['Modulation of the autonomic tone may contribute to the positive clinical effects of reperfusion of the ischemic zone after acute myocardial infarction (AMI). Little information exists about the effects on the sympathovagal balance of the early reopening of the vessel achieved by means of primary coronary angioplasty (PTCA). Even less is known on the autonomic effects of rehabilitation in patients undergoing PTCA.', 'We performed spectral analysis of the RR interval variability during 15 min of ECG in resting conditions in 51 patients (47 males, 4 females, mean age 55 +/- 6 years) 2-3 weeks after a first anterior AMI, and after 8 weeks of rehabilitation with physical training. The ratio between the low- and high-frequency (LF/HF) components of each autospectrum was used to describe the sympathovagal balance. Patients were divided into three groups: group 1 (n = 26, primary PTCA/stenting); group 2 (n = 11, recombinant tissue-type plasminogen activator); group 3 (n = 14, no reperfusion). Treatment was similar in the three groups and was maintained during the whole rehabilitation period. Results. Before rehabilitation, group 1 showed an adrenergic activation that was more blunted than that observed in groups 2 and 3. This activation was maximal in those patients with the shortest delay before the procedure. Cardiovascular rehabilitation modulated the LF/HF ratio in all groups.'] Are original articles primary coronary angioplasty and subsequent cardiovascular rehabilitation linked to a favorable sympathovagal balance after a first anterior myocardial infarction?