Sympatho-vagal evaluation during thrombolytic therapy in patients with acute myocardial infarction

The heart rate variability (HRV) signal was studied by means of autoregressive recursive spectral analysis in the first hours after myocardial infarction and during thrombolytic therapy. The HRV signal was obtained as the sequence of the RR time intervals; the frequency analysis was performed by means of an autoregressive time-variant model, and spectral parameters able to quantify the sympatho-vagal balance (LF and HF power and their ratio LF/HF) have been obtained on a beat-to-beat bases. All the selected patients had an infero-postero-lateral infarction, and different responses to the thrombolytic therapy were identified: reperfusion and no reperfusion. The behaviour of the spectral parameters differs in subject with reperfusion and with no reperfusion