Abstract 13890: Exercise Capacity is Associated with Endothelin-1 Release During Emotional Excitement

Abstract

Background: The circulating endothelin-1 and catecholamines are increased and heart rate variability decreased during emotional excitement but the individual responses are variable. We tested the hypothesis that cardiorespiratory fitness expressed as maximal exercise capacity is associated with the magnitude of physiological responses caused by real-life emotional excitement.

Methods: We measured the plasma levels of endothelin-1, catecholamines and global R-R interval variability (SDNN) in 67 enthusiastic male ice hockey spectators (age; 57 ± 10 years) with stable coronary artery disease (CAD, n=51) and healthy subjects (n=16) at baseline and during the Finnish national league ice hockey play-off final matches. Maximal exercise capacity (METs) was measured by bicycle exercise test on a separate day.

Results: Maximal METs correlated with the circulating endothelin-1 at rest in CAD patients (r=-0.43, p=0.004) but not in healthy subjects (r=-0.26, p=0.35). Maximal METs correlated even more strongly with the circulating endothelin-1 measured during the emotional stress in CAD patients (r=-0.52, p<0.001) and healthy subjects (r=-0.51, p=0.054). The change of endothelin-1 between baseline and emotional stress also correlated with maximal METs in both groups, r=-0.30 and r=-0.55 for CAD and healthy subjects, respectively (p<0.05 for both). Maximal METs did not correlate with the catecholamines or SDNN at any condition.

Conclusion: Physical fitness is associated with endothelin-1 release during emotional excitement in CAD patients and healthy subjects, perhaps partly explaining its protective effects for cardiovascular events.