The prevalence of use of beta-blockers in secondary prevention of myocardial infarctions in patients hospitalized

1Institute of Epidemiology and biostatistics, Faculty of Medicine, University of Sarajevo, BiH

2Clinic for heart disease and rheumatism, Sarajevo  

Use of beta-blockers, if for no contraindications, within seven days after myocardial infarction and the continuous application of a period of several months to three years has shown in many randomized clinical trials the reduction of total mortality, reinfarction, sudden cardiac death for 20-30 %.

Historical overview of the major clinical trials with beta-blockers

1982 The Beta-Blocker Heart Attack Trial (BHAT).

(propranolol significantly reduced overall mortality by 26% compared with placebo. (2)

1984 edition of Braunwald's Heart Disease

The mid-1990, the percentage of patients receiving beta-blockers after myocardial infarction was still just 34% in one major study and 38% in another.(2)

1996 American College of Cardiology and the American Heart Association -first

recommendations the use of beta -blockers in the absence of contraindications for management of acute myocardial infarction.(4)

MERIT-HF (Metoprolol Controlled-Release/Extended-ReleaseRandomized Intervention Trial in Heart Failure (reduction of all causes by 34%, 40-50% of sudden cardiac death). (4)

CAPRICORN (Carvedilol Post Infarkt Survival Control in LV Dysfunction) reduction in mortality of all causes of death by 23%, 8% lower hospitalization of all diseases, 14% less hospitalization for cardiovascular diseases.

The 2001 American Heart Associatin and American College of Cardiology (AHA / ACC) emphasize the importance of application of beta blockers and give the main guidelines for the treatment of myocardial infarction.

Use of Beta-Blocker Treatment after Myocardial Infarction, 1996–2005. U.S.Data are from the National Committee for Quality Assurance.

Source: Lee T. H. Eulogy for a Quality Measure. N Engl J Med(serial on the Inernet). 2007 Sept [cited 2007 Sept 20]; Volume 357:1175-1177 [about 3p.] Available from: http://content.nejm.org/cgi/content/full/357/12/1175 (10.04.2010.)

The aim of this study was to review medical records of hospitalized patients with acute myocardial infarction (AMI) to determine the prevalenc of use beta-blockers in the treatment of secondary prevention of myocardial infarction in relation to patient age, left ventricular ejection fraction and day of inclusion in the therapy.

Materials and metodes

Medical records of hospitalized patients hospitalized in Clinic of cardiovascular diseases KCUS in the period 01.January-3.June 2005.

In cross-sectional study included patients with ST and non-ST AMI.

Data were collected from the patients history, echocardiographic findings of heart and temperature charts with emphasis on the use of beta-blockers (atenolol, metoprolol, and carvedilol).

Prevalence of patients with AMI 01. January-30.June 2005. Cardivascular Clinic and rheumatism KCUS

Mortality of patients with AMI in hospital (01.January-30.June 2005)

The prevalence of patients with AMI in relation to gender

The mean age of 196 patients was 62.5 (SD±11,6) years

Prevalence of patients with AMI in relation to age group and gender

45.9% over 65 + years,

Prevalence of patients with AMI relation gender and age <65 and 65+

Statistically significant higher representation of women over the age of 65 + years ( Hi215,97; p<0,05).

Prevalence of risk factors in patients with AMI

Prevalence of the application beta-blockers, along with other standard treatment* for patients with AMI

Prevalence of the application beta-blockers within seven days after MI, along with other standard treatment* for patients with AMI

Prevalence of beta-blockers (atenolol, metoprolol, carvedilol)

Prevalence of the application beta-blockers, relation to age group

In relation to the age group of patients beta-blockers were significantly less applied in patients over 65 + years ( Hi213,669; p<0,05).

Prevalence of the application beta-blockers, relation to left ventricular ejection fraction (LVEF)

No statistically significant differences in the use of beta blockers were found (EF <35% in 64.3%, EF 35-50% in 68.4% and EF >50 in 63.2%; Hi2 0.539, p<0.05).

Conclusion

Beta-blockers within seven days after AMI were applied in 63.8% of patients, no significant differences in the application in relation to the left ventricular ejection fraction (EF), but with significantly lower use in elderly patients 65 + years.

References:

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