tailieunhanh - Báo cáo khoa học: "A Combination of Atrioventricular Block and Sinoatrial Block in a Horse"

Tuyển tập các báo cáo nghiên cứu về bệnh thú y được đăng trên tạp chí y học General Psychiatry cung cấp cho các bạn kiến thức về ngành y đề tài: A Combination of Atrioventricular Block and Sinoatrial Block in a Horse. | Acta vet. scand. 2005 46 173-175. Brief Communication A Combination of Atrioventricular Block and Sinoatrial Block in a Horse By A. Rezakhani M. Godarzi Naeini Department of Clinical Studies School of Veterinary Medicine Shiraz University . Box 1731 Shiraz 71345 Iran. In the process of carrying out a routine check up examination on a group of horses of a riding school in Shiraz a horse demonstrated frequent long pauses in heart rate of 33beats per minute on auscultation. A base apex electrocardiogram ECG was recorded to determine the type of conduction disturbance. At the time of ECG recording the animal was normal with no apparent sign of any body disorders and respiratory movement and temperature were within normal range. CBC and serum biochemical analysis carried out were within normal limits of our school reference values. The horse was given a light exercise and was examined immediately after exercise and 15 minutes thereafter. The heart rate immediately after the end of exercise was 65 bpm and slowed down to 35 bpm 15 minutes after exercise with no sign of heart block. ECG interpretation The first two complexes of the ECG appeared to be conducted normally through the heart following initiation of the sinoatrial node however the P-R interval was variable and the third P wave was blocked at the A-V node. The mean P-P interval was about second indicating a sinus rate of 33 beats per minute. Following the first blocked P-wave there was a long pause which was slightly more than twice the previous P-P interval. There was no electrical activity during this pause indicating a concomitant sinoatrial block SAB . The underlying rhythm was sinus arrhythmia as the P-P or R-R intervals were variable. There was also a single atrioventricular block AVB in the second trace. No single SAB without accompanying AVB was observed on the ECG. Discussion The prevalence of cardiac arrhythmias among domestic animals is more common in the horse McGuirk Muir .