CASE REPORT CASE REPORT Longstanding Blood Pressure Control in a Cat with Essential Hypertension

. A case of a nine-year-old spayed Himalayan female, weighing 3.2 kg, on the basis of endocardial hyperechogenicity and accumulation of pleural e # usion, the home doctor gave a diagnosis of restrictive cardiomyopathy (RCM) to start a therapy, but without any improvement in clinical conditions, the cat was introduced to Veterinary Medical Teaching Hospital, Nippon Veterinary and Life Science University. The chief complaints at first medical were hypodynamia, anorexia, polyposia and polyuria, rapid breathing and change in eye color. Systolic blood pressure, mean blood pressure, and diastolic blood pressure by noninvasive blood pressure measurement were 223 mmHg, 189 mmHg, and 158 mmHg respectively. From the results of ultrasound diagnosis, blood hormone concentration measurement, and serum chemistry, we gave this case a tentative diagnosis of essential hypertension. However, the existence of mild endocardial hyperechogenicity and irregularity did not allow us to exclude RCM through diagnosis by exclusion at this moment. Treatment was started with diltiazem hydrochloride, angiotensin converting enzyme inhibitor, and dipyridamole. With decreased systolic blood pressure from 210 (cid:1) 230 mmHg before treatment to 180 (cid:1) 190 mmHg and improved general condition, the same treatment was continued. Endocardial hyperechogenicity at the first medical examination disappeared in the later echocardiography. Therefore, RCM was excluded through diagnosis by exclusion, and consequently, the cat was diagnosed with essential hypertension. The general condition was stable for a while, but systolic blood pressure went over 200 mmHg again, and clinical conditions such as hypodynamia and anorexia appeared. By changing medication from diltiazem hydrochloride to amlodipine besilate, blood pressure immediately decreased and clinical conditions improved. After more than 5 years from the first administration of amlodipine besilate, the cat is maintaining good blood pressure control and clinical status with systolic blood pressure of 130 (cid:1) 160 mmHg.