Atrioventricular block in the acute phase of ST-elevation myocardial infarction

Introduction The occurrence of an atrioventricular block (AVB) in the acute phase of ST-elevation myocardial infarction (STEMI) is a classic and often reversible complication, especially in the inferior territory. Objective To describe the AVBs observed in the MIRAMI registry, their predictive factors, and their prognostic value. Method Among the 1388 patients admitted for (STEMI) included in the Monastir Acute Myocardial Infarction (MIRAMI) registry, we studied patients who presented a recent AVB during hospitalization. The characteristics related to the occurrence of these AVBs as well as their correlated prognosis are described. Results AVB occurred in 131 (9.4%) patients with a mean time to onset of 19±13hours. Predictive factors for the occurrence of AVB in STEMI patients were: creatinine≥130μmol/L, OR=2.69, anaemia (P=0.002, OR=1.9 for haemoglobin<12g/dL) and inferior location (P<0.001, OR=2.46). Neither advanced age nor successful reperfusion was found to be a predictive factor. In-hospital mortality was increased (22% vs. 8.2% P<0.001). As well as a cardiogenic shock (P<0.001) and ischemic recurrence (P=0.005). AVB was the direct cause of death in only 3 (2%) patients. Conclusion The occurrence of AVB is common in inferior STEMI, anemia, and renal failure. It is independent of the strategy or outcome of reperfusion and the age of the patient. The AVB in the context of STEMI is associated with higher morbidity and mortality without being the direct cause.