摘要 |
There is disclosed an atrial and ventricular pacer having independent rate and AV delay controls. Adjustment of one potentiometer changes the basic pacer rate without affecting the AV delay; adjustment of another potentiometer varies the AV delay without affecting the pacer rate. This is achieved by having the rate control determine the atrial escape interval, a variable one-shot multivibrator being provided to delay the ventricular stimulus after it is triggered simultaneously with the generation of an atrial stimulus. The variable one-shot multivibrator is reset when a spontaneous ventricular beat is detected, and the atrial timing period always begins at the end of a fixed time interval following an atrial stimulus, the fixed time interval being longer than the maximum AV delay. |