Does early invasive therapy reduce mortality more than conservative treatment in patients with non-ST segment elevation acute coronary syndromes?

Early invasive therapy decreases long-term mortality rates and short-term rehospitalization rates in patients with non-ST segment elevation acute coronary syndrome (ACS) without increasing acute myocardial infarction (MI) likelihood. If a hospital with a catheterization laboratory is available, send patients to that hospital. (LOE = 1a)

Bavry AA, Kumbhani DJ, Rassi AN, Bhatt DL, Askari AT. Benefit of early invasive therapy in acute coronary syndromes. J Am Coll Cardiol 2006;48:1319-1325.  [PMID:17010789]

Meta-analysis (randomized controlled trials)

Unknown/not stated

Inpatient (any location)

Research is consistent that early invasive therapy, such as bypass grafting or percutaneous intervention, for non-ST-segment elevation ACS improves overall cardiac outcomes. However, MI may be more common immediately following these procedures, and this meta-analysis combined recent trials to determine the benefit of early invasive therapy on mortality rates, MI, and recurrent unstable angina. Since studies of early invasive therapy are large and well-known, the authors used a relatively weak method of searching for relevant research. They limited the studies in their analysis to interventions that included common adjunctive treatment, including the use of glycoprotein IIb/IIIa inhibitors and/or clopidogrel (Plavix) or ticlopidine (Ticlid). They excluded studies that evaluated patients with ST-segment elevation MI and studies using fibrinolytic drugs. Three reviewers independently abstracted the data from the studies. The final analysis included results from 7 studies enrolling a total of 8375 patients. Mortality was 5.4% over the 1month to 60 months follow-up of the studies. The authors used intention-to-treat analysis, since only 71% of patients assigned to invasive treatment actually received it, and 46% of patients in the conservative treatment group eventually underwent invasive treatment over the average 2 years of follow-up. Results were homogeneous and there was no evidence of publication bias. Mortality due to any cause, over an average of 2 years, was lower in the immediate invasive treatment group: 4.9% vs 6.5% (P = .001). Using immediate invasive treatment prevents 1 additional death for every 62 patients who receive it (95% CI, 42 - 154). This difference did not show up until more than 24 months of follow-up. Similarly, the rate of nonfatal MI was less with immediate intervention than with conservative treatment (number needed to treat [NNT] = 66; 39 - 275). This difference was not significant until more than 2 years of follow-up, but the rate did not increase in the short-term, either. Rates of hospitalization for recurrent unstable angina was lower with early invasive treatment and occurred in the first year (NNT = 11; 10-13).