Later Development, Develop. Physiol., Dr. D. Penney

Table 3.20 - Change in the Heart with Age - as seen at Rest.

• Prolonged systole and isovolumic diastole.

• Increased LV ejection time.

• Increased pre - ejection period (Q-S₁ & Q-S₂).

• Increased isovolumic relaxation time.

• Increase in P -R, QRS, & Q-T intervals.

• Decreased QRS complex amplitude.

• Decrease in cardIAC output from 3rd to 9th decade (1% per yr.).

• Decrease in stroke volume.

• Increase in A-V O₂ difference.

• Hypertrophy (50 g in 30 yrs.).

• Increased workload due to increased arterial stiffness and hypertension.

• Decreased ventricular/pericardial compliance?

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