Retrospective evaluation of the incidence and prognostic significance of spontaneous echocardiographic contrast in relation to cardiac disease and congestive heart failure in cats: 725 cases (2006-2011).

OBJECTIVE: To determine whether the presence of spontaneous echocardiographic contrast (SEC) in cats with cardiomyopathy is associated with increased mortality. To establish whether specific types of cardiomyopathy are more often associated with SEC in an attempt to provide a risk-stratification scheme for cats with increased risk of thromboembolic events. DESIGN: Retrospective study 2006-2011. SETTING: Tertiary referral and teaching hospital. ANIMALS: Seven hundred twenty-five client-owned cats undergoing echocardiographic evaluation. MEASUREMENTS AND MAIN RESULTS: Patient characteristics, including age, breed, clinical signs, type of cardiovascular disease, presence of SEC, and survival time were recorded. Thyroxine, HCT, and blood pressure were recorded when available. Among cats diagnosed with cardiac abnormalities based on echocardiographic findings, those with SEC were at significantly increased risk of death as compared to those without SEC. Cats with dilated cardiomyopathy, unclassified cardiomyopathy, and hypertrophic cardiomyopathy were significantly more likely to have SEC compared to cats with other types of cardiac disease. CONCLUSIONS: Cats with cardiomyopathy and SEC have an increased risk of death compared to cats without SEC, although other previously identified factors such as the presence of congestive heart failure and increased left atrium to aorta ratio remain important determinants of mortality. Cats with hypertrophic cardiomyopathy, unclassified cardiomyopathy, and dilated cardiomyopathy may benefit from anticoagulant therapy due to the increased risk of SEC in these subpopulations.

Secondary prevention of cardiogenic arterial thromboembolism in the cat: The double-blind, randomized, positive-controlled feline arterial thromboembolism; clopidogrel vs. aspirin trial (FAT CAT).

OBJECTIVES: To determine if clopidogrel administration is associated with a reduced likelihood of recurrent cardiogenic arterial thromboembolism (CATE) in cats compared to aspirin administration. Secondary aims were to determine if clopidogrel administration had an effect on the composite endpoint of recurrent CATE and cardiac death and to identify adverse effects of chronic clopidogrel or aspirin therapy. ANIMALS: Seventy-five cats that survived a CATE event. METHODS: Multicenter, double-blind, randomized, positive-controlled study. Cats were assigned to clopidogrel (18.75 mg/cat PO q 24 h) or aspirin (81 mg/cat PO q 72 h). Kaplan-Meier survival curves were created for each endpoint and the log rank test performed to compare treatment groups with respect to time to event and the likelihood of the event occurring. RESULTS: The mean age of all cats was 8.0 ± 3.5 yr and 57/75 (76%) were male (p < 0.001); 62/75 (83%) were mixed breed with the remainder including Persian, Abyssinian, American Shorthair, Bengal, Birman, Himalayan, Maine Coon, Ragdoll, Snowshoe, and Sphynx breeds. Only 15% (11/75) of cats had a history of heart disease recorded prior to the CATE event. Clopidogrel administration was associated with significantly reduced likelihood of recurrent CATE compared to aspirin (p = 0.024) and had a longer median time to recurrence [443 (95% CI 185-990) days vs. 192 (95% CI 62-364) days, respectively]. Clopidogrel was also associated with a significantly reduced likelihood of the composite endpoint of recurrent CATE or cardiac death (p = 0.033) with a longer median time to event [346 (95% CI 146-495) days vs. 128 (95% CI 58-243) days]. CONCLUSIONS: Clopidogrel administration significantly reduces the likelihood of recurrent CATE compared with aspirin in cats; both drugs were well tolerated.

Echocardiographic and electrocardiographic findings in client-owned ferrets: 95 cases (1994-2009).

