Myocardial infarction: shock, age over 70 and right ventricular infarction increased risk of in-hospital mortality.

Clinical bottom line (level 1b)

  1. Patients with an inferior myocardial infarction were at an increased risk of in-hospital mortality if they had: shock at admission; right sided ventricular infarction (V4R ST-segment elevation of 0.1 mV or more); aged over 70.
  2. Nearly a half of patients had a major complication in-hospital.
  3. Patients were at an increased risk of major complications if they had shock at admission or ST-segment elevation of 0,1 mV or more.
Zehender et al: New England Journal of Medicine 1993; 328 (14): 981-988
Expires March 2003

The study

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

Setting: general hospital, Germany

200 patients (aged range 35 to 91 years; mean 62, 77% male) acute inferior myocardial infarction (typical chest pain lasting for> 30 minutes, ST-segment elevation > or =0.1 mV in two or more leads and an increase in serum creatine kinase level to >twice the normal value less than 24 hours after admission)


Multiple logistic regression was used to adjust for confounding factors.

100% followed for hospitalisation
Outcomes studied:
  • mortality
  • major complications (cardiogenic shock, ventricular fibrillation, sustained ventricular tachycardia, complete AV block, severe bradycardia, requirement for pacing or myocardial rupture, tamponade)

    • The evidence

    outcome time to outcome number of patients/total number %
    (95% CI)
    mortality hospitalisation 38/200 19.0%
    (13.6% to 24.4%)
    major complications hospitalisation 94/200 47.0%
    (40.1% to 53.9%)

    prognostic factor for
    mortality     		time to outcome adjusted RR
    (95% CI)    		 NNF+
    (95% CI)
    shock at time of admission hospitalisation 11.4
    (3.48 to 37.3)     		1
    (0 to 2)
    ST-segment elevation > or = 0.1 mV in lead V 4R hospitalisation 7.70
    (2.60 to 23.0)     		1
    (0 to 3)
    age >70 hospitalisation 3.19
    (1.11 to 9.14)     		2
    (1 to 48)
    thrombolytic therapy hospitalisation 0.29
    (0.10 to 0.86)     		-7
    (-38 to -6)

    prognostic factor for
    major complications     		time to outcome adjusted RR
    (95% CI)    		 NNF+
    (95% CI)
    shock at time of admission hospitalisation 6.09
    (1.82 to 20.4)     		1
    (0 to 6)
    ST-segment elevation > or =0.1 mV in lead V 4R hospitalisation 4.70
    (2.40 to 9.00)     		1
    (1 to 4)

    Comments

    1. Numbers needed to follow are over-estimated due to the control rate, which is the overall rate of the patients.

    Citation

    1. Zehender M, Kasper W, Kauder E, et al: Right ventricular infarction as an independent predictor of prognosis after acute inferior myocardial infarction. New England Journal of Medicine 1993; 328 (14): 981-988
    Contributor: Clare Wotton and Bob Phillips, February 2000
    Reviewer:

    Clinical Question.
    Patient acute inferior myocardial infarction
    Intervention or Exposure right ventricular infarction
    Comparison not right ventricular infarction
    Outcome mortality