PURPOSE: Primary percutaneous coronary intervention (pPCI) has become the preferred reperfusion strategy in patients with ST-elevation myocardial infarction and cardiogenic shock (CGS) . Early identification of patients at risk for developing CGS allows rapid decision-making to determine reperfusion and transportation to a PCI centre. The aim of this analysis was to evaluate shock index as a marker for patients at risk of CGS.
METHODS: A total of 644 consecutive patients (73% male) with acute myocardial infarction with ST elevations, included in the registry of primary and rescue PCI of Cardiocenter University Hospital within the period of the years 2000 and 2001, were retrospectively analyzed. The mean age was 63 years (range 21–91 years), diabetes was present in 27% patients, 50% of patients had hypertension. Primary PCI was performed in 92% patients, 8% patients underwent rescue PCI (after the failure of thrombolysis). Parameter shock index (SI) was defined as the ratio of heart rate and systolic blood pressure at hospital admission.
RESULTS: In-hospital mortality of the whole group was 9.5% (61 patients) and it occured mostly among patients admitted in cardiogenic shock (15%). Mortality in the group without cardiogenic shock was 1.8%. Shock index (OR 81.26, 95% CI: 9.76–676.51, P<0,001), age (OR 1.17, 95% CI: 1.08–1.26, P<0.001) and diabetes (OR 4.94, 95% CI: 1.44–16.97, P<0.011) were independent predictors of mortality. In the group of patients with SI ≥0.8 20.3% died, whereas in the group with SI <0.8 only 4% of the patients died (p <0.01).
CONCLUSION: The proposed clinical parameter “shock index” correlates with patients’ prognosis and could be therefore used as a simple indicator of mortality risk of acute myocardial infarction.
CLINICAL IMPLICATIONS: The simplicity of this proposed index makes its use accessible in the large-scale clinical practice for stratification of acute myocardial infarction risk during the first contact with the patient.
DISCLOSURE: Dana Bilkova, No Financial Disclosure Information; No Product/Research Disclosure Information