OBJECTIVE: To characterize echocardiographic and ECG findings in ferrets (Mustela putorius furo) evaluated at a clinical practice. DESIGN: Retrospective case series. ANIMALS: 95 client-owned ferrets. PROCEDURES: Medical records of all ferrets that had a cardiac evaluation (echocardiogram with or without ECG) performed between January 1994 and November 2009 were reviewed. Data analyzed included signalment; primary clinical sign or physical examination finding that prompted cardiac evaluation; echocardiographic diagnosis; ECG diagnosis; radiographic diagnosis (if radiographs were obtained within 1 month before or after the echocardiogram); presence of congestive heart failure (CHF) defined as pulmonary edema, pleural effusion, or ascites determined to be of cardiac origin; and any available follow-up echocardiographic or ECG diagnoses. RESULTS: Valvular regurgitation (VR) was the most common abnormal echocardiographic finding and was diagnosed in 49 of 95 ferrets, of which 44 had aortic VR, 24 had mitral VR, and 23 had > 1 valve affected. Congestive heart failure was diagnosed in 17 of 95 ferrets, which included all 4 ferrets that had dilated cardiomyopathy. Of the 65 ferrets with ECG results, 26 had atrioventricular block, of which 7 had third-degree atrioventricular block and 6 had CHF, syncope, or weakness. CONCLUSIONS AND CLINICAL RELEVANCE: The most frequent echocardiographic abnormality found in ferrets was VR, most commonly affecting the aortic and mitral valves. Dilated cardiomyopathy was infrequently diagnosed but was generally associated with CHF. The most frequent ECG abnormality was atrioventricular block, and third-degree atrioventricular block was often associated with CHF, weakness, or syncope.

Development and evaluation of a questionnaire for assessment of health-related quality of life in cats with cardiac disease.

OBJECTIVE: To develop, validate, and evaluate a questionnaire (Cats' Assessment Tool for Cardiac Health [CATCH] questionnaire) for assessing health-related quality of life in cats with cardiac disease. DESIGN: Prospective study. ANIMALS: 275 cats with cardiac disease. PROCEDURES: The questionnaire was developed on the basis of clinical signs of cardiac disease in cats. A CATCH score was calculated by summing responses to questionnaire items; possible scores ranged from 0 to 80. For questionnaire validation, owners of 75 cats were asked to complete the questionnaire (10 owners completed the questionnaire twice). Disease severity was assessed with the International Small Animal Cardiac Health Council (ISACHC) classification for cardiac disease. Following validation, the final questionnaire was administered to owners of the remaining 200 cats. RESULTS: Internal consistency of the questionnaire was good, and the CATCH score was significantly correlated with ISACHC classification. For owners that completed the questionnaire twice, scores were significantly correlated. During the second phase of the study, the CATCH score ranged from 0 to 74 (median, 7) and was significantly correlated with ISACHC classification. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that the CATCH questionnaire is a valid and reliable method for assessing health-related quality of life in cats with cardiac disease. Further research is warranted to test the tool's sensitivity to changes in medical treatment and its potential role as a clinical and research tool.

Use of pimobendan in 170 cats (2006-2010).

HYPOTHESIS/OBJECTIVES: To describe the therapeutic use of pimobendan in cats, describe the patient population to which it was administered, document potential side effects and report the clinical course following administration of pimobendan in conjunction with standard heart failure therapy. It is hypothesized that cats with advanced heart disease including congestive heart failure from a variety of causes will tolerate pimobendan with a minimum of side effects when used in treatment in conjunction with a variety of other medications. ANIMALS, MATERIALS AND METHODS: One hundred and seventy client owned cats with naturally occurring heart disease, one hundred and sixty four of which had congestive heart failure. Medical records were reviewed and owners and referring veterinarians were contacted for follow-up data. Data collected included pimobendan dose, other medications administered concurrently, data collected at physical examination, presence or absence of heart failure, adverse effects, classification of heart disease, echocardiographic data and survival time. The data were analyzed for significance between the initial visit and any follow-up visits. RESULTS: All cats were treated with pimobendan. The median pimobendan dose was 0.24 mg/kg q 12 h. Pimobendan was used in combination with multiple concurrent medications including angiotensin converting enzyme inhibitors, diuretics and anti-thrombotics. Five cats (3.0%) had potential side effects associated with pimobendan. One cat (0.6%) had presumed side effects severe enough to discontinue pimobendan use. Median survival time for 164 cats with congestive heart failure after initiation of pimobendan was 151 days (range 1-870). CONCLUSION: Pimobendan appears to be well tolerated in cats with advanced heart disease when used with a variety of concurrent medications. Randomized controlled studies need to be performed to accurately assess whether it is efficacious for treatment of congestive heart failure in cats.

