Comparative echocardiographic and clinical features of hypertrophic cardiomyopathy in 5 breeds of cats: a retrospective analysis of 344 cases (2001-2011).

BACKGROUND: Primary hypertrophic cardiomyopathy (HCM) is the most common feline heart disease and has been demonstrated to be inherited in some breeds. However, few studies have compared HCM phenotypes and survival according to breed. OBJECTIVES: To compare epidemiological characteristics, clinical findings, left ventricular (LV) geometric patterns, and survival in several breeds of cats with HCM. ANIMALS: Three hundred and forty-four cats from 5 different breeds (Persian, Domestic Shorthair [DS], Sphynx, Maine coon [MC], and Chartreux) with primary HCM diagnosed by conventional echocardiography. METHODS: Retrospective study. Cats were classified according to breed and clinical status. RESULTS: Age at the time of diagnosis was lower (P < .001) in MC (median age, 2.5 years) and Sphynx (3.5 years) than in other breeds (OB), ie, 8.0, 8.0, and 11.0 years for DS, Chartreux, and Persians, respectively. The prevalence of LV outflow tract obstruction was higher (P < .001) in Persians (23/41; 56%) than in OB (115/303; 38%). Age at the first cardiac event was lower (P < .01) in MC (median age, 2.5 years) than in OB (7.0 years). All cats surviving > 15 years of age were DS, Persians, or Chartreux. Sudden death (representing 24% of all cardiac deaths) was observed only in 3 breeds (DS, MC, and Sphynx). CONCLUSION AND CLINICAL IMPORTANCE: As in humans, feline HCM is characterized by marked phenotypic variability with several breed-dependent features regarding epidemiology, LV geometric patterns, and clinical course (ie, age at diagnosis, 1st cardiac event, and cause of death).

Association of plasma N-terminal pro-B-type natriuretic peptide concentration with mitral regurgitation severity and outcome in dogs with asymptomatic degenerative mitral valve disease.

BACKGROUND: The clinical outcome of dogs affected by degenerative mitral valve disease (MVD) without overt clinical signs is still poorly defined, and criteria for identification of animals that are at a higher risk of early decompensation have not yet been determined. HYPOTHESIS: N-terminal pro-B-type natriuretic peptide plasma concentration (NT-proBNP) is correlated with mitral regurgitation (MR) severity and can predict disease progression in dogs with asymptomatic MVD. ANIMALS: Seventy-two dogs with asymptomatic MVD, with or without heart enlargement (International Small Animal Cardiac Health Council: ISACHC classes 1a and 1b), and a control group of 22 dogs were prospectively recruited. METHODS: Severity of MR was quantitatively assessed from the regurgitation fraction (RF) by the proximal isovelocity surface area method. Consequences of MR were evaluated from measurements of the left atrium/aorta ratio (LA/Ao), fractional shortening (FS), end-diastolic and end-systolic left ventricular volumes indexed to body surface area (EDVI and ESVI). The relevance of these echo-Doppler indices and NT-proBNP for prediction of outcome at 12 months was studied. RESULTS: A significant correlation was found between NT-proBNP and RF, LA/Ao, FS, and EDVI (P < .05). NT-proBNP was higher in dogs with MVD (ISACHC classes 1a and 1b) compared with the control group (P= .025 and < .001, respectively). The difference was not significant when only dogs from ISACHC class 1a with RF < 30% were considered. Lastly, NT-proBNP was higher in dogs that underwent MVD decompensation at 12 months (P < .05). CONCLUSIONS AND CLINICAL IMPORTANCE: NT-proBNP is correlated with MVD severity and prognosis in dogs with asymptomatic MVD.

Retrospective study of 156 atrial septal defects in dogs and cats (2001-2005).

Atrial septal defect (ASD) is a common congenital heart disease (CHD) in humans, but considered relatively rare in veterinary medicine. However, modern echocardiographic and Doppler techniques currently offer a good view of the morphology of the interatrial septum, thus facilitating earlier detection of ASD in awake animals. In this context, we carried out a retrospective study of cases of recently diagnosed ASD in dogs and cats at the Cardiology Unit of Alfort (2001-2005) using echocardiography combined with colour Doppler mode. ASD was diagnosed in 156 animals and represented 37.7% of all canine and feline CHDs (n = 414). ASD was the most common CHD after mitral dysplasia in both species. Boxer and Domestic shorthair were the most common canine and feline breeds affected. Most defects (98.7%) were secundum-type ASD, without clinical signs in 73.7% of cases. The most common clinical signs included systolic murmur heard over the left heart base (20.2%), exercise intolerance (7.0%), syncope (5.3%), dyspnoea (2.6%) and cough (2.6%). Animals that presented a systolic heart murmur over the left base had a significantly larger ASD than others (P < 0.05). These data suggest that the incidence of ASD is higher than previously assumed. ASD should be suspected, for example, in instances of left basal systolic heart murmur, although its clinical and haemodynamic consequences are usually minor.