Impact of Prehospital Thrombolysis for AcuteMyocardial Infarction on 1-Year Outcome:Results From the French NationwideUSIC 2000 Registry

Danchin N, Blanchard D, Steg PG, et al. Circulation 2004;110:1909 –15.

Study Question: In clinical trials, it has been shown thatprehospital thrombolysis (PHT) could be used safely inpatients presenting with evidence of acute myocardialinfarction (AMI). Because data on the use of PHT in thereal-world setting and on its prognostic impact are lim-ited, the investigators analyzed data from a large pro-spective registry of patients admitted to hospital withAMI.Methods: Of 443 intensive-care units (ICUs) in France, 369(83%) prospectively collected all cases of infarction (�48 hof symptom onset) in November 2000; 1922 patients (me-dian age, 67 years; 73% men) with ST-segment-elevationinfarction were included, of whom 180 (9%) received in-travenous PHT.Results: Patients with PHT were younger than those within-hospital thrombolysis, primary percutaneous interven-tions, or no reperfusion therapy. Median time from symp-tom onset to hospital admission was 3.6 h for PHT, 3.5 h forin-hospital lysis, 3.2 h for primary percutaneous interven-tions, and 12 h for no reperfusion therapy. In-hospitaldeath was 3.3% for PHT, 8.0% for in-hospital lysis, 6.7%for primary percutaneous interventions, and 12.2% for noreperfusion therapy. One-year survival was 94%, 89%,89% and 79%, respectively. In a multivariate analysis ofpredictors of 1-year survival, PHT was associated with a0.49 relative risk (RR) of death (95% CI, 0.24–1.00;p�0.05). When the analysis was limited to patients receiv-ing reperfusion therapy, the RR of death for PHT was 0.52(95% CI, 0.25–1.08; p�0.08). In patients with PHT admit-ted in �3.5 h, in-hospital mortality was 0% and 1-yearsurvival was 99%.Conclusions: The investigators concluded that the 1-yearoutcome of patients treated with PHT compares favorablywith that of patients treated with other modes of reperfu-sion therapy; this favorable trend persists after multivariateadjustment.Perspective: Results of this nationwide prospective registryof patients admitted to ICUs for AMI in November 2000 inFrance show that PHT therapy with liberal use of earlyangioplasty offers 1-year mortality results that are at least assatisfactory as those with primary coronary angioplasty. Inpatients treated very early (those admitted within 3.5 h ofonset of chest pain), PHT offers superior efficacy comparedwith any other mode of reperfusion therapy. DM

Do Men Benefit More Than Women From anInterventional Strategy in Patients With UnstableAngina or Non-ST-Elevation Myocardial Infarction?The Impact of Gender in the RITA 3 TrialClayton TC, Pocock SJ, Henderson RA, et al. Eur Heart J 2004;25:1641–50.

Study Question: The aim of this analysis was to test thehypothesis that the differences in the benefit of early inter-vention between women and men are due to differences inthe baseline clinical characteristics and disease severity. Inaddition, differences in the management of men and womenrandomized to early intervention were explored.Methods: The RITA-3 trial randomized patients with non-ST-elevation myocardial infarction (MI) or unstable anginato strategies of early intervention (angiography followed byrevascularization) or conservative care (ischemia or symp-tom-driven angiography). In total, 1810 patients (682women and 1128 men) were randomized.Results: The risk-factor profile of women at presentation wasmarkedly different compared to men. There was evidence thatmen benefited more from an early intervention strategy fordeath or nonfatal MI at 1 year (adjusted odds ratios 0.63, 95%confidence interval [CI] 0.41–0.98 for men and 1.79, 95% CI0.95–3.35 for women; interaction p value�0.007). Men whounderwent the assigned angiogram were more likely to bereferred for coronary artery bypass surgery, even after allowingfor differences in disease severity.Conclusions: Investigators concluded that an early interven-tion strategy resulted in a beneficial effect in men that wasnot seen in women.Perspective: An early intervention strategy in patients withunstable angina or non-ST-elevation MI resulted in a beneficialeffect in men that was not evident in women. Establishing whywomen may do less well from an early intervention strategy isnot straightforward, and though several potential reasons existfor this, caution is needed in the interpretation of findings fromsuch subgroup analysis. Further research is required to evalu-ate why women do not appear to benefit from intervention andalso to identify treatments to improve the prognosis of women.One potential explanation is that, on average, women harbor agreater percentage of more diffuse and/or microvascular coro-nary disease that is less affected by interventional strategiesdirected at disease segments. DM/KE

Enoxaparin Versus Unfractionated Heparin inPatients Treated With Tirofiban, Aspirin and anEarly Conservative Initial Management Strategy:Results From the A Phase of the A-to-Z Trialde Lemos JA, Blazing MA, Wiviott SD, et al., for the A to ZInvestigators. Eur Heart J 2004;25:1688 –94.

Study Question: In high-risk patients with non-ST-elevationacute coronary syndromes (ACS), enoxaparin is generallypreferred to unfractionated heparin (UFH). However, less is

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