High-grade atrioventricular block in patients with acute myocardial infarction. Insights from a contemporary multi-center survey.

High-grade atrioventricular block (HAVB) is a frequent complication of acute myocardial infarction (AMI) and is associated with increased morbidity and mortality. We aimed to evaluate the incidence, predictors, and prognostic significance of HAVB in a contemporary cohort of patients with AMI, in the recent era of early reperfusion. Patients with acute coronary syndromes (n=11,487) during the years 2000-2010 were included. Patients were divided into two groups: with HAVB (n=308, 2.7%) and without HAVB (n=11,179, 97.3%). The incidence of HAVB decreased from 4.2% in 2000 to 2.1% in 2010 (p for trend<0.01). Patients with HAVB were more likely to develop in-hospital complications. Independent predictors of developing HAVB were older age, ST-elevation myocardial infarction (STEMI), smoking and Killip class≥2 on admission. 30-day and 1-year mortality rates were significantly higher in the HAVB as compared to the non-HAVB group (24% vs. 4.9%, p<0.01, 33.5% vs. 10%, p<0.01, respectively). Multivariable logistic regression analysis revealed that, HAVB was associated with increased 30-day (OR - 3.97; 95% CI - 1.96-8.04) and 1-year mortality risk (HR - 2.02; 95% CI - 1.3-3.1). Similar estimates were obtained for STEMI and non-STEMI (NSTEMI). In conclusion, although the incidence of HAVB decreased over the last decade, the associated morbidity and mortality are still high in these patients despite early reperfusion therapy.