[Prognostic significance of advanced atrioventricular block in patients with acute myocardial infarction]

Thirty-year trends (1975-2005) in the magnitude and hospital death rates associated with complete heart block in patients with acute myocardial infarction: a population-based perspective

BACKGROUND

The contemporary magnitude and prognostic implications of complete heart block (CHB) in patients with acute myocardial infarction (AMI) are unknown. As part of a community-based study of patients hospitalized with AMI in the Worcester, MA, metropolitan area, changes over time in the incidence rates of CHB complicating AMI and the prognostic impact of CHB on short-term survival were examined.

METHODS

The study population consisted of 13,663 residents of the Worcester metropolitan area who were hospitalized with AMI at all greater Worcester medical centers during 15 annual periods between 1975 and 2005.

RESULTS

The average age of the hospitalized study sample was 69 years, and 58% were men. The overall proportion of patients with AMI who developed CHB was 4.1%. The incidence rates of CHB complicating AMI declined appreciably over time, with the greatest decline in these incidence rates occurring during the most recent years under study. In 2005, 2.0% of patients hospitalized with AMI developed CHB compared to 5.1% in the initial study year of 1975. Patients with AMI who developed CHB had higher inhospital death rates (43.2%) than did those who did not develop CHB (13.0%) (P < .001). The hospital death rates associated with CHB declined appreciably over time, particularly during the most recent years under study. Several patient characteristics were associated with an increased risk for developing CHB during hospitalization for myocardial infarcation.

CONCLUSIONS

Our findings indicate recent encouraging declines in the incidence rates of CHB complicating AMI and improving trends in the hospital prognosis of these patients.

Bloqueo auriculoventricular en la angina inestable. Resultados del registro ARIAM

OBJECTIVE

Describe the frequency of high degree atrioventricular block (HDAVB) in patients with unstable angina (UA), analyze the variables associated with their appearance and evaluate whether HDAVB is independently associated with increased mortality or increased length of ICU stay.

DESIGN

Retrospective descriptive study of patients with UA included in the ARIAM registry.

SETTING

ICUs from 129 hospitals in Spain.

PATIENTS

From June 1996 to December 2003 a total of 14,096 patients were included in the ARIAM registry with a diagnosis of UA.

MAIN VARIABLES OF INTEREST

Variables associated with the development of HDAVB, variables associated with the mortality of patients with UA, variables associated with the length of ICU stay of patients with UA.

RESULTS

HDAVB frequency was 1%. Development of HDAVB was independently associated with the Killip classification and the presence of sustained ventricular tachycardia or ventricular fibrillation. Crude mortality of patients was significantly increased when HDAVB was present (9% versus 1%, p < 0,001). When adjusted for other variables, HDAVB was not associated with increased mortality. Development of HDAVB in patients with UA was independently associated with an increase in the length of ICU stay (adjusted odds ratio 1.89: 95% confidence interval: 1.33-5.69).

CONCLUSIONS

Patients with UA complicated with HDAVB represent a high-risk population with an increased ICU stay.