Figure 1
Electrocardiographic findings in CXMD J A: Sequential studies in electrocardiographic parameters with advancing age in normal and CXMDJ dogs. Heart rate (HR) (beats/min), PQ interval (ms), and duration (ms) of QRS complex on ECG in a normal littermate III-301MN (open circle), and CXMDJ dogs III-302MA (closed circle) and III-303MA (closed square) at 2, 3, 4, 6, 9, 12, 15, 18, and 21 months of age. B: Representative ECGs in normal and CXMDJ male dogs. ECGs were recorded from normal dogs, III-301MN and III-1804MN, and CXMDJ dogs, III-302MA and III-1803MA, at 6 months of age. Distinct deep Q waves were present in the CXMDJ dogs. Leads were recorded at 50 mm/s, 1 cm/mV. C: Sequential studies in Q/R ratios with advancing age in limb leads I, II, III, and aVF in normal and CXMDJ dogs. Q/R ratios in limb leads I, II, III, and aVF in a normal littermate III-301MN (open circle), and the CXMDJ dogs III-302MA (closed circle) and III-303MA (closed square) at 2, 3, 4, 6, 9, 12, 15, 18, and 21 months of age.