Introduction: Previous studies have evaluated the prognostic impact of early invasive strategies in the management of non-ST elevation acute coronary syndromes (NSTEACS). There is, however, conflicting evidence about the advantages of such an approach. In some studies the benefits are dependent on gender or age, while time to angiography varies between studies.
Methods: We performed a retrospective analysis of 222 patients admitted with NSTEACS between 1/1/2004 and 12/31/2004. The patients initially received intensive medical therapy and were divided into three groups according to the subsequent approach. In the early invasive strategy group (EIS; n = 62), angiography was performed in the first 48 hours; in delayed invasive strategy (DIS; n = 97), angiography was routinely performed but postponed beyond the first 48 hours; in the conservative strategy group (CS; n = 63), catheterization was performed only in cases of refractory angina or evidence of ischemia in non-invasive tests. We evaluated the occurrence of death or hospitalization due to cardiac cause during a mean follow-up of 549 days.
Results: The patients' mean age was 64.6 +/- 11.7 years and 66.7% were male. CS patients were older than the others (60.6 +/- 10.3 [EIS]; 63.2 +/- 11.2 [DIS]; 70.6 +/- 11.5 [CS]; p < 0.0005). The prevalence of cardiovascular risk factors was similar in the three groups. Ejection fraction (EF) at discharge was lower in the CS group (51.2% +/- 9.5; 51.3% +/- 7.4; 44.5% +/- 11.4; p < 0.0005). The primary endpoint occurred in 9.6%, 16.4% and 41.3% in the EIS, DIS and CS groups respectively. On multivariate analysis, after adjustment for age, EF and troponin I elevation, CS maintained the association with the endpoint (OR 5.17; 95% CI 1.64-16.32), while EF > 40% was inversely related to the endpoint.
Conclusion: A conservative approach to NSTEACS was, in our population, associated with a worse prognosis. Delaying cardiac catheterization beyond the first 48 hours had no prognostic impact.