F. KRAFT-HUNTER AND E. W. HAWTHORNE 
641 
STROKE WORK / END-DIASTOLIC VOL. 
- DOG * 132 
VENTRICULAR PACING + CONTROL ( 11 P O DAY) 
Y= - 9.65 + 1. 128 X(l) 
Y= - 31.5 + 1.548 X (2) 
25 
50 
M L 
75 
100 
Figure 8. — A comparison between the regression lines for atrial (1) and ventricular (2) pacing. The individual 
points were obtained from the individual cardiac cycles analyzed at different ventricular pacing rates and 
during a control period. The data upon which this plot is based is shown in Tables I and II. 
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