Rapid recovery of baroreceptor reflexes in acute myocardial infarction is a marker of effective tissue reperfusion.

Baroreflex sensitivity (BRS) measured several days after myocardial infarction (MI) is a powerful predictor of cardiovascular mortality. No information is available on BRS in the early hours of MI. The possibility to reliably assess BRS in the acute phase of MI and its clinical correlates were evaluated in 45 patients treated with primary percutaneous coronary intervention (pPCI). BRS (sequence method) was assessed 1, 3, 6, and 12 h after PCI. ST resolution (STRes) was considered present if ST had decreased ≥70 % 3 h after PCI. BRS was 10.7 ± 6.2 1 h after PCI; at 12 h it was 15.4 ± 5.2 and 8.4 ± 4.8 ms/mmHg in patients with and without STRes, respectively (p < 0.001). STRes was an independent predictor of 12 h BRS (p = 0.005) and of 1-12 h BRS difference (p = 0.002). BRS can be reliably assessed in the first hours of MI; it shows a rapid recovery in patients with STRes and a significant depression in patients without STres.