The use of TDI to quantify LV systolic and diastolic function is becoming more popular in clinical care as well as in physiological experiments. Our data indicate that Sm and Em are reduced in healthy older adults during IFHG and CPT. Furthermore, greater pressor responses to these laboratory stressors were associated with larger decrements in myocardial systolic and diastolic function in the older adults. Taken together, suboptimal LV adaptations to SNS stress may partly explain why acute heavy exertion (i.e., acute increases in afterload and myocardial O2 demand in the face of a sympathetic "brake" on the coronary vasculature) can trigger myocardial ischemia in certain individuals (44). Future studies evaluating the effects of healthy aging and aerobic exercise training on LV function during sympathetic stress are much needed.
All Science Journal Classification (ASJC) codes
- Physiology (medical)