Frequency of second-degree atrioventricular heart blocks in dogs.
Clinically normal adult dogs and pups 8 to 24 weeks of age were monitored for 2nd-degree atrioventricular (AV) heart block. Radiotelemetry was used to obtain the electrocardiogram (ECG) of resting, unanesthetized, unrestrained dogs. Second-degree AV heart block was detected in 64% of 11 adult dogs and 100% of 12 pups between 8 and 11 weeks of age. The dropped beats, prolonged P-R intervals, and prolonged P-P intervals appeared to be associated with the respiratory cycle. Atropine quickly reduced the frequence of dropped beats. It was concluded that occasional dropped ventricular beats due to 2nd-degree AV heart block may be normal in dogs, especially young dogs.
D000818:Animals; D001285:Atropine / Q000494:pharmacology; D004283:Dog Diseases / Q000503:physiopathology*; D004285:Dogs / Q000502:physiology*; D004562:Electrocardiography; D004567:Electrodes, Implanted; D005260:Female; D006327:Heart Block / Q000503:physiopathology / Q000662:veterinary*; D006339:Heart Rate / Q000187:drug effects; D006352:Heart Ventricles / Q000503:physiopathology; D008297:Male; D012119:Respiration; D013686:Telemetry; D016276:Ventricular Function
D001285:Atropine