Myocardial infarction: inferior: complete heart block and heart failure increased the risk of dying.

Clinical bottom line (level 1b)

  1. One in six patients with an inferior myocardial infarction were dead within 12 months.
  2. Patients were at increased risk of dying if they
    • developed heart failure
    • had heart failure before admission
    • developed complete heart block
    • were aged > 70
Moreno et al: Revista Espanola Cardiologica 1997; 50 (6): 397-405
Expires October 2003

The study

Retrospective cohort study with objective outcomes, adjusted for confounding factors, not validated in an independent set of patients.

Setting: 3 acute hospitals, Spain

605 patients (aged mean 63, 78% male) with inferior myocardial infarctions (based on at least 2 of 30 minutes of chest pain, CK rise more than twice normal and q waves > 0.04 s in leads II, III, aVF)

Factors studied:
  • age, sex, previous MI, previous heart failure, diabetes mellitus, maximum elevation of CK, bundle branch block, heart failure during hospital stay, Killip class
  • complete heart block diagnosed on ECG if the atrial rhythm was faster than the ventricular
  • previous congestive heart failure
  • aged > 70
  • Killip class > 1 during hospital stay


    • All patients were thrombolysed unless contraindicated (60%).

    Multivariate regression analysis performed on prognostic factors.

    97% followed for 12 months
    Outcomes studied:
  • death

    • The evidence

    outcome time to outcome number of patients/total number %
    (95% CI)    		 NNF
    (95% CI)
    death 12 months 104/605 17%
    (14% to 20%)    		 6
    (5 to 7)

    prognostic factor for
    death     		time to outcome control rate (%) adjusted OR
    (95% CI)    		 NNF+
    (95% CI)
    complete heart block 12 months 90/548
    (16.4%)     		2.7
    (1.3 to 5.5)     		5
    (3 to 26)
    previous congestive heart failure 12 months 104/605
    (17.2%)     		5.32
    (2.16 to 13.1)     		3
    (2 to 7)
    aged > 70 12 months 104/605
    (17.2%)     		6.61
    (3.67 to 11.9)     		2
    (2 to 4)
    Killip class > 1 during hospital stay 12 months 104/605
    (17.2%)     		13.5
    (7.29 to 24.8)     		2
    (2 to 2)

    Comments

    1. 57 patients developed complete heart block (9.4%, 95% CI: 7.1% to 11%)

    Citation

    1. Moreno AM, Tomas JG, Alberola AG, et al: significacion pronostica del bloqueo auriculoventricular completo en pacientes con infarto agudo de miocardio inferior. Un estudio en la era trombolitica. Revista Espanola Cardiologica 1997; 50 (6): 397-405
    Contributor: Chris Ball and Clare Wotton, October 1999
    Reviewer:

    Clinical Question.
    Patient inferior MI
    Intervention or Exposure risk factors
    Outcome death