Abstract
Treadmill exercise test was performed in patients with complete A-V block having VDD, DDD pacemakers implanted. Maximum exercise tolerance was 7.4±1.6 Mets in VVI mode pacing (rate 70ppm), 9.4±2.1 Mets in VVI mode pacing (rate 120ppm), 11.5±2.4 Mete in VDD mode (rate 123.2±40.6ppm). The increase of maximum exercise tolerance in VDD mode pacing was attributed to physiological increase in heart rate and atrial function.