A new post-PCI scoring system for in-hospital mortality in STEMI patients.

OBJECTIVE

To develop a scoring system for predicting in-hospital mortality among ST-elevation myocardial infarction (STEMI) patients submitted to percutaneous intervention (PCI) on intensive cardiac care unit admission by using early and readily available clinical, angiographic and laboratory data.

DESIGN

Prospective monocentric observational study in which we used discriminant analysis to develop a final scoring system, with prospective validation.

SETTING

Intensive cardiac care unit in Florence, a tertiary center.

POPULATION: Five hundred and fifty-eight unselected patients with STEMI (group A) consecutively admitted from 1 January 2004 to 31 December 2006. A control group (group B) comprising 183 STEMI patients admitted from 1 January 2007 to 30 September 2007.

MAIN OUTCOMES AND MEASURES: In-hospital death.

RESULTS

In group A the discriminant variables were admission Killip class, admission lactic acid, admission ejection fraction, admission troponin I (TnI), admission hemoglobin (Hb), ST-segment reduction post-PCI, systolic blood pressure on admission and chronic renal failure. We elaborated a scoring system, the Florence admission STEMI risk score, which shows an agreement of 95.7% between the observed and the estimated outcome on a statistical basis in the survival and death subgroups. We applied this score to group B (C statistics = 0.986).

CONCLUSION

The Florence admission STEMI risk score incorporates anamnestic (chronic renal failure), laboratory (lactic acid, TnI and Hb), procedural and post-procedural data (ST-segment reduction post-PCI, Killip class) as well as data strictly related to infarct size (ejection fraction, TnI). This scoring system is likely to be a simple and practical tool at the bedside for risk evaluation in patients with STEMI submitted to primary PCI.