Atrial fibrillation in cats: 50 cases (1979-2002).

OBJECTIVE: To determine signalment, clinical signs, diagnostic findings, treatment, and outcome for cats with atrial fibrillation (AF). DESIGN: Retrospective study. ANIMALS: 50 cats. PROCEDURE: Medical records of cats that met criteria for a diagnosis of AF (ECG consisting of at least 2 leads, clear absence of P waves, supraventricular rhythm, and convincingly irregularly irregular rhythm) and had undergone echocardiography were reviewed. RESULTS: There were 41 males (37 castrated) and 9 females (7 spayed). Forty-one were of mixed breeding; 9 were purebred. Mean +/- SD age was 10.2 +/- 3.7 years. The most common chief complaints were dyspnea, aortic thromboembolism, and lethargy. In 11 cats, AF was an incidental finding. Mean +/- SD ventricular rate was 223 +/- 36 beats/min. The most common echocardiographic abnormalities were restrictive or unclassified cardiomyopathy (n = 19), concentric left ventricular hypertrophy (18), and dilated cardiomyopathy (6). Mean +/- SD left atrial-to-aortic diameter ratio (n = 39) was 2.55 +/- 0.80. The most common thoracic radiographic findings were cardiomegaly, pleural effusion, and pulmonary edema. Median survival time (n = 24) was 165 days (range, 0 to 1,095 days). Eight of 24 cats lived for > or = 1 year after a diagnosis of AF was made. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that AF occurs primarily in older adult male cats with structural heart disease severe enough to lead to atrial enlargement. Atrial fibrillation in these cats was most commonly first detected when signs of decompensated cardiac disease were evident, but also was commonly identified as an incidental finding.

Assessment of the prevalence of heart murmurs in overtly healthy cats.

OBJECTIVE: To assess the frequency of heart murmurs in overtly healthy cats. DESIGN: Prospective study. SAMPLE POPULATION: 103 healthy domestic cats. PROCEDURE: Background information and physical characteristics were assessed in cats that were candidates for blood donation during an 8-month period. For cats with heart murmurs, additional information collected included murmur timing, grade, point of maximal intensity, and presence of additional heart sounds. RESULTS: Heart murmurs were detected in 22 of the 103 (21%) cats. Echocardiography was performed in 7 of those 22 cats. The echocardiogram was considered normal in 1 cat; in the other 6 cats, diagnoses included hypertrophic cardiomyopathy (interventricular septal hypertrophic form [IVSH]; n = 4), left ventricular concentric hypertrophy with valvular disease (1), and equivocal IVSH (1). Thirteen cats had more than 1 examination during the study; 3 of them developed heart murmurs. There were no significant differences in age, sex, breed, coat color, eye color, or heart rate between cats with and without murmurs. Among the 103 cats, there were 6 pairs of siblings from 6 multiple-cat households and 16 cats from 7 multiple-cat households in which the cats were not related; the proportion of cats with murmurs was higher in the related cats (5/12) than in the unrelated cats (3/16), but the difference was not significant. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that heart murmurs are detectable in a large proportion of overtly healthy cats and that many murmurs appear to be caused by structural heart disease that is in a clinically latent state.