• Myocardial Infarction
• Prevention & Screening

The importance of using risk screening assessment tools to guide therapeutic management of patients cannot be underestimated [Scruth EA et al. Clin Nurse Spec 2012]. Avonello A. Maynard, MD, Queen Elizabeth Hospital, St. Michael, Barbados, presented a comparison and validation of Thrombolysis in Myocardial Infarction (TIMI), Global Registry of Acute Coronary Events (GRACE), and front-door risk scores in an acute coronary syndrome (ACS) population in Barbados.

Risk stratification identifies ACS patients at greatest risk of recurrent ischemic events who might benefit from further assessment and treatment. Several risk scores can be used to determine in-hospital and short-term survival [Scruth EA et al. Clin Nurse Spec 2012]. According to Dr. Maynard, the TIMI and GRACE risk scores are widely applied but present practical problems for ease of use in Barbados.

Ideal risk scores, he said, are simple, efficient, and inexpensive. Among those with unstable angina (UA)/NSTEMI, Antman et al. [JAMA 2000] demonstrated that the TIMI risk score is a simple prognostication scheme that categorizes a patient's risk of death and ischemic events and provides a basis for therapeutic decision making.

Morris et al. [Heart 2006] found that in an undifferentiated chest pain population, the TIMI score for unstable angina without the troponin component (ie, the front-door score) is rapidly obtainable on patient arrival but not as sensitive or specific as the full score. Although the front-door score clearly identifies risk and can inform triage decisions before results of troponin assays are available, the full TIMI risk score for UA accurately stratifies risk of death and ischemic events based on a simple 7-point scale [Antman EM et al. JAMA 2000].

The TIMI risk score for STEMI consists of a 14-point scale based on history, physical examination, and presentation. Developed to be a convenient bedside clinical risk score for predicting 30-day mortality in fibrinolytic-eligible patients, it captures the majority of prognostic information offered by a full logistic regression model [Morrow DA et al. Circulation 2000].

Singh et al. [Circulation 2002] found that in a community-based cohort, comorbidity and ejection fraction convey important prognostic information that should be included in approaches for stratifying risk after MI. They found that in this population, the Predicting Risk of Death in Cardiac Disease Tool (PREDICT) score had greater discriminant accuracy than the TIMI scores for STEMI and NSTEMI.

Fox et al. [BMJ 2006] report that the GRACE risk prediction tool includes variables that are readily available to clinicians—even in smaller community hospitals—and provides a novel and widely applicable method of assessing the cumulative 6-month risk of death and death or MI across the spectrum of patients with ACS admitted to hospitals.

According to Dr. Maynard, the simpler front-door score may be ideal for the UA/NSTEMI population in Barbados. His research team attempted to compare and validate the TIMI, GRACE, and front-door scores in a Caribbean population for patients with ACS (Tables 1 and 2) and demonstrate applicability in a clinical setting with improved outcomes.

• © 2012 MD Conference Express®