverpool, Liverpool
In human patients, obesity is linked to systemic hypertension, cardiac remodelling and systolic and diastolic dysfunction. These changes have been shown to be largely reversible with successful weight reduction. The authors investigated whether similar changes could be observed in dogs on weight control programmes. Twenty-four client-owned dogs were recruited for the trial, of which 12 successfully reached the target weight. The findings confirm that canine obesity is associated with diastolic dysfunction and left ventricular hypertrophy. The latter improved substantially with significant weight loss and fat mass reduction.
BMC Veterinary Research, 18, 351
Comparative efficacy of three different antihypertension drugs in dogs
Hyeong-Il Choi and others, Chonnam National University, South Korea
Systemic arterial hypertension is associated with damage to many organ systems, notably the eyes, brain, heart and kidneys. The authors investigated the underlying causes of hypertension in dogs and the short-term efficacy of three antihypertension drugs. They examined the records from 75 dogs treated for hypertension with amlodipine, ramipril and telmisartan either as a monotherapy or in combination. During a four-week treatment period, the combination of telmisartan and amlodipine showed the greatest decrease in systolic blood pressure.
Topics in Companion Animal Medicine, 50, 100674
Cardiac MRI and biomarkers in detecting myocardial ischaemia and fibrosis in dogs
William Clark and others, Ohio State University, Columbus
Disease progression in dogs with MMVD can be highly variable, and the presence of myocardial ischaemia and/or fibrosis is considered a key prognostic factor. The authors used cardiac MRI and various biomarkers to detect pathological changes in dogs with cardiomegaly secondary to MMVD. Compared with healthy dogs, those with MMVD had significantly higher cardiac troponin I concentrations, but galectin-3 values did not differ between groups. Myocardial fibrosis was detected on cardiac MRI in diseased and healthy animals, so this finding may not be clinically relevant.
American Journal of Veterinary Research, 83
Vertebral heart size and cardiac enlargement in Chihuahuas with mitral valve disease
Daisuke Ito, Vets Heart, Saitama, Japan
Vertebral heart size (VHS) is a radiographic measurement of cardiac enlargement that may be useful in identifying individuals with conditions such as MMVD. However, breed-specific differences in VHS reference ranges have been identified in some smaller breeds. The author compares the findings from radiographic and ultrasound investigations in healthy Chihuahuas and those with MMVD. The results confirm that VHS increased according to the degree of cardiac enlargement in this breed. A VHS measurement of 10.5 indicated mild left-sided cardiomegaly. Dogs with a VHS of 11.1 or more had severe disease as assessed by echocardiography.
Canadian Veterinary Journal, 63, 627-632
Limitations of screening for occult hypertrophic cardiomyopathy in cats
Mark Rishniw, Veterinary Information Network, Davis, California
Occult feline hypertrophic cardiomyopathy (HCM) may result in unexpected sudden death or congestive heart failure following routine veterinary procedures. Therefore, there is an urgent need for a reliable test to screen for at-risk cats before attempting any stressful intervention. The author assesses the utility of the only currently available test, the feline N-terminal pro-brain natriuretic peptide assay, and concludes that this method will detect around half the patients with unidentified HCM. A small proportion of cats without HCM will also test positive. The author suggests that until a better test is developed, clinicians must decide whether a test that can only identify 50 percent of the at-risk cats is better than finding none at all.
