Clinical Investigation
Acute Ischemic Heart Disease
Ventricular arrhythmias after acute myocardial infarction: A 20-year community study

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Background

Although myocardial infarction (MI) severity is declining, the occurrence of ventricular arrhythmia (VA) after MI and its effect on outcome is unknown. This study was undertaken to examine the frequency and timing of VA and the effect of VA on mortality after MI.

Methods

Myocardial infarctions recorded between 1979 and 1998 were validated. Baseline characteristics, occurrence of VA, and survival were determined. Ventricular arrhythmias were categorized as primary ventricular fibrillation (VF), nonprimary VF, and ventricular tachycardia (VT). Logistic regression was used to analyze associations between VA and baseline characteristics. Temporal trends were assessed with the Mantel-Haenszel χ2. Survival was analyzed with the Kaplan-Meier method. Proportional hazards regression was used to examine the association between death and occurrence of VA.

Results

Among 2317 persons with incident MI, 7.5% experienced VA (3.6% nonprimary VF, 2.1% primary VF, 1.8% VT). Ventricular arrhythmia–associated factors were younger age, female sex, higher Killip class, ST elevation, and atrial fibrillation. Ventricular arrhythmias were associated with increased risk of death at 30 days.

Conclusion

Ventricular arrhythmias after MI are relatively common, particularly among persons with more severe MI and no prior history of coronary disease. Over time, the incidence of VF declined, whereas VT did not change. Ventricular arrhythmia after MI was associated with a 6-fold increase in morality. Thus, identification of high-risk MI survivors and prevention of VA could markedly improve outcomes. Further studies are needed to determine the cause of the shift in distribution of VA subtype.

Section snippets

Study setting

This study was conducted with approval from the medical center's institutional review board. The characteristics of the region's population (a county in the upper Midwest) are similar to those of the US white population. Epidemiological studies are possible because the county is relatively isolated, and a few providers deliver nearly all health care to local residents. Each medical provider uses a comprehensive medical record system in which the details of every encounter are entered and can be

Characteristics of the MI cohort

Between 1979 and 1998, 2317 persons (43% women, mean age 67.4 ± 14.3 years) were hospitalized with incident MI (Table I). Risk factors were prevalent, with hypertension and smoking present in more than half the cohort. Twenty percent of subjects had diabetes, and the mean body mass index was 27.1 ± 5.8 kg/m2. Most patients (65%) were in Killip class I, and 16% of patients were treated with β-blockers before admission. Forty-three percent of the cohort members had ST-elevation MI (STEMI) and 57%

Discussion

In this geographically defined cohort, 7% of patients developed VA after incident MI, occurring mostly within the first 48 hours. Over time, the occurrence of all VA declined slightly because of a relative shift in the distribution of the types of VA. Although the incidence of nonprimary VF decreased, that of primary VF and VT remained stable. Characteristics associated with the occurrence of VA include younger age, female sex, AF, STEMI, and higher Killip class and the inaugural nature of the

Conclusions

In this geographically defined MI incidence cohort, 7% of patients developed VA after incident MI, occurring mostly within the first 48 hours. During the 2 decades studied, the occurrence of VA after MI declined slightly, with a relative shift in the respective distribution of the types of VA. Ventricular arrhythmias were more likely to occur among individuals without a history of cardiac disease and with a higher Killip class. All VAs, including primary VF, are associated with a marked

References (57)

  • M.E. Charlson et al.

    A new method of classifying prognostic comorbidity in longitudinal studies

    J Chronic Dis

    (1987)
  • A. Volpi et al.

    Incidence and short-term prognosis of late sustained ventricular tachycardia after myocardial infarction

    Am Heart J

    (2001)
  • R.A. Josephson et al.

    Effect of age on postmyocardial infarction ventricular arrhythmias

    Am J Cardiol

    (1995)
  • S. Al-Khatib et al.

    Sustained ventricular arrhythmias and mortality among patients with acute myocardial infarction

    Am Heart J

    (2003)
  • G. Tofler et al.

    Prognosis after cardiac arrest due to ventricular tachycardia or ventricular fibrillation associated with acute myocardial infarction

    Am J Cardiol

    (1987)
  • A. Volpi et al.

    One-year prognosis of primary ventricular fibrillation complicating acute myocardial infarction

    Am J Cardiol

    (1989)
  • J. Hellermann et al.

    Heart failure after myocardial infarction: a review

    Am J Med

    (2002)
  • H. Tunstall-Pedoe et al.

    Contribution of trends in survival and coronary event rates to changes in coronary heart disease mortality

    Lancet

    (1999)
  • C. Naylor et al.

    Population-wide mortality trends among patients hospitalized for acute myocardial infarction

    J Am Coll Cardiol

    (1994)
  • L.J. Melton

    History of the Rochester epidemiology project

    Mayo Clin Proc

    (1996)
  • A.D. White et al.

    Community surveillance of coronary heart disease in the Atherosclerosis Risk in Communities (ARIC) study

    J Clin Epidemiol

    (1996)
  • J. Perschbacher et al.

    Evidence-based therapies for myocardial infarction: secular trends and determinants of practice in the community

    Mayo Clin Proc

    (2004)
  • B.S. Crenshaw et al.

    Atrial fibrillation in the setting of acute myocardial infarction

    J Am Coll Cardiol

    (1997)
  • P. Gheeraert et al.

    Preinfarction angina protects against out-of-hospital ventricular fibrillation in patients with acute occlusion of the left coronary artery

    J Am Coll Cardiol

    (2001)
  • R. Myerburg et al.

    Sudden cardiac death

    Circulation

    (1992)
  • D. Chiriboga et al.

    Temporal trends in the incidence and case-fatality rates of primary ventricular fibrillation complicating acute myocardial infarction

    Circulation

    (1994)
  • A. Volpi et al.

    Incidence and prognosis of secondary ventricular fibrillation in acute myocardial infarction

    Circulation

    (1990)
  • M. Ruiz-Bailen et al.

    Ventricular fibrillation in acute myocardial infarction in Spanish patients

    Crit Care Med

    (2003)
  • Cited by (0)

    This study was supported in part by grants AR30582 and HL59205 from the Public Health Service and the National Institutes of Health. Dr Roger is an established investigator of the American Heart Association.

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