Hypertension in dogs and cats: Causes and effects

During the nineties of the past century, several authors underscored the necessity of measuring blood pressure during a regular clinical examination of veterinary patients, because hypertension occurs as an accessory symptom in the course of diseased conditions. In addition to blood pressure measurements, most authors believe that it is necessary also to examine intraocular pressure, like in human medicine. Hypertension can be defined as a chronic increase of the systolic and diastolic blood pressure. Systemic blood pressure is proportionate to the heart rate and total peripheral resistance, while physiological control depends on the reninangiotensin system, aldosterone, prostaglandin, adrenergic and neurogenic factors. Some other factors can also have an influence on the measured values of blood pressure (such as age, sex, race, temperament, environment, and, in part, also how and where the pressure measurement was taken). It has been generally accepted in veterinary medicine than an animal can be considered hypertensive if the measured systolic/diastolic pressures are higher than 180/100 mm Hg. Hypertension can be primary (sometimes also defined as essential or idiopathic) when it is a consequence of several factors which include heart, neurological, kidney, endocrine, and metabolic aspects. Hypertension is defined as secondary when it occurs as a consequence of certain chronic disorders (such as hyperthyroidism, hypothyroidism, hyperadrenocorticism, pheochromocytoma, and diabetes mellitus). Blood pressure can be measured in animals using direct or indirect methods. The oscilometric and the ultrasonographic methods are equally used in the world today. Following detailed studies by large numbers of authors, the physiological frameworks of blood pressure in animals have been precisely determined. Different treatments are applied in the therapy of hypertension in animals, such as: restrictive diets, diuretics, a, and (3 blockers, blockers of calcium channels, vasodilators, ACE inhibitors. Hypertension can also be a state that requires emergency treatment, when it is resolved with aggressive therapy