Abstract
Hemodynamic changes similar to normal healthy subjects were observed in patients with implanted permanent pacemaker and fixed heart rate during the sustaincd hand-grip and bicycle ergometer exercise.
The sustained hand-grip exercise caused a slight but significant elevation of blood pressure as well as a slight but significant prolongation of left ventricular ejection time (LVET), while the cardiac index remained unchanged.
On the other hand, during ergometer exercise, the blood pressure, cardiac index and LVET were markedly increased, while the pre-ejection period (PEP), PEP/LVET, isovolumetric contraction time and total peripheral resistance were significantly decreased. So far as the pacing rate is concerned, the increment in cardiac index was slightly augumented and the recovery time of the hemodynamic changes following the exercise was shortened when the pacing rate was increased from 70 to 100, although the differences were not very marked.
The present results indicate that the hemodynamic adjustments to the exercise are appropriately maintained even in the patients with artificial pacemaker and fixed heart rate. The results also suggest that a higher pacing rate than in rutine use may be more appropriate for the exercise.
