Management options Primary coronary angioplasty in acute myocardial infarction Ever

Accepted 15 September 1995 In 1980, De Wood et al first reported angiographic evidence of a high incidence of totally occluded or critically stenosed infarct-related arteries in the early hours of acute myocardial infarction.' Such findings prompted the use of intracoronary and later intravenous streptokinase therapy. It is now well established that after acute myocardial infarction, the earlier the infarct-related artery is recanalised, the greater the benefits to the patient both in terms of reduced infarct size and improved survival.2 There are presently two methods of achieving recanalisation of the infarctrelated artery. The first is the intravenous administration of a thrombolytic agent, resulting in the enzymatic degradation of the occlusive thrombus. The second is primary (or direct) percutaneous transluminal coronary angioplasty (PTCA). This contrasts with sequential PTCA, which may be performed at various times after thrombolytic therapy has been administered (box 1). After the promising results of early thrombolytic trials, there was considerable interest in sequential PTCA. It was observed that following successful thrombolytic recanalisation, a high-grade residual lesion was frequently observed and led Meyer et al to use PTCA after intracoronary streptokinase during the same sitting.3 This combination treatment was advocated as a means of avoiding reocclusion and recurrent ischaemia. The rationale for dealing with the flowlimiting potential of the residual plaque has led to many studies which have examined the need to proceed to PTCA at various times but there continue to be unresolved issues about optimal strategies for sequential PTCA and doubts about its efficacy. Results of the major randomised trials involving sequential PTCA have been reviewed elsewhere.4 However, primary PTCA may offer patients a better alternative to thrombolytic therapy, providing a superior mode of recanalisation. The technique of coronary artery recanalisation by primary PTCA was introduced in 1983 by Hartzler et aP and its potential advantages over thrombolytic therapy were recognised even in the early experience.5'6 Primary PTCA causes mechanical disruption of the occlusive thrombus and the underlying stenosis and results in a rapid restoration of coronary blood flow. Three years ago, three prospective randomised studies from The Netherlands7 and the US8'9 compared primary PTCA with intravenous streptokinase or tissue plasminogen activator (tPA). PTCA resulted in higher patency rates (9398%), improved left ventricular ejection fractions,7 fewer bleeding complications and less recurrent myocardial ischaemia and re-infarction, than thrombolysis. A few centres in the US and Europe perform this technique routinely, but for logistic reasons it is uncommon practice in the UK.