Change in left atrial and ventricular dimensions during and immediately after exercise

Purpose: The aim of this study was to evaluate differences in the left atri al (LAD), total ventricular end-diastolic (TEDD), end-systolic diameters (T ESD), and left Ventricular shortening fraction (SF) compared with heart rat e (HR) and systolic blood pressure (SBP) during exercise and recovery. Meth ods: Healthy young male (N = 15) and female (N = 16) subjects performed an incremental cycle ergometer test in upright position, and three phases of e nergy supply were defined by means of blood lactate concentration (LA) and respiratory gas exchange variables (I: aerobic; II: aerobic-anaerobic trans ition. III: anaerobic). Subjects were required to rest their arms on a stee ring bar and to lean their upper body forward; two dimensional (2-D) echoca rdiograms were obtained over the left parasternal area at rest (R), at the end of each phase, immediately within 15 s post, and 6 min after exercise ( 6 min). By using VINGMED's "Anatomical M-Mode," it was possible to extract M-Mode Sweeps from stored 2-D-Loops and perform the M-Made measurement. Res ults: In contrast to the significant decrease in TEDD and TESD from III to 15 a up to resting values and the significant increase in SF from III to 15 s, the moderate decrease in HR immediately post exercise (15 s) was not sig nificant. The SEP showed a significantly decrease from III to 15s: in contr ast to TEDD, TESD, and SF. the Values at 15 s were comparable with the valu es at II. For LAD, significant increase during exercise and a decrease duri ng recovery were observed. Sex-specific differences of changes in measured variables could not be found. Conclusion: We concluded that post exercise m easurement of left Ventricular and atrial dimensions or SF were not valid t o describe heart function at maximal exercise although immediately post exe rcise HR was near maximal level.