Angina: unstable: a number of clinical and ECG features predict adverse outcomes

Clinical bottom line (level 2a)

  1. In patients with chest pain suggestive of cardiac ischaemia, the following features increase the risk of adverse outcomes
    • increasing age
    • male sex
    • cardiovascular risk factors
    • prior myocardial infarction
    • signs of heart failure
    • signs of ischaemia on ECG
  2. In patients with unstable angina, the following features increase the risk of adverse outcomes
    • increasing age
    • male sex
    • cardiovascular risk factors
    • prior ischaemic heart disease
    • recurrent or rest pain
    • signs of heart failure
    • signs of ischaemia on ECG
    • maximal antianginal therapy
    • use of nitrates
Heidenreich et al: AHRQ Publication No. 01-E001 2000; 31 : -
Expires March 2004

The study

Systematic review of all prognostic studies of
  • Patients: chest pain suspected to be ischaemic or diagnosed unstable angina in emergency department or hospital
  • Intervention: clinical and ECG features on presentation or within first 24 hours
  • Outcome: death, myocardial infarction, urgent revascularisation, cardiac complications (arrhythmia, heart failure, cardiac arrest)

    Articles found in English using Medline, 1966 to 1998 (search terms: Chest pain, angina pectoris, unstable angina, variant angina, vasospastic angina, or acute coronary syndrome combined with the terms risk, stratification, prognosis, outcome, and multivariate analysis ) and reviewing the bibliographies of retrieved articles

    Selection criteria: by 2 independent reviewers - see above and below for details
    Appraisal criteria: by 2 independent reviewers - details not given
    Articles excluded if:
    • no multivariate analysis of clinical and/or ECG predictors of adverse events
    • quantitative results with measures of significance (e.g., p value, standard error) in the form of regression estimates, relative risks, odds ratios, or rate ratios
    • non-English language
    • clinical and electrocardiographic variables assessed on initial presentation in the emergency department or within the first 24 hours of admission to the hospital not evaluated
    • assessed the importance of ST elevation on outcomes or characteristics about only patients with ST elevation were excluded


    18 studies found - 8 on 20199 patients with chest pain suggestive of ischaemia and 10 on patients with a diagnosis of unstable angina

    The evidence

    • Prognostic factors independently associated with adverse outcomes in patients with chest pain suggestive of cardiac ischaemia
      • increasing age
      • male sex
      • prior myocardial infarction
      • diabetes
      • congestive heart failure
      • hypertension
      • smoking
      • typical angina
      • increasing duration of pain
      • congestive heart failure on admission
      • low blood pressure on admission
      • ST depression
      • ST-T changes
      • any evidence of ischaemia
      • shock after admission
      • third heart sound
    • Prognostic factors independently associated with adverse outcomes in patients diagnosed with unstable angina
      • increasing age
      • male sex
      • prior myocardial infarction
      • diabetes mellitus
      • hypertension
      • absence of prior revascularisation
      • prior CABG
      • prior congestive heart failure
      • prior angina
      • postinfarction angina
      • rest pain after admission
      • rest angina within 48 hours before admission
      • congestive heart failure on presentation
      • tachycardia on presentation
      • low blood pressure on presentation
      • ST depression > 0.1 mV
      • ST deviation 0.5 mV or more
      • evolutionary T-wave changes
      • left bundle-branch block
      • no prior beta-blocker therapy
      • requiring iv nitrates
      • recurrent severe chest pain
      • maximal antianginal therapy
      • thrombolysis in prior week
      • other major illness
      • nitrate use in week before admission

    Comments

    1. Many studies failed to address all possible clinical and ECG prognostic factors and there was substantial heterogeneity in study design, enrollment criteria, factors and outcomes studied, length of followup, and methods of analysis. Consequently data could only be reported semi-quantitatively.
    2. By limiting the search to Medline and the English language important articles may have been missed.
    3. Studies were often too small to assess adequately multiple prognostic factors.
    4. The authors note that no clinical prediction rule has yet successful combined these factors.

    Citation

    1. Heidenreich PA, Go A, Meslop KA, et al: Prediction of risk for patients with unstable angina. Evidence Report/Technology Assessment No. 31 (prepared by the UCSF-Stanford Evidence-based Practice Center under Contract No. 290-97-001. AHRQ Publication No. 01-E001 2000; 31 : -
    Contributor: Chris Ball, March 2002
    Reviewer:

    Clinical Question.
    Patient chest pain suspicious of cardiac ischaemia or unstable angina
    Intervention or Exposure clinical and ECG features
    Outcome death, myocardial infarction, cardiac complications
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