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.

Patent ductus arteriosus occlusion in small dogs utilizing a low profile Amplatz® canine duct occluder prototype.

OBJECTIVES: To develop procedural methodology and assess the safety, utility and effectiveness of a low profile Amplatz(®) canine duct occluder (ACDO) prototype in dogs deemed too small to undergo ductal occlusion with the commercially-available ACDO device. ANIMALS: Twenty-one dogs with left-to-right shunting patent ductus arteriosus (PDA). Dogs were ≥1.5 kg but considered too small to accommodate a 6 Fr catheter or 4 Fr sheath within the femoral artery. METHODS: Prospective canine study using a low profile ACDO prototype delivered through a 4 Fr catheter via a femoral arterial approach. Procedural methods, fluoroscopy time, perioperative complications, and residual ductal flow were evaluated, and angiographic ductal morphology and dimensions were tabulated. RESULTS: All 21 dogs underwent successful ductal occlusion using the prototype device, 4 Fr catheter, and right femoral artery approach. No perioperative complications or device embolization occurred. The median minimal ductal diameter was 1.9 mm (range, 0.4-3.4), and the median device size deployed was 4 mm (range, 3-6). Complete ductal occlusion was noted in 17 dogs (81%) on post-deployment angiography. Twenty dogs (95%) had no residual flow on echocardiography performed the following day. In the 17 dogs (81%) that returned for a long-term (≥3months) follow-up evaluation, all had complete ductal occlusion based on echocardiography. CONCLUSIONS: The low profile ACDO prototype is a safe and effective method of PDA occlusion in the small dog. The deployment procedure appears of similar technical difficulty to the commercially available ACDO.

Structural and functional cardiovascular changes and their consequences following interventional patent ductus arteriosus occlusion in dogs: 24 cases (2000-2006).

OBJECTIVE: To investigate cardiovascular changes and survival times following complete interventional device occlusion of uncomplicated left-to-right shunting patent ductus arteriosus in dogs. DESIGN: Retrospective cohort study. ANIMALS: 24 dogs with uncomplicated patent ductus arteriosus that was fully occluded and reevaluated within 24 hours, approximately 3 months, and 1 year after the procedure. PROCEDURES: Information on medical history, diagnostic imaging findings, treatment received, and survival times were obtained from medical records. Patients were allocated into 2 groups on the basis of age (< 1 year [n = 14] and ≥ 1 year [10]) at the time of the procedure. Additional follow-up information was obtained through interviews of owners and referral veterinarians. RESULTS: Following ductal occlusion, decreases were detected in vertebral heart scale size, left ventricular chamber diameter in diastole and in systole, left atrial dimension, fractional shortening, aortic velocity, and ventricular wall thickness. There were no differences between age groups for postocclusion changes except vertebral heart scale size. Systolic dysfunction was detected in 14 (58%) patients on the final visit. Median survival time for all dogs after ductal occlusion was > 11.5 years. CONCLUSIONS AND CLINICAL RELEVANCE: Complete ductal occlusion resulted in immediate removal of the volume overload state and eventual return of cardiac chamber dimensions to reference range, suggesting regression of eccentric hypertrophy. Systolic dysfunction persisted in some dogs but appeared to be clinically unimportant. Most cardiovascular changes were independent of patient age at the time of the procedure.

Minimally invasive per-catheter occlusion and dilation procedures for congenital cardiovascular abnormalities in dogs.

With ever-increasing sophistication of veterinary cardiology, minimally invasive per-catheter occlusion and dilation procedures for the treatment of various congenital cardiovascular abnormalities in dogs have become not only available, but mainstream. Much new information about minimally invasive per-catheter patent ductus arteriosus occlusion has been published and presented during the past few years. Consequently, patent ductus arteriosus occlusion is the primary focus of this article. Occlusion of other less common congenital cardiac defects is also briefly reviewed. Balloon dilation of pulmonic stenosis, as well as other congenital obstructive cardiovascular abnormalities is discussed in the latter part of the article.