International collaborative study to assess cardiovascular risk and evaluate long-term health in cats with preclinical hypertrophic cardiomyopathy and apparently healthy cats: The REVEAL Study.

BACKGROUND: Hypertrophic cardiomyopathy is the most prevalent heart disorder in cats and principal cause of cardiovascular morbidity and mortality. Yet, the impact of preclinical disease is unresolved. HYPOTHESIS/OBJECTIVES: Observational study to characterize cardiovascular morbidity and survival in cats with preclinical nonobstructive (HCM) and obstructive (HOCM) hypertrophic cardiomyopathy and in apparently healthy cats (AH). ANIMALS: One thousand seven hundred and thirty client-owned cats (430 preclinical HCM; 578 preclinical HOCM; 722 AH). METHODS: Retrospective multicenter, longitudinal, cohort study. Cats from 21 countries were followed through medical record review and owner or referring veterinarian interviews. Data were analyzed to compare long-term outcomes, incidence, and risk for congestive heart failure (CHF), arterial thromboembolism (ATE), and cardiovascular death. RESULTS: During the study period, CHF, ATE, or both occurred in 30.5% and cardiovascular death in 27.9% of 1008 HCM/HOCM cats. Risk assessed at 1, 5, and 10 years after study entry was 7.0%/3.5%, 19.9%/9.7%, and 23.9%/11.3% for CHF/ATE, and 6.7%, 22.8%, and 28.3% for cardiovascular death, respectively. There were no statistically significant differences between HOCM compared with HCM for cardiovascular morbidity or mortality, time from diagnosis to development of morbidity, or cardiovascular survival. Cats that developed cardiovascular morbidity had short survival (mean ± standard deviation, 1.3 ± 1.7 years). Overall, prolonged longevity was recorded in a minority of preclinical HCM/HOCM cats with 10% reaching 9-15 years. CONCLUSIONS AND CLINICAL IMPORTANCE: Preclinical HCM/HOCM is a global health problem of cats that carries substantial risk for CHF, ATE, and cardiovascular death. This finding underscores the need to identify therapies and monitoring strategies that decrease morbidity and mortality.

Long-term tolerability of benazepril in dogs with congestive heart failure.

OBJECTIVES: To test the tolerability of long-term administration of benazepril in dogs with congestive heart failure (CHF). METHODS: The study was a prospective, randomized, double-blinded, placebo-controlled clinical trial. A total of 162 dogs with New York Heart Association (NYHA) class II-IV heart failure caused by chronic valvular disease (CVD) or dilated cardiomyopathy (DCM) were enrolled. Benazepril (minimum dosage, 0.25 mg/kg) or placebo were administered orally once daily for up to 34 months. In this paper, we report results of plasma alanine aminotransferase (ALT), creatinine, potassium and urea. RESULTS: The two groups were matched at baseline (p>/=0.18). Plasma creatinine concentrations were lower during treatment with benazepril versus placebo for all dogs (p=0.14) and every sub-group tested (NYHA II, III or IV; CVD; DCM; initial creatinine >124 mumol/L), although statistical significance was not reached (p=0.14-0.6). However, significantly (p=0.035) more cases of creatinine >124 mumol/L during treatment occurred with placebo (47%) as compared to benazepril (30%). Plasma ALT and urea values did not differ between groups for all dogs (p>0.5) or any sub-group (p=0.23-1.0). Plasma potassium values did not differ between groups for all dogs (p>0.5). Although differences approached statistical significance for potassium in some sub-groups (p=0.07-0.1), there were no consistent differences between groups. CONCLUSIONS: Benazepril was well tolerated during long-term therapy in dogs with CHF and no specific precautions appear to be necessary regarding plasma ALT, creatinine, potassium or urea. The possible action of benazepril in improving renal function (evidenced via lower plasma creatinine) merits further investigation.