Hemodynamic during a postexertional asystolia in a healthy athlete: a casestudy

Hemodynamic events leading to spontaneous postexertional vasovagal syncope are not completely understood because of the lack of beat-to-heat data. We report a case study of a young athlete who undergoes a syncopal episode dur ing the recovery period following a maximal cycle-ergometer test. The episo de was monitored by an impedance cardiograph which can gather noninvasively beat-re-beat the flow of heart rate (HR), stroke volume (SV), cardiac outp ut (CO), diastolic filling rate (SV/DT), and myocardial contractility index (PEP/LVET). The most important findings of this report are the dramatic re duction of SV/DT preceding the syncope, the increment of SV together with t he reduction of HR preceding and following the syncope, the prompt recovery of CO values after the syncopal episode despite the bradycardia, and the r eduction of PEP/LVET after the syncope. This report confirms the importance of active recovery immediately after strenuous exercise and supports the h ypothesis that the reduction of SV/DT in the presence of an inotropic stimu lation can trigger the vasovagal reaction.