Intermittent Sinus Arrest in a Brachycephalic Breed With an Upper Respiratory Disorder . The Pauses (1 and 1.44 Seconds) are Greater Than Twice the Normal P-P Interval (0.46). (From: Tilley LP. Essentials of Canine and Feline Electrocardiography, 3rd Ed. Baltimore: Williams & Wilkins, 1992, With Permission.)