Small Talk - Autumn 2017

by Malcolm Cobb MA VetMB DVC PhD MBA FHEA MRCVS Pride Veterinary Centre I n the early stages of heart failure, the output of the heart is maintained by a number of compensatory mechanisms, in other words, the heart manages to maintain function even though the disease itself deteriorates. In time however, a rise in blood pressure and fluid retention leads to notable signs of breathing difficulty. Treatment for heart failure is not curative, but it is generally aimed at reducing the congestion and fluid retention which develops. A variety of drugs are used, the effects of which aim to remove excess fluid and help prevent it developing, and improve heart function. Such drugs include furosemide, angiotensin converting enzyme inhibitors (such as benazepril), Pimobendan and spironolactone. In veterinary medicine, the common causes of heart disease (valve disease and cardiomyopathies), are not curable. In time, in a large proportion of patients with heart disease the disease itself will ultimately lead to heart failure, a clinical syndrome best described as a heart which cannot pump adequate volumes of blood to the tissues. Cardiology medication - the importance of compliance Cardiology Treatment 04 small talk Cardiac output Compensatory mechanisms sympathetic activity renin-angiotensin-aldosterone system antidiuretic hormone Excessive vasoconstriction sodium and water retention Preload and afterload Heart failure The vicious cycle involved in heart failure Figure 1